JP2021160139A - Head module, and printer provided with the same - Google Patents

Abstract

To provide a head module capable of making the temperature of the liquid uniform so as to inhibit deterioration of image quality.SOLUTION: In a head unit 110, air supplied from an air pump through a tube 271 hits an air guide 350 so as to flow toward inflow holes 341a and 341b. The air flowing through the inflow holes 341a and 341b flows downward passing through a gap between a surface (upper surface), on a side opposite to a surface (lower surface) provided with a terminal (not shown), of a base portion 241B of a COF 241, and a COF retainer 340. Thereby, the air can flow on the upper surface of the base portion 241B of the COF 241.SELECTED DRAWING: Figure 11

Description

The present invention relates to a head module used in a printing device and a printing device including the head module.

Conventionally, a plate-shaped actuator having a plurality of individual electrodes, a flow path member joined to the actuator and having a plurality of pressure chambers, and a heating member of the actuator arranged on a surface opposite to the flow path member. (For example, Patent Document 1). The heating member includes a protrusion that directly or indirectly contacts the plate-shaped actuator. The protrusions are arranged between the plurality of individual electrodes and the outer edge of the actuator.

Since the peripheral portion of the flow path member is close to the outside air, it is easier to be cooled than the central portion. In the inkjet printer, the convex portion is arranged between the plurality of individual electrodes and the outer edge of the actuator. As a result, a large amount of heat is supplied to the outer edge portion of the actuator, which is easily cooled, and heat is transferred from there to the central portion of the flow path member. Therefore, the temperature of the flow path member can be made uniform, the temperature unevenness of the ink in the flow path member can be reduced, and the temperature of the ink can be made uniform. As a result, deterioration of image quality can be suppressed.

Japanese Unexamined Patent Publication No. 2018-171856

Since the viscosity of the ink changes depending on the temperature, it is required to maintain the temperature of the ink at a predetermined appropriate temperature in order to keep the viscosity of the ink in a state suitable for printing. However, if the actuator is continuously driven for a long time, such as by performing high-speed printing, the temperature of the actuator rises, and the temperature of the ink in the flow path member may rise above the appropriate temperature accordingly. be. The liquid ejection device described in Patent Document 1 has a structure aimed at warming a portion (low temperature portion) of the flow path member that is easily cooled in order to reduce temperature unevenness of the ink in the flow path member. .. Therefore, when the temperature of the ink in the flow path member rises above an appropriate temperature as the temperature of the actuator rises, it cannot be cooled.

The present invention has been made in view of such circumstances, and even when the temperature of the liquid rises as the temperature of the actuator rises, the temperature of the liquid can be made uniform and the deterioration of image quality can be suppressed. The purpose is to provide the means by which it can be done.

The liquid discharge device according to the present disclosure includes a plurality of pressure chambers, a flow path member in which a manifold communicating with the plurality of pressure chambers is formed, and a plurality of actuators having a plurality of individual electrodes corresponding to the plurality of pressure chambers. With a head that has,
A flexible cable arranged so as to overlap the plurality of actuators in the stacking direction, and having a first portion having a plurality of terminals connected to the plurality of individual electrodes formed on the first surface thereof. ,
A flexible cable fixing member in which an inflow hole and an exhaust hole are formed and arranged so as to face the second surface of the flexible cable, which is the back surface of the first surface.
A guide member configured to guide the flow of air toward the inflow hole of the flexible cable fixing member is provided.

According to the above configuration, the guide member can guide the air flow toward the inflow hole of the flexible cable fixing member. Since the flexible cable fixing member is arranged so as to face the flexible cable, the air flowing through the inflow hole can flow between the flexible cable and the flexible cable fixing member. As a result, the flexible cable can be air-cooled. Along with this, the plurality of actuators connected to the flexible cable can be cooled to reduce the variation in the temperature of the liquid in the pressure chamber.

A second portion of the second surface of the flexible cable that overlaps with the first portion may form a part of an air flow path connecting the inflow hole and the outflow hole of the flexible cable fixing member. ..

In this case, the air flow is guided toward the inflow hole of the flexible cable fixing member by the guide member, so that the air is directly applied to the second portion of the second surface of the flexible cable, which overlaps with the first portion. Because it can be air-cooled efficiently.

The inflow hole may be arranged at a position overlapping the second portion of the flexible cable in the stacking direction.

In this case, since the air flowing into the inflow hole can flow toward the second portion of the flexible cable before it is warmed up, the vicinity of the second portion of the flexible cable can be efficiently air-cooled.

The guide member may have a guide port, and the guide port of the guide member may be located at a position overlapping the inflow hole in the stacking direction.

In this case, the air flowing toward the guide port can be efficiently guided toward the inflow hole.

The guide port may include an inlet, an outlet closer to the inflow hole than the inlet, and an intermediate portion located between the inlet and the outlet in the stacking direction, and the intermediate portion may include the intermediate portion. An air flow adjusting member may be provided to guide the air flowing in the stacking direction from the inlet in a direction different from the stacking direction. In this case, for example, the intermediate portion of the guide port can be formed as a slope inclined from the inlet to the outlet in a direction different from the stacking direction. As a result, it is possible to easily guide the air to change the direction of flow. The orthogonal cross-sectional area of the inlet of the guide port, which is the area of the cross section orthogonal to the stacking direction, may be smaller than the orthogonal cross-sectional area of the outlet and the orthogonal cross-sectional area of the intermediate portion. The orthogonal cross-sectional area of the intermediate portion of the guide port may be smaller than the orthogonal cross-sectional area of the outlet.

The outflow hole may be opened on the upper surface of the flexible cable fixing member in the stacking direction.

In this case, the warmed and lightened air between the flexible cable fixing member and the flexible cable can be efficiently discharged upward through the outflow hole.

The surface of the flexible cable fixing member facing the second surface of the flexible cable is located between the abutting portion of the flexible cable in contact with the second surface and the second surface of the flexible cable. It may include a separation portion forming a gap.

In this case, an air flow path can be easily secured between the flexible cable fixing member and the flexible cable.

The separated portion of the flexible cable fixing member is formed between a first separated portion forming a first gap with the second surface of the flexible cable and the second surface of the flexible cable. It may have a second separated portion that forms a second gap that is larger than the first gap.

In this case, the resistance of the air flow path can be reduced between the flexible cable fixing member and the flexible cable, and air can flow efficiently.

It is a top view which shows the printer 1. It is a top view which shows the inkjet head 4 substantially. It is a top view which shows the head 50. It is a perspective view of the head unit 11. It is an exploded perspective view of the head unit 11. It is an exploded perspective view of the wiring part 40. It is explanatory drawing for demonstrating the flow of air in a head unit 11. It is an exploded perspective view of the wiring part 30. It is explanatory drawing for demonstrating the state in which the COF presser 340 and the air guide 350 are overlapped. It is explanatory drawing for demonstrating the back surface of the COF presser 340 and the air guide 350. It is explanatory drawing for demonstrating the flow of air in a head unit 110.

<First Embodiment>
This will be described with reference to the drawings showing the printer 1 according to the first embodiment. FIG. 1 is a plan view illustrating the printer 1. In FIG. 1, the transport direction of the recording paper 100 (recording medium) corresponds to the front-back direction of the printer 1. The width direction of the recording paper 100 corresponds to the left-right direction of the printer 1. Further, the directions orthogonal to the front-rear direction and the left-right direction, that is, the vertical direction on the paper surface of FIG. 1, correspond to the vertical direction (corresponding to the stacking direction) of the printer 1.

<Configuration of printer 1>
As shown in FIG. 1, the printer 1 mainly includes a platen 3 housed in a housing 2, four head bars 4, two transport rollers 5, 6, and a controller 7.

The recording paper 100 is placed on the upper surface of the platen 3. The four head bars 4 are arranged in the transport direction above the platen 3. Each head bar 4 is a so-called line type head. Ink is supplied to the head bar 4 from an ink tank (not shown). Inks of different colors are supplied to the four head bars 4.

As shown in FIG. 1, the two transport rollers 5 and 6 are arranged rearward and anterior to the platen 3, respectively. The two transfer rollers 5 and 6 are driven by the motors M, respectively, and transfer the recording paper 100 on the platen 3 forward.

The controller 7 includes an FPGA (Field Programmable Gate Array), an EEPROM (Electrically Erasable Programmable Read-Only Memory), a RAM (Random Access Memory), and the like. The controller 7 may include a CPU (Central Processing Unit), an ASIC (Application Specific Integrated Circuit), or the like. The controller 7 is connected to an external device 9 such as a PC so as to be capable of data communication, and controls each part of the printer 1 based on the print data sent from the external device 9.

As shown in FIG. 2, the head bar 4 includes a plurality of head units 11. The plurality of head units 11 are attached to the holding plate 10 in a staggered manner. The head unit 11 has a plurality of nozzles 56 arranged in the left-right direction. Note that FIG. 2 is a schematic diagram, and the number of rows of nozzles in FIG. 2 and the number of rows of nozzles in FIG. 3 are different.

The controller 7 controls the motor M (see FIG. 1) that drives the transfer rollers 5 and 6 to transfer the recording paper 100 to the two transfer rollers 5 and 6 in the transfer direction. Further, the controller 7 controls four head bars 4 to eject ink from the nozzle 30d toward the recording paper 100. As a result, the image is printed on the recording paper 100.

<Structure of head unit 11>
As shown in FIGS. 4 and 5, the head unit 11 includes a frame 20, a wiring portion 40, a head 50, and a cover 60. As will be described later, the head 50 includes an actuator unit 51 (see FIG. 3) and a flow path member 55 (see FIG. 3), and the cover 60 includes a first cover 61 and a second cover 62.

<Frame 20>
As shown in FIG. 5, the frame 20 has an alignment frame 210, a back-end frame 220, and a front-end frame 230 that are arranged so as to be stacked in the vertical direction. Alignment holes 214 for positioning are formed at both ends of the alignment frame 210 in the left-right direction. The alignment frame 210 is fixed to the holding plate 10 (see FIG. 2) by being screwed to the holding plate 10 via the alignment hole 214. A back-end frame 220 is arranged below the alignment frame 210, and a front-end frame 230 is further below the alignment frame 210.

As shown in FIG. 5, a substantially rectangular opening 211 is formed in the substantially center of the alignment frame 210. On the right side of the opening 211 of the alignment frame 210, four through holes 212 that penetrate the alignment frame 210 in the vertical direction are formed. The four through holes 212 are arranged in a row in the front-rear direction. Although not shown in FIG. 5, as shown in FIG. 4, tube connectors T for connecting tubes are attached to each of the four through holes 212. Further, three intake holes 213 that penetrate the alignment frame 210 in the vertical direction are formed between the front end portion of the alignment frame 210 and the opening 211 in the front-rear direction. The three intake holes 213 are arranged in a row in the left-right direction. Although not shown in FIG. 5, the first cover 61 is arranged above the alignment frame 210 as shown in FIG. A rectangular opening is formed substantially in the center of the first cover 61, and the second cover 62 is exposed from the opening. Further, four through holes are provided at the right end of the first cover 61 corresponding to the tube connector T. A long notch 61C in the left-right direction is formed at a position behind the first cover 61 so as to overlap the opening 211 in the up-down direction. As a result, a slit SL1 penetrating in the vertical direction is formed between the first cover 61 and the alignment frame 210.

A recess 221 having a substantially rectangular opening is formed in the substantially center of the back end frame 220. On the right side of the recess 221 of the back-end frame 220, four flow paths 222 that penetrate the back-end frame 220 in the vertical direction are formed. The four flow paths 222 are arranged in a row in the front-rear direction. Further, three intake holes 223 penetrating the back end frame 220 in the vertical direction are formed between the front end portion of the back end frame 220 and the recess 221 in the front-rear direction. The three intake holes 223 are arranged in a row in the left-right direction. A second cover 62 is arranged above the recess 221 of the back end frame 220. A slit SL2 long in the left-right direction is formed between the rear end of the back end frame 220 and the recess 221.

A substantially rectangular opening 231 is formed in the substantially center of the front end frame 230. On the right side of the opening 231 of the front end frame 230, four flow paths 232 that penetrate the front end frame 230 in the vertical direction are formed. The four flow paths 232 are arranged in a row in the front-rear direction. Further, a slope 233 (an example of an intermediate portion of the intake channel) is provided between the front end portion of the front end frame 230 and the opening 231 in the front-rear direction. The slope 233 is an inclined surface that is inclined so as to be inclined downward toward the rear.

The alignment frame 210, the back end frame 220, and the front end frame 230 are laminated in the vertical direction (corresponding to the stacking direction) (see FIG. 4). At this time, the opening 211, the recess 221 and the opening 231 are overlapped with each other in the vertical direction. Further, the three intake holes 213 and the three intake holes 223 are overlapped so as to communicate with each other in the vertical direction. Further, a slope 233 is formed at a position of the front end frame 230 that overlaps the three intake holes 213 and the three intake holes 223 in the vertical direction. As will be described later, the three intake holes 213, the three intake holes 223 and the slope 233 form a part of the intake channel 70.

When the alignment frame 210, the back end frame 220, and the front end frame 230 are laminated in the vertical direction, the slit SL1, the slit SL2, and the opening 231 are overlapped so as to communicate with each other in the vertical direction. As will be described later, the slit SL1, the slit SL2 and the opening 231 form a part of the exhaust channel 80.

When the alignment frame 210, the back end frame 220, and the front end frame 230 are stacked in the vertical direction, the four through holes 212, the four flow paths 222, and the four flow paths 232 communicate with each other in the vertical direction. Can be stacked. A packing P1 is arranged between the alignment frame 210 and the back end frame 220. As a result, the space between the four through holes 212 and the four flow paths 222 is liquid-tightly sealed. Similarly, the packing P2 is arranged between the back end frame 220 and the front end frame 230. As a result, the space between the four flow paths 222 and the four flow paths 232 is liquid-tightly sealed.

<Head 50>
As shown in FIG. 4, a head 50 is joined to the lower surface of the front end frame 230 with an adhesive or the like. As shown in FIG. 3, the head 50 has an actuator unit 51 and a flow path member 55. The actuator unit 51 is laminated on the flow path member 55 in the direction perpendicular to the paper surface of FIG. 3 (vertical direction; corresponding to the stacking direction). The flow path member 55 includes two manifolds 58a and 58b, a plurality of pressure chambers 57, a plurality of nozzles 56, and a plurality of plates having a plurality of flow paths communicating them. Although not shown, a diaphragm covering the pressure chamber 57 is arranged on the uppermost layer of the plurality of plates, and a nozzle plate on which the nozzle 56 is formed is arranged on the lowermost layer of the plurality of plates.

As shown in FIG. 3, the plurality of nozzles 56 and the plurality of pressure chambers 57 form an eight-row nozzle row and an eight-row pressure chamber row, respectively. Each nozzle row and pressure chamber row extend in the left-right direction, and the eight nozzle rows and the eight pressure chamber rows are all arranged in the front-rear direction. In the two nozzle rows arranged in the front-rear direction, the positions of the nozzles 56 in the left-right direction are deviated from each other. Similarly, in the two pressure chamber rows arranged in the front-rear direction, the positions of the pressure chambers 57 in the left-right direction are deviated from each other.

As shown in FIG. 3, the pressure chambers 57 forming the pressure chamber rows from the first row to the fourth row from the rear communicate with the manifold 58a. The pressure chambers 57, which form the pressure chamber rows from the fifth row to the eighth row from the rear, communicate with the manifold 58b. The manifold 58a extends to the left from the ink inlet 51a located at the right end of the flow path member 55, makes a U-turn at the left end of the flow path member 55, extends to the right, and communicates with the ink outlet 52a. The manifold 58b extends to the left from the ink inlet 51b located at the right end of the flow path member 55, makes a U-turn at the left end of the flow path member 55, extends to the right, and communicates with the ink outlet 52b.

The actuator unit 51 has a plurality of individual electrodes 52 arranged at positions overlapping the pressure chambers 57 corresponding to the plurality of pressure chambers 57, a piezoelectric layer 53, and the opposite side of the individual electrodes 52 (piezoelectricity) with the piezoelectric layer 53 interposed therebetween. It has a common electrode (not shown) located below layer 53). The portion of the actuator unit 51 corresponding to each pressure chamber 57, that is, the portion overlapping the individual electrode 52 and the individual electrode 52 (or pressure chamber 57) of the piezoelectric layer 53, and the individual electrode 52 (or pressure) of the common electrode. The portion overlapping the chamber 57) and the portion overlapping the individual electrode 52 (or pressure chamber 57) of the vibrating plate correspond to the actuator of the present disclosure. That is, the actuator unit 51 has a plurality of actuators corresponding to the pressure chamber 57.

<Wiring part 40>
As shown in FIG. 5, a wiring portion 40 is joined to the upper surface of the actuator unit 51. As shown in FIG. 6, the wiring portion 40 mainly includes a COF 241 (an example of a flexible cable), a COF retainer 242, a spring retainer 243, and a printed circuit board 244.

As shown in FIG. 6, the COF 241 has a base portion 241B extending in the left-right direction (an example of the first part of the flexible cable) and a base portion 241B that is bent upward from both ends in the left-right direction and further inside in the left-right direction. It has a bent portion 241U that is folded back toward the surface and a driver 241D provided on the bent portion 241U. The base portion 241B of the COF 241 overlaps with the actuator unit 51 in the vertical direction, and a plurality of terminals (not shown) are formed on the lower surface of the base portion 241B. The plurality of terminals provided on the lower surface of the base portion 241B are electrically connected to the plurality of individual electrodes 252 and the common electrode. As a result, the driver 241D is electrically connected to the plurality of individual electrodes 252 and the common electrode via a plurality of terminals (not shown) provided on the lower surface of the base portion 241B. In FIG. 6, the COF 241 and the COF retainer 242, the spring retainer 243, and the printed circuit board 244 are shown in a state of being separated from each other in order to make the figure easier to see. However, in reality, as shown in FIG. 5, the bent portion 241U of the COF 241 is folded back in a U shape so as to sandwich the COF retainer 242, the spring retainer 243, and the printed circuit board 244. The COF retainer 242 is a substantially rectangular flat plate-shaped member, and is arranged on the base portion 241B of the COF 241. Both left and right ends of the COF retainer 242 project upward and support the bent portion 241U of the COF 241 from the inside. The spring retainer 243 has a substantially rectangular plate-shaped base portion 243B and two leaf spring portions 243S provided at both ends of the base portion 243 in the left-right direction. A printed circuit board 244 is arranged on the spring retainer 243. The printed circuit board 244 has a substantially rectangular plate-shaped base portion 244B and an extending portion 244E extending upward from the rear end of the base portion 244B. The leaf spring portion 243S of the spring retainer 243 abuts on the base portion 244B of the printed circuit board 244 from below, and pushes up the base portion 244B upward. The bent portions 241U of the COF 241 are arranged above both ends of the base portion 244B of the printed circuit board 244 in the left-right direction. When the spring retainer 243 pushes up the base portion 244B of the printed circuit board 244 upward, both end portions of the base portion 244B of the printed circuit board 244 in the left-right direction and the bent portion 241U of the COF 241 are brought into close contact with each other. As a result, the COF 241 and the printed circuit board 244 are electrically connected.

<Drive of head 50>
As shown in FIG. 7, behind the frame 20, the extending portion 244E of the printed circuit board 244 is pulled upward through the slits SL2 and SL1 and connected to the controller 7 (see FIG. 1). As a result, the driver 241D of the COF 241 is connected to the controller 7 via the printed circuit board 244. The controller 7 controls the driver 241D to constantly apply a ground potential to a common electrode (not shown), and selectively apply a ground potential and a driving potential to the individual electrodes 52.

The ink supplied from the ink tank to the ink supply port 51a reaches the pressure chamber 56 through the common passages 58a and 58b. The controller 7 applies a driving voltage between the common electrode (not shown) and the individual electrode 52 to drive the piezoelectric layer 53 and vibrate the diaphragm. Due to the vibration of the diaphragm, the pressure in the pressure chamber 57 becomes a positive pressure, ink is ejected from the nozzle 56, and the pressure in the pressure chamber 57 becomes a negative pressure, and the pressure chambers 56 from the common passages 58a and 58b Ink is supplied to. The ink that has not been supplied to the pressure chamber 57 passes through the manifolds 58a and 58b and reaches the ink discharge ports 52a and 52b. The ink discharged from the ink discharge ports 52a and 52b returns to the ink tank and is supplied to the ink supply ports 51a and 51b again.

<Intake channel 70 and exhaust channel 80>
Next, the intake channel 70 and the exhaust channel 80 will be described in detail with reference to FIG. 7. As shown in FIG. 7, a tube 271 is inserted into the intake hole 213 and the intake hole 223. In this embodiment, the intake channel 70 includes an intake hole 213, an intake hole 223, a slope 233, and a tube 271. The upper opening of the intake hole 213 corresponds to the inlet of the intake channel 70, and the lower end of the slope 233 corresponds to the outlet of the intake channel 70. One end of the tube 271 (lower end of FIG. 7) is in contact with the slope 233. The other end of the tube 271 is connected to an air pump (not shown), and air is supplied from the air pump.

As shown in FIG. 7, a slit SL1 is formed at a position of the frame 20 facing the intake hole 213 in the front-rear direction, and a slit SL2 is formed at a position facing the intake hole 223 in the front-rear direction. As described above, the extending portion 244E of the printed circuit board 244 is pulled out upward through the slits SL2 and SL1. The slits SL1 and SL2 not only function as a path for pulling out the extending portion 244E of the printed circuit board 244, but in the present embodiment, the slits SL1 and SL2 form a part of the exhaust channel 80.

As shown in FIG. 7, the air supplied from the air pump through the tube 271 passes through the inside of the tube 271 and flows down through the intake holes 213 and 223. The end of the tube 271 is located at the lower opening of the intake hole 223. Here, the air emitted from the tube 271 hits the slope 233. The slope 233 is inclined so as to go downward toward the rear. By hitting the slope 233, the air flowing downward changes its direction so that it flows backward, and passes through the gap between the lower side of the base 244B of the printed circuit board 244 and the COF retainer 242 to the rear. It flows toward. Then, the air that has flowed backward through the gap between the lower side of the base portion 244B of the printed circuit board 244 and the COF holding 242 flows upward through the slit SL2, and is further discharged upward through the slit SL1. Will be done.

As shown in FIG. 5, the intake hole 213 and the intake hole 223 are located on the front side of the frame 20, and the slit SL2 and the slit SL1 (see FIG. 4) are located on the rear side of the frame 20. As described above, the air that has passed through the intake hole 223 flows backward through the gap between the lower side of the base portion 244B of the printed circuit board 244 and the COF holding 242 (see FIG. 7). The direction in which the air flows at this time is the direction from the front to the rear, and intersects the direction in which the ink flows (the direction from left to right or the direction from right to left; see FIG. 3) at the manifolds 58a and 58b. doing.

As shown in FIG. 4, the position of the intake hole 213 in the left-right direction is substantially the same as the position of the slit SL1 in the left-right direction. As shown in FIG. 5, the position of the intake hole 223 in the left-right direction is substantially the same as the position of the slit SL2 in the left-right direction. That is, the positions of the intake holes 213 and 223 and the slits SL1 and SL2 in the left-right direction are almost the same. The intake holes 213 and 223 and the slits SL1 and SL2 are located substantially in the center of the actuator unit 51 in the left-right direction. In other words, the intake holes 213 and 223 and the slits SL1 and SL2 are located substantially in the center of the manifolds 58a and 58b in the left-right direction. Therefore, the air that has passed through the intake hole 223 flows above the substantially center of the manifolds 58a and 58b in the left-right direction in the gap between the lower side of the base portion 244B of the printed circuit board 244 and the COF holding 242.

<Effect of the first embodiment>
The black arrow in FIG. 7 represents the flow of air. As shown in FIG. 7, the air supplied from the air pump through the tube 271 flows backward through the gap between the lower side of the base 244B of the printed circuit board 244 and the COF retainer 242, and flows backward through the slit SL2. , Is discharged upward through SL1. That is, the air supplied through the intake channel 70 flows from the front to the rear through the gap between the lower side of the base portion 244B of the printed circuit board 244 and the COF holding 242, and flows upward through the exhaust channel 80. It is discharged. In the present embodiment, since the straight line connecting the intake channel 70 and the exhaust channel 80 is located in the gap between the lower side of the base portion 244B of the printed circuit board 244 and the COF retainer 242, the intake channel 70 is exited. Air enters the exhaust channel 80 through the gap between the underside of the base 244B of the printed circuit board 244 and the COF retainer 242. The base portion 241B of the COF 241 is arranged below the gap between the base portion 244B of the printed circuit board 244 and the COF holding 242. Terminals (not shown) are provided on the back surface of the base portion 241B, and are electrically connected to the individual electrodes 52 and the common electrodes of the actuator unit 51. Since the actuator unit 51 generates heat as the head 50 is driven, the heat is also transmitted to the flow path member 55, and the temperature of the ink inside the flow path member 55 rises. Since the plurality of actuators of the actuator unit 51 do not generate heat uniformly, temperature variation (temperature unevenness) may occur among the plurality of actuators. Along with this, the temperature of the ink may vary among the plurality of pressure chambers 57.

In the present embodiment, the frame 20 is provided with the intake channel 70 and the exhaust channel 80, and air can flow above the base portion 241B of the COF 241. Therefore, the temperature of the air in the vicinity of the base portion 241B can be lowered. If the base portion 241B can be cooled in this way, the actuator unit 51 can be indirectly cooled through the cooling of the base portion 241B. As a result, it is possible to reduce the temperature variation among the plurality of actuators of the actuator unit 51, and accordingly, it is possible to reduce the ink temperature variation among the plurality of pressure chambers 57.

The intake channel 70 includes intake holes 213 and 223 extending in the vertical direction and a slope 233 provided so as to face the lower opening of the intake hole 223. The slope 233 is inclined so as to be inclined downward toward the rear. Therefore, by applying the air flowing downward along the intake holes 213 and 223 to the slope 233, it is possible to suppress the generation of turbulent flow and efficiently flow the air backward. As a result, air can be efficiently flowed above the base portion 241B of the COF 241 and the base portion 241B can be cooled.

The intake channel 70 has a tube 271 inserted into the intake holes 213 and 223 extending in the vertical direction. The tip of the tube 271 is located at a position facing the slope 233 in the vertical direction. By simply inserting a tube into the intake holes 213 and 223 formed in the frame 20, a supply path for supplying air toward the intake channel 70 can be easily configured.

The intake channel 70 and the exhaust channel 80 are located between both ends of the manifolds 58a and 58b in the left-right direction in the left-right direction in which the manifolds 58a and 58b extend. Therefore, it is possible to cool the portion of the actuator unit 51 between the left and right ends of the manifolds 58a and 58b rather than the left and right ends of the manifolds 58a and 58b. Since the temperature-adjusted ink is supplied to the manifolds 58a and 58b, it is said that the temperature variation of the liquid is smaller in the vicinity of both ends of the manifolds 58a and 58b in the left-right direction than in the portion between the two ends in the left-right direction. Conceivable. In the present embodiment, the intake channel 70 and the exhaust channel 80 are located between both ends of the manifolds 58a and 58b in the left-right direction in the left-right direction in which the manifolds 58a and 58b extend. Therefore, it is possible to efficiently cool the portion of the actuator unit 51 in which the temperature varies widely among the plurality of actuators. In particular, in the present embodiment, the intake channel 70 and the exhaust channel 80 are located near the center of the manifolds 58a and 58b in the left-right direction in which the manifolds 58a and 58b extend. Therefore, the central portion in the left-right direction, which is considered to have the largest temperature variation among the plurality of actuators of the actuator unit 51, can be efficiently cooled.

In the present embodiment, as shown in FIG. 5, the intake holes 213 and the intake holes 223 of the intake channel 70 are located on the front side of the frame 20, and the slits SL2 and SL1 of the exhaust channel 80 (see FIG. 4) are located. It is located behind the frame 20. Therefore, the direction of air flow between the intake channel 70 and the exhaust channel 80 is the direction from the front to the rear, and the direction in which the ink flows through the manifolds 58a and 58b (the direction from left to right or the direction from right to left). It intersects with the direction toward (see Fig. 3). As described above, since the temperature-controlled ink is supplied to the manifolds 58a and 58b, the vicinity of the center of the manifolds 58a and 58b in the left-right direction is compared with the portion between both ends in the left-right direction of the actuator unit 51. It is considered that the temperature variation among a plurality of actuators is large. The portion of the actuator unit 51 near the center of the manifolds 58a and 58b in the left-right direction, where the temperature variation between the plurality of actuators of the actuator unit 51 is considered to be larger than that between both ends in the left-right direction, is the portion in the left-right direction of the actuator unit 51. It is considered that it is distributed in a band shape in the anteroposterior direction near the center. If air is flowed through the manifolds 58a and 58b in parallel with the direction in which the ink flows, it is difficult to flow air through the entire band-shaped portion. On the other hand, in the present embodiment, since the air is flowed in the direction in which the manifolds 58a and 58b intersect in the direction in which the ink flows, the air can be efficiently flowed toward the entire band-shaped portion.

<Second Embodiment>
A second embodiment of the present invention will be described with reference to the drawings. The same reference numerals are given to the same configurations as those in the first embodiment, and the description thereof will be omitted.

The head unit 110 (an example of a head module) according to the second embodiment has a wiring unit 30 instead of the wiring unit 40. As shown in FIG. 8, the wiring portion 30 according to the present embodiment includes a COF 241 (an example of a flexible cable), a COF retainer 340 (an example of a flexible cable fixing member), an air guide 350, a spring retainer 243, and the like. It mainly includes a printed circuit board 244.

As shown in FIG. 8, the COF retainer 340 is a substantially rectangular flat plate-shaped member, which is arranged on the base portion 241B of the COF 241. Similar to the COF retainer 242 of the first embodiment, both ends of the COF retainer 340 in the left-right direction project upward. The COF retainer 340 is provided with two inflow holes 341a and 341b and two outflow holes 342a and 342b. The inflow hole 341a is located on the left side of the center line C1 in the left-right direction of the COF retainer 340 and on the front side of the center line C2 in the front-rear direction. The inflow hole 341b is located on the right side of the center line C1 in the left-right direction of the COF retainer 340 and on the front side of the center line C2 in the front-rear direction. The outflow hole 342a is located on the left side of the center line C1 in the left-right direction of the COF retainer 340 and on the rear side of the center line C2 in the front-rear direction. The outflow hole 342b is located on the right side of the center line C1 in the left-right direction of the COF retainer 340 and on the rear side of the center line C2 in the front-rear direction. As shown in FIG. 10, a recess 343 (an example of a first separation portion) is formed on the lower surface of the COF retainer 340 over almost the entire lower surface of the COF retainer 340. As a result, the outer peripheral portion 344 (an example of the contact portion) surrounding the recess 343 on the lower surface of the COF retainer 340 projects below the recess 343. Further, on the lower surface of the COF retainer 340, in the portion surrounded by the two inflow holes 341a and 341b and the two outflow holes 342a and 342b at the substantially center of the recess 343, the recess 345 further recessed from the recess 343 (the first). 2 An example of a separated portion) is formed. The COF retainer 340 is in contact with the base portion 241B of the COF 241 at the outer peripheral portion 344. The gap between the recess 344 of the COF retainer 340 and the base 241B of the COF 241 is larger than the gap between the recess 343 of the COF retainer 340 and the base 241B of the COF 241.

As shown in FIG. 8, the air guide 350 is a substantially H-shaped plate-shaped member, and is arranged above the COF retainer 340. A spring retainer 243 is arranged above the air guide 350, and a printed circuit board 244 is arranged above the spring retainer 243. As shown in FIG. 9, the guide flow path 355a (an example of the guide flow path of the air guide) and the guide flow path 355b are both cut in a substantially rectangular shape in the substantially center of the air guide 350 in the left-right direction. It is formed as a notch. By forming the two guide flow paths 355a and 355b, the air guide 350 has a wide portion 351 provided on both sides of the air guide 350 in the left-right direction and a wide portion 351 having a length (width) in the front-rear direction. A narrower portion 352, which is shorter than the narrow portion 352, is formed. The guide flow path 355a is located on the front side of the narrow portion 352, and the guide flow path 355b is located on the rear side of the narrow portion 352. The narrow portion 352 extends in the left-right direction so as to connect substantially the center of the two wide portions 351 in the front-rear direction.

As shown in FIG. 9, when the COF retainer 340 and the air guide 350 are overlapped in the vertical direction, a part of the two inflow holes 341a and 341b is exposed from the guide flow path 355a, and the guide flow paths 355b to 2 are exposed. Part of the outflow holes 342a and 342b is exposed. Further, the guide flow path 355a and the slope 233 are arranged so as to face each other in the front-rear direction, and the length of the slope 233 in the left-right direction and the length of the guide flow path 355a in the left-right direction are the same.

Further, as shown in FIG. 10, at the end of the narrow portion 352 of the air guide 350 on the guide flow path 355a side in the front-rear direction, a slope 356 (air flow adjusting member in the middle portion) that inclines downward toward the rear. An example) is formed. As a result, the cross-sectional area when the guide flow path 355a is cut in a horizontal plane (a plane perpendicular to the vertical direction) gradually increases from the upper side to the lower side. That is, the cross-sectional area when the guide flow path 355a is cut in a horizontal plane is the smallest in the upper opening 357 of the guide flow path 355a (corresponding to the inlet of the guide flow path), and the lower opening 358 of the guide flow path 355a (guide flow path). In the part between the upper opening 357 and the lower opening 358 of the guide flow path 355a in the vertical direction (corresponding to the middle part of the guide flow path), it gradually increases toward the lower side. Become.

<Effect of the second embodiment>
As shown in FIG. 8, in the present embodiment, the wiring portion 30 has a COF retainer 340 and an air guide 350. Inflow holes 341a and 341b and outlets 342a and 342b are formed in the COF retainer 340. The black arrow shown in FIG. 11 indicates the flow of air. As shown in FIG. 11, the air supplied from the air pump through the tube 271 flows toward the inflow holes 341a and 341b by hitting the air guide 350. The air flowing through the inflow holes 341a and 341b passes through the gap between the surface (lower surface) of the base 241B of the COF 241 opposite to the surface (lower surface) provided with the terminal (not shown) and the COF retainer 340. It flows backward. As a result, air can flow on the upper surface of the base portion 241B of the COF 241, so that the temperature of the air in the vicinity of the base portion 241B can be lowered. As a result, as described above, the actuator unit 51 can be indirectly cooled through the cooling of the base portion 241B, and the temperature variation among the plurality of actuators of the actuator unit 51 can be reduced. Along with this, it is possible to reduce the variation in the temperature of the ink among the plurality of pressure chambers 57.

As shown in FIG. 11, on the lower surface side of the COF retainer 340, the air that has passed through the inflow holes 341a and 341b flows backward through the gap between the upper surface of the base 241B of the COF 241 and the COF retainer 340. As a result, the back side portion (an example of the second portion) of the base portion 241B of the COF 241 provided with the terminal (not shown) formed the air flow path. As a result, the back side of the base portion 241B of the COF 241 provided with the terminal (not shown) can be directly air-cooled by the air flowing rearward through the gap between the upper surface of the base portion 241B of the COF 241 and the COF holding 340. can.

As shown in FIG. 11, the inflow holes 341a and 341b of the COF retainer 340 are provided at positions overlapping in the vertical direction with the portion of the base portion 241B of the COF 241 provided with a terminal (not shown). Therefore, the unheated air taken in from the outside through the tube 271 can be guided toward the base 241B of the COF 241, and the base 241B of the COF 241 can be efficiently air-cooled.

As shown in FIG. 9, the guide flow path 355a of the COF retainer 340 is arranged so as to overlap the two inflow holes 341a and 341b in the vertical direction. As a result, the air flowing toward the guide flow path 355a of the COF retainer 340 can be efficiently guided toward the inflow holes 341a and 341b.

As shown in FIG. 10, at the end of the narrow portion 352 of the air guide 350 on the guide flow path 355a side in the front-rear direction, a slope 356 that inclines downward toward the rear is formed. As a result, the air flowing downward from the upper opening of the guide flow path 355a can be guided diagonally downward along the inclination direction of the slope 346.

As shown in FIGS. 8 and 9, the outflow holes 342a and 342b are open to the top surface (upper surface) of the COF retainer 340. In the gap between the upper surface of the base portion 241B of the COF 241 and the COF retainer 340, the air warmed by the heat generated by the actuator unit 51 and lightened can be efficiently discharged upward.

A recess 343 is formed on the lower surface of the COF retainer 340 over almost the entire lower surface of the COF retainer 340. As a result, a gap can be secured between the recess 343 of the COF retainer 340 and the upper surface of the base portion 241B of the COF 241, and an air flow path between the upper surface of the base portion 241B of the COF 241 and the upper surface of the COF retainer 340 can be secured. can. Further, a recess 344 is formed on the lower surface of the COF retainer 340, and the gap between the recess 344 of the COF retainer 340 and the base 241B of the COF 241 is between the recess 343 of the COF retainer 340 and the base 241B of the COF 241. Greater than the gap. As a result, the resistance of the air flow path between the upper surface of the base portion 241B of the COF 241 and the COF holding 340 can be reduced, and air can flow efficiently.

The embodiments disclosed this time are exemplary in all respects and are not restrictive. For example, the first embodiment and the second embodiment can be combined. Moreover, not all of the configurations shown in the first embodiment and the second embodiment are indispensable, and the configurations can be omitted if necessary. Further, the number, configuration, etc. of the inkjet heads 4 can be changed. Further, the number, arrangement, etc. of the nozzle 56 and the pressure chamber 57 can be changed as appropriate.

In each of the above embodiments, the number, shape, arrangement, etc. of the intake channel and the exhaust channel can be changed as appropriate. For example, in each of the above embodiments, the intake channel and the exhaust channel each have three air flow paths, but the present invention is not limited to such an embodiment and has an arbitrary number of air flow paths. You may be doing it. Further, in each of the above embodiments, the tube 271 is inserted into the intake holes 213 and 223, but the present invention is not limited to such an embodiment. For example, a connector for connecting the tube 271 may be attached to the intake hole 213, and the tube 271 may be attached to the connector.

In the second embodiment, a substantially H-shaped plate-shaped air guide 350 is provided as the air guide, but the present invention is not limited to such an embodiment. The shape of the air guide can be changed as needed. Further, the air guide does not necessarily have to be a plate-shaped air guide. For example, the tube 271 may be inserted to the vicinity of the inflow holes 341a and 341b. In this case, the tube 271 is the COF holder 340. It functions as an air guide that guides the flow of air toward the inflow holes 341a and 341b.

In the second embodiment, the COF retainer 340 is formed with two inflow holes 341a and 341b and two outflow holes 342a and 342b. However, the present invention is not limited to such an embodiment. The number of inflow holes and outflow holes can be arbitrary. The inflow hole and the outflow hole do not necessarily have to be through holes, and may be notches.

Also, the technical features described in each embodiment can be combined with each other. The scope of the present invention is intended to include all modifications within the scope of the claims and the scope equivalent to the scope of the claims.

1 Printer 4 Inkjet head 20 Frame 30, 40 Wiring part 50 Head

Claims (10)

A head having a plurality of pressure chambers and a flow path member in which a manifold communicating with the plurality of pressure chambers is formed, and a plurality of actuators having a plurality of individual electrodes corresponding to the plurality of pressure chambers.
A flexible cable arranged so as to overlap the plurality of actuators in the stacking direction, and having a first portion having a plurality of terminals connected to the plurality of individual electrodes formed on the first surface thereof. ,
A flexible cable fixing member in which an inflow hole and an exhaust hole are formed and arranged so as to face the second surface of the flexible cable, which is the back surface of the first surface.
A head module including an air guide configured to guide the flow of air toward the inflow hole of the flexible cable fixing member. The second portion of the second surface of the flexible cable, which overlaps with the first portion, forms a part of the air flow path connecting the inflow hole and the outflow hole of the flexible cable fixing member. The head module according to claim 1. The head module according to claim 2, wherein the inflow hole is arranged at a position overlapping the second portion of the flexible cable in the stacking direction. The air guide has a guide flow path.
The head module according to any one of claims 1 to 3, wherein the guide flow path of the air guide is located at a position overlapping the inflow hole in the stacking direction. The guide flow path includes an inlet, an outlet closer to the inflow hole than the inlet, and an intermediate portion located between the inlet and the outlet in the stacking direction.
The head module according to claim 4, wherein the intermediate portion includes an air flow adjusting member that directs air flowing in the stacking direction from the inlet in a direction different from the stacking direction. The orthogonal cross-sectional area of the inlet of the guide flow path, which is the area of the cross section orthogonal to the stacking direction, is smaller than the orthogonal cross-sectional area of the outlet and the orthogonal cross-sectional area of the intermediate portion.
The head module according to claim 5, wherein the orthogonal cross-sectional area of the intermediate portion of the guide flow path is smaller than the orthogonal cross-sectional area of the outlet. The head module according to claim 2, wherein the outflow hole is opened on the upper surface of the flexible cable fixing member in the stacking direction. The surface of the flexible cable fixing member facing the second surface of the flexible cable is located between the abutting portion of the flexible cable in contact with the second surface and the second surface of the flexible cable. The head module according to claim 2, wherein the head module includes a separating portion forming a gap. The separated portion of the flexible cable fixing member is
A first separation portion forming a first gap between the flexible cable and the second surface,
The head module according to claim 8, further comprising a second separated portion forming a second gap larger than the first gap between the flexible cable and the second surface. A printing apparatus comprising the head module according to any one of claims 1 to 9.

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