JP2019064273A - Liquid discharge head and liquid discharge device - Google Patents

Abstract

To provide a liquid discharge head which not only allows a negative pressure to be easily and effectively released by reducing a volume of a flow passage to be released when releasing the negative pressure and but also enables smooth restoration to a normal state after the negative pressure is released.SOLUTION: A liquid discharge head 3 comprising a discharge part 6A discharging liquid supplied from a liquid supply source via a flow passage member 5 via nozzle openings by driving of a driving element, comprises: a self-sealing unit 4 communicating with the discharge part and maintaining a negative pressure of the discharge part; means 161 for adjusting pressures in flow passages being positioned at middles of flow passages 151 to 153 between the self-sealing units and the discharge part and changing volumes of the flow passages so as to adjust pressures in the flow passages; and flow passage opening/closing means 165 positioned at the middles of the flow passages between the self-sealing units and the means for adjusting the pressures in the flow passages and opening/closing the flow passages. When the means for adjusting the pressures in the flow passages compresses the pressures in the flow passages, the means for adjusting the pressures in the flow passages decompresses the pressures in the flow passages after the flow passage opening/closing means opens the flow passages.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a liquid discharge head, a liquid discharge device, and a method of controlling a liquid discharge head, particularly when a flow path opening / closing means and an in-flow path pressure adjustment means are provided in a liquid flow path of a liquid discharge head from a liquid supply source. It is useful to apply.

  As a representative example of a liquid discharge head which discharges a droplet, an ink jet recording head which discharges an ink droplet can be mentioned. As this ink jet type recording head, for example, a head main body which discharges an ink droplet from a nozzle opening and a head main body are fixed, and the ink is supplied from an ink cartridge in which the ink is stored. There has been proposed one having a flow path member for supplying the head body. In this type of ink jet recording head, the back pressure in the head (reservoir or pressure chamber) is usually maintained at a negative pressure in order to control the position of the meniscus at a position that can cope with continuous discharge. However, air bubbles in the vicinity of the nozzle opening may be drawn into the nozzle opening due to the negative pressure at the time of wiping or the like. If air bubbles are drawn into the nozzle opening, the nozzle may be clogged.

  Therefore, it is necessary to release the negative pressure when necessary at the time of wiping or the like. Therefore, an eccentric cam as a pressure mechanism is disposed at the side of the flow path between the negative pressure generating means (differential pressure valve) and the head, and at the time of wiping, the inside of the head is pressurized by the pressure mechanism via the eccentric cam. Has been proposed (see Patent Document 1). There is also a system in which a bypass flow path for pressurized supply is provided, and pressurization by a pressurizing pump is performed directly in the head (see Patent Document 2).

JP, 2013-161827, A JP, 2011-161844, A

  However, Patent Document 1 changes the volume of the flow path due to the contact of the eccentric cam with the tube, so, for example, when the number of nozzles increases when branching downstream from this, the change of the necessary volume Hard to cause On the other hand, if it is attempted to obtain a large volume change by thickening the tube, the flow velocity is reduced by the amount by which the tube is thickened, and the exhaustability is deteriorated.

  According to Patent Document 2, it is difficult to finely adjust the amount of liquid supplied, and many fluids may be discarded wastefully.

  In addition, in some cases, it has been difficult to once release the negative pressure and to form an appropriate meniscus at the nozzle opening again after the wiping operation, due to the wiping or the like.

  Such a problem occurs not only in the flow path member used for the liquid discharge head such as an ink jet recording head but also in the flow path member used for devices other than the liquid discharge head.

  In view of the circumstances as described above, the present invention not only can reduce the volume of the flow path to be released in releasing the negative pressure easily and effectively but also to the normal state after releasing the negative pressure. It is an object of the present invention to provide a liquid discharge head, a liquid discharge device, and a control method of the liquid discharge head, which can smoothly perform the restoration of the liquid.

An aspect of the present invention for solving the above problems is a liquid discharge head including a discharge part that discharges a liquid supplied from a liquid supply source through a flow path member through a nozzle opening by driving of a drive element, A negative pressure generating unit for maintaining the negative pressure of the discharge unit in communication with the discharge unit, and a middle portion of the flow passage between the negative pressure generating unit and the discharge unit, and changing the volume of the flow passage A flow path pressure control means for controlling the pressure in the flow path, a flow path opening / closing means for opening / closing the flow path, located in the middle of the flow path between the negative pressure generating means and the flow path pressure control means And, when pressurizing the inside of the flow path by the pressure control means in the flow path, the flow path is closed by the flow path opening / closing means prior to pressurization, and the pressure control means in the flow path When the inside of the flow path is pressurized, after the flow path is opened by the flow path opening / closing means, A liquid discharge head characterized by reduced pressure in the flow path by the flow path in the pressure regulating means.
In this aspect, upon the return of the liquid discharge head to the normal operation after releasing the negative pressure, the meniscus of the nozzle opening can be formed easily and properly. That is, the pressure control means in the flow passage can be used effectively.
Here, it is preferable that the volume of the pressure control unit in the flow passage is larger than the volume of the flow passage opening / closing unit. According to this, since the volume change amount for pressure adjustment can be increased as the volume is increased, it is possible to effectively use the in-channel pressure adjustment means.
Further, the volume of the pressure control means in the flow path and the volume of the flow path opening / closing means are adjusted by the amount of displacement of the flexible members respectively possessed by the pressure control means in the flow path and the flow path opening / closing means. Moreover, it is preferable that the displacement amount of the flexible member included in the flow passage pressure adjusting means be larger than the displacement amount of the flexible member included in the flow passage opening and closing member. According to this, since the volume change amount for pressure adjustment can be made larger as the displacement amount of the flexible member is larger, it is possible to effectively use the in-channel pressure adjustment means.
Further, the negative pressure generating means includes a flexible member displaced by the negative pressure, and the flexible member included in the negative pressure generating means is more easily bent than the flexible member included in the flow passage pressure adjusting means. It is preferable that it is comprised. According to this, as the flexible member of the negative pressure generating means is more easily bent, the pressure fluctuation at the time of closing the flow path can be absorbed by the flexible member of the negative pressure generating means. It is because it is not necessary to consider the fluctuation and it is possible to effectively use the in-channel pressure adjusting means.
Further, the flow path opening / closing means is in communication with a third concave portion communicating with the discharge portion to store the liquid, and a fluid supply source supplying a fluid for operating the flow path opening / closing means to store the fluid. A fourth recess facing the third recess, and a second flexible member interposed between the third recess and the fourth recess to seal the third recess and the fourth recess , And the volume of the fourth recess is preferably smaller than that of the third recess. According to this, since the volume of the fourth recess is small, it is possible to reduce the fluctuation of the flow channel volume accompanying opening and closing. In particular, in the case where suction is performed in a state where the flow path is closed by the flow path opening / closing means provided on the supply side, the third flexible member is prevented from closing the flow path with negative pressure of suction. The pressure in the recess may be reduced, and the second flexible member may be brought into contact with the third recess. That is, there is a case where suction is performed in a state of being in contact, but even in such a case, if the volume of the fourth recess is small, the flow channel volume between the pressure reduction in the third recess and the release thereof. Fluctuation can be reduced.
Moreover, it is preferable that the said 4th recessed part has a convex part in the position contact | abutted with the said 2nd flexible member. According to this, since the second flexible member can be brought into contact with the convex portion to regulate the position of the second flexible member, the second flexible member of the fourth concave portion at the time of normal pressure and at the time of pressure reduction It is because position can be made the same.
Further, there are a plurality of sets of the flow path pressure adjustment means, the flow path opening / closing means, and the discharge unit, and a plurality of sets of fluids for driving the flow path pressure adjustment means are provided from a common fluid supply source. It is preferable that the pressure in each of the flow channels be adjusted by the all-in-flow channel pressure adjustment units by supplying the set of pressure control units in the flow channels. According to this, the configuration can be simplified in comparison with the configuration in which the fluid supply source is provided for each negative pressure release mechanism.
Further, another aspect of the present invention is a liquid discharge apparatus including the above-described liquid discharge head.
In such an aspect, not only can the volume of the flow path to be released upon release of the negative pressure accompanied by the wiping operation be reduced to easily and effectively release the negative pressure, but also the recovery to the normal state after release of the negative pressure It can be done smoothly.
Here, after wiping the nozzle surface of the discharge part of the liquid discharge head, the flow path opening / closing means opens the flow path, and the pressure control means in the flow path controls the pressure in the flow path to be reduced. It is preferable to have According to this, it is because a predetermined operation can be performed sequentially when returning to the normal operation after releasing the negative pressure.
Furthermore, another aspect of the present invention is a liquid discharge apparatus including a discharge unit that discharges a liquid supplied from a liquid supply source through a flow path member through a nozzle opening by driving of a drive element, A first flow path opening / closing means provided in the middle of a flow path between the liquid supply source and the discharge unit, which opens / closes the flow path, the liquid flow source with the liquid supply source, and the first flow path opening / closing means A second flow path opening / closing means for opening / closing the flow path, and a suction means for suctioning the liquid in the flow path from the discharge unit; In a state in which the passage is opened and the passage is closed by the second passage opening / closing unit, a first mode for suctioning by the suction unit, and a state in which the passage is closed by the first passage opening / closing unit Performing the operations of the second mode in which suction is performed by the suction unit; After the operation mode, a liquid discharging apparatus characterized by performing the operation of the second mode.
In such an embodiment, suction in each mode can be performed at a desired timing. As a result, it is possible to reduce wasteful disposal of the liquid accompanying the suction operation as much as possible by appropriately performing not only suction during initial filling but also printing operation after the initial filling.
In addition, by performing the operation in the second mode after the operation in the first mode, the exhaustability at the time of initial filling can be improved.
Moreover, it is preferable that the frequency of performing the operation of the second mode be higher than the frequency of performing the first mode. According to this, in the second mode, since the liquid consumption amount is smaller, it is possible to perform effective bubble discharge.
Further, in the operation of the first mode, it is preferable to keep the flow path open by the first flow path opening / closing means. According to this, for example, when any of air release, pressure reduction and pressure can be performed in the concave portion filled with the fluid of the flow path opening / closing means, if pressure reduction is performed when suctioning the discharge portion, the discharge portion It is possible to prevent the elastic member from unintentionally closing the flow passage when being sucked from the
Furthermore, another aspect of the present invention is a liquid discharge head including a discharge unit that discharges a liquid supplied from a liquid supply source through a flow path member through a nozzle opening by driving of a drive element, A negative pressure generating means for maintaining a negative pressure of the discharge part in communication with the discharge part, and in the middle of the flow path between the negative pressure generating means and the discharge part, changing the volume of the flow path Flow path pressure adjustment means for adjusting the pressure in the flow path, and flow path opening / closing means located in the middle of the flow path between the negative pressure generating means and the flow path pressure adjustment means; A control method of a liquid discharge head, the first step of pressurizing the inside of the flow path by the pressure control means in the flow path after closing the flow path by the flow path opening / closing means, and in the flow path When the inside of the flow path is pressurized by the pressure adjustment means, the flow path opening / closing means After opening the serial channel, the control method of the liquid discharge head is characterized in that a second step for reducing the pressure of the flow channel by the flow channel pressure regulating means.
In this aspect, the meniscus of the nozzle opening can be easily and properly formed upon returning to the normal operation of the liquid discharge head after releasing the negative pressure.
Another aspect is a liquid discharge head including a discharge unit that discharges a liquid supplied from a liquid supply source through a flow path member through a nozzle opening by driving of a drive element, and the discharge unit There is a negative pressure generating means communicating with and maintaining the negative pressure of the discharge part, and in the middle of the flow path between the negative pressure generating means and the discharge part, and changing the volume of the flow path A pressure adjusting means in the flow path for adjusting the internal pressure, and a flow path opening / closing means in the middle of the flow path between the negative pressure generating means and the pressure adjusting means in the flow path and opening / closing the flow path When the inside of the flow path is pressurized by the pressure control means in the flow path, after the flow path is opened by the flow path opening / closing means, the pressure in the flow path is reduced by the pressure adjustment means in the flow path The liquid discharge head to be
According to this aspect, upon the return of the liquid discharge head to the normal operation after the release of the negative pressure, the meniscus of the nozzle opening can be formed easily and properly. That is, the pressure control means in the flow passage can be used effectively.

  Here, it is desirable that the volume of the pressure control means in the flow passage is larger than the volume of the flow passage opening / closing means. This is because the amount of change in volume for pressure adjustment can be increased as the volume is increased, so that the pressure control means in the flow passage can be effectively used.

  Further, the volume of the pressure control means in the flow path and the volume of the flow path opening / closing means are adjusted by the amount of displacement of the flexible members respectively possessed by the pressure control means in the flow path and the flow path opening / closing means. Moreover, it is desirable that the displacement amount of the flexible member included in the flow passage pressure adjusting means be larger than the displacement amount of the flexible member included in the flow passage opening and closing member. This is because the volume change amount for pressure adjustment can be increased as the displacement amount of the flexible member is larger, so that the in-channel pressure adjustment means can be used effectively.

  Further, the negative pressure generating means includes a flexible member displaced by the negative pressure, and the flexible member included in the negative pressure generating means is more easily bent than the flexible member included in the flow passage pressure adjusting means. It is desirable to be configured. As the flexible member of the negative pressure generating means is more flexible, the pressure fluctuation at the time of closing the flow path can be absorbed by the flexible member of the negative pressure generating means, so the pressure adjusting means in the flow path does not consider the pressure fluctuation thereof. This is because the pressure control means in the flow path can be used effectively.

  Further, the flow path opening / closing means is in communication with a third concave portion communicating with the discharge portion to store the liquid, and a fluid supply source supplying a fluid for operating the flow path opening / closing means to store the fluid. A fourth recess facing the third recess, and a second flexible member interposed between the third recess and the fourth recess to seal the third recess and the fourth recess , And the volume of the fourth recess is preferably smaller than that of the third recess. According to this, since the volume of the fourth recess is small, it is possible to reduce the fluctuation of the flow channel volume accompanying opening and closing. In particular, in the case where suction is performed in a state where the flow path is closed by the flow path opening / closing means provided on the supply side, the third flexible member is prevented from closing the flow path with negative pressure of suction. The pressure in the recess may be reduced, and the second flexible member may be brought into contact with the third recess. That is, there is a case where suction is performed in a state of being in contact, but even in such a case, if the volume of the fourth recess is small, the flow channel volume between the pressure reduction in the third recess and the release thereof. Fluctuation can be reduced.

  Here, it is desirable that the fourth concave portion have a convex portion at a position in contact with the second flexible member. Since the second flexible member can be brought into contact with the convex portion to regulate the position of the second flexible member, the positions of the second flexible member in the fourth concave portion at the time of pressure reduction and at the time of pressure reduction are made the same. Because you can do it.

Another aspect of the present invention is a liquid discharge head including a discharge unit that discharges a liquid supplied from a liquid supply source via a flow path member through a nozzle opening by driving of a drive element, wherein the discharge unit In the flow passage, and in the middle of the flow passage of the liquid supply source and the pressure adjustment means in the flow passage. And the flow path opening / closing means for opening / closing the flow path, and the flow path pressure adjustment means, the flow path opening / closing means, and the discharge unit are in plural sets, By supplying the fluid for driving the means from the common fluid supply source to the plurality of sets of the in-flow-path pressure adjusting means, each set of the in-flow-path pressure adjusting means in each of the flow paths The liquid discharge head is characterized by adjusting the pressure of
According to this aspect, the configuration can be simplified in comparison with the configuration in which the fluid supply source is provided for each negative pressure release mechanism.

  Here, in the case where the pressure in each of the flow channels is adjusted by the pressure adjustment means in the flow channels of all the sets, the change in volume by the pressure adjustment means in the flow channels from the discharge parts of all the sets. It is desirable to discharge the liquid. Even if the volume required for releasing the negative pressure (hereinafter referred to as the excluded volume) differs depending on the negative pressure releasing mechanism or the corresponding head, discharge of the liquid from the negative pressure releasing mechanism or the head requiring a small required excluded volume The excluded volume can be reliably formed to the extent that negative pressure can be reliably released to all negative pressure release mechanisms and heads while permitting, and negative pressure can be reliably released. It is from.

  Here, in the case where the pressure in each of the flow paths is adjusted by the set of in-flow path pressure adjusting means, it is desirable that the discharge portion be faced to a cap member for capping the liquid discharge head. . When negative pressure is released, a cap may be disposed under the head as a countermeasure for permitting the discharge of the liquid. Thus, even if the liquid is discharged, the main body and the like are not soiled.

Another aspect of the present invention is a liquid ejection apparatus including the above-described liquid ejection head.
According to this aspect, not only the volume of the flow path to be released in releasing the negative pressure accompanying the wiping operation can be reduced to easily and effectively release the negative pressure, but also to the normal state after the negative pressure is released. Recovery can be done smoothly.

  Here, after wiping the nozzle surface of the discharge part of the liquid discharge head, the flow path opening / closing means opens the flow path, and the pressure control means in the flow path controls the pressure in the flow path to be reduced. It is desirable to have This is because the predetermined operation can be performed sequentially when returning to the normal operation after releasing the negative pressure.

Another aspect of the present invention is a liquid discharge apparatus including a discharge unit that discharges a liquid supplied from a liquid supply source through a flow path member through a nozzle opening by driving a drive element, wherein the liquid supply A first flow path opening / closing means provided in the middle of the flow path between the source and the discharge unit and opening / closing the flow path, in the middle of the flow path of the liquid supply source and the first flow path opening / closing means A second flow path opening / closing means for opening / closing the flow path, and a suction means for suctioning a liquid in the flow path from the discharge unit, and the first flow path opening / closing means In the first mode for suction by the suction means in the state where the flow path is closed by the second flow path opening / closing means, and the suction means in the state where the flow path is closed by the first flow path opening / closing means Operation in the second mode of suction by In the body ejection device.
According to this aspect, suction in each mode can be performed at a desired timing. As a result, it is possible to reduce wasteful disposal of the liquid accompanying the suction operation as much as possible by appropriately performing not only suction during initial filling but also printing operation after the initial filling.

  Here, it is desirable that the frequency of performing the operation in the second mode be higher than the frequency of performing the first mode. In the second mode, since the liquid consumption amount is smaller, it is possible to perform effective bubble discharge.

  Moreover, it is desirable to perform the operation of the second mode after the operation of the first mode. By performing the operation in both modes, the exhaustability at the time of initial filling can be improved.

  Further, in the operation of the first mode, it is desirable to keep the flow path open by the first flow path opening / closing means. For example, in a recess filled with fluid in the flow path opening / closing means, if any of air release, pressure reduction and pressure can be performed, if pressure reduction is performed when suctioning the discharge unit, suction from the discharge unit It is possible to prevent the elastic member from unintentionally closing the flow path.

Another aspect of the present invention is a liquid discharge head including a discharge unit that discharges a liquid supplied from a liquid supply source via a flow path member through a nozzle opening by driving of a drive element, wherein the discharge unit In the middle of the flow path between the negative pressure generation means and the discharge part, the volume of the flow path is changed, and the flow Flow path pressure adjusting means for adjusting the pressure in the path; and flow path opening / closing means located in the middle of the flow path between the negative pressure generating means and the flow path pressure adjusting means, for opening and closing the flow path A control method of a liquid discharge head, comprising: a first step of pressurizing the inside of the flow path by the pressure adjustment means in the flow path; and a case in which the inside of the flow path is pressurized by the pressure adjustment means in the flow path After the flow path is opened by the flow path opening / closing means, the pressure adjustment means in the flow path The control method of the liquid discharge head is characterized in that a second step of reducing the pressure in the road.
According to this aspect, upon the return of the liquid discharge head to the normal operation after the release of the negative pressure, it is possible to form the meniscus of the nozzle opening easily and properly.

FIG. 1 is a schematic perspective view showing a recording apparatus according to an embodiment of the present invention. FIG. 1 is a schematic cross-sectional view showing a liquid discharge head according to an embodiment of the present invention. It is a schematic block diagram which extracts and shows a self-sealing unit. It is an exploded perspective view showing a channel member concerning an embodiment of the invention. FIG. 1 is an exploded perspective view showing a head main body according to an embodiment of the present invention. They are a top view and a back view of a channel substrate. They are a top view and a back view of a channel substrate. They are a top view and a back view of a channel substrate. They are a top view and a back view of a channel substrate. They are a top view and a back view of a channel substrate. They are a top view and a back view showing the 1st flexible member. They are a top view and a back view showing the 2nd flexible member. It is a schematic block diagram which shows typically the other Example of a flow-path opening-and-closing means. FIG. 10 is a schematic configuration view schematically showing a liquid discharge head according to another embodiment. It is a characteristic view which shows the characteristic of the flow-path pressure adjustment means shown in FIG. FIG. 10 is a schematic configuration view schematically showing a liquid discharge device according to another embodiment.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.
A: Liquid Discharge Device The liquid discharge device according to the present embodiment is an ink jet recording device, and includes an ink jet recording head as a liquid discharge head. Then, it is a so-called line type recording apparatus which carries out printing by conveying a recording sheet such as paper as a medium to be ejected without moving the liquid discharge head.

  Specifically, as shown in FIG. 1 (which is a schematic perspective view showing the recording apparatus according to the present embodiment), the ink jet recording apparatus 100 (hereinafter also referred to as the recording apparatus 100) is disposed in the apparatus main body 2. Ink jet recording head unit 1 (hereinafter also referred to as liquid discharge head unit 1), an ink cartridge 350 which is an ink supply source storing ink supplied to the liquid discharge head unit 1, an ink cartridge 350 and a liquid discharge head An opening / closing valve 351 as a flow path opening / closing means, a conveyance means for conveying the recording sheet S as a recording medium such as paper, and a back surface opposite to the printing surface of the recording sheet S A supporting member 9, a pair of rails 11 A and 11 B fixed to the floor of the apparatus body 2, and a cleaning means 14 disposed on the floor of the apparatus body 2; And a control unit 17 for controlling the operation of each unit of the recording apparatus 100 comprises a. These will be described in detail later.

  In the present embodiment, the conveyance direction of the recording sheet S is referred to as a first direction X. Further, in the in-plane direction in which the nozzle opening of the liquid discharge head 3 opens, a direction orthogonal to the first direction X is referred to as a second direction Y. Furthermore, a direction orthogonal to the first direction X and the second direction Y is referred to as a third direction Z. In the third direction Z, the liquid discharge head 3 side of the recording sheet S is set to the Z1 side, and the opposite side is set to the Z2 side.

(A-1-1) Liquid Ejection Head Unit The liquid ejection head unit 1 according to the present embodiment is a liquid in which a plurality of inkjet recording heads 3 (hereinafter also referred to as liquid ejection heads 3) are arranged in parallel on the base plate 10. It is an assembly of the ejection head 3.

(A-1-2) Liquid Ejection Head The liquid ejection head 3 in the present embodiment corresponds to each color with the self-sealing units 4 and 4 to which two colors of ink are respectively supplied corresponding to the four colors of CMYK. The flow path member 5 in which four types of flow paths are formed is combined with the head main body 6 to form one unit, and in the present embodiment, four in the second direction Y on the base plate 10 It is installed side by side. That is, the liquid discharge head 3 is sandwiched between the two self-sealing units 4, 4 as negative pressure generating means and the self-sealing units 4, 4 from both sides, and is supplied from the self-sealing units 4, 4 A flow path member 5 for supplying ink to the head main body 6 and the head main body 6 for discharging the ink supplied via the flow path member 5 as ink droplets onto the printing surface of the recording sheet S are provided.

  In the present embodiment, the liquid discharge head 3 is disposed on the base plate 10 so as to be inclined with respect to the first direction X. Therefore, the disposition direction of the liquid discharge head 3 inclined with respect to the first direction X is orthogonal to the fourth direction Xa, and the direction inclined with the same amount with respect to the second direction Y is fifth It is referred to as the direction Ya. Both are directions on the X-Y plane.

(A-1-2-1) Head Body The head body 6, which will be described in detail later, forms a liquid flow path including a plurality of pressure generating chambers communicating with the nozzles, and causes pressure fluctuation to ink in the pressure generating chamber. A discharge unit 6A (see FIG. 5; the same applies to the following) provided with pressure generating means and the like comprising piezoelectric elements and the like, and a filter means 6B to remove foreign matter of ink supplied to the discharge unit 6A (see FIG. 5; the same applies to the following) And. The head main body 6 is disposed on the base plate 10 so as to protrude downward from the lower surface of the base plate 10.

(A-1-2-2) Self-Sealing Unit The self-sealing unit 4 seals the opening of the recess provided on the side surface intersecting the nozzle formation surface of the head main body 6 with a film, which will be described in detail later. It has a liquid flow path. Then, a valve body is disposed in the middle of the liquid flow path, and normally, the valve body is urged to close the liquid flow path, and the negative pressure of the pressure generating chamber exceeds a predetermined value as the ink is discharged. When it becomes, the valve pressed by the film displaced by the negative pressure is configured to open the liquid flow path. Thus, if a negative pressure equal to or greater than a predetermined value is generated in the discharge portion 6A of the head main body 6 with the discharge of the ink, the film presses the valve body, the valve body is opened by this pressing force, and the ink flows in the liquid flow path. It flows to supply the ink to the head body 6.

(A-1-2-3) Distribution Unit The distribution unit 18 is placed on the upper surface of the liquid discharge head 3 of each unit and extends in the second direction Y, and the liquid discharge head 3 of each unit is self-sealed The ink for each color from the ink cartridge 350 is distributed to the unit 4 and the pressure control means in the flow path member 5 (not shown in FIG. 1) and the flow path opening / closing means (shown in FIG. 1). Air for driving control is distributed to the flow path members 5 respectively. Here, the dimension (height) in the third direction of the self-sealing unit 4 and the dimension (height) in the third direction of the flow path member 5 are configured to be the same. As a result, the installation of the distribution unit 18 that functions as a distribution flow path of ink and air with respect to the liquid discharge head 3 of each unit is facilitated. More specifically, the self-sealing unit 4 and the flow path member 5 are connected to a common distribution unit 18, and this connection is a negative pressure on a projection (convex needle) provided on the lower surface of the distribution unit 18. It is performed by inserting in the hole (concave insertion port) provided in each upper surface of the self-sealing unit 4 and the flow-path member 5 which are a generation means. The distribution unit 18 is provided with a groove along a second direction Y on a planar substrate, and the groove is sealed with a film to provide a flow path having a distribution function to the liquid discharge head 3 of each unit. And Therefore, the top surfaces of the self-sealing unit 4 and the flow path member 5 are aligned in the height direction which is the third direction Z, in order to align with the grooves provided along the flat surface of the distribution unit 18. When inserting the protrusions of the distribution unit 18 into the self-sealing unit 4 and the hole on the upper surface of the flow path member 5, the protrusions of the distribution unit 18 are prevented in order to prevent the resistance from acting simultaneously on all the protrusions. The length is divided into long and short.

(A-1-2-4) Flow path member The flow path member 5 will be described in detail later, but the stacked flow path substrates 101, 102, 103, 104, 105, the first flexible member 160, and the second It is formed of a flexible member 164 and functions as an in-flow path pressure adjusting means 161 and a flow path opening / closing means 165.

  The pressure control means 161 in the flow path is located in the middle of the liquid flow path between the self-sealing unit 4 and the head main body 6 and changes the volume of the liquid flow path to adjust the pressure in the liquid flow path.

  The flow path opening / closing means 165 is in the middle of the liquid flow path between the self-sealing unit 4 and the pressure control means 161 in the flow path, and opens / closes the liquid flow path.

(A-2) Conveying Means The conveying means moves the recording sheet S relative to the liquid discharge head 3 in the first direction. The transport means includes, for example, a first transport roller 7 provided on both sides in the first direction X, which is the transport direction of the recording sheet S with respect to the liquid discharge head 3, and a second transport roller 8. The recording sheet S is conveyed on the upstream side and the downstream side in the first direction X of the liquid discharge head unit 1 by the first conveyance roller 7 and the second conveyance roller 8. The conveyance means for conveying the recording sheet S is not limited to the conveyance rollers 7 and 8, and may be a belt, a drum or the like.

(A-3) Support Member The support member 9 supports the recording sheet S at a position facing the liquid discharge head unit 1. The support member 9 has, for example, a rectangular cross section provided opposite to the nozzle surface of the liquid discharge head 3, particularly the head main body 6, between the first conveyance roller 7 and the second conveyance roller 8. The recording sheet S which is provided with a metal, a resin, or the like and is conveyed by the first conveyance roller 7 and the second conveyance roller 8 is supported at a position opposite to the liquid discharge head unit 1.

  Note that the support member 9 may be provided with a suction unit that sucks the conveyed recording sheet S on the support member 9. As the suction means, for example, one suctioned and adsorbed by suctioning the recording sheet S, and one electrostatically adsorbed the recording sheet S by electrostatic force may be mentioned.

  In the recording apparatus 100, the recording sheet S is conveyed by the first conveyance roller 7, and printing is performed on the recording sheet S supported on the support member 9 by the liquid discharge heads 3. The printed recording sheet S is conveyed by the second conveyance roller 8.

(A-4) Pair of Rails The pair of rails 11A and 11B are extended in the second direction Y, and the floor of the apparatus main body 2 via the support members 12A, 12B and 12C and the support members 13A, 13B and 13C. It is fixed to the surface. The rails 11A and 11B are rod-like members each having a C-shaped receiving section. Both ends of the base plate 10 in the first direction X are inserted into the receiving portion. Thus, the base plate 10 is supported between the rails 11A and 11B and can move along the second direction Y. As a result, the liquid discharge head unit 1 is movable in the second direction along the rails 11A and 11B in a state of being disposed on the base plate 10. That is, it moves from the proximal end side which is one end side of the rails 11A and 11B in the second direction Y to the distal end side which is the other side, and also moves to the opposite side.

(A-5) Cleaning Means A cleaning part for cleaning the nozzle surface (not shown) of the head main body 6 on the floor of the apparatus main body 2 between the rails 11A and 11B, which is a midway part of the rails 11A and 11B. Means 14 are provided. The cleaning means 14 in the present embodiment has a wiping means 15 and a suction means 16.

  The wiping means 15 has a wiping blade for wiping the nozzle surface which is a droplet discharge surface, and the tip of the wiping blade is moved to the nozzle surface by the movement of the liquid discharge head unit 1 along the second direction Y at a predetermined timing. And a wiping operation to wipe the nozzle surface is performed.

  The suction means 16 is disposed on the floor of the apparatus body 2 adjacent to the wiping means 15 in the second direction Y, and moves the liquid discharge head unit 1 along the second direction Y at a predetermined timing. While covering the nozzle surface with a cap member and applying a negative pressure to suction the inside of the cap member, a suction operation for forcibly discharging ink or the like from the nozzle opening is performed. Here, with the movement of the base plate 10 along the Y direction, the head main body 6 in which the wiping and suction are performed is sequentially positioned above the wiping means 15 and the suction means 16 in the third direction Z to perform predetermined work. To be executed.

(A-6) Control device The control device 17 controls the operation of each part of the recording device 100, and controls the discharge of ink droplets in the liquid discharge head 3 and the conveyance control of the recording sheet S, and the base plate 10 to a predetermined position. Control of the cleaning operation at a predetermined timing that involves the movement of In addition, control of opening and closing of the on-off valve 351 and control of driving of the in-flow passage pressure adjusting means 161 and the passage opening and closing means 165 via air are also performed.

B: Liquid Ejection Head FIG. 2 is a schematic cross-sectional view schematically showing a liquid ejection head according to the embodiment of the present invention. As shown in the figure, the liquid discharge head 3 according to the present embodiment has two self-sealing units 4 and 4 which are negative pressure generating means, a flow path member 5 and a head main body 6. The self-sealing units 4 and 4 are disposed on both sides of the flow path member 5 in the fifth direction Ya. The self-sealing unit 4, 4 will be described in detail later, but four color inks of CMYK are respectively supplied through two ink supply ports 126, (127) respectively. In FIG. 2, the ink supply port 127 is not shown because it overlaps the ink supply port 126. Ink of any color of CMYK is supplied to the ink supply ports 126 and (127) from ink storage means such as an ink cartridge.

(B-1-1) Structure of pressure adjustment means in flow passage The flow passage member 5 is formed by laminating five flow passage substrates 101, 102, 103, 104, and 105. Here, the first concave portion 158 is formed on the Z2 side surface of the flow path substrate 104 in the third direction Z (hereinafter referred to as the lower surface), and the Z1 side surface of the flow path substrate 105 (hereinafter referred to as the upper surface) The second recess 159 is formed opposite to the first recess 158. A first flexible member 160 made of, for example, rubber is interposed between the first recess 158 and the second recess 159. As a result, the first recess 158 and the second recess 159 are two chambers sealed by the first flexible member 160. Thus, the displacement of the first flexible member 160 in the third direction Z can adjust the volume of the first recess 158. An air flow path 172 opened on the upper surface of the flow path substrate 101 penetrates the flow path substrates 101, 102, 103, and 104 and reaches the upper surface of the flow path substrate 105. A horizontal flow passage 172A communicating with the second recess 159 is formed on the upper surface of the flow passage substrate 105, whereby the air supply port 170 provided on the upper surface of the flow passage substrate 101 leads to the second recess 159 The air flow path 172 is communicated. Therefore, by adjusting the amount of air supplied from the air supply source (not shown) which is the first fluid supply source for supplying the fluid for driving the pressure control means 161 in the flow path via the air supply port 170, The displacement amount of the flexible member 160 can be adjusted. As described later, the first recess 158 communicates with the ink flow path. That is, the volume of the ink flow path is changed by the first concave portion 158, the second concave portion 159, and the first flexible member 160, thereby forming the in-flow path pressure adjusting means 161 for adjusting the pressure in the ink flow path. Here, although not shown, a spring that applies an urging force from the first concave portion 158 to the second concave portion 159 is disposed in the first concave portion 158.

  The remaining three first recesses 158 and second recesses 159 having the same configuration are formed on the lower surface of the flow path substrate 104 and the upper surface of the flow path substrate 105, and the first flexible member 160 is formed on the first recesses 158 thereof. And the second recess 159. That is, a total of four in-flow-path pressure adjustment means 161 corresponding to the respective colors of CMYK are dispersedly disposed on the Xa-Ya plane formed by the lower surface of the flow path substrate 104 and the upper surface of the flow path substrate 105 . Air is supplied to each of the second concave portions 159, including the remaining three, via the horizontal flow path 172A branched in the horizontal direction at the lower end of the air flow path 172, and the same function is exhibited. The first concave portion 158 communicates with the ink flow path, and the second concave portion 159 communicates with the air flow path, and the first flexible member 160 seals them. The first concave portion 158 is also referred to as a first concave portion (ink chamber) 158, and the second concave portion 159 as an air chamber is also referred to as a second concave portion (air chamber) 159.

(B-1-2) Structure of flow path opening / closing means On the other hand, the third recess 162 is formed on the upper surface of the flow path substrate 103, and the lower surface of the flow path substrate 102 faces the third recess 162. Four recessed portions 163 are formed. A second flexible member 164 formed of, for example, rubber is interposed between the third recess 162 and the fourth recess 163. As a result, the third concave portion 162 and the fourth concave portion 163 are two chambers sealed by the second flexible member 164. Thus, the displacement of the second flexible member 164 in the third direction Z can close or open the flow path. An air flow path 171 opened on the upper surface of the flow path substrate 101 penetrates the flow path substrate 101 and reaches the upper surface of the flow path substrate 102. A horizontal flow path 171A is formed on the upper surface of the flow path substrate 102, and the air flow path 171 communicates with the fourth recess 163 via the horizontal flow path 171A. As a result, the air flow path 171 from the air supply port 169 provided on the upper surface of the flow path substrate 101 to the fourth concave portion 163 is communicated. Therefore, the second flexible member 164 is displaced by supplying air from the air supply source (not shown) which is the second fluid supply source for supplying the fluid for driving the flow path opening / closing means 165 via the air supply port 169. Open and close the flow path. As described later, the first recess 158 communicates with the ink flow path. That is, the third concave portion 162, the fourth concave portion 163, and the second flexible member 164 form the flow path opening / closing means 165 for opening / closing the ink flow path.

  The third concave portion 162 and the fourth concave portion 163 having the same configuration are formed on the upper surface of the flow path substrate 103 and the lower surface of the flow path substrate 102, and the second flexible member 164 is further formed in the third concave portion 162 thereof. And the fourth concave portion 163. That is, a total of four flow path opening / closing means 165 corresponding to each color of CMYK are distributed and disposed at the central portion of the Xa-Ya plane formed by the upper surface of the flow path substrate 103 and the lower surface of the flow path substrate 102 There is. Air is supplied to each fourth concave portion 163 including the remaining three through the horizontal flow path 171A formed between the lower surface of the flow path substrate 101 and the upper surface of the flow path substrate 102 and branched in the horizontal direction. And the same function is exhibited. The third concave portion 162 communicates with the ink flow path, and the fourth concave portion 163 communicates with the air flow path, and the second flexible member 164 seals them. The third concave portion 162 is also referred to as a third concave portion (ink chamber) 162, and the fourth concave portion 163 as an air chamber is also referred to as a fourth concave portion (air chamber) 163.

  In this embodiment, the volume change amount for pressure adjustment can be increased as the displacement amount of the first or second flexible member 160, 164 is larger, so the volume of the first recess 158 is larger than the volume of the third recess 162. It is configured. As a result, predetermined pressure adjustment by the flow passage pressure adjustment means 161 can be easily and accurately performed.

(B-1-3) The flow path of the flow path member The ink supplied to the flow path member 5 from the one self-sealing unit 4 which is a negative pressure generating means discharges the head main body 6 via the flow path member 5 It is supplied to section 6A.

  For this reason, in the flow path member 5, flow paths 151, 152, 153 are formed as ink flow paths. The channel 151 is for introducing the ink supplied from one of two self-sealing valves (not shown in FIG. 2) of one self-sealing unit 4 into the third recess 162. That is, the flow path 151 descends the flow path substrate 103 from the lower surface of one self-sealing unit 4 along the third direction Z from Z1 to Z2, and the lower surface of the flow path substrate 103 and the flow path substrate 104 Horizontally along the fifth direction Ya and extended from Ya1 to Ya2 along the fifth direction Ya, the flow path substrate 103 is further raised along the third direction Z from Z2 to Z1 and opened in the third recess 162 ing. The flow path 152 communicates the third recess 162 and the first recess 158 via the flow path substrate 103 and the flow path substrate 104. The flow path 153 raises the flow path substrate 104 from the first recess 158 along the third direction Z from Z2 toward Z1 in the fifth direction Ya on the Ya1 side relative to the flow path 152 in the fifth direction Ya. Between the lower surface of the channel substrate 104 and the upper surface of the flow path substrate 104 horizontally from the Ya2 to Ya1 along the fifth direction Ya, further penetrating the flow path substrates 104 and 105, and along the third direction Z1 To Z2 to be communicated with the flow path of the head main body 6. In the flow path 153, a portion extending horizontally from the lower surface of the flow path substrate 103 to the upper surface of the flow path substrate 104 and along the fifth direction Ya from Ya2 to Ya1 is a flow A portion of the path 151 extending horizontally from the lower surface of the flow path substrate 103 to the upper surface of the flow path substrate 104 along the fifth direction Ya and from Ya1 to Ya2 in the first direction X It is not shown because it overlaps.

(B-1-4) Function of pressure control means in flow path and flow path opening / closing means Thus, the flow path from self sealing unit 4 which is negative pressure generating means to discharge portion 6A through filter means 6B of head main body 6 151, 152, 153 are formed, and the flow path opening / closing means 165 is disposed between the flow path 151 and the flow path 152, and the pressure adjustment in the flow path between the flow path 152 and the flow path 153 The means 161 is provided. That is, a flow path extending from the self-sealing unit 4 downstream through the flow path opening / closing means 165 and the in-flow path pressure adjusting means 161 to the head main body 6 is formed. The pressure is adjusted by the internal pressure adjusting means 161 and the space between the in-flow path pressure adjusting means 161 and the self-sealing unit 4 is opened and closed by the flow path opening / closing means 165. The channels 151, 152, and 153 are formed in the Xa-Ya plane of the channel substrates 103, 104, and 105 so as to correspond to the respective colors as channels having the same configuration.

  According to the liquid discharge head 3, the following operations and effects are obtained. In this type of liquid discharge head 3, the back pressure in the head (reservoir or pressure chamber) is maintained at a negative pressure in order to control the position of the meniscus so as to be able to cope with continuous discharge. In addition, air bubbles near the nozzle opening may be drawn into the nozzle opening by the negative pressure. If air bubbles are drawn into the nozzle opening, the nozzle may be clogged.

  Therefore, in order to release the negative pressure, the volume in the flow channel is reduced by the pressure control means in the flow channel 161 to pressurize the flow channel. At this time, if the overall volume in the flow channel is larger than the volume fluctuation due to the flow channel pressure adjusting means 161, pressurization in the flow channel can not be effectively performed against the volume fluctuation. Furthermore, if there is a compliance portion in the flow path, the compliance portion absorbs the volume change, and pressurization due to the volume change in the flow path pressure adjustment means 161 can not be performed effectively. In particular, in the case of using the self-sealing unit 4 as the negative pressure generating means, as described in detail later, since the films 112 and 113 as the flexible members are used, the flexible members become the compliance portions.

  Therefore, in order to effectively perform pressurization, a flow path opening / closing means 165 is provided on the downstream side of the self-sealing unit 4 and on the upstream side of the flow path pressure adjusting means 161. The flow path is closed by the flow path opening / closing means 165 prior to pressurization by the

  When the pressurization is released to a negative pressure, the flow path opening / closing means 165 is opened and then the volume is increased by the in-flow path pressure adjustment means 161. When the volume is increased by the in-flow path pressure adjusting means 161 first, there is a possibility that air bubbles are also drawn when the meniscus position is displaced in the drawing direction. On the other hand, if the flow path opening / closing means 165 is opened in advance, ink can be supplied from the flow path opening / closing means 165 or the upstream side even if the volume is increased by the flow path pressure adjusting means 161. With the drawing in of the meniscus position, the possibility that the air bubble is also drawn can be reduced.

(B-2) Structure of self-sealing unit FIG. 3 is a schematic diagram showing the self-sealing unit, and FIG. 3 (a) is a schematic diagram as seen from the fifth direction Ya, FIG. 3C is a schematic configuration view seen from the Z1 side with respect to the third direction Z, and FIG. 3C is a schematic configuration view seen from the AA 'cross section of FIG. 3A. As shown in these figures, the self-sealing unit 4 is a substantially rectangular member as a whole, and the films 112 and 113 are attached by heat welding or the like on both sides of the side surface along the longitudinal direction of the main body 111. is there. That is, the self-sealing unit 4 has a film surface along the fourth direction Xa and has two film surfaces facing each other in the fifth direction Ya.

  On the other hand, in the main body 111, a concave portion (see FIG. 3C) is formed on one side (left side in the figure) with respect to the fourth direction Xa of one of two surfaces facing each other in the fifth direction Ya. The same recess (see FIG. 3C) is also formed on the other side (right side in the drawing) of the other surface in the fourth direction Xa. Such a recess is a space sealed by the films 112 and 113. As a result, the films 112 and 113 are displaced in the fifth direction Ya due to a change in pressure in the space. That is, the diaphragm chambers 114 and 115 are formed by the films 112 and 113 and the concave portions. On the side opposite to the diaphragm chamber 114, 115, a valve chamber 118, 119 which is a recess smaller than the recess via the communication holes 116, 117 and which is sealed by the films 113, 112 is formed. .

  The other end of the shaft 122 passing through the communication hole 116 is fixed to the valve body 120. One end of the shaft 122 is fixed to the film 112 via a pressure receiving plate or the like (not shown). That is, the valve body 120 is on the opposite side of the communication hole 116 to the film 112. In this embodiment, the valve body 120 side with respect to the communication hole 116 is the Ya1 side with respect to the fifth direction Ya, and the film 112 side with respect to the communication hole 116 is the Ya2 side with respect to the fifth direction Ya. Further, the valve body 120 is pressed by the spring 124 from the Ya1 side toward the Ya2 side. The displacement of the film 112 and the biasing of the spring 124 cause the valve body 120 to open and close the communication hole 116. The spring 124 is fixed to the main body 111 via a spring receiver or the like (not shown).

  Similarly, the other end of the shaft 123 passing through the communication hole 117 is fixed to the valve body 121. One end of the shaft 123 is fixed to the film 113 via a pressure receiving plate or the like (not shown). That is, the valve body 121 is on the opposite side of the communication hole 117 to the film 113. The valve body 121 is pressed by the spring 125 from the Ya2 side toward the Ya1 side. The valve body 121 opens and closes the communication hole 117 by the displacement of the film 113 and the biasing of the spring 125. The spring 125 is fixed to the main body 111 via a spring receiver or the like (not shown). Thus, the valve body 120 and the valve body 121 which adjoin in the 4th direction Xa are located in the both sides of the 5th direction Ya with respect to the communicating holes 116 and 117 of each other.

  Thus, when negative pressure acts on the diaphragm chambers 114 and 115, the portions of the films 112 and 113 corresponding to the diaphragm chambers 114 and 115 are displaced along the fifth direction Ya due to atmospheric pressure or the like. As a result, the valve body 120 moves to the Ya1 side in FIG. 3C and the valve body 121 moves to the Ya2 side in FIG. 3C to open the communication holes 116 and 117. Here, a negative pressure in the interior of the head main body 6 is applied to the diaphragm chambers 114 and 115 as the head main body 6 discharges ink through the nozzles.

  Thus, the self-sealing unit 4 in the present embodiment forms the self-sealing valve I formed by the film 112, the recess forming the diaphragm chamber 114, the valve body 120, the shaft 122 and the spring 124, the film 113 and the diaphragm chamber 115 And a self-sealing valve II formed of a valve body 121, a shaft 123 and a spring 125. Here, the self-sealing valves I and II are disposed to be separated in the fourth direction Xa. As a result, the dimensions of the self-sealing unit 4 in the third direction Z are reduced so that the shafts 122 and 123 of the valve elements 120 and 121 do not overlap in the third direction Z.

  An ink supply port 126 for supplying ink to the self-sealing valve I side and an ink supply port 127 for supplying ink to the self-sealing valve II side are provided on the upper surface on the Z1 side in the third direction Z of the main body 111 Are in communication with the internal flow path. Thus, the inflowing ink F111 flowing to the self-sealing valve I side through the ink supply port 126 is supplied as the outflowing ink F112 to the head main body 6 from the lower surface formed on the Z2 side of the main body 111 and through the ink supply port 127 The inflowing ink F121 which flows into the self-sealing valve II side is supplied to the head main body 6 from the lower surface of the main body 111 as the outflowing ink F122. More specifically, the ink supplied from the ink supply port 126 reaches the valve chamber 118. In this state, a negative pressure inside the head main body 6 acts to exert a predetermined negative pressure or more on the diaphragm chamber 114, and when the valve body 120 opens the communication hole 116 due to the displacement of the film 112, the communication hole accordingly. Ink flows into the diaphragm chamber 114 via 116 and is introduced into the flow path 130 where the outlet portion 128 faces the diaphragm chamber 114 and descends on the back side of the main body 111 to discharge the lower surface of the main body 111 as outflow ink F112. It is supplied to the head main body 6 via an outlet (not shown).

  On the other hand, the ink supplied from the ink supply port 127 reaches the valve chamber 119. In this state, when a negative pressure acts on the diaphragm chamber 115 and the valve body 121 opens the communication hole 117 by the displacement of the film 113, the ink flows into the diaphragm chamber 115 through the communication hole 117 accordingly, and this diaphragm It is introduced into the flow path 131 in which the outlet portion 129 faces the chamber 115, descends the surface side of the main body 111, and is supplied to the head main body 6 through the discharge port (not shown) of the lower surface of the main body 111 .

  Furthermore, in the present embodiment, chamfered portions 132 and 133 are formed on both end surfaces of the main body 111 in the fourth direction Xa in FIG. 3, and the occupied space when arranging a plurality of self-sealing units 4. To reduce as much as possible. That is, since the film surfaces of the films 112 and 113 are arranged along the fourth direction Xa, the external shape of the self-sealing unit 4 viewed from the Z1 side in the third direction Z is the self-sealing unit 4 If it is rectangular, the dimension in the first direction X is increased. On the other hand, as shown in FIG. 3B, by providing the chamfered portions 132 and 133 in the self-sealing unit 4, the dimension in the first direction X is miniaturized.

  Further, both of the flow paths 130 and 131 in the self sealing valves I and II are disposed between the shafts 122 and 123 of the adjacent self sealing valves I and II. As a result, the dimensions of the self-sealing unit 4 in the fourth direction Xa as compared with the case where the channels 130, 131 are disposed on both end sides of the main body 111 in the fourth direction Xa than the shafts 122, 123 Can be made smaller. In addition, when forming the chamfered portions 132 and 133 on the end face of the main body 111 in the fourth direction Xa by arranging both of the flow paths 130 and 131 between the shafts 122 and 123, the flow paths The position of 130, 131 does not become an obstacle, and it is devised so that the occupied space at the time of arranging a plurality of self sealing units 4 concerned can be reduced as much as possible.

  Further, as clearly shown in FIG. 3A, the self-sealing valves I and II in this embodiment are formed so that a part of the diaphragm chambers 114 and 115 overlap when viewed in the fifth direction Ya. Yes. Since the self-sealing valves I and II can be brought close to the central portion of the main body 111 in the fourth direction Xa by partially overlapping in this manner, this also reduces the dimension in the fourth direction Xa. In addition, the chamfers 132 and 133 can be easily formed.

  In the self-sealing unit according to the present embodiment, the ink which is pressure-fed and supplied from the distribution unit 18 is discharged toward the flow path member 5 through the diaphragm chambers 114 and 115 which exhibit the self-sealing valve function. Ru. As a result, even if the ink supplied from the ink supply source is pressurized, the inside of the head body 6 can be maintained at a negative pressure.

(B-3) Layered Structure of Channel Member FIG. 4 is an exploded perspective view showing the channel member according to the embodiment of the present invention. In the figure, the same parts as those in FIG. 2 are assigned the same reference numerals and redundant explanations are omitted.

  The flow path member 5 is formed by laminating the flow path substrates 101 (see FIG. 2), 102 (see FIG. 2), 103, 104, and 105. However, since the flow path substrates 101 and 102 are housed inside the housing 173, they are not shown. In addition, air supply ports 169 and 170 are provided on the upper surface of the housing 173, and the air supply ports 169 and 170 are connected to the distribution unit 18 (not shown) via the bushing 178 and washer 179 respectively. It is communicated. Although not shown, the two self-sealing units 4 are disposed in contact with the side wall surfaces 173A and 173B of the housing 173. The housing 173 and the stacked flow path substrates 103 to 105 are firmly fastened and integrated by a plurality of fastening screws 174 and nuts 176 screwed respectively. This is due to the following reason. The uppermost member in the height direction of the flow passage pressure adjusting unit 161 forms an air flow passage 172 communicating with the flow passage opening / closing unit 165. Pressurized air is sent to the air flow path 172. Therefore, in order to maintain the strength as pressurized air flows in the air flow path 172 and also as the air flow path 172, it is firmly fixed by the fastening screw 174 and the nut 176.

  On the other hand, the fastening screw 175 for fixing the uppermost member in the height direction of the flow passage pressure adjusting means 161 integrates only the flow passage substrates 103 to 105 together with the nut 177 screwed thereto. This is because the second flexible member 164 provided in the flow path opening / closing means 165 is at a position overlapping the rubber.

  As described above, in the present embodiment, the flow path substrates 101 to 105 have a stacked structure, but the reason is as follows. In this embodiment, in order to easily change the volume in the flow path, the pressure control means 161 in the flow path has a shape in the middle of the flow path in which the pressure receiving area of the rubber as the first flexible member 160 is increased. The shape of the rubber is displaced. Moreover, as described later, since the rubber between CMYK colors is not a separate member but a single rubber, the in-flow path pressure adjusting means 161 of each color is disposed on the same plane. Therefore, the surplus space is reduced in the Xa-Ya in-plane direction in which the rubber is disposed. Therefore, the pressure control means 161 in the flow path and the flow path opening / closing means 165 are divided into different layers and stacked.

  In addition, for each color of CMYK, the lamination position of the in-flow path pressure adjustment means 161 and the in-flow path opening / closing means 165 is the same among the respective colors, and the first flexible member 160 of the in-flow path pressure adjustment means 161 or The rubber which is the second flexible member 164 of the flow path opening / closing means 165 can be disposed on the same plane among the colors. For this reason, the position which a reaction force produces can be on the same plane, and fixation of the flow-path board | substrates 101-105 of laminated structure can be made stronger. Here, the second flexible member 164 for each color of CMYK may be a single rubber member. Such a structure is preferable from the viewpoint of sandwiching of rubber.

  In addition, since the stacking position of the in-flow path pressure adjusting means 161 and the flow path opening / closing means 165 is the same, the ink flow path between the in-flow path pressure adjusting means 161 and the flow path opening / closing means 165 and the air flow path are also stacked by CMYK. The position can be made the same. Therefore, the flow path substrates 103 to 105, which are laminated substrates for forming each flow path, can also be a single member among CMYK.

  Further, in the present embodiment, the flow path opening / closing means 165 is stacked on the upstream side of the ink, and the flow path pressure adjustment means 161 is stacked on the downstream side. For this reason, the flow path substrates 103 to 105 which are laminated substrates constituting the flow path opening / closing means 165 and the flow path internal pressure adjustment means 161 are the fourth concave portion (air chamber) 163 → of the flow path opening / closing means 165 from the upstream side. The third recess (ink chamber) 162 of the flow path opening / closing means 165 → the first recess (ink chamber) 158 of the flow path pressure adjusting means 161 → the second recess (air space) 159 of the flow path pressure adjusting means 161 It is piled up in order. By arranging the flow path substrates 103 and 104 for stacking ink sequentially from the top to the third and fourth layers, the number of through holes and grooves for the ink flow path can be reduced in the lamination substrate be able to. The air for the flow path opening / closing means 165 and the air for the flow path pressure adjusting means 161 have to be pressurized at different timings as described later, so the air flow path 171, It can not but be 172. Even if the laminated substrate for this air is continuous from the top to the second and third layers, the number of laminated substrates increases if the laminated substrate for the air flow path is sandwiched therebetween.

  The volume of the latter is larger than the volume of the former in the third recess 162 which is the ink chamber of the flow path opening / closing means 165 and the first recess 158 which is the ink chamber in the flow path pressure adjusting means 161. The flow path opening / closing means 165 only needs to be able to open / close the flow path, whereas the in-flow path pressure adjusting means 161 has a larger fluctuation range to adjust the pressure in the flow path by changing the flow path volume. Because we want to have Therefore, the installation area of the pressure control means 161 in the flow path is larger than the installation area of the flow path opening / closing means 165. And in order to miniaturize the whole case, the flow path opening / closing means 165 is a self-sealing which is a negative pressure generation means with respect to the layer provided with the flow path from the negative pressure generation means (self-sealing unit 4). On the unit 4 side, the in-channel pressure adjusting means 161 is disposed on the opposite side. As a result, the flow path opening / closing means 165 is disposed between the self-sealing unit 4 in the Xa-Ya in-plane direction of the layer. In each of the in-flow path pressure adjusting means 161 and the flow path opening / closing means 165 in which the first and third recesses 158 and 162 which are ink chambers are sealed by rubber as the first and second flexible members, The term “volume” refers to the volume in the state where the first and second flexible members 160 and 162 are not displaced.

  In addition, the flow path 153 from the flow path pressure adjustment means 161 needs to be brought to the four corners of the head unit in consideration of access to the relay substrate disposed on the X-Y plane on the downstream side thereof When viewed in the stacking direction, the third concave portion 162 which is the ink chamber of the flow path opening / closing means 165 and the first concave portion 158 which is the ink chamber of the pressure control means 161 in the flow path partially overlap It has been arranged.

  In addition, although the air supply source of the pressure control means 161 in the flow path is common, the pressure in the flow path is drawn because the air flow path having the through holes provided in the flow path substrates 101 to 104 from the air supply port 170 in the stacking direction. The air flow path of the adjustment means 161 branches at the lowermost side in the stacking direction. As a result, for example, the number of through holes provided in the laminated substrate can be reduced as compared with the case of branching at the uppermost side in the laminating direction, which contributes to the miniaturization in the XY direction in particular.

  The seal member 204 is sandwiched between the flow path substrate 103 and the flow path substrate 102 (not shown in FIG. 4) to form a third recess 162 which is an ink chamber and a fourth recess 163 which is an air chamber. Is a member for sealing with (not shown). The seal member 206 is sandwiched between the flow path substrate 105 and the flow path substrate 104 and seals the second recess 159 which is an air chamber and the first recess 158 (not shown in FIG. 4) which is an ink chamber. The first flexible member 160 is formed of a flexible rubber member. The first flexible member 160 in this embodiment is formed integrally with four colors of CYMK.

  The first flexible member 160 is always urged toward the second recess 159 by a spring 203 as urging means. As a result, usually, the volume of the first recess 158 (not shown in FIG. 4), that is, the volume of the in-channel pressure adjusting means 161 is maximized.

  The ink supplied from the self-sealing unit 4 (see FIG. 2) flows from the four ink inflow ports 201 provided in the flow path substrate 103 to lead to the flow path 151. That is, after descending from Z1 to Z2 along the third direction Z, after passing through the horizontal flow path formed in the flow path substrate 104 and then rising from Z2 to Z1 along the third direction Z , And the third recess 162 of the flow path substrate 103 through the hole 162A. Furthermore, it passes through the flow path 152 through the hole 162B of the third concave portion 162, and reaches the first concave portion 158 (not shown in FIG. 4) formed on the back surface of the flow path substrate 104. Thereafter, through the flow path 153 provided in the flow path substrate 104, the head main body 6 (not shown in FIG. 4) communicated via the bushing 207 is supplied.

(B-4) Head Body FIG. 5 is an exploded perspective view showing the head body 6 according to the embodiment of the present invention. As shown in the figure, the head main body 6 is composed of the discharge part 6A and the filter means 6B, and is integrated by fixing the filter means 6B to the discharge part 6A with a screw 211. Furthermore, the filter means 6B comprises a filter portion 6B1 and a case portion 6B2. The flow path member 5 is connected to the four ink inflow portions 208 corresponding to the respective colors CMYK of the case portion 6B2 via the bushings 207 shown in FIG. 2) and further connected to an ink cartridge 350 (see FIG. 1), which is an ink supply source, via an on-off valve 351. The filter 209 is formed by knitting metal thin wires in a mesh shape, and by passing the ink, it captures and removes foreign substances in the ink. The filter 209 is disposed at an opening 210 formed in the case 300 of the filter portion 6B1. As a result, the ink supplied from the flow path member 5 has its foreign matter removed by the filter 209 for each color of CMYK and is supplied to the discharge unit 6A.

  The ejection unit 6A ejects an ink droplet through a nozzle opening (not shown) by driving a drive element such as a piezoelectric actuator, for example. Therefore, for example, the pressure generating unit is not particularly limited as long as the pressure generating unit can generate a pressure change in the pressure generating chamber filled with the ink, but a piezoelectric actuator stacked in the third direction Z is used. It can apply suitably. This type of piezoelectric actuator also includes, for example, a thin film type formed by film formation and lithography, a thick film type formed by a method of attaching a green sheet, and the like. Moreover, the piezoelectric actuator can use a longitudinal vibration type in which a piezoelectric material and an electrode forming material are alternately stacked and expanded and contracted in the axial direction. Furthermore, as a pressure generating means, a heat generating element is disposed in the pressure generating chamber, and a bubble generated by heat generation of the heat generating element is used to discharge droplets from the nozzle opening, or static electricity is generated between the diaphragm and the electrode. It is also possible to use a so-called electrostatic actuator or the like which deforms the diaphragm by electrostatic force and discharges an ink droplet from the nozzle opening.

(B-5) Characteristics and Shapes of Laminated Substrates and Elastic Members Among the plan views of the flow channel substrates 101 to 105, the surface views as viewed from the Z1 side are shown in FIG. 6A to FIG. The back view seen from the side is shown as FIG.6 (b)-FIG.10 (b), respectively. 11 (a) is a top view showing the first flexible member, FIG. 11 (b) is a back view thereof, FIG. 12 (a) is a plan view showing the second flexible member, and FIG. FIG. The drawings are added to continue the description of the liquid discharge head 3 according to the present embodiment. In these drawings, the same parts as in FIG. 2 and FIG. 4 are assigned the same reference numerals and duplicate explanations are omitted.

  While the elastic member of the self-sealing unit 4 which is the negative pressure generating means in the present embodiment is formed of the films 112 and 113, the elastic member of the in-flow path pressure adjusting means 161 and the in-flow path opening / closing means 165 The first and second flexible members 160 and 164 are formed of rubber. The reason is as follows. When comparing rubber as a flexible member with a film, rubber needs to be firmly held using a screw to fix it, while the film only needs to be heat-welded, etc. The film is easier in terms of securing the flexures. Also from the viewpoint of cost, the film is generally cheaper. However, in terms of the amount of displacement, although depending also on the shape of the rubber, in particular, the rubber is easier to obtain. The responsiveness required for the displacement also depends on, in particular, the shape of the rubber, but the rubber is generally better. In the self-sealing unit 4 which is a negative pressure generating means, a large displacement amount is not required, so a film is used in consideration of the bonding operation and the cost. In addition, as described later, the film is also preferable in that it absorbs the flow of ink resulting from the operation of the flow path opening / closing means 165. On the other hand, in order to shorten the time required for the purpose such as wiping, which is the purpose, the pressure control means 161 in the flow path and the flow path opening / closing means 165 respond when switching etc. when wiping etc. Better sex is preferable. In addition, it is generally preferable that the displacement amount be larger than that of the self-sealing unit 4 which is a negative pressure generating means. Therefore, rubber is used for the first and second flexible members 160 and 164.

  Further, in the present embodiment, while the negative pressure generating means is vertically disposed, the in-flow passage pressure adjusting means 161 and the flow passage opening / closing means 165 are horizontally disposed. That is, the self-sealing unit 4 is disposed such that the direction of displacement of the film serving as the flexible member of the self-sealing unit 4 serving as the negative pressure generating unit is perpendicular to the third direction Z, and The pressure in the flow passage is set such that the direction of displacement of the first flexible member 160 or the second flexible member 164, which is a flexible member of the flow passage pressure adjusting means 161 and the flow passage opening / closing means 165, is the third direction Z. The adjustment means 161 and the flow path opening / closing means 165 are disposed. The reason is as follows. In the case of vertical orientation, air bubbles may be trapped on the upper side by buoyancy. In the case of horizontal placement, the possibility of air bubbles being accumulated can be reduced. In addition, although the inlet / outlet of the flow path in the flow path opening / closing means 165 is on the lower side of the stacked flow path substrate 103, there is no problem because it is placed horizontally. In addition, the self-sealing unit 4 preferably has a larger pressure receiving area of the films 112 and 113, which is a flexible member, and is placed vertically without being placed horizontally, thereby achieving downsizing from the viewpoint of installation area and space. There is. As a comparative example, for example, when the self-sealing unit 4 is placed horizontally, in order to secure the pressure receiving area, it is necessary to change the layer with the pressure control means 161 in the flow path and the flow path opening / closing means 165 However, in this case, the dimension in the stacking direction (vertical direction) is increased. It should be noted that by sharing the layers from the self-sealing unit 4 to the flow path opening / closing means 165 among the colors of CMYK, the dimension in the stacking direction is reduced and the number of parts is also reduced.

  Furthermore, in the present embodiment, as shown in FIG. 2, the self-sealing unit 4 is disposed on both sides of the flow path member 5, and the in-flow path pressure adjusting means 161 and the flow path opening / closing means 165 Although it is disposed in the central portion, the flow path length between the self-sealing unit 4, 4 and the flow path opening / closing means 165, the dimension required for the flow path drawing, and the flow path opening / closing means 165 and the flow path It is possible to reduce the length of the flow passage between the inner pressure adjustment means 161 and the dimension required for the flow passage. As a comparative example, for example, both of the CMYK self-sealing units 4 are disposed on one side of the flow path member 5, and the flow path opening / closing means 165 of CMYK and the pressure adjustment means 161 in the flow path are disposed on the other side. When it is provided, the flow path length becomes long, which is not preferable from the viewpoint of pressure loss and air releasability. In addition, a flow passage communicating one self-sealing unit 4 and the flow passage member 5 with a flow passage communicating the other self-sealing unit 4 and the flow passage member 5 are arranged in the first direction X. In addition to the fact that the dimensions required for the routing become large as well, the size of the liquid discharge head 3 as a whole is not preferable.

  In this embodiment, the degree of pressurization by the pressure control means 161 in the flow path and the amount of buffer, the degree to which the pressure control means 161 in the flow path is pressurized is 1) the number of nozzles on the downstream side, 2) the degree of the hemispheric hemisphere, 2.) It depends on the compliance function in the reservoir and the pressure chamber in the discharge part 6A. As an example (but not necessarily limited to) the amount of change in the flow path volume by the flow path pressure adjustment means 161, it may be larger than the volume of the reservoir of the discharge part 6A. With this degree, pressurization can be performed effectively even if a large number of nozzles are provided for the reservoir.

  The amount of displacement of the first flexible member 160 is specified by the distance between the first flexible member 160 and the wall surface of the first recess 158 which is an ink chamber facing the first flexible member 160. That is, at the stage where the first flexible member 160 is displaced and abuts on the wall surface of the corresponding first concave portion 158, the target fluid is pressurized. As a result, compared to the case where the first flexible member 160 is displaced without limit, it becomes easy to apply pressure to a desired degree, and it is possible to prevent breakage of the rubber due to excessive application of pressure and the like. .

  In this embodiment, the flow path is closed by the flow path opening / closing means 165 before the flow path volume is changed by the flow path pressure adjusting means 161. However, the third concave portion 162 and the second Since the flexible member 164 is used, the channel volume and the pressure in the channel can also be varied by the channel opening and closing unit 165. Along with that, for example, the compliance of the meniscus pressure resistance and the reservoir, and the tension of the films 112 and 113 of the self-sealing unit 4 are appropriately set so that the ink does not flow from the nozzle opening. Specifically, the flow path resistance from the flow path opening / closing means 165 to the self sealing unit 4 which is a negative pressure generating means is made smaller than the flow path resistance from the flow path opening / closing means 165 to the nozzle opening. Thus, even if the flow path is closed by the flow path opening / closing means 165, the ink can be prevented from flowing from the nozzle opening.

  As shown in FIG. 9B, a groove 166 radially extended from the supply port 167 is provided on the upper surface in the first recess 158 which is the ink chamber of the flow passage pressure adjusting means 161 in the present embodiment. ing. This is because the first concave portion 158 which is the ink chamber of the in-flow path pressure adjusting means 161 is circular in cross section, and the ink flowing from the supply port 167 at the center of the circle is an arbitrary point on the arc from the center. It is because it flows out from the outlet 168 arrange | positioned in the direction. That is, the first flexible member 160, which divides the first recess 158 and the second recess 159 by pressurizing the in-channel pressure adjusting means 161 to the second recess 159 which is an air chamber which is an ink chamber, When the first flexible member 160 is bent toward the first concave portion 158 side, the rubber serving as the first flexible member 160 may block the fluid supply port depending on the amount of bending of the first flexible member 160. In addition, other than that, when suctioning in the sealed space provided by the cap to the surface of the nozzle opening and forcibly discharging the ink from the nozzle opening, the flow path is closed and the negative pressure is applied. Even in the suction), the rubber may block the supply port. Therefore, the supply port 167 on the ink chamber side of the flow path pressure adjusting means 161 is provided at the bottom of the groove 166 provided at the center of the circle, and the groove 166 is directed from the center of the circle to any point on the arc. By making it inlay, even if the first flexible member 160 is bent, the groove 166 secures the ink path as an ink flow path, and the path from the supply port 167 or the supply port 167 to the discharge port 168 is not blocked. It is like that.

  In consideration of the exhaustability in the first concave portion 158 which is the ink chamber, it is preferable that the direction in which the groove 166 extends is not on a straight line from the supply port 167 to the discharge port 168. If it is not on a straight line, the deflection of the first flexible member 160 changes the direction in which the ink flows in the first recess 158, and the air bubbles trapped in the first recess 158 before the flow changes are discharged by the flow change. It is easy to do.

  In particular, as shown in FIG. 4, the first flexible member 160 is urged from the first recess (ink chamber) 158 toward the second recess (air chamber) 159 in the flow passage pressure adjusting means 161. When the spring 203 is present, the first flexible member 160 in the in-flow path pressure adjusting means 161 is displaced toward the second recess (air chamber) 159 and is displaced toward the first recess (ink chamber) 158. It has a shape that can maintain the state. If a state of being displaced toward the first concave portion (ink chamber) 158 occurs during printing, the gap between the supply port 167 and the first flexible member 160 narrows, and the pressure loss increases. Therefore, it is desirable to provide a spring 203 that biases from the first recess (ink chamber) 158 side toward the second recess (air chamber) 159 side so as not to cause such displacement during printing. When rubber is used as the first flexible member 160 in the flow passage pressure adjusting means 161, it is preferable to use a bistable rubber in order to maintain a displaced state, and the second concave portion (air chamber) 159 When the side is open to the atmosphere (the default state), the biasing of the spring 203 can maintain the posture recessed toward the second recess (air chamber) 159 side. Further, instead of or together with the biasing of the spring 203, the second concave portion (air chamber) 159 may be suctioned or the like. Thus, the displacement of the first flexible member 160 during printing can be reliably suppressed.

  When the second recess (air chamber) 159 side is open to the atmosphere (the default state), the first flexible member 160 is recessed toward the second recess (air chamber) 159 side, and as a result, the first flexible member 160 is further biased. It is preferable to be in contact with the corresponding side surface on the 2 recessed portion (air chamber) 159 side. Thereby, the displacement of the first flexible member 160 during printing can be reliably suppressed as compared with the case where the first flexible member 160 is not in contact with anywhere.

  On the other hand, no spring is provided to bias the second flexible member 164 in the flow path opening / closing means 165. The reason is as follows. The in-flow path pressure adjustment means 161 and the flow path opening / closing means 165 are stacked and fixed by a common screw. At that time, if there are springs in both the in-flow path pressure adjustment means 161 and the in-flow path opening / closing means 165, assembly becomes difficult. Further, when using rubber as the second flexible member 164 of the flow path opening / closing means 165, unlike the first flexible member 160 in the pressure control means 161 in the flow path, it is preferable to use membrane-like rubber ( See Figure 12). As a result, it is possible to prevent the rubber in the second flexible member 164 in the flow path opening / closing means 165 from blocking the flow of ink in the flow path opening / closing means 165 without maintaining the displaced attitude. In comparison with that in the adjusting means 161, it can be made less likely to occur. Therefore, by not providing a spring for biasing the second flexible member 164 in the flow path opening / closing means 165, assembly can be facilitated.

  In the case where the flow path opening / closing means 165 and the in-flow path pressure adjustment means 161 are arranged on the same plane, no difficulty in assembly occurs, so the second flexible member 164 in the flow path opening / closing means 165 is used. A biasing spring may be provided. Thereby, the displacement of the second flexible member 164 during printing can be suppressed. Further, instead of or together with the biasing of the spring, the fourth concave portion (air chamber) 163 side may be suctioned or the like.

  When releasing the negative pressure, the first flexible member 160 in the in-flow path pressure adjusting means 161 needs to reduce the volume in the first recess 158 (ink chamber). Therefore, as shown in FIG. 11, the displacement amount is larger than that of the second flexible member 164 in the flow path opening / closing unit 165. Specifically, the thickness on the side of the arc is thinner than the thickness of the central portion of the circle, and the amount of displacement is increased by bending the thinned portion in the displacement direction. In addition, since it is desired to switch the rubber posture in two stages, the case where it is desired to release the negative pressure and the case where it is not so, it is possible to stably switch the rubber posture by using a so-called bistable rubber.

  The second flexible member 164 of the flow path opening / closing means 165 may not be a so-called bi-stable rubber, but may be a film-like rubber as shown in FIG. In order to arrange so-called bi-stable rubber, the installation area is required to be larger than that of a film-like rubber, but by making the second flexible member 164 of the flow path opening / closing means 165 a film-like rubber, The installation area required for the road opening / closing means 165 can be reduced. In this embodiment, as shown in FIG. 2, the flow path substrate 102 is smaller than the flow path substrate 103 in the fifth direction Ya, and the self-sealing unit 4 is disposed on both sides of the flow path opening / closing means 165 It is like that. That is, in the third direction Z, the self-sealing unit 4 is disposed at the same stacking position as at least one of the flow path substrates 102 and 103 forming the flow path opening / closing means 165. Thereby, the liquid discharge head 3 is miniaturized.

  With regard to the distribution of the air flow path, in the present embodiment, the third concave portion 162 which is an ink chamber in the flow path opening / closing means 165 and the first concave portion 158 which is an ink chamber in the flow path pressure adjusting means 161 It is necessary to provide for each color. If not provided, on the premise that the wiping timing for the nozzle surface is switched for each type of ink, the inside of the third recess 162 which is the ink chamber in the flow path opening / closing means 165 and the pressure adjustment means 161 in the flow path An ink flow path switching mechanism is required to switch the type of ink to be supplied to the first concave portion 158 which is the ink chamber. On the other hand, the third concave portion 162 in the flow path opening / closing means 165 and the first concave portion in the flow path pressure adjusting means 161 share the air for displacing the first and second flexible members 160 and 164. , It is not necessary to provide for every kind (color) of ink.

  Therefore, the third concave portions 162 in the flow path opening / closing means 165 provided for each type of ink may be communicated by an air flow path or may be a common air chamber. Similarly, the first recesses 158 in the in-flow path pressure adjusting means 161 provided for each type of ink may be in communication or may be a common air chamber. However, in the case of using a common air chamber, the volume increases, so the effect of pressurizing air becomes smaller than the pressure receiving area of the flexible member. On the other hand, when the air chamber is provided for each type of ink, the volume of the air chamber does not become too large, so the effect of pressurization does not decrease.

  When the negative pressure release operation is performed, 1) the flow path is closed by the displacement of the second flexible member 164 in the flow path opening / closing means 165, and then 2) the pressure in the flow path pressure adjusting means 161 (1) Since it is necessary to reduce the flow path volume by the displacement of the flexible member 160, the fourth recess 163 in the flow path opening and closing means 165 and the second recess 159 in the flow path pressure adjusting means 161 are common air chambers. It can not be. Further, in the case where the air chambers communicate with each other, an air flow path switching mechanism is required.

  The operation of the flow path opening / closing means 165 is performed by switching between pressurization and pressure reduction of the fourth concave portion (air chamber) 163 in the flow path opening / closing means 165. When the flow path of the third recess (ink chamber) 162 in the flow path opening / closing means 165 is closed, pressure is applied. When releasing the blockage, open the air. Note that in order to accelerate the response of the flow path opening and closing, in addition to (in place of) opening to the atmosphere, the blocking may be canceled by reducing the pressure.

  In addition, if the nozzle opening surface is capped (sealed) with a cap and the inside of the enclosed space is made negative by the suction of a suction pump provided on the cap side and ink in the head is forcibly discharged, it is not necessary to choke Depressurize. Apply pressure if you want to choke. When suction is performed in a choked state, negative pressure is stored in the head main body 6, and air bubbles stagnated in the flow path upstream of the filter portion 6B1 of the filter means 6B provided downstream of the flow path opening / closing means 165 , Can be discharged through the filter.

  With regard to the second flexible member 164 of the flow path opening / closing means 165, when the second flexible member 164 for each type of ink is on the same plane, the second flexible member 164 for each type of ink is It can be a member. That is, one flexible member may have a size necessary for the number of types of ink. Further, the same applies to the first flexible member 160 of the pressure control means 161 in the flow path. Further, on the plane on which the flexible member in the flow path opening / closing means 165 and the flow path pressure adjustment means 161 is provided, the ink flow path supplied to the flow path opening / closing means 165 and the flow path pressure adjustment means 161 is also disposed. It is done. Since the ink flow path and the flow path opening / closing means 165 and the flow path pressure adjustment means 161 are formed of the same members and these members are laminated, the ink flow path is formed on the plane on which the flexible member is provided. It is divided. An O-ring may be used to seal the divided ink flow path, but the O-ring may also be provided as a single member with the rubber in the flow path opening / closing means 165 or the pressure control means 161 in the flow path .

  Although the case where the self-sealing unit 4 is used as the negative pressure generation means has been described in the above embodiment, the negative pressure generation mode may use the negative pressure in the cartridge other than this, and the head may be used. A water head pressure difference may be used in which the position of the tank in which the main body 6 and the flow path are in communication with each other is adjusted with respect to the head main body 6. The point is that it can be configured so that the inside of the liquid flow path of the head body 6 has a negative pressure.

(Another embodiment of the flow path opening / closing means 165)
As shown in FIG. 13 as another embodiment of the recording apparatus 100 and the flow path opening / closing means 165 of the liquid discharge head 3 according to the above-described embodiment, it is useful. Such flow path opening / closing means will be described based on the drawings. In the drawings, the same parts as those in FIGS. 1 to 11 are denoted by the same reference numerals, and redundant description will be omitted.

  FIG. 13 is a schematic configuration view schematically showing the flow path opening / closing means. As shown in the figure, the flow path opening / closing unit 165A according to the present embodiment includes a third recess 162A, a fourth recess 163A, and a second flexible member 164A. Here, the third concave portion 162A communicates with the head main body 6 (see FIG. 2) to store the ink. The fourth concave portion 163A communicates with the fluid supply source (not shown) for supplying air, which is a fluid for operating the flow path opening / closing means 165A, via the air flow path 171A to store air, Opposite the recess 162A. The second flexible member 164A is formed of rubber or the like, which is interposed between the third recess 162A and the fourth recess 163A to seal the third recess 162A and the fourth recess 163A. It is a member. More specifically, the second flexible member 164A seals a space on the central portion side via the seal portion 164A1 to form a fourth concave portion 163A which becomes an air chamber. Here, the lower end portion of the air flow path 171A is open at the central portion of the fourth concave portion 163A.

  Thus, when pressurized air is supplied to the fourth concave portion 163A, which is a sealed space, via the air flow path 171A, the central portion of the second flexible member 164A in the third direction Z from the Z1 side is Z2 It is pressed and deformed to the side, and it abuts on the opening of the flow path 152A in a state as shown by a two-dot chain line in FIG. 13C to close the flow path 152A. As a result, at the normal time when the flow path opening / closing means 165A is in the open state, the flow of ink from the flow path 151A to the head main body 6 (see FIG. 2) is stopped from the flow path 151A via the third concave portion 162A. Chalk suction is performed in this state.

  Here, in the present embodiment, an annular space 165A1 is provided around the second flexible member 164A to ensure a predetermined deformation of the second flexible member 164A, but this is not always necessary. is not.

  Furthermore, in the present embodiment, the volume of the fourth recess 163A is smaller than that of the third recess 162A. As described above, by relatively reducing the volume of the fourth concave portion 163A, it is possible to reduce the fluctuation of the flow path volume accompanying the opening and closing of the flow path opening / closing means 165A. In particular, when suction is performed in the flow path with the flow paths 151A and 152A closed by the flow path opening / closing means 351 (see FIG. 1) provided on the supply side (the ink cartridge 350 (see FIG. 1) side), In order to prevent the second flexible member 164A from closing the flow path due to the negative pressure, the pressure in the third recess 162A is reduced and the second flexible member 164A is kept in contact with the third recess 162A. There is. That is, there is a case where suction is performed in a state of being in contact, but even in that case, if the volume of the fourth concave portion 163A is small, the flow path between the pressure reduction in the third concave portion 162A and its release. Volume variations can be reduced.

  Moreover, the convex part 200 is formed in the 4th recessed part 163A in a present Example in the position contact | abutted with the 2nd flexible member 164A. This will be described with particular reference to FIG. 13 (a). FIG. 13A shows the ceiling portion of the fourth concave portion 163A as viewed from the Z2 side with respect to the third direction Z, as viewed from the Z2 side. As shown in the figure, the convex portion 200 is an annular portion projecting from the ceiling portion of the fourth concave portion 163A to the Z2 side in the third direction in the third direction, and a plurality of concentrically arranged In the example, it consists of 4).

  By providing the convex portion 200 in this manner, the second flexible member 164A can be made to abut on the convex portion 200 to regulate the position of the second flexible member 164A. The position of the second flexible member 163A of the fourth concave portion at the time of normal pressure and at the time of pressure reduction can be made the same while preventing continuous sticking to the ceiling portion of the fourth concave portion 163A.

  In the present embodiment, the concentric convexes 200 are not limited to such a structure. If the position of the surface of the second flexible member 164A can be regulated at normal times, no further limitation is necessary. For example, a structure may be employed in which a large number of independent convex portions are provided on the ceiling portion of the fourth concave portion 163A.

(Other Embodiments of Liquid Ejection Head)
FIG. 14 is a schematic configuration view schematically showing the liquid discharge head according to the present embodiment. As shown in the figure, the liquid discharge head unit 1A according to the present embodiment has a plurality of liquid discharge heads 3A and a plurality of in-flow-path pressure adjusting means 161A respectively communicating with each head main body 6 . Each flow path pressure adjustment means 161A displaces the first flexible member 160A by pressurized air supplied to the second concave portion 159 via the air flow path 172A, which will be described in detail later, accompanied by this. The pressure in the channels 152A and 153A is increased by the change in volume of the first recess 158A to release the negative pressure state. The suction means 16 exerts a negative pressure on the discharge part 6A of each head main body 6 to suck the ink in the head main body 6 to discharge the air bubbles.

  One air supply source 352 for supplying pressurized air to each of the flow path pressure adjusting means 161A via the air flow path 172A is configured to supply air of a predetermined pressure by itself. That is, in the present embodiment, one air supply source 352 is shared for each of the in-flow-path pressure adjusting means 161A.

  Therefore, in comparison with the configuration provided with a pressure source such as air supply source 352 for each negative pressure release mechanism consisting of a self-sealing unit (see FIGS. 1 and 3; the same applies hereinafter), the configuration should be simplified. Can.

  The supply amount and pressure of the air supplied from the air supply source 352 in the present embodiment are the in-flow path pressure adjusting means 161A having the most severe negative pressure release condition (to be described in detail later) among the plurality of in-flow path pressure adjusting means 161A. It is adjusted to the negative pressure release condition of. That is, when the pressure in each flow path 153A is adjusted by all the flow path pressure adjustment means 161A, the pressure adjustment means in each flow path from the discharge part 6A corresponding to all the flow path pressure adjustment means 161A With the change in volume at 161A, the ink is ejected.

  Thus, even if the displacement volume required for negative pressure release differs depending on the negative pressure release mechanism such as the self-sealing unit 4 or the corresponding head main body 6, the negative pressure release mechanism or head main body having a small required displacement volume The displacement volume can be reliably formed to such an extent that the negative pressure can be reliably released to all the negative pressure release mechanisms and the head main body 6 while permitting the discharge of the liquid from 6. As a result, it is possible to reliably release the negative pressure. That is, when the negative pressure release operation is performed by driving the pressure control means 161A in each flow path under the above conditions, there is a possibility that the discharge part 6A from which the ink is discharged, but all of them are all The negative pressure can be reliably released by the head body 6 of the above. Here, in the present embodiment, the ejected ink is collected by the cap of the suction means 16 so as not to contaminate the floor surface of the apparatus main body 2.

  Also in the liquid discharge head 1A according to the present embodiment, although not shown, the flow path opening / closing means 165 (see FIG. 2) communicating with each flow path 152A is on the upstream side of each flow path pressure adjustment means 161A. It is arranged.

  Next, the configuration of the flow path pressure adjusting means 161A will be described in detail. The in-flow-path pressure adjusting means 161A includes a first recess 158A, a second recess 159A, and a first flexible member 160A. The first concave portion 158A communicates with the head main body 6 to store the ink. The second concave portion 159A is in communication with an air supply source 352 for supplying air, which is a fluid for operating the flow passage pressure adjusting means 161A, via the air flow passage 172A. Thus, the air is stored, and is opposed to the first recess 158A via the first flexible member 160A. The first flexible member 160A is a disk formed of a flexible member such as rubber which is interposed between the first recess 158A and the second recess 159A and seals the first recess 158A and the second recess 159A. Shaped members. The first flexible member 160A is always urged toward the second recess 159A by a spring 203A which is an urging means. As a result, normally, the volume of the first recess 158A, that is, the volume of the in-flow passage pressure adjusting means 161A is maximized. On the other hand, the lower end portion of the air flow path 172A is open at the central portion of the second concave portion 159A. Thus, when pressurized air is supplied to the second concave portion 159A, which is a sealed space, via the air flow path 172A, the first flexible member 160A resists the spring force of the spring 203A in the third direction Z. In this case, it is pressed from the Z1 side to the Z2 side to be deformed. As a result, the volume of the first recess 158A is reduced, the ink in the flow path 153A communicating with the head main body 6 is pressurized, and the negative pressure in the flow path 153A is released.

  Such negative pressure release conditions differ depending on the pressure control means 161A in each flow path. That is, the displacement volume in the first recess 158A necessary for releasing the negative pressure in the flow passage pressure adjustment means 161A, and the pressure amount from the air supply source 352 for realizing it are 1) self-sealing unit 4 ( 1) and 3) etc.) and the corresponding performance in the initial state such as the influence of compliance in the head main body 6, 2) the amount of air bubbles in the liquid discharge head 3A is determined as the main parameter Be done. Therefore, in the present embodiment, the worst condition for releasing the predetermined negative pressure is obtained by the in-channel pressure adjusting means 161A, and the volume and air pressure of the first recess 158A that can perform the predetermined negative pressure release even under this worst condition It is decided.

  More specifically, among these, the maximum bubble amount can be identified by calculation and measurement. Also, the performance of the negative pressure release mechanism such as the self-sealing unit 4 can be specified by the standard and the actual measurement. Therefore, even under the worst condition specified by calculation, specification and measurement, the first flexible member 160A is deformed until the first flexible member 160A adheres to the inner circumferential surface of the first recess 158A in consideration of the elongation of the first flexible member 160A. While determining the volume of the recess 158A, the pressure of air is determined.

  FIG. 15 is a graph showing the characteristics of the in-flow path pressure adjusting means 161A. FIG. 15A is a graph showing the internal pressure of the liquid ejection head 3A with respect to the excluded volume of the ink in the first recess 158A in the case where air bubbles exist It shows the relationship. In the figure, ■ indicates no bubbles (measured), and ◇ indicates a maximum amount of bubbles. Referring to the figure, the slope of the internal pressure correlation between the displacement volume and the liquid ejection head 3A is changed according to the size of the bubble in the liquid ejection head 3A, and the inclination becomes smaller as the bubble amount increases. I understand that Therefore, the amount of air bubbles used is that specified by whiteout ◇. Further, (b) shows the relationship between the internal pressure of the liquid discharge head 3A and the excluded volume of the ink in the first recess 158A due to the difference in the initial negative pressure in the self-sealing unit 4. In the figure, the initial values decrease in the order of ■, ◇, ●, and ○. Referring to the figure, it can be seen that the initial value of the internal pressure of the liquid discharge head 3A determines the intercept of the internal pressure correlation of the excluded volume-liquid discharge head 3A. Therefore, the characteristic of ○ is used as the worst condition.

  Using these parameters, the maximum value of the volume fluctuation of the first concave portion 158A which can release the negative pressure even under the worst condition is determined, and the air pressure that can realize the volume fluctuation is determined as described above. Here, in order to uniformly apply the air pressure in each flow path pressure adjustment means 161A, in the present embodiment, as described above, each liquid discharge head 3A is added from one air supply source 352 via the air flow path 172A. It has a supply system that can be pressed. Here, the volume variation of one first flexible member 160A is deformed until it sticks to the inner peripheral surface of the first concave portion 158A in consideration of the spread of the rubber which is the material.

(Other Embodiments of Liquid Ejection Device)
FIG. 16 is a schematic configuration view schematically showing a liquid discharge apparatus according to another embodiment of the present invention. As shown in the figure, the liquid ejection apparatus 100A according to the present embodiment includes a liquid ejection head including an ink cartridge 350 which is a liquid supply source, and a flow path opening / closing means 165 which is a first flow path opening / closing means. 3B and suction means 16. The other mechanisms are not shown. Here, the on-off valve 351, which is the second on-off means, is disposed between the flow path 352 connected to the outlet side of the ink cartridge 350 and the flow path 151 leading to the inlet side of the flow path opening-closing means 165. ing. That is, the on-off valve 351 opens and closes between the flow path 352 and the flow path 151 on the upstream side (the ink cartridge 350 side) of the flow path opening / closing unit 165.

  The flow path opening / closing unit 165 is disposed between the flow path 151 and the flow path 152 extending from the flow path opening / closing valve 165 to the head main body 6. Further, the flow path opening / closing means 165 is an open / close valve having the same configuration as that shown in FIG. 2 or 4. That is, the second flexible member 164 is moved from the Z2 side in the third direction Z to the Z1 side by pressurized air supplied to the fourth concave portion 163 via the air flow path 171, whereby the flow paths 151 and 152 are obtained. The pressure between the flow channels 151 and 152 is opened to allow the flow of ink from the flow channel 151 to the flow channel 152 by closing the space between the flow channels 151 and 152 and releasing the pressure and reducing the pressure.

  Thus, in the present embodiment, under the control of the control device 17, the flow path 152 is opened by the flow path opening / closing means 165, and the flow is drawn in the first mode of suction by the suction means 16 with the flow path 352 closed by the opening / closing valve 351; With the flow path 151 closed by the path opening / closing means 165, operations in the second mode of suctioning by the suction means 16 are respectively performed.

  Thus, according to the present embodiment, suction in the first mode and the second mode, that is, choke suction can be appropriately performed at a desired timing. Incidentally, in the first mode, the ink on the downstream side of the on-off valve 351 is sucked, and in the second mode, the ink on the downstream side of the flow path opening / closing unit is sucked. Therefore, in the second mode, the desired air bubbles can be exhausted with a small ink consumption. At the same time, since the distance of the flow path is short, a larger negative pressure can be applied to the inside of the head body 6, so that good evacuation can be realized. Further, by performing the suction in the first mode and then performing the suction in the second mode at the time of the initial filling, it is possible to improve the exhaustability at the time of the initial filling. Further, wasteful disposal of the liquid accompanying the suction operation can be reduced as much as possible by performing not only suction during initial filling but also air discharge during printing operation thereafter by execution of the first mode.

  Furthermore, in the operation of the first mode, the flow path opening / closing means 165 can be controlled to keep the flow path 151 open. In this case, the fourth concave portion 163 filled with the air of the flow path opening / closing means 165 is pressurized when the flow path 151 is closed, on the premise that any of air release, pressure reduction and pressure can be performed. 2) When the flow path 151 is opened, the air is released or depressurized. 3) When suctioning from the discharge unit 6A, the depressurization is performed. In particular, as an effect in the case of 3), there is a possibility that the second flexible member 164 may unintentionally close the flow path 151 due to the suction from the discharge part 6A. You can prevent.

  In the above-described embodiment, the liquid discharge device includes the pair of rails 11A and 11B and the cleaning unit 14. However, the present invention is not limited to this, and the liquid discharge head unit 1 may be provided. In addition, the head main body 6 may be provided with a pressure generating chamber and pressure generating means for causing pressure fluctuation in ink in the pressure generating chamber.

  Further, in order to open and close the flow path, the flow path opening / closing means 165 displaces the second flexible member 164 to close or open the ink flow path of the third concave portion 162, thereby adjusting the pressure in the flow path. Although the volume fluctuation in the flow path by the means 161 is not absorbed on the upstream side of the flow path opening / closing means 165, it is not limited thereto. That is, if the volume fluctuation in the flow path by the flow path pressure adjusting means 161 can not be absorbed on the upstream side of the flow path opening / closing means 165, the liquid flow path is not completely blocked by the opening / closing by the flow path opening / closing means 165. It suffices, for example, to be able to switch between a state where the flow path resistance between the flow path pressure adjustment means 161 and the negative pressure generation means is small and a large state by opening and closing by the flow path opening and closing means 165. As a result, the pressure loss during printing can be reduced, and the volume fluctuation in the flow path by the flow path pressure adjustment means 161 can be prevented from being absorbed upstream of the flow path opening / closing means 165. That is, closing the flow path by the flow path opening / closing means 165 includes not only the case where the flow path is completely closed but also the case where the flow path resistance of the flow path is switched from a small state to a large state. The same applies to the case where the flow path opening / closing means 165 is used to reduce the overall volume in the flow path with respect to the volume fluctuation caused by the flow path pressure adjustment means 161.

  Further, in the above embodiment, a so-called line type recording apparatus in which the liquid discharge head unit 1 is fixed to the apparatus main body 2 and printing is performed only by conveying the recording sheet S is exemplified as the inkjet type recording apparatus 100. The invention is not particularly limited thereto, and the liquid discharge head 3 is mounted on a carriage that moves in a direction crossing the first direction X, which is the conveyance direction of the recording sheet S, for example, in the second direction Y, The present invention can also be applied to a so-called serial type recording apparatus in which printing is performed while moving the head 3 in a direction intersecting the transport direction.

  Furthermore, in the above-described embodiment, the present invention has been described by exemplifying an ink jet recording head that discharges ink droplets, but the present invention is intended for a wide range of liquid discharge heads in general. As a liquid discharge head, for example, a recording head used for an image recording apparatus such as a printer, a color material injection head used for manufacturing a color filter such as a liquid crystal display, an electrode formation such as an organic EL display or FED (field emission display) Electrode material jet head used in the above, a bio-organic matter jet head used in biochip manufacture, and the like.

  DESCRIPTION OF SYMBOLS 1 liquid discharge head unit, 2 apparatus main body, 3 liquid discharge head, 4 self-sealing unit, 5 flow path member, 6 head main body, 18 distribution units, 100 recording device, 101, 102, 103, 104, 105 flow path substrate , 112, 113 film, 120, 121 valve body, 130, 131 flow passage, 151, 152, 153 flow passage, 158 first recess, 159 second recess, 160 first flexible member, 161 in-flow passage pressure adjusting means , 162 third concave portion, 163 fourth concave portion, 164 second flexible member, 165 flow path opening / closing means, 171, 172 air flow path

In view of the circumstances as described above, the present invention not only can reduce the volume of the flow path to be released in releasing the negative pressure easily and effectively but also to the normal state after releasing the negative pressure. It aims to also recovery provides a smooth liquid discharging head and a liquid discharge equipment can perform.

Claims (13)

A liquid discharge head comprising: a discharge unit that discharges a liquid supplied from a liquid supply source via a flow path member through a nozzle opening by driving of a drive element,
Negative pressure generating means in communication with the discharge unit to maintain the negative pressure of the discharge unit;
An in-flow-path pressure adjusting means, located in the middle of the flow path between the negative pressure generating means and the discharge unit, changing the volume of the flow path to adjust the pressure in the flow path;
A flow path opening / closing means located in the middle of the flow path between the negative pressure generating means and the pressure control means in the flow path and opening / closing the flow path,
When the inside of the flow path is pressurized by the pressure control means in the flow path, the flow path is closed by the flow path opening / closing means prior to pressurization;
When the inside of the flow path is pressurized by the pressure control means in the flow path, after the flow path is opened by the flow path opening / closing means, the pressure in the flow path is reduced by the pressure adjustment means in the flow path. Liquid discharge head. In the liquid discharge head according to claim 1,
The volume of the pressure control means in the flow path is larger than the volume of the flow path opening / closing means. The liquid discharge head according to claim 1 or 2,
The volume of the pressure control means in the flow path and the volume of the flow path opening / closing means are adjusted by the amount of displacement of the flexible members respectively possessed by the pressure control means in the flow path and the flow path opening / closing means.
Further, the displacement amount of the flexible member included in the flow passage pressure adjusting unit is larger than the displacement amount of the flexible member included in the flow passage opening / closing unit. The liquid discharge head according to any one of claims 1 to 3.
The negative pressure generating means has a flexible member displaced by the negative pressure, and
A liquid discharge head characterized in that a flexible member included in the negative pressure generation means is more easily bent than a flexible member included in the in-flow path pressure adjustment means. The liquid discharge head according to any one of claims 1 to 4.
The flow path opening / closing means is
A third recess communicating with the discharge portion to store liquid;
A fourth recess communicating with a fluid supply source for supplying a fluid for operating the flow path opening / closing means to store fluid and facing the third recess;
A second flexible member interposed between the third recess and the fourth recess to seal the third recess and the fourth recess;
Equipped with
Further, a volume of the fourth concave portion is smaller than that of the third concave portion. In the liquid discharge head according to claim 5,
The liquid discharge head according to claim 1, wherein the fourth concave portion has a convex portion at a position in contact with the second flexible member. The liquid discharge head according to any one of claims 1 to 6.
There are a plurality of sets of the pressure control means in the flow path, the flow path opening / closing means, and the discharge part,
The fluid pressure for driving the plurality of sets of in-flow-path pressure adjusting means is supplied from a common fluid source to the plurality of sets of in-flow-path pressure adjusting means, so that the pressure in all sets of in-flow channels is supplied. A liquid discharge head characterized by adjusting the pressure in each of the flow paths by adjusting means.   A liquid discharge apparatus comprising the liquid discharge head according to any one of claims 1 to 7. In the liquid discharge apparatus according to claim 8,
After wiping the nozzle surface of the discharge portion of the liquid discharge head, the flow path opening / closing means opens the flow path, and the control means controls the pressure in the flow path to reduce the pressure in the flow path. Liquid discharge device characterized by A liquid discharge apparatus including a discharge unit that discharges a liquid supplied from a liquid supply source through a flow path member through a nozzle opening by driving of a drive element,
First flow path opening / closing means provided in the middle of the flow path between the liquid supply source and the discharge unit, which opens and closes the flow path;
Second flow path opening / closing means provided in the middle of the flow path between the liquid supply source and the first flow path opening / closing means, for opening / closing the flow path;
And suction means for suctioning the liquid in the flow path from the discharge portion;
A first mode in which suction is performed by the suction unit in a state in which the flow channel is opened by the first flow channel opening / closing unit and the flow channel is closed by the second flow channel opening / closing unit;
A second mode in which suction is performed by the suction unit in a state where the flow channel is closed by the first flow channel opening / closing unit;
Perform each action of
A liquid discharge apparatus characterized by performing the second mode of operation after the first mode of operation. In the liquid discharge apparatus according to claim 10,
A liquid ejection apparatus characterized in that the frequency of performing the operation of the second mode is higher than the frequency of performing the first mode. In the liquid discharge apparatus according to claim 10 or 11,
A liquid discharge apparatus characterized in that, in the operation of the first mode, the first channel opening / closing means keeps the channel open. It is a liquid discharge head provided with a discharge part which discharges a liquid supplied from a liquid supply source via a flow path member through a nozzle opening by driving of a drive element, and it communicates with the discharge part, and the discharge part A negative pressure generating means for maintaining the negative pressure, and a flow for adjusting the pressure in the flow path by changing the volume of the flow path in the middle of the flow path between the negative pressure generating means and the discharge part A control method of a liquid discharge head, comprising: in-path pressure adjusting means; and an in-flow path opening / closing means located in the middle of a flow path between the negative pressure generating means and the in-flow path pressure adjusting means. There,
A first step of pressurizing the inside of the flow path by the pressure control means in the flow path after closing the flow path by the flow path opening / closing means;
When the inside of the flow path is pressurized by the pressure control means in the flow path, after the flow path is opened by the flow path opening / closing means, the pressure in the flow path is reduced by the pressure adjustment means in the flow path And controlling the liquid discharge head.

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