JP5701192B2 - Inkjet recording apparatus and method for removing recording medium in inkjet recording apparatus - Google Patents

Description

  The present invention relates to an ink jet recording apparatus that ejects ink from a recording head onto a recording medium and records an image on the recording medium, and more particularly to a technique for protecting the ink ejection surface of the recording head.

In general, an ink jet recording apparatus is known that ejects ink from a recording head onto a sheet (recording medium) to record an image on the sheet. The ink jet recording apparatus is used as, for example, a printer apparatus, a copying machine, a facsimile apparatus, or a complex machine thereof.
As one type of ink jet recording apparatus, there is a so-called line head type ink jet recording apparatus including a recording head of each color fixed along a paper conveyance path. In this type of ink jet recording apparatus, a sheet is conveyed by a sheet conveying belt in a state of facing the ink ejection surface of each recording head, and ink is ejected from each recording head onto the sheet being conveyed.

Incidentally, in the ink jet recording apparatus, a jam (paper jam) may occur on the paper transport path. When a jam occurs, the user performs a jam process to open the housing and remove the paper remaining on the paper transport path. If the user's hand or paper comes into contact with the ink discharge surface of the recording head during the jam processing by the user, the ink discharge surface may be damaged and the ink discharge port (nozzle) may be clogged, resulting in a decrease in print quality. is there.
On the other hand, for example, Patent Document 1 discloses a technique in which a paper conveying belt is separated from a recording head when a jam occurs, and the ink ejection surface of the recording head is covered with a shutter that moves in parallel to the ink ejection surface to protect it. It is disclosed.

JP 2005-96187 A

However, even when the paper transport belt is separated from the recording head when a jam occurs, the paper may remain attached to the recording head. In this case, if the ink discharge surface of the recording head is covered with the shutter described above, the paper may be rubbed against the ink discharge surface when the shutter pushes the paper, and the ink discharge surface may be damaged. Further, when the state where the sheet is adhered to the ink ejection surface continues, the ink flows out due to a capillary phenomenon, and there is a problem that the ink is consumed wastefully and the inside of the apparatus becomes dirty.
Accordingly, the present invention has been made in view of the above circumstances, and an object of the present invention is to provide an ink jet recording apparatus and an ink jet recording which can reliably separate the recording medium from the ink discharge surface of the recording head when a jam occurs. An object of the present invention is to provide a recording medium detaching method in an apparatus.

In order to achieve the above object, the present invention is configured as an ink jet recording apparatus comprising the following components (1) to (5).
(1) A recording head provided with an ink discharge surface for discharging ink.
(2) A transport unit that transports the recording medium while facing the ink ejection surface.
(3) First moving means for moving the recording head and the transport unit relatively to separate and approach the recording head and the transport unit.
(4) A protruding member disposed at a position facing the surface on the recording head side of the recording medium conveyed by the conveyance unit.
(5) The recording head and the projecting member are moved relatively to change the projecting member from the recording head side toward the transport unit side so that it protrudes from the ink ejection surface and does not project. Two moving means.
According to the present invention, the ejecting member is caused to project from the ink ejection surface from the recording head side toward the transport unit side by the second moving unit, whereby the recording medium is ejected from the ink ejection surface by the ejecting member. Can be reliably pulled away from the surface. Therefore, for example, by separating the recording medium from the ink discharge surface when a jam occurs, it is possible to prevent the recording medium from being rubbed against the ink discharge surface during the jam processing and damaging the ink discharge surface. Further, when the protruding member protrudes from the ink discharge surface, the protruding member functions as a barrier to contact with the ink discharge surface. Therefore, it is possible to prevent the user's hand or the recording medium from coming into contact with the ink ejection surface during the jam processing. By protecting the ink discharge surface in this manner, clogging of the ink discharge port (nozzle) of the ink discharge surface can be prevented. Furthermore, by avoiding contact between the ink ejection surface and the recording medium, it is possible to prevent wasteful ink flow from the ink ejection surface due to capillary action.

More specifically, a jam detection unit that detects the occurrence of a jam in the recording medium, and the recording head is detected by the first moving unit when the occurrence of a jam in the recording medium is detected by the jam detection unit. And a movement control means for separating the conveying unit and changing the protruding member from the recording head side to the conveying unit side so as to protrude from the ink discharge surface by the second moving means. A configuration to be provided is considered. Accordingly, the recording medium can be automatically separated from the ink ejection surface when a jam occurs.
Here, the second moving means moves the protruding member from the recording head side toward the conveying unit side in conjunction with the separation operation of the recording head and the conveying unit by the first moving means. It is conceivable to change the state so as to protrude from the ink discharge surface. For example, in a configuration in which the transport unit is disposed below the recording head, the first moving unit moves the transport unit up and down relative to the recording head, and the second moving unit includes: It is a support part which is provided in the said conveyance unit and supports the said protrusion member from the downward direction. As a result, the protruding member moves up and down with respect to the recording head as the transport unit moves up and down. Therefore, it is not necessary to provide separate driving means for moving the protruding member, and the number of components can be reduced.

The apparatus further comprises interlocking switching means for switching presence / absence of interlocking between the separation operation of the recording head and the transport unit by the first moving means and the operation of changing the protruding member to a state of protruding from the ink ejection surface. Can be considered. For example, the interlock switching unit includes an electromagnet that attracts the projecting member with a magnetic force generated by energization and maintains the projecting member in a state of not projecting from the ink ejection surface, and an energization control unit that switches whether the electromagnet is energized or not. , Has. This makes it possible to arbitrarily switch the presence or absence of the interlock.
Specifically, the interlock switching means validates the interlock when the jam detection means detects the occurrence of a jam in the recording medium, and invalidates the interlock when the recording head maintenance is started. It is thought that it is what to do. Thus, when maintenance such as purging (cleaning) of the ink discharge surface of the recording head is performed, the protrusion is not maintained and the protrusion member does not protrude from the ink discharge surface. Does not get in the way. Further, when a jam occurs, the interlocking is effective and the protruding member protrudes from the ink discharge surface, so that the recording medium can be reliably pulled away from the ink discharge surface by the protruding member.

  By the way, the present invention can also be understood as a recording medium detaching method in an ink jet recording apparatus. That is, according to the present invention, the recording head provided with the ink ejection surface for ejecting ink and the transport unit for transporting the recording medium while facing the ink ejection surface are relatively moved, so that the recording head and the transport The unit is separated, and the projecting member disposed at a position facing the recording head side surface of the recording medium transported by the transport unit and the recording head are relatively moved to move the projecting member. It can be understood as a recording medium detachment method in an ink jet recording apparatus, wherein the state is changed from the recording head side toward the transport unit side so as to protrude from the ink ejection surface.

  According to the present invention, the recording medium can be reliably pulled away from the ink discharge surface of the recording head when a jam occurs in the ink jet recording apparatus. Thereby, for example, the ink discharge surface can be protected and jamming can be prevented during the jam processing.

1 is a schematic cross-sectional view showing a schematic configuration of an ink jet recording apparatus X1 according to a first embodiment of the present invention. 1 is a schematic cross-sectional view showing a schematic configuration of an ink jet recording apparatus X1 according to a first embodiment of the present invention. FIG. 3 is a schematic diagram of a main part for explaining a sheet separating mechanism of the inkjet recording apparatus X1 according to the first embodiment of the present invention. The schematic diagram which shows the EE arrow cross section in FIG. 2A. FIG. 3 is a schematic diagram of a main part for explaining a sheet separating mechanism of the inkjet recording apparatus X1 according to the first embodiment of the present invention. The schematic diagram which shows the FF arrow cross section in FIG. 3A. The schematic diagram which shows the GG arrow cross section in FIG. 3A. 6 is a flowchart illustrating an example of a procedure of a jam occurrence process executed by the inkjet recording apparatus X1 according to the first embodiment of the present invention. FIG. 6 is a schematic cross-sectional view showing a schematic configuration of an inkjet recording apparatus X2 according to a second embodiment of the present invention. FIG. 6 is a schematic cross-sectional view showing a schematic configuration of an inkjet recording apparatus X2 according to a second embodiment of the present invention. The principal part schematic diagram for demonstrating the paper separation mechanism of the inkjet recording device X2 which concerns on 2nd Embodiment of this invention. The schematic diagram which shows the HH arrow cross section in FIG. 6A. FIG. 10 is a schematic diagram of a main part for explaining the operation of a sheet separating mechanism of an inkjet recording apparatus X2 according to a second embodiment of the present invention. FIG. 10 is a schematic diagram of a main part for explaining the operation of a sheet separating mechanism of an inkjet recording apparatus X2 according to a second embodiment of the present invention. 10 is a flowchart illustrating an example of a procedure of a purge start process executed by the inkjet recording apparatus X2 according to the second embodiment of the present invention. The figure which shows the protrusion bar 362A which is another example of the protrusion bar 362 in the inkjet recording device X2 which concerns on 2nd Embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the accompanying drawings for understanding of the present invention. In addition, the following embodiment is an example which actualized this invention, Comprising: The thing of the character which limits the technical scope of this invention is not.

<First Embodiment>
First, an ink jet recording apparatus X1 (hereinafter abbreviated as “recording apparatus X1”) according to a first embodiment of the present invention will be described with reference to FIGS. 1A shows a state where the recording apparatus X1 can print, and FIG. 1B shows a state during the jam processing of the recording apparatus X1.
As shown in FIG. 1, the recording apparatus X1 includes a paper feed cassette 1, a paper feed unit 2, an image forming unit 3, an ink tank unit 4, a transport unit 5, a lifting mechanism 6, a paper discharge unit 7, a control unit 8, And a main body frame 10 that accommodates or supports them.
The recording device X1 is a printer device that executes print processing based on image data input from an information processing device such as a personal computer. The ink jet recording apparatus according to the present invention can be applied not only to a printer apparatus but also to a copying machine, a facsimile machine, a multifunction machine, and the like.

The paper feed cassette 1 accommodates paper P (an example of a recording medium) to be printed in the recording apparatus X1. Of course, the printing target is not limited to paper, but may be a recording medium such as an OHP sheet or cloth.
The paper feed unit 2 includes a pickup roller 21, a transport roller 22, a transport path 23, a registration roller 24, a manual feeder 25, and a paper feed roller 26. The pickup roller 21 takes out the sheets P from the sheet feeding cassette 1 one by one. The transport roller 22 and the transport path 23 transport the paper P taken out by the pickup roller 21 to the registration roller 24. The registration roller 24 conveys the paper P to the image forming unit 3 at a predetermined conveyance timing (image writing timing). The manual feeder 25 and the paper feed roller 26 are used for supplying paper P from the outside.

The image forming unit 3 includes recording heads 31, 32, 33, and 34 corresponding to colors of K (black), C (cyan), M (magenta), and Y (yellow), and a head frame 35 that supports these. have. The head frame 35 is supported by the main body frame 10. In the present embodiment, a configuration having four recording heads 31 to 34 corresponding to four colors of KCMY will be described as an example, but the number of recording heads is not limited to this.
The recording heads 31 to 34 are elongated in a direction perpendicular to the transport direction of the paper P (paper width direction), and are fixed in order along the transport direction of the paper P at predetermined intervals. ing. In addition, ink discharge surfaces 31 </ b> A to 34 </ b> A each having a large number of nozzles (discharge ports) for discharging ink are provided at the lower ends of the recording heads 31 to 34.
In the image forming unit 3, an image is recorded on the paper P by ejecting ink from the ink ejection surfaces 31 </ b> A to 34 </ b> A onto the paper P transported by the transport unit 5. That is, the recording apparatus X1 is a so-called line head type ink jet recording apparatus. As the ink ejection method of the recording heads 31 to 34, for example, a piezo method that ejects ink using a piezo element or a thermal method that ejects ink by generating bubbles by heating is employed.
The ink tank unit 4 includes ink tanks 41, 42, 43, and 44 in which inks corresponding to the colors K, C, M, and Y are stored. The ink tanks 41 to 44 are connected to the recording heads 31 to 34 of the same color by ink tubes (not shown), respectively, and replenish ink to the recording heads 31 to 34. Note that air exists above the ink in the ink tanks 41 to 44, and the ink liquid level in the ink tanks 41 to 44 is lower than the ink ejection surfaces 31A to 34A of the recording heads 31 to 34. It has been adjusted to be.

The transport unit 5 is disposed below the recording heads 31 to 34, and transports the paper P while facing the ink ejection surfaces 31A to 34A. Specifically, the transport unit 5 includes a paper transport belt 51 on which the paper P is placed, stretching rollers 52 to 54 that stretch the paper transport belt 51, and a transport frame 55 that supports them. ing. The gap between the paper transport belt 51 and the ink ejection surfaces 31A to 34A is determined so that the gap between the surface of the paper P and the ink ejection surfaces 31A to 34A is, for example, 1 mm.
The tension roller 52 is connected to a rotating shaft of a motor (not shown). The tension roller 52 rotates counterclockwise by driving the motor and causes the paper transport belt 51 to travel in the direction of the arrow (the direction from right to left in FIG. 1). As a result, the paper P supplied from the paper feeding unit 2 is transported to the paper discharge unit 7 through the image forming unit 3 by the travel of the paper transport belt 51.
The transport unit 5 is also provided with a suction unit (not shown) that sucks air from a large number of through holes formed in the transport belt 51 so as to attract the paper P to the paper transport belt 51. Yes. In addition, a roller 56 is provided at a position opposite to the stretching roller 53 to press the paper P against the paper transport belt 51 and transport it.

The lifting mechanism 6 supports the transport unit 5 from below and lifts the transport unit 5 up and down with respect to the recording heads 31 to 34. That is, the elevating mechanism 6 moves the transport unit 5 and the recording heads 31 to 34 relative to each other to move the transport unit 5 and the recording heads 31 to 34 apart and approach each other. Here, the elevating mechanism 6 is an example of a first moving means.
Specifically, the elevating mechanism 6 includes four pairs of eccentric cams 61 corresponding to the four corners of the bottom surface of the transport unit 5, a rotating shaft 62, and a bearing group 63. The eccentric cam 61 is rotatably supported by the rotating shaft 62, and the rotating shaft 62 is connected to a rotating shaft of a motor (not shown). The bearing group 63 includes a plurality of bearings supported by the eccentric cam 61 with a part of the bearing group 63 protruding outward from the outer peripheral edge of the eccentric cam 61. The transport unit 5 is supported from below by a bearing having the highest vertical position among a plurality of bearings provided in the bearing group 63.

In the elevating mechanism 6, the eccentric cam 61 rotates when the rotating shaft 62 is rotationally driven by a motor (not shown). At this time, with the rotation of the eccentric cam 61, the bearings having the highest vertical position among the bearings provided in the bearing group 63 are sequentially switched. As a result, the bearings that support the transport unit 5 from below are switched, and the transport unit 5 moves up and down in the vertical direction.
For example, in FIG. 1, the left eccentric cam 61 is rotated clockwise and the right eccentric cam 61 is rotated counterclockwise, whereby the transport unit 5 is gradually lowered. In FIG. 1, the left eccentric cam 61 is rotated counterclockwise and the right eccentric cam 61 is rotated clockwise, whereby the transport unit 5 is gradually raised. In addition, when the bearings that support the transport unit 5 in the bearing group 63 are switched, a state in which the transport unit 5 is simultaneously supported by two adjacent bearings is passed.

Here, FIG. 1A shows a state in which the transport unit 5 is supported by a bearing farthest from the rotating shaft 62 in the bearing group 63. This state is a state in which the vertical position of the transport unit 5 is the highest and the transport unit 5 is closest to the recording heads 31 to 34 (hereinafter referred to as “normal position”). When the transport unit 5 is in this normal position, the recording apparatus X1 can perform a printing operation.
FIG. 1B shows a state in which the transport unit 5 is supported by a bearing closest to the rotating shaft 62 in the bearing group 63. This state is a state where the vertical position of the transport unit 5 is the lowest and the transport unit 5 is the farthest away from the recording heads 31 to 34 (hereinafter referred to as “retraction position”). When the transport unit 5 is in the retracted position, the user can perform a jam process for removing the paper P remaining in the transport unit 5.
Note that the transport unit 5 is not limited to be moved up and down with respect to the recording heads 31 to 34 as long as the transport unit 5 and the recording heads 31 to 34 can be separated and approached. For example, a configuration in which the recording heads 31 to 34 are moved up and down, or a configuration in which the transport unit 5 and the recording heads 31 to 34 are moved up and down are also conceivable as other embodiments. Further, the configuration of the lifting mechanism 6 is not limited to that described here. For example, a configuration in which the elevating mechanism 6 elevates and lowers the transport unit 5 using a ball screw or a rack and a pinion is conceivable.

The paper discharge unit 7 is provided on the downstream side of the image forming unit 3 in the paper conveyance direction, and includes a drying device 71, a conveyance path 72, a paper discharge roller 73, a paper discharge tray 74, and the like. The drying device 71 dries the ink attached to the paper P by blowing air onto the paper P, for example. Then, the paper P dried by the drying device 71 is discharged to the paper discharge tray 74 by the paper discharge roller 73 through the transport path 72.
The control unit 8 has a control device such as a CPU which is an arithmetic unit, a RAM used as a temporary storage area, and a ROM in which various control programs are stored in advance. The control unit 8 controls each component of the recording apparatus X1 based on image data input from the outside, thereby recording an image corresponding to the image data on the paper P. Further, the control unit 8 executes a jam occurrence process (see FIG. 4) described later.

  Next, the paper detaching mechanism provided in the recording apparatus X1 will be described with reference to FIGS. 2A and 3A are schematic views of the main part of the image forming unit 3 as viewed from the upstream side in the paper conveyance direction. FIG. 2A is a state in which the conveyance unit 5 is in the normal position, and FIG. The state in which the conveyance unit 5 exists in the said retracted position is shown. 2B is a schematic view showing a cross section taken along the line EE in FIG. 2A, FIG. 3B is a schematic view showing a cross section taken along the line FF in FIG. 3A, and FIG. 3C shows a cross section taken along the line GG in FIG. It is a schematic diagram.

As shown in FIGS. 2 and 3, on the surface of the recording heads 31 to 34 of the image forming unit 3 on the surface on the recording heads 31 to 34 side of the paper P transported by the transport unit 5. At opposite positions, a protrusion member 36 for separating the paper P from each of the ink discharge surfaces 31A to 34A is provided. The protruding member 36 is a resin member whose outer shape is a flat rectangular shape. The protruding member 36 includes blades 37A to 37E positioned upstream and downstream in the paper transport direction of the recording heads 31 to 34, and openings 38A corresponding to the positions of the recording heads 31 to 34, respectively. To 38D.
Further, both ends of the protruding member 36 in the direction perpendicular to the sheet conveying direction are placed on the upper end of the conveying frame 55 of the conveying unit 5 and are supported from below by the conveying frame 55 (an example of a supporting portion). (See FIG. 2A). Accordingly, when the transport unit 5 moves up and down in the vertical direction, the protruding member 36 supported by the transport unit 5 moves up and down in conjunction with the lifting operation of the transport unit 5. Here, the transport frame 55 that supports the protruding member 36 from below is an example of a second moving unit. In addition, it is also conceivable as another embodiment that the protrusion member 36 is moved using a ball screw or a rack and a pinion that are interlocked with the lifting and lowering operation of the transport unit 5 by the lifting mechanism 6.

When the protruding member 36 moves up and down with respect to the recording heads 31 to 34, the positional relationship between the recording heads 31 to 34 and the protruding member 36 moves relatively. Accordingly, the blades 37A to 37E of the protrusion member 36 protrude from the ink discharge surfaces 31A to 34A toward the transport unit 5 from the recording heads 31 to 34 (see FIG. 3) and do not protrude. (See FIG. 2).
The main body frame 10 is provided with a stopper 39 for setting a lower limit position of the protruding member 36. Thereby, the downward movement of the protruding member 36 is locked by the stopper 39 (see FIG. 3A). The stopper 39 is at a position where at least the blades 37A to 37D of the protruding member 36 protrude from the ink discharge surfaces 31A to 34A from the recording heads 31 to 34 toward the transport unit 5. Is provided.
By the way, if the blades 37A to 37E of the protruding member 36 can be changed between a state of protruding from the ink discharge surfaces 31A to 34A and a state of not protruding, the protruding member 36 is moved with respect to the recording heads 31 to 34. It is not restricted to the structure to raise / lower. For example, a configuration in which the recording heads 31 to 34 are moved up and down, or a configuration in which the protruding member 36 and the recording heads 31 to 34 are moved up and down are also conceivable as other embodiments.

  Next, a jam occurrence process (see FIG. 4) executed by the control unit 8 in the recording apparatus X1 will be described. Here, S11, S12,... Shown in the figure indicate processing procedure (step) numbers. The control unit 8 when executing the following jam occurrence process corresponds to the movement control means. Further, the method of separating the paper P from the ink discharge surfaces 31A to 34A by executing the following processes at the time of jam occurrence corresponds to the recording medium removing method in the ink jet recording apparatus according to the present invention.

(Step S11)
First, in step S11, the control unit 8 waits for jamming of the paper P in the recording apparatus X1 (No side of S11). The control unit 8 detects the jam of the paper P based on the detection results of a plurality of paper detection sensors (not shown) arranged on the transport path of the paper P.
For example, the control unit 8 detects the width of the paper P with paper detection sensors (not shown) provided at a plurality of locations on the transport path of the paper P, and generates a jam when the width is different. It is possible to detect. The control unit 8 detects the passage of the paper P by paper detection sensors (not shown) provided at a plurality of locations on the transport path of the paper P, and the detection timing of the passage is determined from a predetermined timing. It is conceivable to detect the occurrence of a jam when there is a deviation. Here, the control unit 8 when detecting the occurrence of a jam of the paper P corresponds to a jam detecting means.

(Step S12)
In step S11, when occurrence of a jam of the paper P is detected (Yes in S11), the process proceeds to step S12. In step S <b> 12, the control unit 8 drives the lifting mechanism 6 to start the lowering operation of the transport unit 5 and separates the transport unit 5 and the recording heads 31 to 34. Specifically, the control unit 8 drives the lifting mechanism 6 by driving a motor (not shown) connected to the rotating shaft 62 of the lifting mechanism 6.
At this time, the protruding member 36 is lowered by its own weight while being supported by the transfer frame 55 of the transfer unit 5 as the transfer unit 5 is lowered as described above. The lowering of the protruding member 36 continues until it is locked by the stopper 39. As a result, each of the blades 37A to 37E of the protrusion member 36 protrudes from the ink discharge surfaces 31A to 34A from at least the recording heads 31 to 34 toward the transport unit 5.
Therefore, when the paper P adheres to the ink discharge surfaces 31A to 34A, the blades 37A to 37D of the protruding member 36 move onto the paper P when moving below the ink discharge surfaces 31A to 34A. The sheet P is brought into contact and moved vertically downward. Accordingly, the paper P is reliably pulled away from the ink ejection surfaces 31A to 34A. In addition, since the separation of the paper P is performed by moving vertically downward, the paper P is also prevented from rubbing against the ink ejection surfaces 31A to 34A during the separation.
In the present embodiment, the lifting / lowering operation of the transport unit 5 and the lifting / lowering operation of the protruding member 36 are performed simultaneously. On the other hand, the structure which performs the raising / lowering operation | movement of the said conveyance unit 5 and the raising / lowering operation | movement of the said protrusion member 36 by a separate drive means is also considered. In this case, the lowering operation of the transport unit 5 and the lowering operation of the protruding member 36 may be executed individually in this order.

(Steps S13 to S14)
The descending operation of the elevating mechanism 6 continues until the control unit 8 detects that the transport unit 5 has reached the retracted position (see FIG. 1B) in the subsequent step S13 (No side of S13). . The control unit 8 detects that the transport unit 5 has reached the retracted position, for example, based on a detection result of an optical sensor (photo sensor) (not shown) or an elapsed time of a descent operation.
Here, if it is detected that the transport unit 5 has reached the retracted position (Yes side of S13), the process proceeds to step S14. In step S <b> 14, the control unit 8 stops the lowering operation of the transport unit 5 by controlling the lifting mechanism 6. Specifically, the control unit 8 stops driving of the lifting mechanism 6 by stopping a motor (not shown) connected to the rotating shaft 62 of the lifting mechanism 6.
When the lowering operation of the transport unit 5 is stopped, the control unit 8 unlocks the maintenance door (not shown) of the main body frame 10 that is opened and closed during the jam processing. Thus, the user can open the maintenance door (not shown) and perform jam processing. Thereafter, when it is detected that the jam processing is finished and the maintenance door (not shown) is closed, the control unit 8 raises the transport unit 5 to the normal position by the lifting mechanism 6 (see FIG. 1A). ).

  As described above, in the recording apparatus X1, the paper P is pulled away from the ink ejection surfaces 31A to 34A of the recording heads 31 to 34 vertically downward by the protruding member 36 when a jam occurs. Accordingly, it is possible to prevent the paper P from rubbing against the ink ejection surfaces 31A to 34A during the jam processing performed by the user thereafter. Further, during the jam processing, the protruding member 36 protrudes from the outer periphery of the ink discharge surfaces 31A to 34A. For this reason, it is possible to prevent the user's hand performing the jam processing from directly contacting the ink discharge surfaces 31A to 34A, thereby protecting the ink discharge surfaces 31A to 34A and preventing the user's hands from being soiled. In addition, since the continuation of the adhesion state of the paper P to the ink discharge surfaces 31A to 34A is avoided, wasteful flow of ink from the ink discharge surfaces 31A to 34A due to a capillary phenomenon or the like is prevented.

Second Embodiment
Next, an ink jet recording apparatus X2 (hereinafter abbreviated as “recording apparatus X2”) according to a second embodiment of the present invention will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected about the component similar to the said recording apparatus X1, and the description is abbreviate | omitted. Here, FIG. 5A shows a state in which the recording apparatus X2 can print, and FIG. 5B shows a state in which the recording apparatus X2 is performing a purge operation.

As shown in FIG. 5, the recording apparatus X <b> 2 includes a purge apparatus 9 that recovers the functions of the ink ejection surfaces 31 </ b> A to 34 </ b> A of the recording heads 31 to 34. The purge device 9 is supported by a horizontal movement mechanism (not shown) so as to be movable in the horizontal direction (left-right direction in FIG. 5). The horizontal movement mechanism (not shown), for example, moves the purge device 9 in the horizontal direction by using a drive mechanism such as a ball screw or a rack and a pinion that converts a rotational movement of a gear connected to a rotation shaft of a motor into a linear movement. It is a conventionally well-known drive mechanism to move to.
The purge device 9 is configured to clean a plurality of cap members (not shown) that receive ink ejected from the ink ejection surfaces 31A to 34A of the recording heads 31 to 34, and a plurality of ink ejection surfaces 31A to 34A. A wiper member (not shown) is included.

Then, after the transport unit 5 is moved to the retracted position by the elevating mechanism 6, the purge device 9 moves to a space generated at a position opposite to the recording heads 31 to 34 (see FIG. 5B).
When the purge device 9 moves to a position opposite to the recording heads 31 to 34, ink is ejected from the ink ejection surfaces 31A to 34A to the cap members (not shown) with a pressure stronger than usual, and the ink ejection Clogging on the surfaces 31A to 34A is eliminated. The ink discharged to the cap member is discharged from a discharge port provided at the bottom of the cap member to a predetermined waste ink storage unit.
Thereafter, the purge device 9 drives each of the wiper members (not shown) by driving means such as a motor to elastically contact the ink discharge surfaces 31A to 34A, thereby bringing the ink discharge surfaces 31A to 34A into contact with each other. to clean up. The wiper member (not shown) cleans the ink ejection surfaces 31A to 34A by moving in the short direction of the recording heads 31 to 34. Of course, the configuration of the purge device 9 is not limited to this, and various conventionally known purge devices or cleaning devices may be used.

Next, the sheet detachment mechanism provided in the recording apparatus X2 will be described with reference to FIGS. Here, FIG. 6A is a schematic diagram of a main part of the image forming unit 3 as viewed from the upstream side in the paper conveyance direction, and FIG. 6B is a schematic diagram showing a cross section taken along the line HH in FIG. 6A. 7A shows a state where the transport unit 5 is in the normal position, and FIG. 7B shows a state where the transport unit 5 is in the retracted position.
As shown in FIGS. 6A and 6B, in the image forming unit 3 of the recording apparatus X2, the recording heads 31, 32, 33, and 34 have three recording heads 311 to 313, 314 to 316, and 317 to 319, respectively. 320-322. The recording heads 311 to 322 are arranged in a zigzag shape in plan view, and are supported by the head frame 35.
Hereinafter, for convenience of explanation, the recording heads 311 to 313, 314 to 316, 317 to 319, and 320 to 322 are collectively referred to as recording heads 31, 32, 33, and 34, respectively, and these ink ejection surfaces are referred to as ink ejection surfaces. They are referred to as 31A, 32A, 33A, and 34A.
The recording device X2 includes a protruding member 36A and an electromagnet 365 as shown in FIGS. 6A and 6B. The protruding member 36 </ b> A is disposed at a position that is a peripheral portion of the recording heads 311 to 322 and faces the recording head 31 to 34 side surface of the paper P conveyed by the conveyance unit 5. A plate 361, a protruding bar 362, a support plate 363, a stopper 364, and the like are included. The electromagnet 365 is supported on the main body frame 10.

The upper plate 361 is a metal flat member that is attracted by the magnetic force of the electromagnet 365. The upper plate 361 may be a resin member in which a metal plate is bonded only at a position corresponding to the electromagnet 365.
As shown in FIG. 6B, the protruding bar 362 is provided corresponding to the gap between the recording heads 311 to 322, respectively. Each of the protruding bars 362 is a bottomed cylindrical resin member joined to the lower surface of the upper plate 361. The bottom surface of the protruding bar 362 is screwed to the upper plate 361 with screws. Further, the tip of the protruding bar 362 on the transport unit 5 side is formed in a hemispherical shape.
The support plates 363 are provided at the four corners of the upper plate 361, respectively. Each of the support plates 363 is a bottomed rectangular cylindrical resin member joined to the lower surface of the upper plate 361 in the same manner as the protruding bar 362. Here, the support plate 363 is longer than the protruding bar 362, and the lower end thereof is in contact with the upper end of the transport frame 55 of the transport unit 5. Accordingly, the entire protruding member 36 </ b> A is supported from below by the transport frame 55 of the transport unit 5.
The stopper 364 is a protrusion formed on the outer peripheral surface of the support plate 363, and determines the lower limit position of the protruding member 36A. The stopper 364 contacts the head frame 35 when the protruding member 36A moves downward. Thereby, the downward movement of the protruding member 36 </ b> A is locked by the contact of the stopper 364 and the head frame 35 at the position of the stopper 364.
The electromagnet 365 is switched between the presence and absence of a magnetic force according to the presence or absence of energization. Specifically, the electromagnet 365 generates a magnetic force temporarily when energized to attract the upper plate 361 of the protruding member 36A. Note that whether or not the electromagnet 365 is energized is controlled by the control unit 8, and the electromagnet 365 is not energized in the initial state.

FIG. 7 shows a state in which the transport unit 5 is lowered and moved to the retracted position. FIG. 7A shows a state where the electromagnet 365 is not energized, and FIG. 7B shows a state where the electromagnet 365 is energized. Shows the case.
As shown in FIG. 7A, when the electromagnet 365 is not energized, the protruding member 36 </ b> A descends by its own weight in conjunction with the descending operation of the transport unit 5.
On the other hand, as shown in FIG. 7B, if the electromagnet 365 is energized, a magnetic force is generated in the electromagnet 365 and the upper plate 361 is attracted to the electromagnet 365. Accordingly, the protruding member 36 </ b> A is maintained in a state where it does not protrude from the ink discharge surfaces 31 </ b> A to 34 </ b> A by the electromagnet 365, and does not descend in conjunction with the descending operation of the transport unit 5. That is, the movement of the protruding member 36A is restricted (prohibited) by the electromagnet 365. As described above, the electromagnet 365 is operated to separate the recording heads 31 to 34 and the transport unit 5 by the lifting mechanism 6 and to change the protruding member 36A to protrude from the ink discharge surfaces 31A to 34A. Switch the presence or absence of linking. Here, the electromagnet 365 is an example of an interlocking switching unit.
Therefore, in the recording apparatus X2, the control unit 8 can arbitrarily switch whether or not the protruding member 36A can be lowered by switching whether or not the electromagnet 365 is energized. Here, the control unit 8 for switching whether or not the electromagnet 365 is energized corresponds to an energization control means.

Specifically, also in the recording apparatus X2, the control unit 8 executes the jam occurrence processing (see FIG. 4). At this time, when a jam is detected in the jam occurrence process, the control unit 8 does not energize the electromagnet 365. For this reason, when a jam occurs, the separating operation of the recording heads 31 to 34 and the transport unit 5 by the lifting mechanism 6 and the operation of changing the protruding member 36A to a state of protruding from the ink discharge surfaces 31A to 34A are linked. It becomes effective. Accordingly, the sheet P can be reliably pulled away from the ink discharge surfaces 31A to 34A by the protruding bar 362 as the protruding member 36A descends. At this time, the contact between the protruding bar 362 and the paper P is made by point contact at the hemispherical top portion which is the tip of the protruding bar 362. Therefore, the contact area between the protruding bar 362 and the paper P is small, and adhesion of ink from the paper P to the protruding bar 362 can be prevented. In addition, it is conceivable that the paper P contacts not only the hemispherical top that is the tip of the protruding bar 362 but also the periphery of the top, but this contact is the hemispherical spherical surface that is the tip of the protruding bar 362. Will be done in the department. Therefore, it is possible to prevent the paper P from being pressed and scratched and the paper P from being torn.
On the other hand, the control unit 8 performs the following purge start process (see FIG. 8), and when the maintenance such as the purge operation by the purge device 9 is started, after the electromagnet 365 is energized, The transport unit 5 is lowered. Hereinafter, the purge start process executed by the control unit 8 will be described with reference to FIG. Here, S21, S22,... Shown in the figure indicate processing procedure (step) numbers.

(Steps S21 to S22)
As shown in FIG. 8, the control unit 8 first waits for the start of the purge operation of the purge device 9 in step S21 (No side of S21). Here, the control unit 8 executes the purge operation by the purge device 9 every predetermined period set in advance or in response to a user operation.
Here, the start of the purge operation by the purge device 9 is taken as an example of the start of maintenance of the recording heads 31 to 34, but is not limited thereto, for example, the recording heads 31 to 34 or the ink ejection surfaces 31A to 34A. The same applies to the start of maintenance such as replacement and repair. A wiping operation in which only the recording heads 31 to 34 are cleaned by the wiper member (not shown) of the purge device 9 is an example of maintenance of the recording heads 31 to 34.
If it is determined in step S21 that the purge operation is started (Yes in S21), the process proceeds to step S22. In step S22, the control unit 8 starts energizing the electromagnet 365. As a result, the electromagnet 365 generates a magnetic force to attract the upper plate 361 of the protruding member 36A, and keeps the protruding member 36A from protruding from the ink discharge surfaces 31A to 34A.

(Steps S23-25)
In subsequent step S <b> 23, the control unit 8 starts the lowering operation of the transport unit 5 by driving the elevating mechanism 6. At this time, since the lowering of the protruding member 36A is prohibited by the electromagnet 365, only the transport unit 5 is lowered.
Thereafter, the lowering operation of the elevating mechanism 6 continues until the control unit 8 detects that the transport unit 5 has reached the retracted position (see FIG. 5B) in the subsequent step S24 (No side of S24). . When it is detected that the transport unit 5 has reached the retracted position (Yes side in S24), the process proceeds to step S25. In step S <b> 25, the control unit 8 stops the lowering operation of the transport unit 5 by stopping the driving of the elevating mechanism 6.

(Step S26)
In step S26, the control unit 8 causes the purge device 9 to perform a purge operation. Specifically, the control unit 8 starts the purge operation by the purge device 9 after moving the purge device 9 to the space at the opposite position of the recording heads 31 to 34 generated by the retraction of the transport unit 5. Let At this time, since the protruding bar 362 of the protruding member 36A is positioned above the ink discharge surfaces 31A to 34A, the purge operation by the purge device 9 is not hindered.
When the purge operation is completed, the control unit 8 moves the purge device 9 to the original position, and then raises the transport unit 5 to the normal position by the lifting mechanism 6 (see FIG. 5A). . When the transport unit 5 reaches the normal position, the control unit 8 stops energizing the electromagnet 365.

As described above, in the recording apparatus X2, when maintenance such as purging (cleaning) of the ink ejection surfaces 31A to 34A of the recording heads 31 to 34 is performed, the movement of the protruding member 36A is caused to move to the electromagnet 365. Prohibited by. Therefore, the protruding bar 362 of the protruding member 36A does not protrude from the ink discharge surfaces 31A to 34A, and the protruding bar 362 does not interfere with maintenance.
On the other hand, when a jam occurs, the paper P is reliably pulled away from the ink ejection surfaces 31A to 34A of the recording heads 31 to 34 by the protruding bar 362 of the protruding member 36A. Accordingly, it is possible to prevent the paper P from rubbing against the ink ejection surfaces 31A to 34A during the jam processing performed by the user thereafter. Further, during the jam processing, the protruding bar 362 of the protruding member 36A is in a state of protruding from the outer periphery of the ink discharge surfaces 31A to 34A. For this reason, it is possible to prevent the user's hand performing the jam processing from directly contacting the ink discharge surfaces 31A to 34A, thereby protecting the ink discharge surfaces 31A to 34A and preventing the user's hands from being soiled. In addition, since the continuation of the adhesion state of the paper P to the ink discharge surfaces 31A to 34A is avoided, wasteful flow of ink from the ink discharge surfaces 31A to 34A due to a capillary phenomenon or the like is prevented.

In the second embodiment, the case where the electromagnet 365 is used for switching whether or not the protrusion member 36A is movable has been described as an example. However, another configuration that exhibits the same function may be employed.
For example, a configuration in which whether or not the protrusion member 36A can move is conceivable by engaging / disengaging a part of the protrusion member 36A with an engaging portion connected to a driving unit such as a solenoid. In this case, the driving means and the engaging portion are an example of the interlock switching means.
Further, in the configuration in which the protrusion member 36A is lifted and lowered using a gear that is rotated by a driving force transmitted from a motor (not shown) of the lifting mechanism 6, the presence / absence of power transmission from the motor to the gear is switched by a clutch. It is possible. In this case, the clutch is an example of an interlocking switching unit.
Of course, as described in the second embodiment, the recording apparatus X1 according to the first embodiment adopts a configuration in which whether or not the protrusion member 36 is movable can be controlled by the interlock switching means such as the electromagnet 365. Are also considered as other embodiments.
Incidentally, as shown in FIGS. 6 and 7, the protruding bar 362 provided in the inkjet recording apparatus X2 has a hemispherical tip. On the other hand, the tip shape of the protruding bar 362 is not limited to a hemispherical shape, but may be another shape. For example, as shown in FIG. 9, instead of the protruding bar 362, it is conceivable to use a protruding bar 362A having a flat tip.

1: Paper feed cassette 2: Paper feed unit 3: Image forming units 31 to 34, 311 to 322: Recording heads 31 A to 34 A: Ink ejection surface 35: Head frame 36, 36 A: Extrusion members 37 A to 37 E: Blades 38 A to 38 D : Opening 39, 364: Stopper 361: Upper plate 362: Protruding bar 363: Support plate 4: Ink tank unit 5: Conveying unit 51: Paper conveying belts 52 to 54: Stretching roller 55: Conveying frame 6: Lifting mechanism 7 : Paper discharge unit 8: Control unit 9: Purge device 10: Main body frame

Claims (5)

A recording head provided with an ink ejection surface for ejecting ink;
A transport unit for transporting a recording medium while facing the ink ejection surface;
First moving means for relatively moving the recording head and the transport unit to separate and approach the recording head and the transport unit;
A projecting member disposed at a position facing the recording head side surface of the recording medium transported by the transport unit;
A second movement that relatively moves the recording head and the protruding member to change the protruding member from the recording head side toward the transport unit side in a state of protruding from the ink ejection surface and a state of not protruding. Means,
Jam detecting means for detecting occurrence of jam in the recording medium;
When the occurrence of a jam in the recording medium is detected by the jam detecting means, the recording head and the transport unit are separated by the first moving means, and the protruding member is moved by the second moving means. A movement control means for changing from a recording head side toward the transport unit side so as to protrude from the ink ejection surface;
Equipped with a,
The transport unit is disposed below the recording head,
The first moving means moves the transport unit up and down relative to the recording head,
The second moving means moves the ink ejection surface from the recording head side toward the transport unit side in conjunction with the separation operation of the recording head and the transport unit by the first moving means. An ink jet recording apparatus that is changed to a more protruding state and is a support portion that is provided in the transport unit and supports the protruding member from below . And further comprising an interlocking switching means for switching presence / absence of interlocking between the separation operation of the recording head and the transport unit by the first moving means and the operation of changing the protruding member to a state of protruding from the ink ejection surface. Item 10. The ink jet recording apparatus according to Item 1 . The interlock switching means includes: an electromagnet that attracts the protruding member with a magnetic force generated by energization to maintain the protruding member in a state not protruding from the ink discharge surface; and an energization control unit that switches whether the electromagnet is energized or not. The ink jet recording apparatus according to claim 2, which has the ink jet recording apparatus. The interlock switching means validates the interlock when the jam detection means detects the occurrence of a jam of the recording medium, and invalidates the interlock when the maintenance of the recording head is started. The ink jet recording apparatus according to claim 2 . A recording head provided with an ink ejection surface for ejecting ink by a first moving means when a jam detection means for detecting the occurrence of a jam in the recording medium detects the occurrence of a jam in the recording medium, and the ink ejection The recording head and the transport unit are moved apart relative to each other by moving the transport unit that transports the recording medium while facing the surface, and the recording medium transported by the transport unit by the second moving unit . The ejecting member disposed at a position facing the surface on the recording head side and the recording head are relatively moved so that the projecting member is moved from the recording head side toward the transport unit side from the ink ejection surface. a recording medium withdrawal method in the allowed Louis inkjet recording apparatus changes the projecting state,
The transport unit is disposed below the recording head;
The first moving means moves the transport unit up and down relative to the recording head,
The second moving means moves the ink ejection surface from the recording head side toward the transport unit side in conjunction with the separation operation of the recording head and the transport unit by the first moving means. A recording medium detaching method in an ink jet recording apparatus, wherein the recording medium is changed to a more protruding state and is a support portion provided in the transport unit and supporting the protruding member from below.