JP7014513B2 - Liquid injection head and liquid injection device - Google Patents

Description

The present invention relates to a liquid injection head and a liquid injection device.

Conventionally, there is an inkjet printer provided with an inkjet head as a device for ejecting droplet-shaped ink onto a recording medium such as recording paper and recording an image or characters on the recording medium. The inkjet head is configured by mounting, for example, a plurality of head modules corresponding to each color on a carriage.

The head module described above is configured by mounting a head chip that ejects ink, a manifold in which an ink flow path for supplying ink to the head chip is formed, and a drive board that drives the head chip on a base member (for example). , The following Patent Document 1).
In Patent Document 1, the base member includes a horizontal base extending in the scanning direction of the inkjet head and a vertical base erected from the horizontal base.
The head chip and drive board are supported, for example, on a vertical base. As a result, the heat generated in the head chip and the drive board is dissipated through the vertical base and the like. On the other hand, the manifold is arranged on the base member on the side opposite to the vertical base with the head chip sandwiched in the scanning direction of the inkjet head.

JP-A-2015-120265

By the way, in the inkjet printer, there is still room for improvement in keeping the ink temperature at the time of ejection in a desired temperature range. When the ink temperature at the time of ejection varies, the viscosity of the ink varies, and as a result, the amount of ink ejected, the ejection speed, and the like change. As a result, desired printing characteristics may not be obtained.

The present invention has been made in consideration of such circumstances, and an object of the present invention is to provide a liquid injection head and a liquid injection device having excellent printing characteristics.

The liquid injection head according to one aspect of the present invention includes a head tip having a channel filled with a liquid, a manifold that supports the head tip and has a liquid flow path communicating with the channel, and the manifold. It is supported and provided with a heating mechanism for heating the liquid in the liquid flow path. The manifold includes an inflow port that communicates with the liquid flow path and allows the liquid to flow into the liquid flow path, and a communication portion that communicates the liquid that has flowed through the liquid flow path so as to supply the head chip. A flow path member having a first surface on which the head tip is supported is provided . The liquid flow path is formed so as to meander and extend from the inflow port toward the communication portion, and also penetrates the flow path member in the normal direction of the first surface and has a plurality of the above. It has a communication opening that communicates collectively with the channel. The communication opening is closed by a film member arranged on a second surface of the flow path member facing away from the first surface in the normal direction, and the film member is closed by the flow path member. Is placed at a position facing the head chip with the head chip in between.

According to this configuration, since the liquid flow path meanders and extends, heat transfer between the liquid and the manifold is compared with the case where the liquid flow path is formed linearly from the upstream end to the downstream end. The area can be increased. Therefore, the heat of the heating mechanism can be effectively transferred to the liquid in the liquid flow path. As a result, the liquid can be supplied to the head tip at a desired temperature (viscosity), so that the liquid temperature at the time of injection can be maintained within a desired range. As a result, it is possible to suppress variations in the injection amount and injection speed of the liquid and obtain excellent printing characteristics.
Further, since the communication opening penetrates the flow path member in the normal direction, the size of the manifold is reduced in the normal direction of the first surface of the manifold as compared with the case where the liquid flow path is formed in a groove shape. Therefore, it becomes easy to secure the volume of the communication opening. By securing the volume of the communication opening, it becomes easier to buffer the pressure fluctuation in the head chip in the communication opening, so that so-called crosstalk (pressure fluctuation in the channel is propagated to other channels through the communication opening or the like). The phenomenon) can be suppressed.

In the above aspect, the heating mechanism may be a heater.
According to the above aspect, since the liquid flowing in the liquid flow path is also heated by the heater, the liquid can be reliably supplied to the head chip at a desired temperature.

In the above embodiment, the heating mechanism may be a drive substrate electrically connected to the head chip.
According to the above aspect, the liquid can be heated by utilizing the waste heat of the drive substrate. As a result, the power consumption required for heating the liquid can be reduced as compared with the case where the liquid is heated by the heater.
Further, since the heat generated in the drive board is effectively dissipated to the liquid flowing through the manifold and the liquid flow path, it is possible to suppress the temperature of the drive board from becoming high.

In the above embodiment, at least the inner surface of the liquid flow path of the manifold may be formed with a coating film having corrosion resistance to the liquid.
According to the above aspect, since the coating having corrosion resistance is formed on the inner surface of the liquid flow path, it is possible to suppress corrosion of the manifold due to the liquid and improve the durability.

In the above embodiment, the liquid flow path may have a main flow path and a liquid reservoir that communicates with the main flow path and stores the liquid.
According to the above aspect, since the liquid flowing through the liquid flow path is temporarily stored in the liquid pool, the heating time of the liquid can be secured. As a result, the liquid can be supplied to the head tip at a desired temperature (viscosity), so that the liquid temperature at the time of injection can be maintained within a desired range. As a result, excellent printing characteristics can be obtained.

In the above aspect, the film member may have flexibility.
According to the above aspect, the film member bends and deforms according to the pressure fluctuation in the head tip. This makes it possible to buffer the pressure fluctuation in the head tip. For example, the decrease in volume of the channel with the injection of liquid causes a momentary decrease in pressure in the channel. Then, the pressure fluctuation in the channel becomes a pressure wave and propagates in the communication opening, and the film member bends and deforms. That is, the film member bends and deforms so as to reduce the volume of the communication opening. As a result, the pressure fluctuation generated in the channel can be buffered by the communication opening. Further, by cushioning the pressure fluctuation with the film member, the above-mentioned crosstalk can be suppressed. As a result, the printing characteristics can be improved.

In the above aspect, the manifold may include a film retainer that holds the film member in the normal direction with the flow path member.
According to the above aspect, by sandwiching the film member between the film retainer and the flow path member in the normal direction, peeling or damage of the film member can be suppressed, and durability can be improved.

In the above embodiment, in the film retainer, a clearance hole that allows bending and deformation of the film member is formed at a position overlapping the communication opening when viewed from the normal direction, and the method of the opening edge of the clearance hole. A chamfered portion may be formed at a portion facing the film member in the linear direction.
According to the above aspect, since the chamfered portion is formed in the portion of the opening edge of the clearance hole facing the film member in the normal direction, the film member and the corner portion of the film retainer interfere with each other when the film member is bent and deformed. Can be suppressed. As a result, damage to the film member can be suppressed and durability can be improved.

In the above aspect, the second surface of the flow path member may be formed with a recess in the normal direction and a storage recess for accommodating the film member and the film retainer.
According to the above aspect, since the accommodating recess is formed in the flow path member, the accommodating recess can be used as a guide when the film member or the film retainer is attached to the flow path member. This makes it possible to improve the positioning accuracy and the assembly efficiency of the film member and the film retainer.
Further, since the amount of protrusion of the film member and the film retainer from the second surface of the flow path member can be suppressed, the size of the manifold can be reduced in the normal direction of the first surface of the manifold.

The liquid injection device according to one aspect of the present invention includes the liquid injection head according to the above aspect.
According to the above aspect, it is possible to provide a liquid injection device having excellent printing characteristics.

According to one aspect of the present invention, it is possible to provide a liquid injection head and a liquid injection device having excellent printing characteristics.

It is a schematic block diagram of the inkjet printer which concerns on 1st Embodiment. It is a perspective view of the inkjet head which concerns on 1st Embodiment. It is a perspective view which shows the state which a part of the inkjet head which concerns on 1st Embodiment is removed. It is a perspective view of the 1st head module which concerns on 1st Embodiment. It is an exploded perspective view of the head tip which concerns on 1st Embodiment. It is an exploded perspective view of the manifold which concerns on 1st Embodiment. It is an exploded perspective view of the base member, the nozzle plate and the nozzle guard which concerns on 1st Embodiment. FIG. 3 is a partial bottom view of the inkjet head according to the first embodiment as viewed from the −Z direction. It is a front view of the flow path member which concerns on 2nd Embodiment. It is sectional drawing corresponding to the X-ray line of FIG. It is sectional drawing corresponding to the X-ray line of FIG. It is a perspective view of the manifold which concerns on 3rd Embodiment. It is sectional drawing corresponding to the XIII-XIII line of FIG. It is a perspective view of the manifold which concerns on 3rd Embodiment. It is a front view which looked at the manifold which concerns on 3rd Embodiment from the + Y direction. It is sectional drawing corresponding to the XVI-XVI line of FIG. It is a perspective view of the manifold which concerns on the modification of embodiment.

Hereinafter, embodiments according to the present invention will be described with reference to the drawings. In the following embodiment, an inkjet printer (hereinafter, simply referred to as a printer) that records on a recording medium using ink (liquid) will be described as an example. In the drawings used in the following description, the scale of each member is appropriately changed in order to make each member recognizable.

(First Embodiment)
[Printer]
FIG. 1 is a schematic configuration diagram of a printer 1.
As shown in FIG. 1, the printer 1 of the present embodiment includes a pair of transport mechanisms 2 and 3, an ink supply mechanism 4, inkjet heads 5A and 5B, and a scanning mechanism 6. In the following description, the X, Y, and Z orthogonal coordinate systems will be used as necessary. In this case, the X direction coincides with the transport direction (sub-scanning direction) of the recording medium P (for example, paper or the like). The Y direction (normal direction) coincides with the scanning direction (main scanning direction) of the scanning mechanism 6. The Z direction indicates a height direction orthogonal to the X direction and the Y direction. In the following description, of the X direction, the Y direction, and the Z direction, the arrow direction in the figure is defined as a plus (+) direction, and the direction opposite to the arrow is defined as a minus (−) direction.

The transport mechanisms 2 and 3 transport the recorded medium P in the + X direction. Specifically, the transport mechanism 2 includes a grit roller 11 extended in the Y direction, a pinch roller 12 extended in parallel with the grit roller 11, and a drive mechanism such as a motor for axially rotating the grit roller 11 (non-delivery). (Illustrated) and. Similarly, the transport mechanism 3 includes a grit roller 13 extended in the Y direction, a pinch roller 14 extended in parallel with the grit roller 13, and a drive mechanism (not shown) for axially rotating the grit roller 13. It is equipped with.

The ink supply mechanism 4 includes an ink tank 15 containing ink and an ink pipe 16 connecting the ink tank 15 and the inkjet heads 5A and 5B.
In this embodiment, a plurality of ink tanks 15 are arranged in the X direction. Each ink tank 15 contains inks of four colors, for example, yellow, magenta, cyan, and black, separately.
The ink pipe 16 is, for example, a flexible hose having flexibility. The ink pipe 16 is connected between each ink tank 15 and each of the inkjet heads 5A and 5B.

The scanning mechanism 6 reciprocates the inkjet heads 5A and 5B in the Y direction. Specifically, the scanning mechanism 6 moves the pair of guide rails 21 and 22 extending in the Y direction, the carriage 23 movably supported by the pair of guide rails 21 and 22, and the carriage 23 in the Y direction. It is provided with a drive mechanism 24 for driving.

The drive mechanism 24 is arranged between the guide rails 21 and 22 in the X direction. The drive mechanism 24 is a drive that rotationally drives a pair of pulleys 25 and 26 arranged at intervals in the Y direction, an endless belt 27 wound between the pair of pulleys 25 and 26, and one of the pulleys 25. It includes a motor 28.

The carriage 23 is connected to the endless belt 27. A plurality of inkjet heads 5A and 5B are mounted on the carriage 23 in a state of being arranged in the Y direction. Each inkjet head 5A, 5B is configured to be capable of ejecting two colors of ink for one inkjet head 5A, 5B. Therefore, in the printer 1 of the present embodiment, each of the inkjet heads 5A and 5B is configured to be capable of ejecting four colors of ink, yellow, magenta, cyan, and black, by ejecting inks of two colors different from each other. ..

<Inkjet head>
FIG. 2 is a perspective view of the inkjet head 5A. The inkjet heads 5A and 5B have the same configuration except for the color of the supplied ink. Therefore, in the following description, the inkjet head 5A will be described, and the description of the inkjet head 5B will be omitted.
As shown in FIG. 2, in the inkjet head 5A of the present embodiment, the head modules 30A to 30D, the damper 31, the nozzle plate (injection hole plate) 32, the nozzle guard (injection hole guard) 33, and the like are mounted on the base member 38. It is composed of. In FIG. 2, the cover and the like covering the head modules 30A to 30D and the damper 31 and the like are not shown.

(Base member)
FIG. 3 is a perspective view showing a state in which a part of the inkjet head 5A is removed.
As shown in FIG. 3, the base member 38 is formed in a plate shape with the Z direction as the thickness direction and the X direction as the longitudinal direction. The base member 38 has a module holding portion 41 for holding the head modules 30A to 30D, and a carriage fixing portion 42 for fixing the base member 38 to the carriage 23 (see FIG. 1). In this embodiment, the base member 38 is integrally formed of a metal material.

The module holding portion 41 is formed in a frame shape in a plan view seen from the Z direction. That is, a mounting opening 44 that penetrates the base member 38 in the Z direction is formed in the central portion of the module holding portion 41 in the XY plane. Insertion grooves 46 are formed in each of the pair of short side portions 45 located on both sides of the module holding portion 41 in the X direction. The insertion grooves 46 of the present embodiment are a plurality of insertion grooves 46 formed on each short side portion 45, with the insertion grooves 46 facing each other in the X direction as one set and spaced apart in the Y direction. (For example, four sets) are formed.

Each insertion groove 46 is recessed in the X direction with respect to the inner peripheral surface of the short side portion 45, and penetrates the short side portion 45 in the Z direction. That is, the insertion groove 46 communicates with the mounting opening 44. The head modules 30A to 30D can be inserted into the insertion grooves 46 of each set facing each other in the X direction. Of the insertion grooves 46 of each set, on the inner surface of one of the insertion grooves 46, a first urging member (a first urging member that urges the head modules 30A to 30D toward the other insertion groove 46 in one direction in the X direction). (Not shown) is arranged. In the present embodiment, the first urging member is formed in a leaf spring shape.

The carriage fixing portion 42 projects from the + Z direction end portion of the module holding portion 41 in the XY plane. The carriage fixing portion 42 is formed with mounting holes and the like for mounting the base member 38 to the carriage 23 (see FIG. 1).

(Head module)
As shown in FIG. 2, the head modules 30A to 30D are configured so that the ink supplied from the ink tank 15 (see FIG. 1) can be ejected toward the recording medium P. A plurality of head modules 30A to 30D are mounted on the base member 38 at intervals in the Y direction. In this embodiment, four head modules, a first head module 30A, a second head module 30B, a third head module 30C, and a fourth head module 30D, are mounted on the base member 38.

In the inkjet head 5A of the present embodiment, two head modules out of the four head modules 30A to 30D eject ink of one color. Specifically, the first head module 30A and the second head module 30B are configured to be capable of ejecting ink of the same color, and the third head module 30C and the fourth head module 30D are configured to be capable of ejecting ink of the same color. The number of head modules 30A to 30D mounted on the base member 38, the type of ink ejected from the head modules 30A to 30D, and the like can be appropriately changed. Further, since each of the head modules 30A to 30D has a corresponding configuration, the first head module 30A will be described as an example in the following description.

FIG. 4 is a perspective view of the first head module 30A.
As shown in FIG. 4, the first head module 30A mainly includes a head tip 51, a manifold 52, and a drive board (heating mechanism) 53.

(Head tip)
FIG. 5 is an exploded perspective view of the head tip 51.
As shown in FIG. 5, the head tip 51 is a so-called edge shoot type that ejects ink from an end portion in the extending direction (Z direction) in the ejection channel 57, which will be described later. Specifically, the head tip 51 is configured by superimposing the actuator plate 55 and the cover plate 56 in the Y direction.

The actuator plate 55 is a so-called monopole substrate in which the polarization direction is set in one direction along the thickness direction (Y direction). As the actuator plate 55, for example, a ceramic substrate made of PZT (lead zirconate titanate) or the like is preferably used. Further, the actuator plate 55 may be formed by laminating two piezoelectric substrates having different polarization directions in the Y direction (so-called chevron type).

A plurality of channels 57 and 58 are arranged side by side at intervals in the X direction on the surface of the actuator plate 55 facing the + Y direction (hereinafter referred to as “surface”). Each of the channels 57 and 58 is formed linearly along the Z direction. Each channel 57, 58 opens on the −Z direction end face of the actuator plate 55 and terminates at the + Z direction end of the actuator plate 55. It should be noted that the channels 57 and 58 may extend at an angle with respect to the Z direction.

The plurality of channels 57 and 58 described above are the ejection channel 57 filled with ink and the non-ejection channel 58 not filled with ink. The discharge channel 57 and the non-discharge channel 58 are arranged side by side alternately in the X direction. Each of the channels 57 and 58 is partitioned in the X direction by a drive wall 61 made of an actuator plate 55. A drive electrode (not shown) is formed on the inner surfaces of the channels 57 and 58.

The cover plate 56 is formed in a rectangular shape when viewed from the front in the Y direction. The cover plate 56 is joined to the surface of the actuator plate 55 with the + Z direction end of the actuator plate 55 protruding.

The cover plate 56 has a common ink chamber 62 formed on a surface facing the + Y direction (hereinafter referred to as “front surface”) and a plurality of slits 63 formed on a surface facing the −Y direction (hereinafter referred to as “back surface”). And have.
The common ink chamber 62 is formed at a position equivalent to the + Z direction end portion of the ejection channel 57 in the Z direction. The common ink chamber 62 is recessed from the surface of the cover plate 56 in the −Y direction and extends in the X direction. Ink flows into the common ink chamber 62 through the manifold 52 described above.
The slit 63 is formed in the common ink chamber 62 at a position facing the ejection channel 57 in the Y direction. The slit 63 communicates the inside of the common ink chamber 62 and the inside of each ejection channel 57 separately. On the other hand, the non-ejection channel 58 does not communicate with the common ink chamber 62.

As shown in FIG. 4, the heat transfer plate 65 is attached to the surface of the actuator plate 55 described above facing the −Y direction (hereinafter referred to as “back surface”). The heat transfer plate 65 is made of a material having excellent thermal conductivity (for example, aluminum or the like). The heat transfer plate 65 is provided on the back surface of the actuator plate 55 so as to cover the entire area of each of the channels 57 and 58. The size and position of the heat transfer plate 65 can be changed as appropriate.

(Manifold)
As shown in FIG. 3, the manifold 52 has an ink flow path 71 (see FIG. 6) through which ink flows toward the head chip 51 described above. The manifold 52 is formed in a plate shape with the Y direction as the thickness direction as a whole. The manifold 52 is inserted into a set of insertion grooves 46 facing each other in the X direction among the above-mentioned insertion grooves 46, and is held by the base member 38 in an upright state in the + Z direction. As shown in FIG. 4, at the end portions of the manifold 52 in the −Z direction, second urging members 70 are provided at both ends in the X direction. The second urging member 70 is interposed between the inner surface of the insertion groove 46 and the manifold 52 in the insertion groove 46 to urge the first head module 30A in the −Y direction. In the present embodiment, the second urging member 70 is formed in a leaf spring shape.

FIG. 6 is an exploded perspective view of the manifold 52.
As shown in FIG. 6, the manifold 52 has a flow path member 7272 and a flow path cover 73 superposed on the flow path member 72 in the Y direction.
The flow path member 72 is integrally formed of a material having excellent thermal conductivity. In the present embodiment, a metal material (for example, aluminum or the like) is preferably used as the material of the flow path member 72.

The flow path member 72 includes a flow path plate 75 and an inflow port 76.
The flow path plate 75 is formed in a rectangular plate shape with the Y direction as the thickness direction. An ink flow path 71 is formed on the surface of the flow path plate 75 facing the −Y direction. The ink flow path 71 is formed in a groove shape that is recessed in the + Y direction. Specifically, the ink flow path 71 has a meandering portion 79 and a communication portion 80.

The meandering portion 79 extends in the Z direction while meandering in the X direction. The + Z direction end of the meandering portion 79 communicates with the inflow port 76. On the other hand, the end portion in the −Z direction of the meandering portion 79 communicates with the communication portion 80 at the central portion in the X direction of the flow path plate 75. The meandering direction of the meandering portion 79 is long with respect to the straight line connecting the communicating portion between the meandering portion 79 and the inflow port 76 and the communicating portion between the meandering portion 79 and the communicating portion 80. If so, it can be changed as appropriate. For example, the meandering portion 79 may be configured to meander in the Z direction and extend in the X direction.
The communication portion 80 extends in the X direction at the end portion of the flow path plate 75 in the −Z direction. The communication portion 80 has the same shape as the above-mentioned common ink chamber 62 when viewed from the front in the Y direction.

In the first head module 30A, the inflow port 76 is provided at the end of the flow path plate 75 in the + Z direction at the end in the −X direction. The inflow port 76 is formed in a cylindrical shape protruding from the flow path plate 75 in the + Z direction. The −Z direction end of the inflow port 76 communicates with the meandering portion 79 described above. It is preferable that a film having corrosion resistance (ink resistance) is formed on at least a portion of the manifold 52 that is in contact with ink (inner surface of the ink flow path 71 or inner surface of the inflow port 76). When a solvent-based ink is used as the film, for example, a surface treatment such as nickel plating or anodizing can be preferably selected. The coating may be applied to the entire surface of the manifold 52.

The flow path cover 73 has an outer shape equivalent to that of the flow path plate 75 when viewed from the front in the Y direction, and is formed in a rectangular plate shape having a thickness in the Y direction thinner than that of the flow path plate 75. The flow path cover 73 is fixed to the surface of the flow path plate 75 facing the −Y direction, and closes the ink flow path 71 described above from the −Y direction. A communication hole 82 for opening the communication portion 80 is formed at a position of the flow path cover 73 that overlaps with the communication portion 80 when viewed from the Y direction. The communication hole 82 has the same shape as the communication portion 80 when viewed from the Y direction.

In this embodiment, the flow path cover 73 is made of a metal material (for example, stainless steel) having excellent thermal conductivity. Further, in the present embodiment, the case where the groove-shaped ink flow path 71 is formed only in the flow path member 72 has been described, but the present invention is not limited to this configuration, and at least one of the flow path member 72 and the flow path cover 73 is not limited to this configuration. It does not matter if an ink flow path is formed in the ink flow path. In this case, for example, a groove may be formed in each of the flow path member 72 and the flow path cover 73, and the groove portions of the flow path member 72 and the flow path cover 73 may be overlapped to form an ink flow path.

An insulating sheet 86 is provided on the surface of the flow path cover 73 facing the −Y direction. The insulating sheet 86 is formed in a frame shape when viewed from the front in the Y direction. The insulating sheet 86 surrounds the communication hole 82 on the surface of the flow path cover 73 facing the −Y direction. The insulating sheet 86 is fixed to the surface of the flow path cover 73 facing the −Y direction by adhesion or the like. In the present embodiment, for example, polyimide is preferably used as the insulating sheet 86. However, the material of the insulating sheet 86 has characteristics that can sufficiently reduce the stray capacitance (a material having a low dielectric constant, a material that can reduce the dielectric constant in a short space distance, etc.) and ink resistance (resistance to ink). It can be appropriately changed as long as it is made of a material (for example, a resin material or a rubber material) that has (elution property) and is relatively soft (with a small Young's modulus).

Here, as shown in FIGS. 4 and 6, the above-mentioned head tip 51 is on a surface (first surface facing the third direction) of the flow path cover 73 facing the −Y direction with the insulating sheet 86 interposed therebetween. It is fixed to. Specifically, the head tip 51 is fixed to the insulating sheet 86 by adhesion or the like with the surface of the cover plate 56 (the surface facing the manifold 52) facing the insulating sheet 86. At this time, the common ink chamber 62 of the cover plate 56 communicates with the communication portion 80 through the communication hole 82. As a result, the ink circulating in the ink flow path 71 is supplied to the head chip 51. The head tip 51 projects in the −Z direction with respect to the manifold 52 in a state of being fixed to the manifold 52. Further, in the example shown in FIG. 4, the length of the head tip 51 in the X direction is shorter than the length of the manifold 52 in the X direction.

As shown in FIG. 2, the heater (heating mechanism) 85 is arranged on the surface of the flow path member 72 (flow path plate 75) facing the + Y direction (the second surface facing the third direction). The heater 85 heats the inside of the ink flow path 71 through the flow path member 72 to keep the ink flowing in the ink flow path 71 within a predetermined temperature range (heat retention).

As shown in FIG. 4, the drive board 53 is a so-called flexible printed circuit board, and is configured by mounting a wiring pattern and various electronic components on a base film. The drive board 53 has a module control unit 88 supported by the manifold 52, and a chip connection unit 89 for connecting the module control unit 88 and the head chip 51. As for the drive board 53, a rigid board or the like may be used for the module control unit 88 as long as the chip connection portion 89 is composed of at least a flexible board.

The module control unit 88 is formed in a rectangular shape when viewed from the front in the Y direction. Electronic components such as a driver IC are mounted on the module control unit 88. The module control unit 88 is fixed to the manifold 52 with a support plate 90 sandwiched between portions located in the + Z direction with respect to the head tip 51 on the surface of the flow path cover 73 facing the −Y direction. The support plate 90 is made of a material having excellent thermal conductivity (for example, a metal material). The support plate 90 may not be provided. That is, the module control unit 88 may be directly fixed to the manifold 52.

As shown in FIG. 2, the drive board 53 is electrically connected to the external connection board 92 via a drawer unit 91 drawn out from the module control unit 88 in the + Z direction. The external connection board 92 relays control signals and drive voltages to the head modules 30A to 30D (driver ICs) output from the main control board (not shown) mounted on the printer 1. Then, the drive board 53 drives the head chip 51 based on the control signal and the drive voltage relayed by the external connection board 92.

As shown in FIG. 4, the chip connecting portion 89 extends in the −Z direction from the module control unit 88 with a gap in the Y direction with respect to the flow path cover 73. The −Z direction end portion of the chip connection portion 89 is fixed to the + Z direction end portion of the actuator plate 55 described above by crimping or the like. As a result, the drive substrate 53 and the drive electrodes of the head chip 51 are electrically connected.

The drive board 53 includes a sensor connection unit 93 pulled out from the + X direction end portion of the module control unit 88. The sensor connection portion 93 is extended to a position where it overlaps with the heat transfer plate 65 described above when viewed from the Y direction. A temperature sensor 94 (for example, a thermistor or the like) for detecting the ink temperature in the ejection channel 57 is mounted on the tip of the sensor connection portion 93. The temperature sensor 94 is arranged on the back surface of the actuator plate 55 with a heat transfer plate 65 interposed therebetween.

As shown in FIG. 3, the first head module 30A is inserted into the mounting opening 44 with the manifold 52 inserted into the insertion groove 46 as described above. At this time, in the first head module 30A, the head tip 51 faces in the −Y direction, and the −Z direction end surface of the head chip 51 is flush with the −Z direction end surface of the base member 38 (module holding portion 41). It is held by the base member 38.

As shown in FIGS. 2 and 3, the second head module 30B is inserted into the insertion groove 46 adjacent to the insertion groove 46 into which the manifold 52 of the first head module 30A is inserted in the −Y direction. In this state, it is inserted into the mounting opening 44. At this time, the second head module 30B is held by the base member 38 with the head tip 51 facing the head tip 51 of the first head module 30A in the Y direction. Further, the inflow ports 76 of the first head module 30A and the second head module 30B are arranged at the same positions in the X direction.

The head chips 51 of the second head module 30B are arranged (staggered) with the arrangement pitch of the discharge channels 57 deviating by half a pitch from the head chips 51 of the first head module 30A. As a result, the head chips 51 of the first head module 30A and the second head module 30B cooperate to eject one color of ink, so that characters and images recorded on the recording medium P can be recorded at high density. It has become. In the first head module 30A and the second head module 30B, the arrangement pitch of the discharge channels 57 of the head tip 51 can be appropriately changed.

Further, as shown in FIG. 2, the third head module 30C and the fourth head module 30D are the same as the first head module 30A and the second head module 30B described above with the head chips 51 facing each other. It is held by the base member 38 by the method. Each head module 30A to 30D is fixed to the base member 38 via a stay (not shown) erected in the + Z direction from the base member 38. The inflow port 76 of the third head module 30C and the fourth head module 30D is on the opposite side of the inflow port 76 of the first head module 30A and the second head module 30B in the X direction (+ X direction in the flow path plate 75). Is located at the end of the module).

(damper)
The damper 31 is provided in the + Z direction with respect to the head modules 30A to 30D, corresponding to the color of the ink. That is, one damper 31 of the present embodiment is provided for each of the two head modules (for example, the head modules 30A and 30B). The dampers 31 are provided side by side in the Y direction. Each damper 31 has the same configuration except for the color of the supplied ink. Therefore, in the following description, one damper 31 (damper for head modules 30A and 30B) will be described, and the description of the other damper 31 will be omitted.

The damper 31 is attached to the head modules 30A and 30B in the + Z direction via a stay (not shown) fixed to the base member 38. The damper 31 has an inlet port 100, a pressure buffer 101, and an outlet port 102. The damper 31 may be provided separately from the inkjet head 5A.

The inlet port 100 is formed in a cylindrical shape protruding from the pressure buffer portion 101 in the + Z direction. The ink pipe 16 (see FIG. 1) described above is connected to the inlet port 100. Ink in the ink tank 15 flows into the inlet port 100 through the ink pipe 16.
The pressure buffer portion 101 is formed in a box shape. The pressure buffer portion 101 is configured such that a movable membrane or the like is housed inside the pressure buffer portion 101. The pressure buffer 101 is arranged between the ink tank 15 (FIG. 1) and the head modules 30A and 30B, and absorbs the pressure fluctuation of the ink supplied to the damper 31 through the inlet port 100.
The outlet port 102 is formed in a cylindrical shape protruding from the pressure buffer portion 101 in the −X direction. The ink discharged from the pressure buffer 101 flows into the outlet port 102.

A filter unit 110 is connected to the outlet port 102. The filter unit 110 contains a filter (not shown) inside. The filter unit 110 removes air bubbles, foreign substances, and the like contained in the ink discharged from the damper 31 by a filter. The filter unit 110 has branch portions 111 and 112 for bifurcating the ink discharged from the damper 31. One branch portion 111 is connected to the inflow port 76 of the first head module 30A via the connection tube 113. The other branch portion 112 is connected to the inflow port 76 of the second head module 30B via the connection tube 114. The filter unit 110 is fixed to the base member 38 via a stay (not shown). Further, the above-mentioned external connection board 92 is arranged between the dampers 31 facing each other in the Y direction.

FIG. 7 is an exploded perspective view of the base member 38, the nozzle plate 32, and the nozzle guard 33.
As shown in FIG. 7, of the above-mentioned base member 38, the spacer 120 is fixed to the −Z direction end surface (plate arrangement surface) of the module holding portion 41. The spacer 120 is made of polyimide, SUS, or the like. The spacer 120 is adhered to the end face of the module holding portion 41 in the −Z direction using a soft adhesive. As the soft adhesive, a silicone-based adhesive (for example, manufactured by ThreeBond Co., Ltd.: 1211) or the like is preferably used.

The spacer 120 covers the end face of the module holding portion 41 in the −Z direction from the −Z direction. A spacer opening 121 that exposes the head tip 51 in the −Z direction is formed at a position of the spacer 120 that overlaps the head tip 51 of each of the head modules 30A to 30D when viewed from the Z direction. In the present embodiment, the spacer opening 121 exposes the head tip 51 for each color (for example, the head tip 51 of the first head module 30A and the second head module 30B) together. The spacer opening 121 may expose the head tips 51 of the head modules 30A to 30D together, or may expose the head tips 51, respectively.

(Nozzle plate)
The nozzle plate 32 described above is made of a resin material such as polyimide. The + Z direction end surface (opposing surface to the base member 38) of the nozzle plate 32 is fixed to the above-mentioned spacer 120 and the −Z direction end surface of the head tip 51 with a hard adhesive. The hard adhesive is made of a material that is harder, for example, with a shore hardness as compared with the above-mentioned soft adhesive. As such a material, an epoxy adhesive (for example, manufactured by Able Stick Co., Ltd .: 931-1T1N1) or the like is preferably used. The nozzle plate 32 may be directly adhered to the base member 38 using a soft adhesive.

As shown in FIGS. 2 and 7, the nozzle plate 32 collectively covers the head tips 51 of the head modules 30A to 30D from the −Z direction. A plurality of nozzle rows (first nozzle row 130A to fourth nozzle row 130D) extending in the X direction are formed on the nozzle plate 32 at intervals in the Y direction.
Each nozzle row (injection hole row) 130A to 130D is formed at a position of the nozzle plate 32 facing the head tip 51 of the corresponding head modules 30A to 30D in the Z direction.

FIG. 8 is a partial bottom view of the inkjet head 5A as viewed from the −Z direction.
As shown in FIG. 8, each nozzle row 130A to 130D has a nozzle hole (first nozzle hole 131A to fourth nozzle hole 131D) penetrating the nozzle plate 32 in the Z direction. For example, the first nozzle hole (injection hole) 131A is formed separately in the nozzle plate 32 at a position facing the discharge channel 57 of the head tip 51 in the first head module 30A in the Z direction. That is, the plurality of first nozzle holes 131A are formed linearly with an interval in the X direction to form the first nozzle row 130A.
The second nozzle hole 131B, the third nozzle hole 131C, and the fourth nozzle hole 131D are the head tips 51 of the corresponding head modules 30B to 30D among the nozzle plates 32, similarly to the first nozzle hole 131A described above. Each is separately formed at a position facing the discharge channel 57 in the Z direction.

As shown in FIG. 7, a slit 135 that penetrates the nozzle plate 32 in the Z direction is formed in a portion of the nozzle plate 32 located between the second nozzle row 130B and the third nozzle row 130C in the Y direction. Has been done. In the present embodiment, the slits 135 are formed in two rows with an interval in the Y direction. The slit 135 extends parallel to the nozzle rows 130A to 130D along the X direction. Further, the length of the slit 135 in the X direction is longer than that of the nozzle rows 130A to 130D. However, the length of the slit 135 can be appropriately changed as long as it is shorter than the length of the nozzle plate 32 in the X direction. Further, the number of slits 135 is not limited to two rows and can be changed as appropriate.

The nozzle plate 32 is not limited to the resin material, but may be formed of a metal material (stainless steel or the like), or may have a laminated structure of the resin material and the metal material. However, the nozzle plate 32 is preferably a material having a coefficient of thermal expansion equivalent to that of the spacer 120. Further, the end face of the nozzle plate 32 in the −Z direction is treated with a liquid repellent treatment. In the present embodiment, a configuration in which one nozzle plate 32 covers each head module 30A to 30D together has been described, but the present invention is not limited to this configuration, and each head module 30A to 30D is individually covered by a plurality of nozzle plates 32. It may be configured to cover with. The nozzle plate 32 may not be treated with a liquid repellent treatment.

(Nozzle guard)
The nozzle guard 33 is formed by pressing a plate material such as stainless steel. The nozzle guard 33 covers the module holding portion 41 from the −Z direction with the nozzle plate 32 and the spacer 120 sandwiched between them.

An exposed hole 141 is formed in the nozzle guard 33 at a position facing the nozzle rows 130A to 130D described above in the Z direction to expose the nozzle rows 130A to 130D to the outside. The exposed hole 141 penetrates the nozzle guard 33 in the Z direction and is formed in a slit shape extending in the X direction. The exposed holes 141 of the present embodiment are formed in two rows with an interval in the Y direction corresponding to the nozzle rows 130A to 130D for ejecting ink of the same color. That is, one of the exposed holes 141 exposes the first nozzle row 130A and the second nozzle row 130B to the outside. Further, the other exposed hole 141 exposes the third nozzle row 130C and the fourth nozzle row 130D to the outside.

As shown in FIG. 8, the nozzle guard 33 is fixed to the spacer 120 described above by adhesion or the like. Specifically, the nozzle guard 33 is adhered to a portion of the spacer 120 located outside the nozzle plate 32 in a plan view from the Z direction (hereinafter, referred to as “first adhesive region 150”). The first adhesive region 150 is set in a frame shape that surrounds the periphery of the nozzle plate 32 over the entire circumference. The first adhesive region 150 may be adhered to the outer peripheral edge of the nozzle plate 32 as long as it is adhered to the spacer 120 at least outside the nozzle plate 32.

Further, the nozzle guard 33 is adhered to the portion of the spacer 120 exposed through the slit 135 described above of the nozzle plate 32 (hereinafter referred to as “second adhesive region 151”). That is, the second adhesive region 151 extends in parallel with the nozzle rows 130A to 130D along the X direction. As a result, the second bonding region 151 partitions between the nozzle rows of different colors (between the second nozzle row 130B and the third nozzle row 130C) among the nozzle rows 130A to 130D.

[How the printer works]
Next, a method of recording information on the recording medium P by using the above-mentioned printer 1 will be described.
As shown in FIG. 1, when the printer 1 is operated, the grit rollers 11 and 13 of the transport mechanisms 2 and 3 rotate, so that the recorded medium P is placed between the grit rollers 11 and 13 and the pinch rollers 12 and 14. It is conveyed in the + X direction. At the same time, the drive motor 28 rotates the pulley 26 to drive the endless belt 27. As a result, the carriage 23 reciprocates in the Y direction while being guided by the guide rails 21 and 22.
During this period, a drive voltage is applied to the drive electrodes of the head chip 51 in each of the inkjet heads 5A and 5B. As a result, the drive wall 61 is deformed by a thickness slip, and a pressure wave is generated in the ink filled in the ejection channel 57. Due to this pressure wave, the internal pressure of the ejection channel 57 increases, and the ink is ejected through the nozzle holes 131A to 131D. Then, when the ink lands on the recording medium P, various information is recorded on the recording medium P.

Here, in the present embodiment, for example, in the first head module 30A, the head chip 51 and the drive substrate 53 are supported by the manifold 52 having the ink flow path 71.
According to this configuration, the member supporting the head chip 51 and the drive substrate 53 and the ink flow path 71 are integrated in the manifold 52 arranged on one side in the Y direction with respect to the head chip 51. As a result, as in the conventional case, a member that supports the head chip and the drive board is arranged on one side in the Y direction with respect to the head chip, and a member having an ink flow path on the other side in the Y direction is separately arranged with respect to the head chip. It is possible to reduce the size of the first head module 30A in the Y direction (main scanning direction) as compared with the configuration. This makes it possible to reduce the size of the inkjet head 5A in the Y direction.
Further, the heat generated in the head chip 51 and the drive board 53 is dissipated to the outside via the manifold 52. As a result, the heat dissipation performance of the head chip 51 and the drive board 53 can be ensured.
Further, since the head tip 51 and the drive board 53 are supported by the manifold 52 having the ink flow path 71, the ink flow path is generated by using the exhaust heat generated in the head chip 51 and the drive board 53 and transmitted to the manifold 52. It is also possible to heat (keep warm) the ink flowing through the 71. As a result, the ink can be supplied to the head chip 51 at a desired temperature (viscosity), and excellent printing characteristics can be obtained.
Moreover, in the present embodiment, since the head modules 30A to 30D can be miniaturized in the Y direction, a manifold 52 can be provided for each head chip 51. Therefore, in order to achieve high-density recording, the heat dissipation performance of each head chip 51 can be ensured as compared with the configuration in which a plurality of head chips 51 are mounted on one head module 30A to 30D.

In the present embodiment, since the damper 31 is arranged in the + Z direction with respect to the manifold 52, the size of the inkjet head 5A in the Y direction is reduced as compared with the configuration in which the damper 31 and the manifold 52 are provided side by side in the Y direction. Can be planned.

In the present embodiment, since the ink flow path 71 meanders and extends, the ink flow path is between the communication portion between the meandering portion 79 and the inflow port 76 and the communication portion between the meandering portion 79 and the communication portion 80. The heat transfer area between the ink and the manifold 52 can be increased as compared with the case where the ink is formed linearly. Therefore, the exhaust heat of the head chip 51 and the drive substrate 53 and the heat of the heater 85 can be effectively transferred to the ink in the ink flow path 71. As a result, the ink can be supplied to the head tip 51 at a desired temperature (viscosity), so that the temperature of the ink at the time of ejection can be maintained within a desired range. As a result, it is possible to suppress variations in the amount of ink ejected and the ejection speed, and to obtain excellent printing characteristics.

In the present embodiment, the heater 85 is arranged on the surface of the manifold 52 facing the + Y direction (the surface opposite to the surface supporting the drive substrate 53).
According to this configuration, the ink circulating in the ink flow path 71 can be heated by the heater 85 in addition to the exhaust heat of the head chip 51 and the drive substrate 53, so that the ink can be reliably transferred to the head chip 51 at a desired temperature. Can be supplied.

In the present embodiment, since the drive substrate 53 is supported by the manifold 52, the ink can be heated by utilizing the waste heat of the drive substrate 53 as described above. As a result, the power consumption required for heating the ink can be reduced as compared with the case where the ink is heated only by the heater 85.
Further, since the heat generated in the drive board 53 is effectively dissipated to the ink flowing through the manifold 52 and the ink flow path 71, it is possible to suppress the temperature of the drive board 53 from becoming high.

In the present embodiment, since a coating having corrosion resistance is formed on the inner surface of the ink flow path 71 or the like, corrosion of the manifold 52 due to ink can be suppressed and durability can be improved.

In the present embodiment, since the insulating sheet 86 is interposed between the head tip 51 and the manifold 52, the stray capacitance between the head tip 51 and the manifold 52 can be reduced. As a result, the electrical noise generated when the head chip 51 is driven can be suppressed, and the operation reliability of the inkjet head 5A can be ensured.
Further, by using a material having ink resistance such as polyimide for the insulating sheet 86, it is possible to suppress the insulating sheet 86 from being eluted by the ink and suppress the ejection failure.
Further, by using a soft material such as polyimide for the insulating sheet 86, the stress acting on the head tip 51 and the manifold 52 due to the difference in the coefficient of thermal expansion between the head tip 51 and the manifold 52 can be relaxed. As a result, for example, cracking of the head tip 51 and peeling of the head tip 51 from the manifold 52 can be suppressed.

In the present embodiment, the nozzle plate 32 having the nozzle rows 130A to 130D corresponding to the head modules 30A to 30D is arranged on the end face in the −Z direction of the base member 38.
According to this configuration, the positional accuracy of the nozzle holes 131A to 131D can be improved as compared with the configuration in which the nozzle plate 32 is attached to each of the head modules 30A to 30D.

In the present embodiment, since the spacer 120 is interposed between the nozzle plate 32 and the base member 38, the nozzle plate 32 and the base member 38 are caused by the difference in the coefficient of thermal expansion between the nozzle plate 32 and the base member 38. The stress acting on and can be relaxed.
Further, in the present embodiment, since the spacer 120 is adhered to the base member 38 with a soft adhesive, it acts on the spacer 120 and the base member 38 due to the difference in the coefficient of thermal expansion between the spacer 120 and the base member 38. The stress to be applied can be surely relieved.
As a result, it is possible to prevent the nozzle plate 32 from peeling off from the head tip 51.

In the present embodiment, the first adhesive region 150 between the nozzle guard 33 and the spacer 120 is arranged so as to surround the periphery of the nozzle plate 32.
According to this configuration, when the ink adhering to the end face of the nozzle plate 32 or the nozzle guard 33 in the −Z direction tries to enter the inkjet head 5A through the gap between the nozzle plate 32 and the nozzle guard 33, The ink can be blocked by one adhesive region 150. As a result, it is possible to prevent the ink from entering the inside of the inkjet head 5A.

In the present embodiment, the second adhesive region 151 between the nozzle guard 33 and the spacer 120 is arranged between the nozzle rows 130B and 130C in which different color inks are ejected from the nozzle rows 130A to 130D. did.
According to this configuration, the different color ink adhering to the end surface in the −Z direction of the nozzle plate 32 and the like is blocked by the second adhesive region 151. As a result, it is possible to prevent inks of different colors from being mixed and leaking to the outside of the inkjet head 5A.

In the present embodiment, the first urging member and the second urging member that urge the base member 38 and the head modules 30A to 30D in either the X direction or the Y direction between the base member 38 and the head modules 30A to 30D. The configuration is such that the force member 70 intervenes.
According to this configuration, the head modules 30A to 30D are held by the base member 38 in a state of being pressed in either the X direction or the Y direction. Therefore, the head modules 30A to 30D can be positioned with high accuracy with respect to the base member 38. This makes it possible to improve the assembling property when the head modules 30A to 30D are subsequently fixed to the base member 38 via a stay or the like.

In the present embodiment, since the temperature sensor 94 is arranged on the back surface of the actuator plate 55, the ink temperature of the ejection channel 57 can be detected more accurately than when the temperature sensor 94 is arranged at a position away from the actuator plate 55. ..
In particular, in the present embodiment, a heat transfer plate 65 is provided between the temperature sensor 94 and the actuator plate 55 so as to cover the entire area of each of the channels 57 and 58. Therefore, the average ink temperature in all the ejection channels 57 can be detected.

Since the printer 1 of the present embodiment includes the above-mentioned inkjet head 5A, it is possible to provide the printer 1 having excellent reliability while reducing the size in the Y direction.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. FIG. 9 is a front view of the flow path member 200 according to the second embodiment. This embodiment is different from the above-described embodiment in that an ink reservoir 202 for temporarily retaining ink is formed in the ink flow path 201. In the following description, the same reference numerals are given to the configurations different from those of the first embodiment described above, and the description thereof will be omitted.
In the flow path member 200 of the manifold 210 shown in FIG. 9, the ink flow path 201 has a portion located upstream of the communication portion 80 meandering and extending. Specifically, the ink flow path 201 includes an ink sump 202, an upstream main flow path 203 connected to the upstream side of the ink sump 202, and a downstream main flow path connected to the downstream side of the ink sump 202. It is equipped with 204.

The ink sump 202 is formed in the central portion (the central portion in the X direction and the Z direction) of the surface of the flow path member 200 facing the −Y direction. The ink sump 202 is formed in a parallel quadrilateral shape extending in an inclined direction in the + Z direction toward the + X direction when viewed from the front in the Y direction. The volume of the ink reservoir 202 is larger than that of the upstream main flow path 203 and the downstream main flow path 204. In addition, fins or the like may be formed on the inner surface of the ink sump 202.

The upstream main flow path 203 is located in the −X direction with respect to the ink reservoir 202 in the flow path member 200. The upstream main flow path 203 extends in the + Z direction from the end face of the flow path member 200 in the + Z direction, and then is folded back (meandering) in the + Z direction. The downstream end of the upstream main flow path 203 is connected to the −X direction end of the ink reservoir 202 from the −Z direction.

The downstream main flow path 204 is located in the + X direction with respect to the ink reservoir 202 in the flow path member 200. The downstream main flow path 204 extends in the −Z direction and then bends (meanders) in the −X direction. The upstream end of the downstream main flow path 204 is connected to the + Z direction end of the ink reservoir 202 from the + X direction. That is, the upstream end of the downstream main flow path 204 is connected to the ink reservoir 202 at a diagonal position with respect to the connection portion between the upstream main flow path 203 and the ink reservoir 202. The downstream end of the downstream main flow path 204 is connected to the communication portion 80 described above. A flow path cover 73 (see FIG. 6) is fixed to the surface of the flow path member 200 facing the −Y direction, for example, as in the above-described embodiment. As a result, the ink flow path 201 is blocked.

In the present embodiment, the ink flowing into the upstream main flow path 203 flows in the upstream main flow path 203 in the −Z direction, and then is folded back in the + Z direction and flows into the ink pool 202. The ink that has flowed into the ink sump 202 once stays in the ink sump 202 and then flows into the downstream main flow path 204 from the + Z direction end of the ink sump 202. The ink that has flowed into the downstream main flow path 204 flows into the communication portion 80 at the downstream end. After that, the ink flowing into the communication unit 80 is supplied to the head chip 51 in the same manner as in the above-described embodiment.

In the present embodiment, the ink flowing through the ink flow path 201 is temporarily stored in the ink pool 202, so that the ink heating time can be secured. As a result, the ink can be supplied to the head tip 51 at a desired temperature (viscosity), so that the temperature of the ink at the time of ejection can be maintained within a desired range. As a result, it is possible to suppress variations in the amount of ink ejected and the ejection speed, and to obtain excellent printing characteristics.

As shown in FIG. 10, a flexible material may be used for the flow path cover 220, and a leaf spring (not shown) that can be elastically deformed in the Y direction may be provided in the ink reservoir 202. According to this configuration, the flow path cover 220 bends and deforms according to the pressure fluctuation in the ink sump 202, so that the pressure fluctuation of the ink supplied to the ink sump 202 can be absorbed. Further, the filter may be arranged in a portion of the ink flow path 201 located near the head chip 51 (for example, the downstream main flow path 204).
In this way, by providing the damper function and the filter function in the manifold 52 (head modules 30A to 30D themselves), it is not necessary to separately provide a damper, a filter, etc., so that further miniaturization and simplification can be achieved. can.

As shown in FIG. 11, the flow path cover may have a flexible inner cover 221 and an outer cover 222 that covers the inner cover 221 from the −Y direction. The outer cover 222 is made of a material (for example, a metal material) having a higher rigidity than the inner cover 221. A bulging portion 222a that bulges in the −Y direction is formed in a portion of the outer cover 222 that covers the ink pool 202. The bulging portion 222a receives the inner cover 221 when the inner cover 221 is bent and deformed in the −Y direction.
In the configuration shown in FIG. 11, since the inner cover 221 can be protected by the outer cover 222, the durability can be improved.

(Third Embodiment)
Next, a third embodiment of the present invention will be described. FIG. 12 is a perspective view of the manifold 300 according to the third embodiment. In the third embodiment, the communication opening 305 penetrating the flow path member 302 is formed in the communication portion of the ink flow path 301 with the head tip 51 (common ink chamber 62), which is the same as the above-described embodiment. It is different. In the following description, the same reference numerals will be given to the same configurations as those in the above-described embodiment, and the description thereof will be omitted.

In the manifold 300 shown in FIG. 12, the flow path member 302 is formed with a communication opening 305 that penetrates the flow path member 302 in the Y direction. The communication opening 305 is formed at a position of the flow path member 302 that overlaps with the common ink chamber 62 when viewed from the front in the Y direction. The communication opening 305 communicates with the common ink chamber 62 through the communication hole 82 (see FIG. 13) of the flow path cover 73 in the −Y direction with respect to the manifold 300.

FIG. 13 is a cross-sectional view corresponding to line XIII-XIII in FIG.
As shown in FIGS. 12 and 13, a film member 308 that closes the communication opening 305 is provided on the surface of the flow path member 302 facing the + Y direction. The film member 308 is made of a flexible material (for example, a resin material or the like). The film member 308 is fixed to the flow path member 302 by adhesion or the like. The inner surface of the communication opening 305 and the portion defined by the film member 308 form a communication portion 310 that communicates with the common ink chamber 62 in the ink flow path 301.

In the present embodiment, since a part of the inner surface of the communication portion 310 is formed by the flexible film member 308, the film member 308 bends and deforms according to the pressure fluctuation in the head tip 51. Thereby, the pressure fluctuation in the head tip 51 can be buffered. For example, the pressure in the ejection channel 57 momentarily decreases due to the decrease in the volume of the ejection channel 57 accompanying the ink ejection. Then, the pressure fluctuation in the discharge channel 57 becomes a pressure wave and propagates in the communication portion 310, and the film member 308 bends and deforms. That is, the film member 308 bends and deforms so as to reduce the volume of the communication portion 310. As a result, the pressure fluctuation generated in the discharge channel 57 can be buffered by the communication unit 310. Further, by buffering the pressure fluctuation by the film member 308, so-called crosstalk (a phenomenon in which the pressure fluctuation in the ejection channel 57 is propagated to another ejection channel 57 through the common ink chamber 62 and the communication opening 305) can be suppressed. As a result, the printing characteristics can be improved.
In particular, in the present embodiment, since the film member 308 is arranged at a position facing the head tip 51 in the Y direction with the flow path member 302 interposed therebetween, the pressure wave propagating from the discharge channel 57 is arranged in the film member 308. Easy to convey to. Therefore, the above-mentioned pressure buffering effect can be effectively exerted.

In the present embodiment, since the communication opening 305 penetrates the flow path member 302 in the Y direction, the manifold 300 is downsized in the Y direction as compared with the case where the communication portion is formed in a groove shape. It becomes easy to secure the volume of the communication portion 310. Then, by securing the volume of the communication portion 310, the pressure fluctuation in the head tip 51 can be easily buffered in the communication portion 310, so that the above-mentioned crosstalk can be suppressed.

In the above-described embodiment, the configuration in which the film member 308 has flexibility has been described, but the configuration is not limited to this configuration. As the film member 308, for example, a metal plate or the like may be adopted. Also in this configuration, by securing the volume of the communication portion 310, the above-mentioned crosstalk can be suppressed.

(Fourth Embodiment)
Next, a fourth embodiment of the present invention will be described. FIG. 14 is a perspective view of the manifold 320 according to the third embodiment. FIG. 15 is a front view of the manifold 320 according to the third embodiment as viewed from the + Y direction. This embodiment differs from the above-described embodiment in that it has a film retainer 321 that presses the film member 308.
In the manifold 320 shown in FIGS. 14 and 15, the film member 308 is made of a flexible material.

A film retainer 321 is arranged on the surface of the film member 308 facing the + Y direction. The film retainer 321 sandwiches the film member 308 with the flow path member 302 in the Y direction. The film retainer 321 is a thin plate formed of a material harder than the film member 308 (for example, a metal material). The film retainer 321 of the present embodiment is formed so that the outer shape of the front view seen from the Y direction is the same as that of the film member 308. The film retainer 321 is fixed to the film member 308 and the flow path member 302 by adhesion or the like.

As shown in FIG. 15, a relief hole 322 that penetrates the film retainer 321 in the Y direction is formed at a position of the film retainer 321 that overlaps with the communication opening 305 when viewed from the Y direction. The relief hole 322 is for preventing interference between the film member 308 and the film retainer 321 when the film member 308 is flexed and deformed. That is, the film member 308 is configured to be able to enter the escape hole 322 when it is flexed and deformed. When viewed from the front in the Y direction, the opening area of the escape hole 322 is preferably equal to or larger than the opening area of the communication opening 305. However, the opening area of the escape hole 322 may be smaller than the opening area of the communication opening 305.

FIG. 16 is a cross-sectional view corresponding to the XVI-XVI line of FIG.
As shown in FIG. 16, of the opening edges of the escape hole 322, a chamfered portion 325 is formed at the opening edge located in the −Y direction. The chamfered portion 325 is, for example, a flat surface. However, the chamfered portion 325 may be a sagging surface or the like formed during round chamfering or processing of the relief hole 322.

In the present embodiment, by sandwiching the film member 308 between the film retainer 321 and the flow path member 302 in the Y direction, peeling of the film member 308 can be suppressed and durability can be improved.
Further, since the chamfered portion 325 is formed at the opening edge located in the −Y direction in the relief hole 322, it is possible to suppress the interference between the film member 308 and the corner portion of the film retainer 321 when the film member 308 is flexed and deformed. .. As a result, damage to the film member 308 can be suppressed and durability can be improved.

For example, as shown in FIG. 17, the accommodating recess 330 accommodating the film member 308 and the film retainer 321 may be formed in the flow path member 302. The accommodating recess 330 is recessed in the −Y direction from the surface of the flow path member 302 facing the + Y direction. The accommodating recess 330 is formed above the outer shape of the film member 308 and the film retainer 321 in the front view, and surrounds the communication opening 305. The amount of the recess in the accommodating recess 330 in the Y direction may be at least a thickness that can accommodate the film member 308 (more than or equal to the thickness of the film member 308). The amount of the recess in the accommodation recess 330 in the Y direction may be, for example, equal to or greater than the total thickness of the film member 308 and the film retainer 321.

According to this configuration, since the accommodating recess 330 is formed in the flow path member 302, the accommodating recess 330 can be used as a guide when the film member 308 or the film retainer 321 is attached to the flow path member 302. This makes it possible to improve the positioning accuracy and the assembly efficiency of the film member 308 and the film retainer 321.
Further, since the amount of protrusion of the film member 308 and the film retainer 321 from the surface of the flow path member 302 facing in the + Y direction can be suppressed, the size of the manifold 320 can be reduced in the Y direction.

The film member 308 and the film retainer 321 may be attached to the flow path member 302 in order. After assembling the film member 308 and the film retainer 321 as a film assembly in advance, the film assembly is attached to the flow path member 302. You may.
By attaching the film member 308 to the flow path member 302 as a film assembly, the handleability can be improved as compared with the case where the film member 308 and the film retainer 321 are attached to the flow path member 302 in order. Unlike the case where the film member 308 and the film retainer 321 are attached to the flow path member 302 in order, it is possible to prevent the adhesive for fixing the film member 308 and the film retainer 321 from entering the escape hole 322. As a result, it is possible to prevent the adhesive from inhibiting the bending deformation of the film member 308.

The technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

For example, in the above-described embodiment, the inkjet printer 1 has been described as an example of the liquid injection device, but the present invention is not limited to the printer. For example, it may be a fax machine, an on-demand printing machine, or the like.

In the above-described embodiment, the configuration in which four head modules 30A to 30D are mounted on the base member 38 has been described, but the configuration is not limited to this configuration. The number of head modules mounted on the base member 38 may be one or a plurality.
In the above-described embodiment, the configuration in which one color ink is ejected by two head modules has been described, but the present invention is not limited to this configuration, and one color ink may be ejected by three or more head modules. One color of ink may be ejected with one head module.

In the above-described embodiment, the head tip of the edge chute has been described, but the present invention is not limited to this. For example, the present invention may be applied to a so-called side shoot type head tip that ejects ink from the central portion of the ejection channel in the extending direction.
Further, the present invention may be applied to a so-called roof chute type head chip in which the direction of pressure applied to ink and the direction of ejection of ink droplets are the same.

In the above-described embodiment, the configuration in which the head tip 51 and the drive substrate 53 are supported on the same surface of the manifold 52 has been described, but the present invention is not limited to this configuration, and the head chip 51 and the heating mechanism (drive substrate 53 and heater 85) are not limited to this configuration. May be supported on different surfaces of the manifold 52.
In the above-described embodiment, the configuration in which both the drive board 53 and the heater 85 are supported by the manifold 52 has been described, but the present invention is not limited to this configuration, and at least one of the drive board 53 and the heater 85 is supported by the manifold 52. It doesn't matter if you have it.

In addition, it is possible to appropriately replace the constituent elements in the above-described embodiments with well-known constituent elements without departing from the spirit of the present invention, and the above-mentioned modifications may be appropriately combined.

(1) An injection hole plate having a plurality of injection hole rows having a plurality of injection holes extending in the first direction arranged side by side in a second direction orthogonal to the first direction, and one of the first directions with respect to the injection hole plate. A head chip having a channel that communicates with the injection hole separately and a third direction that is orthogonal to the first direction and the second direction with respect to the head chip are arranged in one of the third directions. A manifold having a liquid flow path communicating with the channel and being supported by the first surface of the manifold while supporting the head chip on the first surface facing the head chip and electrically connected to the head chip. A liquid injection head characterized by having a drive board.

(2) A damper that is connected to the liquid flow path and absorbs pressure fluctuations of the liquid supplied to the liquid flow path on the side opposite to the injection hole plate in the first direction with respect to the manifold. A liquid injection head characterized by being disposed of.

(3) A liquid injection head characterized in that a heater is disposed on the second surface of the manifold facing the third direction.

(4) An insulating sheet is interposed between the first surface of the manifold and the facing surface of the head chip facing the first surface of the manifold facing the third direction. Characterized liquid injection head.

(5) The head chip, the manifold, and the drive board constitute a head module, and a plurality of the head modules are mounted on a base member in a state of being arranged in the third direction, and a plurality of injection hole plates are provided. A liquid injection characterized by having a plurality of the injection hole rows corresponding to the head chips in the head module and being arranged on a plate arrangement surface of the base member facing the other in the first direction. head.

(6) A spacer is interposed between the plate arranging surface of the base member and the surface of the injection hole plate facing the plate arranging surface of the base member facing the first direction. A liquid injection head characterized by that.

(7) The spacer is adhered to the base member with a soft adhesive, and the injection hole plate is adhered to the spacer with a hard adhesive formed of a material harder than the soft adhesive. A liquid injection head featuring.

(8) The other side of the first direction with respect to the injection hole plate has an exposed hole that exposes the injection hole row to the outside, and the injection hole guard that covers the injection hole plate from the other side of the first direction. Is arranged, the injection hole plate is formed smaller than the outer shape of the spacer in the plan view seen from the first direction, and the injection hole guard is the injection hole plate in the plan view seen from the first direction. A liquid injection head characterized in that it is adhered to the spacer in a region outside the area, and the bonding portion between the injection hole guard and the spacer surrounds the periphery of the injection hole plate.

(9) The plurality of head modules include a first head module capable of discharging a first liquid and a second head module capable of discharging a second liquid different in color from the first liquid, and the injection thereof. The injection hole plate is placed in a portion of the hole plate located between the first injection hole row corresponding to the first head module and the second injection hole row corresponding to the second head module. It is characterized in that a slit is formed so as to penetrate in the first direction and partition the first injection hole row and the second injection hole row, and the injection hole guard is adhered to the spacer through the slit. Liquid injection head.

(10) In the base member, the base member is penetrated in the first direction, and a mounting opening into which the head module is inserted is formed, and the head module and the base member are separated from each other. A liquid injection head characterized in that an urging member for urging the head module and the base member is interposed in at least one of a second direction and the third direction.

1 ... Inkjet printer (liquid sprayer)
5A, 5B ... Inkjet head (liquid injection head)
51 ... Head tip 52, 210, 320 ... Manifold 53 ... Drive board (heating mechanism)
57 ... Discharge channel 72, 200, 302 ... Flow path member 71,201, 301 ... Ink flow path (liquid flow path)
85 ... Heater (heating mechanism)
202 ... Ink pool (liquid pool)
203 ... Upstream main flow path (main flow path)
204 ... Downstream main flow path (main flow path)
305 ... Communication opening 308 ... Film member 322 ... Escape hole 325 ... Chamfered part 330 ... Accommodating recess

Claims (10)

With a head tip that has a channel filled with liquid,
A manifold that supports the head chip and has a liquid flow path that communicates with the channel.
A heating mechanism supported by the manifold and heating the liquid in the liquid flow path,
Equipped with
The manifold is
An inflow port that communicates with the liquid flow path and allows the liquid to flow into the liquid flow path.
A communication unit that communicates the liquid that has flowed through the liquid flow path so as to supply the liquid to the head chip.
A flow path member having a first surface on which the head tip is supported,
Equipped with
The liquid flow path is formed so as to meander and extend from the inflow port toward the communication portion, and also penetrates the flow path member in the normal direction of the first surface and has a plurality of the above. It has a communication opening that communicates collectively with the channel.
The communication opening is closed by a film member arranged on a second surface of the flow path member facing away from the first surface in the normal direction.
The film member is arranged at a position facing the head chip with the flow path member interposed therebetween.
A liquid injection head characterized by that. The liquid injection head according to claim 1, wherein the heating mechanism is a heater. The liquid injection head according to claim 1 or 2, wherein the heating mechanism is a drive substrate electrically connected to the head chip. The liquid injection head according to any one of claims 1 to 3, wherein a coating film having corrosion resistance to a liquid is formed on at least the inner surface of the liquid flow path in the manifold. The liquid flow path is
With the main flow path
A liquid pool that communicates with the main flow path and stores liquid,
The liquid injection head according to any one of claims 1 to 4, wherein the liquid injection head has. The liquid injection head according to any one of claims 1 to 5, wherein the film member has flexibility. The liquid injection head according to claim 6 , wherein the manifold includes a film retainer that sandwiches the film member with the flow path member in the normal direction. In the film retainer, a relief hole that allows bending and deformation of the film member is formed at a position that overlaps with the communication opening when viewed from the normal direction.
The liquid injection head according to claim 7 , wherein a chamfered portion is formed in a portion of the opening edge of the escape hole facing the film member in the normal direction. 7 . The liquid injection head described. A liquid injection device comprising the liquid injection head according to any one of claims 1 to 9 .

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