Liquid discharge head, liquid discharge device, and method for manufacturing a liquid discharge head

Abstract

The objective of this invention is to appropriately arrange the drive circuit. [Solution] A liquid discharge head 1 comprising a nozzle 14 for discharging liquid, a piezoelectric element 18, a drive IC 21 for driving the piezoelectric element 18, a base member 19 for holding the piezoelectric element 18, and an FPC cable 20 that holds the drive IC 21 inside and is attached to the side surface of the base member 19 on the inside and electrically connected to the piezoelectric element 18, wherein the side surface of the base member 19 has a stepped portion 19a that protrudes outward, and the portion of the FPC cable 20 that holds the drive IC 21 is positioned outside the side of the FPC cable 20 that holds the piezoelectric element 18.

Description

Technical Field

[0001] The present invention relates to a liquid ejection head, a liquid ejection device, and a method for manufacturing a liquid ejection head.

Background Art

[0002] There is a liquid ejection head provided with a piezoelectric element (pressure generating means) for generating pressure to pressurize the liquid in an individual liquid chamber, a base member (holding member) for holding the piezoelectric element, and an FPC cable (flexible wiring member) provided with a driver IC (driving circuit) for driving the piezoelectric element.

[0003] For example, as shown in FIG. 16, in the liquid ejection head of Patent Document 1 (Japanese Patent Application Laid-Open No. 2009-051068), a piezoelectric element 502 is fixed to a base member 501, and an FPC cable 503 is attached to the side surfaces of the base member 501 and the piezoelectric element 502. A driver IC 504 is attached to a portion of the FPC cable 503 that is not attached to the base member 501 and the piezoelectric element 502 inside.

[0004] In the configuration of Patent Document 1, the FPC cable 503 extends substantially linearly, and the positions where the driver IC 504 and the base member 501 are provided overlap in the left-right direction of FIG. 16. Therefore, as shown in FIGS. 17(a) and 17(b), when placing the actuator unit including the piezoelectric element 502 on a stage 505, which is a work placement table, in the manufacturing process of the liquid ejection head, there is a problem that the driver IC 504 interferes with the stage 505.

[0005] In particular, due to the difference in linear expansion between the base member 501 and the FPC cable 503, when the FPC cable 503 contracts due to temperature changes, the side of the FPC cable 503 that holds the driver IC 504 bends inward, making the driver IC 504 more likely to interfere with the stage 505. Such bending of the FPC cable 503 is likely to occur when the FPC cable 503 and the base member 501 are joined over a wide area in the nozzle arrangement direction. To counter this, the joining area between the FPC cable 503 and the base member 501 in the nozzle arrangement direction can be reduced, but this creates another problem: when an external force is applied to the FPC cable 503, excessive force is applied to the piezoelectric element 502, which can cause damage. [Overview of the project] [Problems that the invention aims to solve]

[0006] The objective of this invention is to appropriately arrange the drive circuit. [Means for solving the problem]

[0007] To solve the above problems, the present invention provides a liquid discharge head comprising: a nozzle for discharging liquid; a pressure generating means; a drive circuit for driving the pressure generating means; a holding member for holding the pressure generating means; and a flexible wiring member that holds the drive circuit inside and is attached to the side surface of the holding member on the inside and electrically connected to the pressure generating means, wherein the side surface of the holding member has a protruding portion that protrudes outward, and the portion of the flexible wiring member that holds the drive circuit is positioned outside the side of the flexible wiring member that holds the pressure generating means. [Effects of the Invention]

[0008] According to the present invention, the drive circuit can be appropriately arranged. [Brief explanation of the drawing]

[0009] [Figure 1]This is a cross-sectional view showing the area around the piezoelectric element of a liquid discharge head according to one embodiment of the present invention. [Figure 2] This diagram shows the individual piezoelectric elements of a piezoelectric element. [Figure 3] Figures (a) and (b) show the actuator unit of the embodiment being placed on the stage. [Figure 4] This diagram shows the process of applying adhesive to the piezoelectric element of an actuator unit fixed to a stage. [Figure 5] This diagram shows how the actuator unit is fixed to the workpiece. [Figure 6] This is a front view showing the actuator unit of the embodiment. [Figure 7] Figure 7 is a side view showing the actuator unit. [Figure 8] This is a front view showing an actuator unit different from that of the embodiment. [Figure 9] Figure 8 is a side view showing the actuator unit. [Figure 10] A side view showing an actuator unit of another embodiment. [Figure 11] This figure shows the actuator unit shown in Figure 10 being placed on the stage. [Figure 12] Figure 10 is a side view showing the actuator unit. [Figure 13] This is a front view of an inkjet recording apparatus equipped with a liquid ejection head according to the above embodiment of the present invention. [Figure 14] Figure 13 is a side view showing an overview of the mechanism of the inkjet recording device. [Figure 15] Figure 13 is a plan view of the main components of the mechanism of an inkjet recording device. [Figure 16] This is a cross-sectional view showing the area around the piezoelectric element of a conventional liquid dispensing head. [Figure 17] Figures (a) and (b) show the actuator unit provided on the liquid discharge head in Figure 16 being placed on the stage.

Best Mode for Carrying Out the Invention

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each figure, the same or corresponding parts are denoted by the same reference numerals, and redundant descriptions thereof will be simplified or omitted as appropriate.

[0011] FIG. 1 is a cross-sectional view showing the periphery of a piezoelectric element of a liquid ejection head according to an embodiment of the present invention, and is a view showing a cross-section perpendicular to the nozzle array direction.

[0012] As shown in FIG. 1, the liquid ejection head 1 includes a frame member 23, a diaphragm 12, a flow path substrate 11, and a nozzle plate 13 as a nozzle member, and these members are laminated and joined vertically. The flow path substrate 11 is formed of a SUS material. The nozzle plate 13 has a plurality of nozzles 14. Ink as a liquid is ejected from the nozzles 14.

[0013] The flow path substrate 11, the diaphragm 12, and the nozzle plate 13 are laminated and joined, and an individual liquid chamber 15, a fluid resistance portion 16, a buffer chamber 17, etc. are formed inside thereof. Ink is sent to the individual liquid chamber 15 through the fluid resistance portion 16 and ejected from the nozzles 14. The buffer chamber 17 suppresses pressure fluctuations in the common liquid chamber.

[0014] A frame member 23 is joined with an adhesive around the side of the diaphragm 12 opposite to the side joined to the flow path substrate 11. The frame member 23 forms a common liquid chamber 24 inside thereof. The common liquid chamber 24 communicates with the fluid resistance portion 16 and the individual liquid chamber 15 through a through hole 25 of the diaphragm 12.

[0015] The flow path substrate 11 is composed of a restrictor plate 11a and a chamber plate 11b that are adhered to each other. The flow path substrate 11 forms hole portions that constitute the individual liquid chambers 15, the fluid resistance portions 16, and the buffer chamber 17 by etching a SUS substrate using an acidic etching solution or by performing machining such as punching. The fluid resistance portion 16 is formed by forming a hole portion in the restrictor plate 11a and not forming a hole portion in the chamber plate 11b.

[0016] The diaphragm 12 is adhesively joined to the chamber plate 11b that constitutes the flow path substrate 11. This diaphragm 12 is formed by joining a convex portion 12b formed from a SUS substrate to a resin plate material 12a made of, for example, polyimide. In addition, for example, those formed from a nickel metal plate can also be used.

[0017] The nozzle plate 13 forms nozzles 14 with a diameter of 10 to 30 μm corresponding to the individual liquid chambers 15 and is adhesively joined to the restrictor plate 11a of the flow path substrate 11. As this nozzle plate 13, those made of metals such as stainless steel and nickel, resins such as polyimide resin films, silicon, and combinations thereof can be used. Further, on the nozzle surface (the surface in the discharge direction: the discharge surface), a water-repellent film is formed by a well-known method such as a plating film or a water-repellent agent coating in order to ensure water repellency with the ink.

[0018] The diaphragm 12 is adhesively joined to the chamber plate 11b that constitutes the flow path substrate 11. This diaphragm 12 is formed by joining a convex portion 12b formed from a SUS substrate to a resin plate material 12a made of, for example, polyimide. In addition, for example, those formed from a nickel metal plate can also be used.

[0019] The nozzle plate 13 forms nozzles 14 with a diameter of 10 to 30 μm corresponding to the individual liquid chambers 15 and is adhesively bonded to the restrictor plate 11a of the flow channel substrate 11. The nozzle plate 13 can be made of metals such as stainless steel and nickel, resins such as polyimide resin film, silicon, or combinations thereof. In addition, a water-repellent film is formed on the nozzle surface, which is the side from which the liquid is discharged, by a well-known method such as a plating film or a water-repellent coating to ensure water repellency with the ink.

[0020] Furthermore, the liquid discharge head 1 includes a piezoelectric element 18 as a pressure generating means, a base member 19 as a holding member, an FPC (Flexible Printed Circuit) cable 20 as a flexible wiring member, a driver IC 21 as a drive circuit, and a common electrode 32.

[0021] As shown in Figure 2, the laminated piezoelectric element 18 is divided into multiple sections on the individual liquid chamber 15 side by forming multiple grooves on the individual liquid chamber 15 side, thereby forming each piezoelectric element section 18a corresponding to each individual liquid chamber 15. As shown in Figure 1, the piezoelectric element 18 is joined to the diaphragm 12 on the side opposite to the individual liquid chamber 15. The portion of the piezoelectric element 18 opposite to the side joined to the diaphragm 12 is held by the base member 19.

[0022] The base member 19 is preferably made of a metal or ceramic material. If the base member 19 is made of a metal or ceramic material, heat accumulation due to self-heating of the piezoelectric element 18 can be suppressed. This suppresses a decrease in the bonding strength between the piezoelectric element 18 and the base member 19, and a deterioration of the spraying characteristics due to a decrease in ink viscosity.

[0023] The FPC cable 20 is joined to the electrode portion on the side of the piezoelectric element 18. The FPC cable 20 is bonded to the side of the base member 19 with adhesive 29. Multiple driver ICs 21 are mounted on the FPC cable 20. The driver ICs 21 are held on the inner surface of the FPC cable 20 and are located on the side opposite to the piezoelectric element 18 relative to the base member 19.

[0024] The driver IC 21 drives the piezoelectric elements 18 by applying a drive waveform (electrical signal) to each individual liquid chamber 15. By mounting multiple driver ICs 21 on the FPC cable 20 in this way, an electrical signal can be set for each driver IC 21, and variations in the displacement characteristics of each drive channel of the piezoelectric elements 18 can be easily corrected.

[0025] The FPC cable 20 is electrically connected to each piezoelectric element 18 via the base member 19 and the common electrode 32. Alternatively, the FPC cable 20 may be directly electrically connected to the piezoelectric elements 18.

[0026] By selectively applying a drive pulse voltage of 20 to 50 V to the piezoelectric element 18, the piezoelectric element 18 stretches in the stacking direction, deforming the diaphragm 12 toward the nozzle 14. As a result, the volume change in the individual liquid chambers 15 pressurizes the ink inside the individual liquid chambers 15, causing the ink to be ejected (sprayed) from the nozzle 14.

[0027] As the ink is ejected, the liquid pressure in the individual liquid chamber 15 decreases, and a slight negative pressure is generated within the individual liquid chamber 15 due to the inertia of the liquid flow. In this state, by turning off the voltage applied to the piezoelectric element 18, the diaphragm 12 returns to its original position and the individual liquid chamber 15 returns to its original shape, generating further negative pressure. At this time, ink is filled into the individual liquid chamber 15 via the common liquid chamber 24, the fluid resistance section 16, etc. Then, after the vibration of the ink meniscus surface of the nozzle 14 has dampened and stabilized, a pulse voltage is applied to the piezoelectric element 18 to eject the next ink droplet.

[0028] Although this explanation describes a method of ejecting ink by pushing, it is also possible to eject ink using a pull-pull method, where the potential is lowered from an intermediate potential applied to the piezoelectric element and then raised back to the intermediate potential, or a pull-push method, where the potential is lowered from an intermediate potential applied to the piezoelectric element and then raised to a potential higher than the intermediate potential. These methods can be set by the drive waveform.

[0029] Here, the base member 19 has a stepped portion 19a as a protruding part on its side surface. The stepped portion 19a is provided on the side of the base member 19 opposite to the piezoelectric element 18 side (the lower side in Figure 1) and is a part that protrudes outward from the side surface on the piezoelectric element 18 side (the upper side in Figure 1). This outward side refers to the outward side when the central side of the base member 19 is considered the inside and the sides of the base member 19 on both sides are considered the outside in the left-right direction of Figure 1. For example, on the left side surface of the base member 19 in Figure 1, the stepped portion 19a protrudes to the left of Figure 1 beyond the part where the stepped portion 19a is not provided. The left-right direction in Figure 1 is the short-side direction of the base member 19 and is also perpendicular to both the nozzle arrangement direction, which is perpendicular to the plane of the paper in Figure 1, and the direction parallel to the liquid discharge direction, which is the up-down direction in Figure 1. The stepped portion 19a forms a stepped shape between the base member 19 and the part of the side surface on the piezoelectric element 18 side.

[0030] The formation of the stepped portion 19a results in the FPC cable 20 having a shape where the stepped portion 19a side (lower side in Figure 1) extends outward in the short-side direction of the base member 19 more than the piezoelectric element 18 side (upper side in Figure 1). This allows the driver IC 21 held in the FPC cable 20 to be positioned further outward.

[0031] Figure 3 shows how the actuator unit 30 is attached to the stage 50, which serves as a mounting base. The actuator unit 30 includes a piezoelectric element 18, a base member 19, an FPC cable 20, a driver IC 21, and the like.

[0032] As shown in Figures 3(a) to 3(b), by providing a stepped portion 19a on the base member 19 and spreading the FPC cable 20 outwards, interference between the driver IC 21 and the stage 50 can be suppressed when the actuator unit 30 is placed on the stage 50. Therefore, it is possible to suppress the FPC cable 20 from peeling off the base member 19 or the driver IC 21 from being damaged due to contact between the driver IC 21 and the stage 50. Alternatively, the operation of spreading the FPC cable 20 outwards when placing the base member 19 on the stage 50 to prevent the driver IC 21 from interfering with the stage 50 becomes unnecessary, improving the workability of the process of placing the base member 19 on the stage 50 and preventing the FPC cable 20 from peeling off during the operation of spreading the FPC cable 20 outwards. Thus, in this embodiment, the driver IC 21 can be positioned in an appropriate location that does not interfere with the stage 50.

[0033] With the actuator unit 30 placed and fixed on the stage 50, subsequent processes for manufacturing the liquid discharge head are carried out. For example, as shown in Figure 4, a process of applying adhesive 29 to the piezoelectric element 18 can be carried out as a subsequent process. After that, as shown in Figure 5, the actuator unit 30 can be moved by grasping the stage 50 and attached to a workpiece 52 placed on another stage 51. However, the subsequent processes carried out with the actuator unit 30 (base member 19) placed and fixed on the stage 50 are not limited to these, and any appropriate process for manufacturing the liquid discharge head can be carried out.

[0034] Figure 6 is a front view showing the actuator unit, and Figure 7 is a side view. The left-right direction in Figure 6 and the perpendicular direction in Figure 7 represent the nozzle arrangement direction X. The nozzle arrangement direction X is also the longitudinal direction of the base member 19.

[0035] The range X1 shown in Figure 6 is the joining width in the nozzle arrangement direction where the base member 19 and the FPC cable 20 are joined by the adhesive 29. The range X2 is the joining width in the nozzle arrangement direction where the piezoelectric element 18 and the FPC cable 20 are joined.

[0036] In this embodiment, X1 is set to ≥ X2 × 0.8. This stabilizes the adhesion state of the FPC cable 20 to the base member 19, and suppresses the application of strong force to the joint portion of the piezoelectric element 18 with the FPC cable 20 when an external force is applied to the FPC cable 20.

[0037] Figure 8 is a front view showing an actuator unit 300 different from the embodiment described above, and Figure 9 is a side view thereof.

[0038] As shown in Figure 8, in the actuator unit 300 which differs from the above embodiment, the base member 190 and the FPC cable 200 are joined by adhesive 290 only at both ends in the arrangement direction X. If an external force is applied to the FPC cable 200 in the direction of the arrow in Figure 9 and it is pulled, the FPC cable 200 will deform significantly in the tensile direction because the joint area with the base member 190 is small. As a result, a large force is applied to the joint between the FPC cable 200 and the piezoelectric element 180, and there is a risk that the base of the piezoelectric element 180 will be damaged as shown in Figure 9. Therefore, as in the actuator unit 30 of this embodiment in Figure 7, by setting X1 ≥ X2 × 0.8 to provide a larger joint area between the FPC cable 20 and the base member 19, damage to the piezoelectric element 18 can be prevented. An example of when an external force is applied to the FPC cable in the direction of Figure 9 is when foreign matter attached to the FPC cable is removed with an adhesive stick.

[0039] Also, in the present embodiment, as shown in FIG. 7, the FPC cable 20 is joined to the base member 19 in a region where there is no step portion 19a on the side surface of the base member 19, i.e., in a region closer to the piezoelectric element 18 than the step portion 19a. And, setting the thickness as Y1 of the adhesive 29 that joins the base member 19 and the FPC cable 20, and setting the protrusion amount of the step portion 19a with respect to the other portion of the side surface of the base member 19 as Y2, it is set such that Y1 < Y2. That is, the outer end portion of the step portion 19a is provided on the outer side in the short side direction of the base member 19 than the outer end portion of the adhesive 29 that joins the base member 19 and the FPC cable 20. Thereby, as shown in FIG. 7, the FPC cable 20 can be more reliably spread outward from the piezoelectric element 18 side toward the driver IC 21 side. By spreading the driver IC 21 side of the FPC cable 20 outward, a force acting toward the piezoelectric element 18 side can be applied to the piezoelectric element 18 side (the upper side in FIG. 7) of the FPC cable 20 by the reaction force. That is, a force can be made to act in the direction in which the FPC cable 20 adheres to the base member 19. Thereby, even when an external force in the direction of separating the FPC cable 20 from the base member 19 as shown by the arrow direction in FIG. 7 is applied, the FPC cable 20 is less likely to separate from the piezoelectric element 18, and it can be prevented that an excessive force is applied to the piezoelectric element 18 and the piezoelectric element 18 is damaged.

[0040] Next, another example of the protrusion provided on the base member 19 will be described using FIG. 10.

[0041] As shown in FIG. 10, the base member 19 of the present embodiment includes a tapered surface 19b as a protrusion on its side surface. The tapered surface 19b is a surface that slopes outward in the short side direction of the base member 19 from the piezoelectric element 18 side toward the driver IC 21 side. In other words, due to the tapered surface 19b, the driver IC 21 side (the lower side in the figure) protrudes outward in the short side direction of the base member 19 more than the piezoelectric element 18 side (the upper side in FIG. 10). Due to this tapered surface 19b, the driver IC 21 side (the lower side in FIG. 10) of the base member 19 spreads outward, and the FPC cable 20 joined to the base member 19 also spreads outward on the side that holds the driver IC 21.

[0042] In this embodiment as well, as shown in Figure 11, the side of the FPC cable 20 that holds the driver IC 21 expands outward, allowing the driver IC 21 to be positioned appropriately. This suppresses interference between the driver IC 21 and the stage 50 when the actuator unit 30 is placed on the stage 50.

[0043] In this embodiment, the tapered surface 19b reduces the pressure applied to the FPC cable 20 when it is pushed from the outside, compared to when the corner of the stepped portion 19a (see Figure 7) in the previous embodiment comes into contact with it. Therefore, damage to the FPC cable 20 can be prevented. However, damage to the FPC cable 20 can also be suppressed by chamfering the corner of the stepped portion 19a. Furthermore, compared to the stepped portion 19a, the FPC cable 20 can be spread outward more closely to the tapered surface 19b, making it easier to adjust the inclination of the FPC cable 20.

[0044] In this embodiment as well, similar to Figure 6 of the previously described embodiment, it is preferable to set X1 ≥ X2 × 0.8 in the nozzle arrangement direction range X1 where the base member 19 and the FPC cable 20 are joined, and in the nozzle arrangement direction range X2 where the base member 19 and the piezoelectric element 18 are joined. This suppresses the application of strong force to the bonding portion of the piezoelectric element 18 with the FPC cable 20, thereby preventing damage to the piezoelectric element 18.

[0045] Furthermore, in the above embodiment, as shown in Figure 12, the edge B1 on the driver IC side (lower side in Figure 12) of the tapered surface 19b is positioned outside the base member 19 (left side in Figure 12) of the end B2 on the base member 19 side of the adhesive 29 that bonds the base member 19 and the FPC cable 20. This allows the driver IC side of the FPC cable 20 to be spread outward from the piezoelectric element 18 side, and the reaction force applies a force toward the base member 19 side to the piezoelectric element 18 side of the FPC cable 20. This prevents damage to the piezoelectric element 18, similar to the previously described embodiment.

[0046] Next, an image forming apparatus as a liquid ejection device equipped with a liquid ejection head according to one embodiment of the present invention will be described with reference to Figures 13 to 15. This image forming apparatus is an inkjet recording apparatus. Figure 13 is a perspective view of the inkjet recording apparatus viewed from the front, Figure 14 is a side view showing an overview of the mechanism of the inkjet recording apparatus, and Figure 15 is a plan view of the main part of the mechanism of the inkjet recording apparatus.

[0047] The inkjet recording device 100 shown in Figure 13 comprises a main unit 101, a paper feed tray 102, and a paper output tray 103. The paper feed tray 102 loads paper that is mounted on the main unit 101. The paper output tray 103 is detachably attached to the main unit 101 and stores paper on which images have been recorded (formed). A cartridge loading section 104 is provided on one end of the front of the main unit 101 (to the side of the paper feed and output tray section). The cartridge loading section 104 protrudes forward from the main unit 101 and is used to load ink cartridges. An operation / display section 105, which has operation buttons and a display, is provided on the upper surface of the cartridge loading section 104.

[0048] The cartridge loading section 104 allows for the insertion of multiple ink cartridges, namely ink cartridges 110k, 110c, 110m, and 110y (referred to as "ink cartridge 110" when the colors are not distinguished), from the front to the rear of the main body 101. Each ink cartridge 110 contains a different color of ink; for example, black (K), cyan (C), magenta (M), and yellow (Y) inks. A front cover (cartridge cover) 106 is provided on the front side of the cartridge loading section 104, which can be opened and closed. The front cover 106 is opened when inserting or removing the ink cartridges 110. The ink cartridges 110k, 110c, 110m, and 110y are loaded in a vertical position, arranged horizontally.

[0049] Furthermore, the operation / display unit 105 is equipped with ink level indicators 111k, 111c, 111m, and 111y for each color. These indicators are positioned to correspond to the installation locations of the respective ink cartridges 110k, 110c, 110m, and 110y, and indicate when the ink level of each cartridge reaches the near end or end. Additionally, the operation / display unit 105 is equipped with a power button 112, a paper feed / print resume button 113, and a cancel button 114.

[0050] Furthermore, the main body of the device 101 is equipped with a frame 121. A guide rod 131, which serves as a guide member, is horizontally mounted between the left and right side plates 121A and 121B that constitute the frame 121. The carriage 133 is slidably held by the guide rod 131 and a stay 132 in the direction of the main scanning direction, which is the direction of the double arrows in Figure 15. The carriage 133 moves and scans along the guide rod 131 in the direction of the arrows in Figure 15 (carriage main scanning direction) as the driving force of the main scanning motor is transmitted via a timing belt.

[0051] The carriage 133 holds four liquid ejection heads 1, each ejecting ink droplets of yellow (Y), cyan (C), magenta (M), and black (Bk). Each liquid ejection head 1, while held in the carriage 133, has multiple ink ejection ports arranged in a direction intersecting the main scanning direction, with the downstream side of each ink ejection port facing downwards.

[0052] The driver IC of the liquid ejection head 1 is connected to the control unit via an FPC cable 20. The carriage 133 is equipped with sub-tanks 135 for each color to supply ink of each color to the liquid ejection head 1. Ink of each color is supplied to these sub-tanks 135 from ink cartridges 110 of each color installed in the cartridge loading unit 104 via ink supply tubes 136 of each color. The cartridge loading unit 104 is equipped with a supply pump unit 124 for transporting the ink from the ink cartridges 110, and the ink supply tubes 136 are held in place by a locking member 125 on the rear plate 121C that constitutes the frame 121 along their route.

[0053] On the other hand, the paper feed tray 102 is equipped with a crescent-shaped roller (paper feed roller) 143 and a separation pad 144 facing the paper feed roller 143. The crescent-shaped roller 143 separates and feeds the paper 142 one sheet at a time from the paper stacking section 141. The separation pad 144 faces the paper feed roller 143 and is biased toward the paper feed roller 143. The separation pad 144 is made of a material with a high coefficient of friction. The paper feed roller 143 and the separation pad 144 separate the paper 142 one sheet at a time from the stack of paper 142 stacked on the paper stacking section (pressure plate) 141 and feed it downstream.

[0054] The inkjet recording device 100 includes a guide member 145 for guiding the paper 142, a counter roller 146, a transport guide member 147, a pressing member 148 having a front pressure roller 149, and a transport belt 151. The guide member 145, the counter roller 146, the transport guide member 147, and the pressing member 148 feed the paper 142 fed from the paper tray 102 to the lower side of the liquid ejection head 1. The transport belt 151 electrostatically attracts the paper 142 and transports it to a position facing the liquid ejection head 1.

[0055] The conveyor belt 151 is an endless belt, stretched between the conveyor roller 152 and the tension roller 153, and configured to circulate in the belt conveying direction (sub-scanning direction). A charging roller 156 is also provided, which is a means for charging the surface of the conveyor belt 151. This charging roller 156 contacts the surface of the conveyor belt 151 and rotates in accordance with the rotation of the conveyor belt 151. Furthermore, a guide member 157 is positioned on the back side of the conveyor belt 151, corresponding to the printing area by the liquid discharge head 1.

[0056] The conveyor belt 151 moves in a circular motion in the belt conveying direction as the conveyor rollers 152 are rotated by a sub-scanning motor.

[0057] Furthermore, the paper discharge section for discharging the paper 142 recorded by the liquid discharge head 1 includes a separation claw 161, a paper discharge roller 162, a paper discharge roller 163, and a paper discharge tray 103 located below the paper discharge roller 162. The separation claw 161 separates the paper 142 from the transport belt 151.

[0058] Furthermore, a duplex unit 171 is detachably attached to the rear of the main unit 101. The duplex unit 171 takes in the paper 142 that is returned by the reverse rotation of the transport belt 151, flips it over, and feeds it again between the counter roller 146 and the transport belt 151. The top surface of the duplex unit 171 also forms a manual feed tray 172.

[0059] Furthermore, as shown in Figure 15, a maintenance and recovery mechanism 181, which includes a recovery means for maintaining and restoring the state of the nozzle of the liquid ejection head 1, is positioned in the non-printing area on one side of the scanning direction of the carriage 133.

[0060] This maintenance and recovery mechanism 181 includes cap members (hereinafter referred to as "caps") 182a to 182d (hereinafter referred to as "caps 182" when not distinguished), a wiper blade 183, and an empty discharge receiver 184. The caps 182 cap each nozzle surface of the liquid discharge head 1. The wiper blade 183 is a blade member for wiping the nozzle surface. The empty discharge receiver 184 receives the empty discharged ink. Empty discharge is an operation that discharges ink droplets that do not contribute to recording in order to discharge the thickened ink. Here, cap 182a is used as a suction and moisturizing cap, and the other caps 182b to 182d are used as moisturizing caps.

[0061] Then, the waste ink generated by the maintenance and recovery operation of the maintenance and recovery mechanism 181, the ink discharged into the cap 182, the ink adhering to the wiper blade 183 and removed by the wiper cleaner 185, and the ink discharged into the empty discharge receiver 194 are discharged into the waste liquid tank and stored therein.

[0062] Furthermore, as shown in Figure 15, an empty ejection receiver 188 is placed in the non-printing area on the other side of the scanning direction of the carriage 133, and this empty ejection receiver 188 is equipped with an opening 189 that is aligned with the nozzle row direction of the liquid ejection head 1.

[0063] In the inkjet recording device 100 configured in this way, sheets of paper 142 are fed one by one from the paper feed tray 102. The paper 142 fed approximately vertically upward is guided by the guide member 145, and is transported between the transport belt 151 and the counter roller 146. Its leading edge is then guided by the transport guide member 147 and pressed against the transport belt 151 by the leading pressure roller 149, thereby changing the transport direction by approximately 90°.

[0064] At this time, the AC bias supply unit of the control unit applies an alternating voltage to the charging roller 156 such that positive and negative outputs alternately occur. The charging roller 156 causes the transport belt 151 to be alternately charged with positive and negative charges in a predetermined width strip in the circumferential direction, i.e., the sub-scanning direction. When paper 142 is fed onto this alternately charged transport belt 151, the paper 142 is attracted to the transport belt 151, and the circumferential movement of the transport belt 151 causes the paper 142 to be transported in the sub-scanning direction.

[0065] Therefore, based on the main scanning position information from the linear encoder 137, the carriage 133 is moved in the main scanning direction, and the liquid ejection head 1 is driven according to the image signal to eject ink droplets onto the stationary paper 142 to record one line. After transporting a predetermined amount of paper 142, the next line is recorded. Upon receiving a recording completion signal or a signal that the rear end of the paper 142 has reached the recording area, the recording operation is terminated and the paper 142 is ejected into the output tray 103.

[0066] Furthermore, while waiting to print (record), the carriage 133 is moved to the maintenance and recovery mechanism 181, and the liquid ejection head 1 is capped by the cap 182, keeping the nozzle moist and preventing ejection failure due to ink drying. Also, with the liquid ejection head 1 capped by the cap 182, a recovery operation is performed in which ink is sucked from the nozzle by a suction pump, and viscous ink and air bubbles are discharged. In addition, a dry ejection operation is performed before recording starts and during recording. This maintains the stable ejection performance of the liquid ejection head 1.

[0067] Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the present invention.

[0068] The shape of the protrusion provided on the holding member is not limited to the shape of the embodiment described above. Any suitable shape can be adopted as long as the protrusion causes the drive circuit side of the flexible wiring member to extend outward more than the piezoelectric element side.

[0069] In this application, the discharged liquid is not particularly limited as long as it has a viscosity and surface tension that can be discharged from the head, but it is preferable that its viscosity becomes 30 mPa·s or less at room temperature and atmospheric pressure, or when heated or cooled. More specifically, it is a solution, suspension, emulsion, etc. containing a solvent such as water or an organic solvent, a colorant such as a dye or pigment, a polymerizable compound, a resin, a functional material such as a surfactant, a biocompatible material such as DNA, amino acids or proteins, calcium, or an edible material such as a natural pigment. These can be used, for example, as inkjet inks, surface treatment liquids, liquids for forming components of electronic elements and light-emitting elements or electronic circuit resist patterns, and three-dimensional molding material liquids.

[0070] The term "liquid" includes not only ink but also paints, pre-treatment solutions, binders, and overcoat solutions.

[0071] The pressure generating means of the present invention includes those that use piezoelectric actuators (multilayer piezoelectric elements and thin-film piezoelectric elements), thermal actuators that use electrothermal conversion elements such as heating resistors, and electrostatic actuators consisting of a diaphragm and a counter electrode.

[0072] A "liquid discharge unit" is a liquid discharge head with integrated functional components and mechanisms, and includes an assembly of parts related to liquid discharge. For example, a "liquid discharge unit" may include a combination of a liquid discharge head with at least one of the following components: a head tank, carriage, supply mechanism, maintenance and recovery mechanism, main scanning movement mechanism, and liquid circulation device.

[0073] Here, integration includes, for example, cases where the liquid dispensing head and functional components or mechanisms are fixed to each other by fastening, bonding, engaging, etc., or where one is held movably relative to the other. Furthermore, the liquid dispensing head and functional components or mechanisms may be configured to be detachable from each other.

[0074] For example, some liquid dispensing units have a liquid dispensing head and head tank integrated into one unit. Others have a liquid dispensing head and head tank integrated into one unit, connected to each other by tubes or similar means. In these liquid dispensing units, a unit including a filter can also be added between the head tank and the liquid dispensing head.

[0075] Additionally, some liquid dispensing units have an integrated liquid dispensing head and carriage.

[0076] Furthermore, some liquid dispensing units integrate the liquid dispensing head and the scanning mechanism by movably holding the liquid dispensing head in a guide member that constitutes part of the scanning mechanism. Others integrate the liquid dispensing head, carriage, and main scanning mechanism.

[0077] Furthermore, some liquid dispensing units integrate the liquid dispensing head, carriage, and maintenance / recovery mechanism by fixing a cap component, which is part of the maintenance / recovery mechanism, to a carriage to which the liquid dispensing head is attached.

[0078] Furthermore, some liquid discharge units have a head tank or a liquid discharge head to which flow path components are attached, to which a tube is connected, integrating the liquid discharge head and the supply mechanism. Through this tube, the liquid from the liquid storage source is supplied to the liquid discharge head.

[0079] The main scanning movement mechanism shall include the guide member alone. The supply mechanism shall also include the tube alone and the loading section alone.

[0080] Here, the "liquid dispensing unit" is described in combination with a liquid dispensing head, but the "liquid dispensing unit" also includes a head module or head unit that includes the liquid dispensing head mentioned above, as well as the functional components and mechanisms described above, all integrated together.

[0081] A "liquid dispensing device" includes devices that drive a liquid dispensing head to dispense liquid, such as a liquid dispensing head, liquid dispensing unit, head module, and head unit. Liquid dispensing devices include not only devices that can dispense liquid onto surfaces to which liquid can adhere, but also devices that dispense liquid into air or into liquid.

[0082] This "liquid dispensing device" may also include means for feeding, transporting, and dispensing paper onto materials to which liquid can adhere, as well as pre-treatment devices, post-treatment devices, etc.

[0083] For example, "liquid ejection devices" include image forming devices that eject ink to form images on paper, and three-dimensional molding devices that eject molding liquid into a powder layer formed in layers to create three-dimensional objects.

[0084] Furthermore, the term "liquid dispensing device" is not limited to those that visualize meaningful images such as letters or figures through the dispensed liquid. For example, it also includes devices that form patterns that do not have meaning in themselves, or devices that create three-dimensional images.

[0085] The term "material to which liquid can adhere" above refers to a material to which liquid can adhere at least temporarily, such as material to which liquid adheres and solidifies, or material to which liquid adheres and penetrates, and is the recording medium in the above embodiment. Specific examples include recording media such as paper, recording paper, film, and cloth; electronic components such as electronic circuit boards and piezoelectric elements; powder layers; organ models; and inspection cells. Unless otherwise specified, it includes all materials to which liquid can adhere.

[0086] The materials referred to as "materials to which liquid can adhere" above include paper, thread, fibers, fabrics, leather, metal, plastic, glass, wood, ceramics, etc., as long as liquid can adhere to them, even temporarily.

[0087] Other examples of "liquid dispensing devices" include processing liquid coating devices that dispense processing liquid onto the surface of paper for purposes such as modifying the paper surface, and injection granulation devices that granulate fine particles of raw materials by spraying a compositional liquid, in which raw materials are dispersed in a solution, through a nozzle.

[0088] In this application, the terms image formation, recording, printing, copying, printing, and shaping are all considered synonymous.

[0089] Examples of the present invention are as follows: <1> A nozzle for dispensing liquid, Pressure generating means and A drive circuit for driving the pressure generating means, A holding member that holds the pressure generating means, A liquid discharge head comprising: a flexible wiring member that holds the drive circuit inside and is attached to the side of the holding member inside and electrically connected to the pressure generating means, The liquid discharge head is characterized in that the side surface of the holding member has a protruding portion that projects outward, and the portion that holds the drive circuit of the flexible wiring member by the protruding portion is positioned outward from the pressure generating means side of the flexible wiring member. <2> The flexible wiring member, the holding member, and the pressure generating means are joined together. The joining width between the holding member and the flexible wiring member in the nozzle arrangement direction is 80% or more of the joining width between the pressure generating means and the flexible wiring member in the nozzle arrangement direction. <1> This is the liquid dispensing head described. <3> The protruding portion forms a stepped shape relative to the side of the holding member that is on the side of the pressure generating means. <1> or <2> This is the liquid dispensing head described. <4> The flexible wiring member is bonded with adhesive to the portion of the side surface of the holding member other than the protruding portion, on the side closer to the pressure generating means than the protruding portion. The aforementioned protrusion is positioned outside the adhesive that bonds the holding member and the flexible wiring member. <3> This is the liquid dispensing head described. <5> The protruding portion is a tapered surface that slopes outward from the pressure generating means side toward the drive circuit side. <1> or <2> This is the liquid dispensing head described. <6> The flexible wiring member is bonded to the side surface of the holding member with adhesive. The end of the tapered surface of the retaining member on the drive circuit side is positioned outside the adhesive. <5> This is the liquid dispensing head described. <7> <1> from <6> This is a liquid dispensing device equipped with one of the liquid dispensing heads described above. <8> A nozzle for dispensing liquid, Pressure generating means and A drive circuit for driving the pressure generating means, A holding member that holds the pressure generating means, A method for manufacturing a liquid discharge head, comprising a flexible wiring member that holds the drive circuit inside and whose inner surface is attached to the side surface of the holding member and electrically connected to the pressure generating means, With the flexible wiring member having the drive circuit attached to the holding member, the step of placing the side of the holding member opposite to the pressure generating means side on a mounting table for performing a subsequent process is provided. The retaining member has a protruding portion on its side that extends outward, The method for manufacturing a liquid discharge head is characterized in that, when the holding member is placed on the stand described above, the portion of the flexible wiring member that holds the drive circuit by the protrusion is positioned outside the pressure generating means side of the flexible wiring member. [Explanation of Symbols]

[0090] 1. Liquid dispensing head 14 nozzles 18. Piezoelectric element (pressure generating means) 19. Base member (holding member) 19a Stepped section (protruding section) 19b Tapered surface (protruding part) 20 FPC (Flexible Printed Circuit) 21. Driver IC (Driver Circuit) 29 Adhesives 30 Actuator Units 50 stages (mounting platforms) 100 Inkjet recording device (liquid ejection device) X Nozzle alignment direction X1 Joint width between base member and FPC cable in the nozzle arrangement direction X2 Bonding width between piezoelectric element and FPC cable in the nozzle arrangement direction [Prior art documents] [Patent Documents]

[0091] [Patent Document 1] Japanese Patent Publication No. 2009-051068

Claims

1. A nozzle for dispensing liquid, Pressure generating means and A drive circuit for driving the pressure generating means, A holding member that holds the pressure generating means, A liquid discharge head comprising: a flexible wiring member that holds the drive circuit inside and is attached to the side of the holding member inside and electrically connected to the pressure generating means, A liquid discharge head characterized in that the side surface of the holding member has a protruding portion that projects outward, and the portion of the flexible wiring member that holds the drive circuit by the protruding portion is positioned outward from the side of the flexible wiring member that holds the drive circuit.

2. The flexible wiring member, the holding member, and the pressure generating means are joined together. The liquid discharge head according to claim 1, wherein the joining width between the holding member and the flexible wiring member in the nozzle arrangement direction is 80% or more of the joining width between the pressure generating means and the flexible wiring member in the nozzle arrangement direction.

3. The liquid discharge head according to claim 1, wherein the protruding portion forms a stepped shape relative to the side surface of the holding member on the side of the pressure generating means.

4. The flexible wiring member is bonded with adhesive to the portion of the side surface of the holding member other than the protruding portion, on the side closer to the pressure generating means than the protruding portion. The liquid dispensing head according to claim 3, wherein the protruding portion is positioned outside the adhesive that bonds the holding member and the flexible wiring member.

5. The liquid discharge head according to claim 1, wherein the protruding portion is a tapered surface that is inclined outward from the pressure generating means side toward the drive circuit side.

6. The flexible wiring member is bonded to the side surface of the holding member with adhesive. The liquid dispensing head according to claim 5, wherein the end of the tapered surface of the holding member on the drive circuit side is positioned outside the adhesive.

7. A liquid dispensing device comprising a liquid dispensing head according to any one of claims 1 to 6.

8. A nozzle for dispensing liquid, Pressure generating means and A drive circuit for driving the pressure generating means, A holding member that holds the pressure generating means, A method for manufacturing a liquid discharge head, comprising a flexible wiring member that holds the drive circuit inside and whose inner surface is attached to the side surface of the holding member and electrically connected to the pressure generating means, With the flexible wiring member having the drive circuit attached to the holding member, the step of placing the side of the holding member opposite to the pressure generating means side on a mounting table for performing a subsequent process is provided. The retaining member has a protruding portion on its side that extends outward, A method for manufacturing a liquid discharge head, characterized in that, when the holding member is placed on the stand described above, the portion of the holding member that holds the drive circuit of the flexible wiring member by the protrusion is positioned outside the pressure generating means side of the flexible wiring member.

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