JP2021138025A - Liquid discharge head and liquid discharge device - Google Patents

Abstract

To provide a liquid discharge head which can inhibit temperature rise of a liquid, and to provide a liquid discharge device.SOLUTION: A liquid discharge head according to an embodiment comprises a liquid discharge part, an inflow pipe part, an outflow pipe part, and a cooling device. The liquid discharge part includes: a first common chamber; an actuator forming pressure chambers connected to the first common chamber; and a second common chamber connected to the pressure chambers. The inflow pipe part supplies a liquid to the first common chamber. The outflow pipe part discharges the liquid from the second common chamber. The cooling device includes: a cooling plate thermally connected to the outflow pipe part; and a cooling passage which is provided at the cooling plate and through which a coolant passes.SELECTED DRAWING: Figure 4

Description

Embodiments of the present invention relate to a liquid discharge head and a liquid discharge device.

As a liquid discharge head used in various liquid discharge devices, a technique is known in which a plurality of pressure chambers are provided, a driving element is driven to deform the volume of the pressure chamber, and the liquid in the pressure chamber is discharged from a nozzle. .. As a specific example, the liquid discharge head has a liquid discharge portion having a common chamber on each of the primary side and the secondary side of a plurality of pressure chambers. The liquid flowing through the liquid discharge section flows into the common chamber on the primary side of the plurality of pressure chambers, passes through the plurality of pressure chambers, and passes through the common chamber on the secondary side of the plurality of pressure chambers. It is discharged to the secondary side. Then, as the volume of the pressure chamber increases or decreases, the liquid in the pressure chamber is discharged as droplets from the nozzle.

The liquid discharge head is connected to a common chamber provided on each of the primary side and the secondary side of the plurality of pressure chambers, and is connected to a circulation device that circulates the liquid.

Japanese Unexamined Patent Publication No. 2015-150740

An object to be solved by the present invention is to provide a liquid discharge head and a liquid discharge device capable of suppressing a temperature rise of a liquid.

The liquid discharge head according to one embodiment includes a liquid discharge portion, an inflow pipe portion, an outflow pipe portion, and a cooling device. The liquid discharge unit includes a first common chamber, actuators constituting a plurality of pressure chambers connected to the first common chamber, and a second common chamber connected to the plurality of pressure chambers. The inflow pipe portion supplies the liquid to the first common chamber. The outflow pipe portion discharges the liquid from the second common chamber. The cooling device includes a cooling plate that is thermally connected to the outflow pipe portion, and a cooling flow path that is provided on the cooling plate and through which cooling water passes.

The perspective view which shows typically the structure of the liquid discharge head which concerns on 1st Embodiment. The side view which shows typically the structure of the plurality of head devices used for the liquid discharge head. The plan view which shows the structure of the plurality of head devices schematically. The side view which shows the structure of the head device. The perspective view which shows the main part structure of the head device. The side view which shows the main part structure of the head device. The cross-sectional view which shows the structure of the liquid discharge part used for this head device. The side view which shows typically the structure of the cooling device used for the head device. The explanatory view which shows typically the structure of the liquid discharge device which uses the same liquid discharge head. The side view which shows typically the structure of the head apparatus of the liquid discharge head which concerns on 2nd Embodiment. The side view which shows typically the structure of the head apparatus of the liquid discharge head which concerns on 3rd Embodiment. The plan view which shows typically the structure of the head apparatus of the liquid discharge head which concerns on 4th Embodiment. The side view which shows typically the structure of the head apparatus of the liquid discharge head which concerns on 5th Embodiment. The side view which shows typically the structure of the head apparatus of the liquid discharge head which concerns on 6th Embodiment. The plan view which shows the structure of the head device schematically.

Hereinafter, the liquid discharge head 1 and the liquid discharge device 100 according to the first embodiment will be described with reference to FIGS. 1 to 9.

FIG. 1 is a perspective view schematically showing the configuration of the liquid discharge head 1 according to the first embodiment. 2 and 3 are diagrams schematically showing the configuration of a plurality of head devices 5 used for the liquid discharge head 1. Further, FIG. 2 is a side view and FIG. 3 is a plan view. Further, in FIGS. 2 and 3, a part of the plurality of head devices 5 is omitted, and an example in which the three head devices 5 are arranged is shown.

FIG. 4 is a side view showing the configuration of the head device 5. 5 and 6 are diagrams showing the configurations of the liquid discharge portion 10, a part of the circuit board 12, the part of the cooling device 13, and the outflow pipe portion 15 as the main components of the head device 5. Further, FIG. 5 is a perspective sectional view, and FIG. 6 is a sectional view.

FIG. 7 is a cross-sectional view showing the configuration of the liquid discharge unit 10 used in the head device 5. FIG. 8 is a side view schematically showing the configuration of the cooling device 13 used in the head device 5. FIG. 9 is an explanatory diagram schematically showing the configuration of the liquid discharge device 100 in which the liquid discharge head 1 is used.

In the figure, X, Y, and Z indicate three directions orthogonal to each other. The X direction is a direction along the longitudinal direction of the actuator 21, in other words, an arrangement direction of a plurality of grooves 211 constituting the pressure chamber D provided in the actuator 21. The Y direction is a direction along the longitudinal direction of the groove 211 of the actuator 21. The Z direction is a direction along the opposite direction of the actuator 21 and the nozzle plate 24, in other words, a direction along the ink ejection direction from the nozzle 241 of the nozzle plate 24. Hereinafter, the description will be made using the X, Y, and Z directions.

Further, in each figure, for convenience of explanation, the configuration is shown enlarged, reduced or omitted as appropriate. Further, in each figure, the flow of the liquid is indicated by a solid arrow, and the flow of the cooling water is indicated by a broken line arrow.

As shown in FIGS. 1 and 2, the liquid discharge head 1 includes, for example, an outer case 4 and a plurality of head devices 5 housed in the outer case 4. In FIG. 2, a part of the outer case 4 and the head device 5 is omitted.

For example, the liquid discharge head 1 is provided in a liquid discharge device 100 such as the inkjet recording device shown in FIG. The liquid discharge head 1 is a circulation type head that is connected to a circulation device 2 including a supply tank 132 as a liquid storage unit provided in the liquid discharge device 100 and circulates ink with the supply tank 132.

As shown in FIGS. 2 to 6, the head device 5 includes a liquid discharge portion 10, a circuit board (board) 12, a cooling device 13, an inflow pipe portion 14, and an outflow pipe portion 15. .. In the head device 5 of FIG. 2, the inflow pipe portion 14 and the outflow pipe portion 15 are omitted.

For example, in the head device 5, the liquid discharge portion 10, the circuit board 12, the cooling device 13, the inflow pipe portion 14, and the outflow pipe portion 15 are integrally assembled. The head device 5 may be configured to integrally hold the liquid discharge portion 10, the circuit board 12, the cooling device 13, the inflow pipe portion 14 and the outflow pipe portion 15 by a base plate or the like.

The head device 5 is, for example, a share mode share wall type head. For example, as shown in FIGS. 1 and 2, a plurality of head devices 5 are arranged so as to be laminated with adjacent head devices 5. The number of head devices 5 is appropriately set. The head device 5 is configured as a liquid discharge head 1, and when provided in the liquid discharge device 100, for example, the nozzle 24a described later of the liquid discharge unit 10 is arranged in a posture of facing downward in the direction of gravity.

As shown in FIGS. 5 to 7, the liquid discharge unit 10 includes an actuator 21, a pair of cover plates 22 covering both main surfaces of the actuator 21, and a pair of streams covering both main surfaces of the actuator 21 and the cover plate 22. A road cover 23 and a nozzle plate 24 are provided.

The actuator 21 is formed in a plate shape that is long in one direction. The actuator 21 is formed in a plate shape, for example, by a laminated piezoelectric body in which a pair of piezoelectric members are laminated. For example, PZT (lead zirconate titanate) is used as the piezoelectric member. The pair of piezoelectric members are polarized.

As shown in FIGS. 5 to 7, the end portion of the actuator 21 facing the nozzle plate 24 has a plurality of grooves 211, a plurality of wall-shaped drive element portions 212, and an electrode 213. The end portion of the actuator 21 is formed in a comb-teeth shape in which a plurality of grooves 211 and drive element portions 212 are alternately arranged side by side in the longitudinal direction of the actuator 21 which is the X direction. That is, a plurality of drive element portions 212 are formed on the end surface of the actuator 21 on the nozzle plate 24 side, and the plurality of drive element portions 212 are separated from each other in the X direction and are adjacent to each other, so that the plurality of drive element portions 212 are located between the adjacent drive element portions 212. Each groove 211 is configured.

As shown in FIG. 7, the electrode 213 is formed on the inner wall of each groove 211. For example, each electrode 213 is wired to the drive element portion 212 on the actuator 21. Each electrode 213 is electrically connected to the driver IC 43 via, for example, the flexible wiring board 42 described later of the circuit board 12.

The pair of cover plates 22 cover the main surface of the actuator 21 in a direction orthogonal to the longitudinal direction of the actuator 21 and in a direction orthogonal to the opposite direction of the actuator 21 and the nozzle plate 24. That is, the pair of cover plates 22 cover the main surface of the actuator 21 in the Y direction.

As shown in FIGS. 5 to 7, the cover plate 22 has a plurality of notches 221 formed in the same shape as the grooves 211 provided in the actuators 21 facing each other in the Y direction. One of the pair of cover plates 22 forms a first cover plate provided on the main surface of the actuator 21 on the primary side in the liquid flow direction along the Y direction in the groove 211, and the other forms the Y in the groove 211. A second cover plate provided on the main surface of the actuator 21 on the secondary side in the flow direction of the liquid along the direction is formed.

The plurality of notches 221 face every other groove 211 provided in the actuator 21 in the arrangement direction of the grooves 211. That is, the cover plate 22 opens the openings in the Y direction of every other plurality of grooves 211 among the plurality of grooves 211 by the notches 221 and the openings in the Y direction of the other plurality of grooves 211 every other one. Is closed by a region not provided with a notch 221.

In other words, as shown in FIG. 7, the actuator 21 and the cover plate 22 are formed by a plurality of air chambers C in which openings at both ends of the groove 211 in the Y direction are closed by a pair of cover plates 22 and a pair of cover plates 22. The notch 221 constitutes a plurality of pressure chambers D in which the openings at both ends of the groove 211 in the Y direction are opened. Then, these air chambers C and pressure chambers D are alternately arranged in parallel along the X direction.

As shown in FIGS. 5 and 6, the flow path cover 23 is formed in a plate shape. For example, the flow path cover 23 has a part of the surface facing the actuator 21 and the cover plate 22 recessed. The pair of flow path covers 23 cover the outer surfaces of the actuator 21 and the cover plate 22 in the Y direction.

One of the pair of flow path covers 23 forms a first flow path cover that covers the main surface of the actuator 21 on the primary side and the cover plate 22 in the liquid flow direction along the Y direction in the groove 211. The other of the pair of flow path covers 23 forms a second flow path cover that covers the main surface of the actuator 21 on the secondary side and the cover plate 22 in the liquid flow direction along the Y direction in the groove 211.

As shown in FIGS. 5 and 6, the flow path cover 23 (first flow path cover 23) that covers the main surface of the actuator 21 on the primary side and the cover plate 22 is a cover plate that covers the primary side in the Y direction of the actuator 21. A first common chamber E communicating with the pressure chamber D is formed between the 22 (first cover plate 22). The first common chamber E extends in the X direction and is fluidly connected to all pressure chambers D. The first common chamber E communicates with the inflow pipe portion 14. The first common chamber E constitutes an inflow passage that communicates the inflow pipe portion 14 and the plurality of pressure chambers D.

As a specific example, the first common chamber E communicates with the inflow pipe portion 14 at both ends in the longitudinal direction. Further, the first common chamber E is arranged on the primary side of the plurality of pressure chambers D, and supplies the liquid flowing from the inflow pipe portion 14 to the plurality of pressure chambers D.

As shown in FIGS. 5 and 6, the flow path cover 23 (second flow path cover 23) that covers the main surface of the actuator 21 on the secondary side and the cover plate 22 covers the secondary side in the Y direction of the actuator 21. A second common chamber F communicating with the pressure chamber D is formed between the cover plate 22 (second cover plate 22). The second common chamber F extends in the X direction and is fluidly connected to all the pressure chambers D. The second common room F communicates with the outflow pipe portion 15. The second common chamber F constitutes an outflow passage that communicates the plurality of pressure chambers D and the outflow pipe portion 15.

As a specific example, the second common chamber F communicates with the outflow pipe portion 15 at both ends in the longitudinal direction. Further, the second common chamber F is arranged on the secondary side of the plurality of pressure chambers D, and the liquid flowing out from the plurality of pressure chambers D is discharged to the pair of outflow pipe portions 15.

As shown in FIG. 5, the nozzle plate 24 is formed in a plate shape that is long in one direction. As shown in FIGS. 5 to 7, the nozzle plate 24 has, for example, a plurality of nozzles 241 arranged in parallel in the X direction facing the pressure chamber D. The nozzle plate 24 includes one row or a plurality of rows of nozzles formed by arranging a plurality of nozzles 241. Each nozzle 241 is a through hole penetrating between both main surfaces of the nozzle plate 24.

As shown in FIGS. 2 to 6, the circuit board 12 includes a control board 41, a flexible wiring board 42 provided on the control board 41, and a driver IC 43 provided on the flexible wiring board 42. The control board 41 has, for example, a rectangular plate shape. The control board 41 is arranged between the inflow pipe portion 14 and the outflow pipe portion 15 in the X direction. The control board 41 is, for example, a board that drives and controls the driver IC 43.

A single or a plurality of flexible wiring boards 42 are provided. In this embodiment, an example is shown in which a single flexible wiring board 42 is provided. When a plurality of flexible wiring boards 42 are provided, the plurality of flexible wiring boards 42 are arranged in parallel in the X direction. One end of the flexible wiring board 42 is connected to the control board 41 in the Z direction, and the other end is connected to a plurality of electrodes 213 of the actuator 21.

The driver IC 43 is mounted on the main surface of the flexible wiring board 42 on the side facing the cooling plate 51 of the cooling device 13 in the Y direction. The driver IC 43 is arranged in contact with the cooling plate 51 of the cooling device 13 via, for example, grease or a sheet having high thermal conductivity. The driver IC 43 is electrically connected to the wiring and the electrode 213 on the control board 41 via the flexible wiring board 42.

As shown in FIGS. 4 and 8, the cooling device 13 includes a cooling plate 51, a cooling flow path 52, and a coolant supply circuit 55. The cooling device 13 cools a member in contact with the cooling plate 51 by using, for example, cooling water as a cooling liquid. In the present embodiment, the cooling device 13 cools the mounted product of the control board 41, the driver IC 43, a part of the liquid discharge section 10, and the outflow pipe section 15.

The cooling plate 51 is made of a metal material having excellent thermal conductivity, specifically, a stainless steel material or an aluminum material. The cooling plate 51 is thermally connected to the component to be cooled. For example, the cooling plate 51 is at least in contact with the outflow pipe portion 15 fluidly connected to the liquid discharge portion 10 of the adjacent head device 5, or is formed integrally with the outflow pipe portion 15.

As a specific example, the cooling plate 51 is thermally connected to a part of the control board 41, the driver IC 43, and a part of the liquid discharge part 10, and is in contact with a part of the outer surface of the outflow pipe part 15, or It is formed integrally with a part of the outflow pipe portion 15. In the present embodiment, one main surface of the cooling plate 51 is in contact with the heat-generating mounting product of the control board 41 and each driver IC 43, and the other main surface is in contact with the flexible wiring board 42 of the adjacent head device 5. Further, in the present embodiment, the cooling plate 51 contacts at least a part of one outer surface in the Z direction of the actuator 21 of the liquid discharge unit 10 and the second flow path cover 23. Although the example in which the cooling plate 51 contacts a part of the outer surface of the actuator 21 in the Y direction will be described in FIG. 6, the cooling plate 51 may be configured to contact the entire region of the outer surface of the actuator 21 in the Y direction. Further, in the present embodiment, one outer surface of the cooling plate 51 comes into contact with the outer surface of the outflow pipe portion 15 in the X direction. The cooling plate 51 has a cooling flow path 52 formed inside, and the outer surface of the region where the cooling flow path 52 exists comes into contact with each driver IC 43 and the outflow pipe portion 15.

The shape of the main surface of the cooling plate 51 is formed so as to face the heat-generating electronic components and the driver IC 43 mounted on the control board 41. As shown in FIG. 4, the main surface shape of the cooling plate 51 shows an example of an E-shape, but may be, for example, a rectangular shape or another shape.

As shown in FIGS. 4 to 6, the outer surface of the cooling plate 51 facing the liquid discharge portion 10 is formed in a flat shape, and among the outer surfaces of the actuator 21 of the liquid discharge portion 10 and the second flow path cover 23, the nozzle It contacts the outer surface on the opposite side of the plate 24 in the Z direction. Further, as shown in FIGS. 3 to 5, a part of the outer surface of the cooling plate 51 facing the outflow pipe portion 15 is formed in a flat shape and comes into contact with the outer surface of the outflow pipe portion 15. For example, the cooling plate 51 comes into contact with the outflow pipe portion 15 via a sheet, grease, adhesive, or the like having high thermal conductivity. Further, the outer surface of the cooling plate 51 facing the inflow pipe portion 14 is separated from the inflow pipe portion 14.

The cooling flow path 52 is formed by holes provided in the cooling plate 51. For example, as shown in FIGS. 3 and 4, in a posture in which the cooling plate 51 is assembled integrally with other configurations, the opening 521 on the primary side and the opening 522 on the secondary side are the liquid discharge portion 10 of the cooling plate 51. It is arranged on the outer surface opposite to the outer surface facing the above surface in the Z direction. Further, the primary side of the cooling flow path 52 is arranged on one side of the cooling plate 51 in the X direction, and the secondary side of the cooling flow path 52 is arranged on many sides of the cooling plate 51 in the X direction. More specifically, the primary side of the cooling flow path 52 is arranged on the outer surface side facing the outflow pipe portion 15 in the X direction of the cooling plate 51. In other words, a part of the outer surface of the cooling plate 51 on which the primary side of the cooling flow path 52 exists comes into contact with the outflow pipe portion 15.

To explain a specific example, the cooling flow path 52 is formed with an opening 521 on the primary side and an opening 522 on the secondary side of the cooling flow path 52 on both ends in the Z direction of the cooling plate 51 and in the X direction of one outer surface. NS. Further, for example, the opening 521 on the primary side is provided on the outflow pipe portion 15 side in the X direction of the cooling flow path 52. Further, the cooling flow path 52 is formed in the Z direction from one outer surface to the other outer surface side in the Z direction of the cooling plate 51 from the opening 521 on the primary side formed on one outer surface in the Z direction of the cooling plate 51. Extend. Further, the cooling flow path 52 extends from one side in the X direction to the other side at a position adjacent to the liquid discharge portion 10 of the cooling plate 51 and at a position where it passes over the driver IC 43. Further, the cooling flow path 52 extends in the Z direction from the other side of the cooling plate 51 in the X direction toward the opening 522 on the secondary side formed on one outer surface in the Z direction of the cooling plate 51. The shape and arrangement of the cooling flow path 52 are appropriately set depending on the arrangement of the driver IC 43, the distance between the driver IC 43 and the liquid discharge portion 10, the position of the outflow pipe portion 15, and the like.

The primary side opening 521 and the secondary side opening 522 of the cooling flow path 52 are connected to the coolant supply circuit 55 via, for example, pipes, tubes, joints, and the like. The coolant supply circuit 55 includes, for example, a flow path such as a pipe or a tube for supplying the coolant, and a pump. The coolant supply circuit 55 supplies the cooling water to the cooling flow path 52 by a pump from the opening 521 on the primary side, and collects the cooling water from the opening 522 on the secondary side that has passed through the cooling flow path 52.

As shown in FIGS. 3 and 4, the inflow pipe portion 14 is formed, for example, in the shape of a rectangular cylinder, and forms an inflow flow path 141 through which a liquid flows. The inflow pipe portion 14 is fixed to the liquid discharge portion 10. The inflow flow path 141 has, for example, a circular flow path cross-sectional shape orthogonal to the liquid flow direction, and has a constant flow path cross-sectional area. The primary side of the inflow flow path 141 is connected to the circulation device 2, and the secondary side is connected to the first common chamber E of the liquid discharge unit 10. The inflow pipe portion 14 is formed of, for example, a metal material having excellent thermal conductivity, and more specifically, a stainless steel material or an aluminum material as a more specific example.

As shown in FIGS. 3 to 5, the outflow pipe portion 15 is formed, for example, in the shape of a rectangular cylinder, and forms an outflow flow path 151 through which a liquid flows. The outflow pipe portion 15 is fixed to the liquid discharge portion 10. The outflow flow path 151 has, for example, a circular flow path cross-sectional shape orthogonal to the liquid flow direction, and has a constant flow path cross-sectional area. The primary side of the outflow flow path 151 is connected to the second common chamber F of the liquid discharge unit 10, and the secondary side is connected to the circulation device 2. The outflow pipe portion 15 is formed of, for example, a metal material having excellent thermal conductivity, and more specifically, a stainless steel material or an aluminum material as a more specific example.

One such inflow pipe portion 14 and one such outflow pipe portion 15 are provided in, for example, the liquid discharge portion 10. Further, the inflow pipe portion 14 is provided on one end side in the X direction of the liquid discharge portion 10, and the outflow pipe portion 15 is provided on the other end side in the X direction of the liquid discharge portion 10.

Next, the liquid discharge device 100 having the liquid discharge head 1 will be described with reference to FIG. As shown in FIG. 9, the liquid discharge device 100 includes a housing 111, a medium supply unit 112, an image forming unit 113, a medium discharge unit 114, a transfer device 115 as a support device, a control unit 116, and the like. To be equipped with.

The liquid discharge device 100 is, for example, an inkjet printer. The liquid discharge device 100 conveys, for example, paper P as a recording medium to be ejected along a predetermined transfer path A from the medium supply unit 112 to the medium discharge unit 114 through the image forming unit 113. Then, the liquid ejection device 100 ejects ink as a liquid to perform an image forming process on the conveyed paper P.

The medium supply unit 112 includes a plurality of paper cassettes 1121. The medium ejection unit 114 includes a paper ejection tray 1141. The image forming unit 113 includes a supporting portion 117 that supports the paper, and a plurality of head units 130 that are arranged so as to face each other above the supporting portion 117.

The support portion 117 includes a transport belt 118 provided in a loop shape in a predetermined area for image formation, a support plate 119 that supports the transport belt 118 from the back side, and a plurality of belt rollers 120 provided on the back side of the transport belt 118. , Equipped with.

The head unit 130 includes a plurality of liquid discharge heads 1 and a circulation device 2 connected to each liquid discharge head 1. The circulation device 2 includes, for example, a plurality of supply tanks 132 as liquid tanks mounted on each liquid discharge head 1, a connection flow path 133 connecting the liquid discharge head 1 and the supply tank 132, and a circulation unit. A circulation pump 134 is provided. The head unit 130 is a circulation type head unit that circulates a liquid.

In the present embodiment, the liquid ejection head 1 is provided with four liquid ejection heads 1 that eject four colors of ink, cyan, magenta, yellow, and black, as liquid. Further, the supply tank 132 is provided with four supply tanks 132 for accommodating the inks of each of these colors. The supply tank 132 is connected to the liquid discharge head 1 by the connection flow path 133. The connection flow path 133 includes a supply flow path 1331 connected to the inflow pipe portion 14 of the liquid discharge head 1 and a recovery flow path 1332 connected to the outflow pipe portion 15 of the liquid discharge head 1.

Further, a negative pressure control device such as a pump (not shown) is connected to the supply tank 132. Then, by controlling the inside of the supply tank 132 with a negative pressure control device according to the head value between the liquid discharge head 1 and the supply tank 132, the liquid supplied to each nozzle 241 of the liquid discharge head 1 is released. It is formed into a meniscus of a predetermined shape.

The circulation pump 134 is a liquid feeding pump composed of, for example, a piezoelectric pump. The circulation pump 134 is provided in the supply flow path 1331. The circulation pump 134 is connected to the control unit 116 by wiring, and is configured to be controllable by the control of the CPU (Central Processing Unit) 116a. The circulation pump 134 circulates the liquid in a circulation flow path including the liquid discharge head 1 and the supply tank 132.

The transport device 115 transports the paper P along the transport path A from the paper feed cassette 1121 of the medium supply unit 112 to the paper discharge tray 114a of the medium discharge unit 114 through the image forming unit 113. The transport device 115 includes a plurality of guide plate pairs 1211 to 1218 arranged along the transport path A, and a plurality of transport rollers 1221 to 1228. The transport device 115 supports the paper P so as to be relatively movable to the liquid discharge head 1.

The control unit 116 includes a CPU (Central Processing Unit) 1161 as an example of a processor, a ROM (Read Only Memory) for storing various programs, and a RAM (RAM) for temporarily storing various variable data and image data. It includes a Random Access Memory) and an interface unit that inputs data from the outside and outputs data to the outside.

According to the liquid discharge head 1 and the liquid discharge device 100 configured in this way, the liquid is discharged from the supply tank 132 and the connection flow path 133 from the inflow pipe portion 14 by driving the circulation pump 134 of the circulation device 2. And through the first common chamber E, it reaches a plurality of pressure chambers D.

When the liquid is discharged from the nozzle 241, the control unit 116 controls the driver IC 43, applies a drive voltage to the drive element unit 212, and discharges the liquid from the nozzle 241. As a specific example, the driver IC 43 applies a driving voltage to the electrodes 213 provided in the plurality of grooves 211 of the actuator 21. At this time, the driver IC 43 gives a potential difference between the electrodes 213 in the pressure chamber D to be driven and the electrodes 213 in the air chambers C on both sides. Then, as shown in one drive element portion 212 of FIG. 7, the pair of piezoelectric materials constituting the actuator 21 are deformed in opposite directions, and the drive element portion 212 is bent and deformed. The driver IC 43 alternately repeats bending deformation in different directions to increase or decrease the volume of the pressure chamber D, and discharges the liquid as droplets from the nozzle 241 facing the pressure chamber D.

Further, the liquid not discharged from the nozzle 241 is collected from the pressure chamber D through the second common chamber F, the outflow pipe portion 15 and the connection flow path 133 to the supply tank 132. In this way, the liquid supplied to the liquid discharge head 1 circulates in the circulation device 2 and the liquid discharge head 1.

When a driving voltage is applied to the electrode 213 to drive the driving element portion 212, the driving element portion 212 and the electrode 213 generate heat, so that the liquid passing through the pressure chamber D is heated. However, the liquid discharge head 1 of the present embodiment is configured such that a part of the outer surface of the cooling plate 51 of the cooling device 13 comes into contact with the outflow pipe portion 15. Therefore, when the liquid heated by passing through the pressure chamber D passes through the outflow pipe portion 15, heat is exchanged by the cooling plate 51, so that the liquid passing through the outflow pipe portion 15 is cooled.

Therefore, the circulation device 2 can prevent the temperature of the liquid from rising when the liquid that has passed through the head device 5 of the liquid discharge head 1 is collected and the liquid is supplied to the head device 5 again.

In this way, the liquid discharge head 1 can maintain the liquid circulated by the circulation device 2 at an appropriate temperature by cooling the liquid passing through the outflow pipe portion 15 by the cooling device 13. The liquid discharge head 1 can suppress an increase in the temperature of the liquid circulated by the circulation device 2. Therefore, the liquid discharge head 1 and the liquid discharge device 100 can suppress a change in the viscosity of the liquid due to an increase in the temperature of the liquid, and can prevent the high definition of printing from being lowered.

In particular, the liquid discharge device 100 is configured to circulate the liquid using the circulation device 2. If the temperature of the liquid recovered from the outflow pipe portion 15 is high, the temperature of the liquid is high even if the temperature of the liquid drops when passing through the circulation device 2. Therefore, the temperature of the liquid supplied to the inflow pipe portion 14 again becomes high. Therefore, if the liquid is repeatedly circulated between the circulation device 2 and the head device 5, the temperature of the liquid increases each time it passes through the head device 5. However, the liquid discharge head 1 of the present embodiment can suppress an increase in the temperature of the liquid by cooling the liquid passing through the outflow pipe portion 15 with the cooling device 13.

More specifically, for example, the temperature of the liquid flowing in from the inflow pipe portion 14 and the temperature of the liquid flowing out from the outflow pipe portion 15 are set to suitable temperatures based on the viscosity of the suitable liquid. For example, the temperature of the inflow from the inflow pipe portion 14 is set to be constant at 40 ° C. Further, for example, the temperature of the liquid flowing out from the outflow pipe portion 15 is set to 50 ° C. as an upper limit value. Then, the cooling device 13 cools the outflow pipe portion 15 in order to bring the liquid to these set temperatures. As a result, in the configuration of the liquid discharge device 100 in which the liquid is circulated by the circulation device 2, the liquid discharge head 1 can circulate the liquid at a desired temperature.

Further, the cooling device 13 has a configuration in which the cooling plate 51 is brought into contact with the liquid discharge unit 10 to cool the liquid discharge unit 10. Therefore, it is also possible to cool the liquid that becomes hot in the liquid discharge unit 10 with the cooling device 13. Further, since the cooling device 13 can cool the liquid in the liquid discharge unit 10 and further cool the liquid flowing out from the liquid discharge unit 10 to the outflow pipe portion 15, high cooling performance can be ensured.

Further, the cooling device 13 can cool the electronic components and the driver IC 43 by contacting the cooling plate 51 with the heat-generating electronic components and the driver IC 43 mounted on the control board 41. In addition, the cooling device 13 can efficiently cool the driver IC 43 that generates heat by arranging the cooling flow path 52 formed in the cooling plate 51 to pass over the driver IC 43.

Further, the cooling device 13 has a configuration in which a part of the outer surface of the region where the primary side of the cooling flow path 52 exists is brought into contact with the outer surface of the outflow pipe portion 15. With this configuration, the cooling water for cooling the liquid flowing inside the outflow pipe portion 15 becomes low-temperature cooling water before heat exchange with the driver IC 43. Therefore, the cooling device 13 can efficiently cool the liquid flowing through the outflow pipe portion 15.

As described above, according to the liquid discharge head 1 and the liquid discharge device 100 according to the embodiment, the temperature rise of the liquid can be suppressed.

The present invention is not limited to the above-described embodiment as it is, and at the implementation stage, the components can be modified and embodied within a range that does not deviate from the gist thereof. Hereinafter, other embodiments will be illustrated, but the same configurations as those of the above-described embodiments will be designated by the same reference numerals, and detailed description thereof will be omitted.

For example, in the above-described example, the cooling device 13 of the liquid discharge head 1 has described a configuration in which the outer surface of the cooling plate 51 on which the primary side exists is in contact with the outer surface of the outflow pipe portion 15, but the present invention is not limited to this. For example, if the temperature of the cooling water flowing through the cooling flow path 52 is a temperature at which the liquid flowing through the outflow pipe portion 15 can be cooled, the outer surface of the cooling plate 51 where the secondary side of the cooling flow path 52 exists flows out. It may be configured to come into contact with the pipe portion 15.

Further, in the above-described example, the cooling device 13 of the liquid discharge head 1 has described an example in which the cooling plate 51 is separated from the inflow pipe portion 14, but the present invention is not limited to this. Like the head device 5 of the liquid discharge head 1 according to the second embodiment shown in FIG. 10, the cooling plate 51 may be configured to come into contact with the inflow pipe portion 14 in addition to the outflow pipe portion 15. In such a cooling plate 51, a part of the outer surface where the primary side of the cooling flow path 52 exists comes into contact with the outflow pipe portion 15, and a part of the outer surface where the secondary side of the cooling flow path 52 exists comes into contact with the inflow pipe portion 14. Contact.

Such a head device 5 can cool the inflow pipe portion 14 when the temperature of the cooling water flowing on the secondary side of the cooling flow path 52 is set to a temperature lower than the temperature of the liquid flowing through the inflow pipe portion 14. .. Therefore, the temperature of the cooling water flowing through the cooling flow path 52 is lower than the set temperature of the liquid flowing through the inflow pipe portion 14, for example, 40 ° C., and the temperature flowing through the inflow pipe portion 14 is higher than the set temperature. When there is a risk of such a situation, it is more preferable to configure the head device 5 of the liquid discharge head 1 of the second embodiment. According to the liquid discharge head 1 according to the second embodiment, in addition to the liquid passing through the outflow pipe portion 15, the liquid supplied to the liquid discharge portion 10 through the inflow pipe portion 14 is also cooled by the cooling device 13. It becomes possible to do.

Further, in the above-described example, the cooling device 13 of the liquid discharge head 1 has been described so as to have the cooling plate 51 in contact with the outflow pipe portion 15, but the present invention is not limited to this. The cooling plate 51 and the outflow pipe portion 15 may be integrally formed as in the head device 5 of the liquid discharge head 1 according to the third embodiment shown in FIG. For example, the cooling plate 51 and the outflow pipe portion 15 having such a configuration may have a configuration in which a portion of the cooling plate 51 where, for example, the primary side of the cooling flow path 52 exists is adjacent to the outflow pipe portion 15.

The cooling plate 51 in which such an outflow pipe portion 15 is integrally formed is formed, for example, by cutting a metal material or the like to form the outflow pipe portion 15 in a part thereof. Further, the head device 5 may fluidly connect the outflow pipe portion 15 to the second common chamber F when the cooling plate 51 is connected to the liquid discharge portion 10. With such a configuration, in the head device 5 of the liquid discharge head 1 according to the third embodiment, since the cooling plate 51 and the outflow pipe portion 15 are integrated, the inside of the cooling plate 51 and the outflow pipe portion 15 The heat exchange of the liquid flowing through the water can be efficiently performed. Therefore, the cooling device 13 can improve the cooling performance of the liquid passing through the outflow pipe portion 15. Further, since the cooling plate 51 and the outflow pipe portion 15 are integrated in the head device 5, the number of parts can be reduced. In the configuration in which the liquid flowing through the inflow pipe portion 14 is cooled by the cooling plate 51 as in the second embodiment, the cooling plate 51, the outflow pipe portion 15, and the inflow pipe portion 14 are also integrally molded. You may.

Further, in the above-described example, the configuration in which the liquid discharge head 1 has a plurality of head devices 5 has been described, but for example, a plurality of heads such as the liquid discharge head 1 according to the fourth embodiment shown in FIG. A manifold in which the outflow pipe portion 15 of the device 5 is integrally formed may be used. FIG. 12 is a plan view schematically showing the configuration of the head device 5 of the liquid discharge head 1 according to the fourth embodiment. The liquid discharge head 1 according to the fourth embodiment includes a plurality of head devices 5 excluding the outflow pipe portion 15, and a single multi-purpose pipe member 16 which is an assembly of the plurality of outflow pipe portions 15. Then, the liquid discharge head 1 connects one multi-purpose pipe member 16 to a plurality of head devices 5, and brings the cooling plates 51 of the cooling devices 13 of the plurality of head devices 5 into contact with the one multi-purpose pipe member 16. With such a configuration, in addition to the effects of the liquid discharge head 1 of each of the above-described embodiments, the liquid discharge head 1 performs the functions of the plurality of outflow pipe portions 15 with one component (multi-purpose pipe member 16). Therefore, the number of parts of the liquid discharge head 1 can be reduced. Further, since the plurality of cooling plates 51 come into contact with one multi-purpose pipe member 16, the variation in cooling of the outflow pipe portion 15 by the cooling plate 51 is suppressed, and the temperature of the liquid in the plurality of head devices 5 of the liquid discharge head 1 is suppressed. Variation is suppressed. In addition, a plurality of inflow pipe portions 14 may be integrally formed to form a multi-purpose pipe member.

Further, in the above-described example, the liquid discharge head 1 is provided with one inflow pipe portion 14 on one side in the arrangement direction of the plurality of grooves 211 in the X direction of the liquid discharge portion 10, and one outflow pipe portion on the other side. Although the configuration in which 15 is provided has been described, the present invention is not limited to this. For example, the head device 105 of the liquid discharge head 1 according to the fifth embodiment shown in FIG. 13 may have a pair of inflow pipe portions 14 and a pair of outflow pipe portions 15. In the case of the head device 105 having such a configuration, the pair of outflow pipe portions 15 are arranged inside the pair of inflow pipe portions 14 in the X direction, and the pair of outflow pipe portions 15 are arranged on the cooling plate 51 of the cooling device 13. It may be configured to be in contact with each other. Further, when the cooling plate 51 and the pair of outflow pipe portions 15 are integrally formed, the outflow pipe portions 15 may be integrally formed at both ends in the X direction of the cooling plate 51. Further, in the cooling flow path 52, the primary side flow paths are arranged on both sides in the X direction of the cooling plate 51, and the flow paths are merged on the center side of the cooling plate 51, and are secondary to the center side in the X direction of the cooling plate 51. The configuration may be such that the flow path on the side is arranged. The head device 105 used for the liquid discharge head 1 according to the fifth embodiment has the same effect as the head device 5 of each of the above-described embodiments.

Further, in the above-described example, the liquid discharge head 1 is provided with one inflow pipe portion 14 on one side in the arrangement direction of the plurality of grooves 211 in the X direction of the liquid discharge portion 10, and one outflow pipe portion on the other side. Although the configuration in which 15 is provided has been described, the present invention is not limited to this. For example, as in the head device 205 of the liquid discharge head 1 according to the sixth embodiment shown in FIGS. 14 and 15, one inflow pipe portion 14 and one outflow pipe portion 15 are arranged adjacent to each other in the X direction. Alternatively, it may be configured to be provided integrally. As shown in FIGS. 14 and 15, in the present embodiment, a plurality of flexible wiring boards 42 are provided, and two flexible wiring boards 42 are provided in the drawing. Further, as shown in FIGS. 14 and 15, the cooling plate 51 of the present embodiment shows an example of a rectangular shape.

In the case of the head device 205 having such a configuration, the outflow pipe portion 15 is arranged adjacent to the cooling plate 51 of the cooling device 13, and the cooling plate 51 is brought into contact with the outflow pipe portion 15, or the cooling plate is used. The 51 and the outflow pipe portion 15 are integrally molded. Further, the inflow pipe portion 14 and the outflow pipe portion 15 may be in contact with each other or may be separated from each other. The head device 205 used for the liquid discharge head 1 according to the sixth embodiment has the same effect as the head devices 5 and 105 of the above-described embodiments.

Further, when the liquid discharge head 1 according to the fifth embodiment and the liquid discharge head 1 according to the sixth embodiment use a plurality of head devices 105 and 205, the above description is performed instead of the plurality of outflow pipe portions 15. A configuration may be configured in which one multi-purpose pipe member 16 which is an assembly of a plurality of outflow pipe portions 15 is used. Further, in the liquid discharge head 1 according to the fifth embodiment and the liquid discharge head 1 according to the sixth embodiment, the temperature of the cooling water flowing through the cooling flow path 52 is a temperature at which the liquid flowing through the outflow pipe portion 15 can be cooled. If this is the case, the portion of the cooling plate 51 where the secondary side of the cooling flow path 52 exists may be formed in contact with or integrally with the outflow pipe portion 15. In such a configuration, the flow direction of the cooling water in the cooling flow path 52 of the cooling plate 51 may be reversed.

Further, for example, in the above-described example, the liquid discharge head 1 has a configuration having a plurality of head devices 5, but the liquid discharge head 1 is not limited to this, and the liquid discharge head 1 has a configuration including only one head device 5. May be good.

According to at least one embodiment described above, it is possible to provide a liquid discharge head and a liquid discharge device capable of suppressing a temperature rise of the liquid.

Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are also included in the scope of the invention described in the claims and the equivalent scope thereof.

1 ... Liquid discharge head, 2 ... Circulation device, 4 ... Outer case, 5, 105, 205 ... Head device, 10 ... Liquid discharge part, 12 ... Circuit board (board), 13 ... Cooling device, 14 ... Inflow pipe part, 141 ... Inflow flow path, 15 ... Outflow tube section, 151 ... Outflow channel, 16 ... Multi-purpose tube member, 21 ... Actuator, 211 ... Groove, 212 ... Drive element section, 213 ... Electrode, 22 ... Cover plate, 221 ... Notch , 23 ... Flow path cover, 24 ... Nozzle plate, 241 ... Nozzle, 41 ... Control board, 42 ... Flexible wiring board, 43 ... Driver IC, 51 ... Cooling plate, 52 ... Cooling flow path, 521 ... Opening, 522 ... Opening , 55 ... Coolant supply circuit, 100 ... Liquid discharge device, 111 ... Housing, 112 ... Medium supply unit, 113 ... Image forming unit, 114 ... Medium discharge unit, 114a ... Paper discharge tray, 115 ... Conveyor device, 116 ... Control unit, 117 ... Support unit, 118 ... Conveyance belt, 119 ... Support plate, 120 ... Belt roller, 130 ... Head unit, 132 ... Supply tank, 133 ... Connection flow path, 134 ... Circulation pump, 1121 ... Paper feed cassette, 1141 ... Paper discharge tray, 1211-1218 ... Guide plate pair, 1221-1228 ... Transfer roller, 1331 ... Supply flow path, 1332 ... Recovery flow path, A ... Transport path, C ... Air chamber, D ... Pressure chamber, E ... 1st common room, F ... 2nd common room, P ... paper.

Claims (5)

A first common chamber, an actuator constituting a plurality of pressure chambers connected to the first common chamber, and a liquid discharge unit including a second common chamber connected to the plurality of pressure chambers.
The inflow pipe section that supplies the liquid to the first common chamber and
The outflow pipe portion that discharges the liquid from the second common chamber and
A cooling plate that is thermally connected to the outflow pipe portion, and a cooling device that is provided on the cooling plate and includes a cooling flow path through which cooling water passes.
Liquid discharge head. The outflow pipe portion and the cooling plate are integrally formed.
The liquid discharge head according to claim 1, wherein a portion of the cooling plate where the primary side of the cooling flow path exists is adjacent to the outflow pipe portion. The liquid discharge head according to claim 1, wherein the outer surface of the cooling plate on which the primary side of the cooling flow path is arranged comes into contact with the outer surface of the outflow pipe portion. The inflow pipe portion is provided on one side of the liquid discharge portion in the arrangement direction of the plurality of pressure chambers.
The liquid discharge head according to any one of claims 1 to 3, wherein the outflow pipe portion is provided on the other side of the liquid discharge portion in the arrangement direction of the plurality of pressure chambers. A liquid discharge unit including a first common chamber, an actuator constituting a plurality of pressure chambers connected to the first common chamber, and a second common chamber connected to the plurality of pressure chambers, and a liquid in the first common chamber. A cooling stream provided on the inflow pipe portion to be supplied, the outflow pipe portion for discharging the liquid from the second common chamber, the cooling plate thermally connected to the outflow pipe portion, and the cooling plate through which the cooling water passes. A liquid discharge head equipped with a cooling device including a path,
A circulation device connected to the inflow pipe portion and the outflow pipe portion and supplying the liquid to the liquid discharge portion.
A support device that supports the object that discharges the liquid, and
A liquid discharge device equipped with.

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