Liquid ejection head and liquid ejection apparatus

Abstract

To eliminate a possibility that temperature increase of a drive circuit is not cooled sufficiently in a recording head including the drive circuit including a switching element.SOLUTION: A liquid jet head includes: a first drive circuit 241A including a switching element which selects a drive element 231 which supplies a drive signal for jetting a liquid from nozzles 218 of multiple drive elements 231; a case 250 defining a first housing part 251A, a space for housing the first drive circuit 241A; and a first gas supply passage 32A which communicates with the first housing part 251A and is used to supply a gas to the first housing part 251A.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a liquid ejection head and a liquid ejection apparatus.

[0002] The present invention relates to a liquid ejection head and a liquid ejection apparatus that eject liquid from nozzles, and more particularly to an ink jet recording head and an ink jet recording apparatus that eject ink as liquid. [Background technology]

[0003] An inkjet recording head (hereinafter simply referred to as a recording head), which is a representative example of a liquid ejection head that ejects liquid droplets, includes, for example, a flow path substrate in which a pressure chamber is formed, and a driving element such as a piezoelectric actuator provided on one side of the flow path substrate, and ejects ink droplets from a nozzle by applying pressure to the pressure chamber through the displacement of this driving element (see, for example, Patent Document 1).

[0004] The multiple drive elements are selectively supplied with power via a drive circuit, typically a drive IC, to be appropriately driven. For example, the drive circuit includes a switching element, and the switching element selects a drive element to which a drive signal is supplied.

[0005] Here, when the printhead has a driving circuit including a switching element, the temperature of the printhead may rise due to heat generation from the driving circuit when the driving element is driven. This temperature rise may cause the printhead to malfunction. In particular, in a large printhead having a relatively large number of nozzles, the heat generated by the driving circuit is large, and the temperature of the printhead is likely to rise, and the temperature of the ink in the printhead rises and the viscosity decreases accordingly. The decrease in the viscosity of the ink affects the ejection characteristics, and there is a risk of the print quality deteriorating. In addition, when the driving circuit heats up during a printing operation and reaches a predetermined temperature, in order to prevent the driving circuit from malfunctioning due to heat, it is necessary to stop the operation of the driving circuit until the driving circuit reaches a predetermined temperature or lower, and the throughput of the printing operation decreases.

[0006] To solve this problem, there are methods that cool the print head and the drive circuit to suppress the temperature rise of the print head. For example, there is a method that sends air toward the inkjet head through a duct to prevent the body of the inkjet head and the circuit board attached to the inkjet head from rising in temperature (see Patent Document 2). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2016-488 A [Patent Document 2] JP 2009-160895 A Summary of the Invention [Problem to be solved by the invention]

[0008] For example, if the drive circuit is attached to the surface of the print head, it is believed that the temperature rise of the print head and the drive circuit can be prevented even with the configuration described in Patent Document 2. However, if the drive circuit is housed in a space inside the print head, there is a risk that the drive circuit cannot be sufficiently cooled by simply sending air toward the print head.

[0009] It should be noted that the above-mentioned problems can occur in ink jet recording heads of any configuration, and are present not only in ink jet recording heads that eject ink, but also in liquid ejection heads that eject liquids other than ink. [Means for solving the problem]

[0010] One aspect of the present invention that solves the above problem is a liquid ejection head characterized by comprising a first drive circuit including a switching element that selects, from a plurality of drive elements, a drive element that supplies a drive signal for ejecting liquid from a nozzle, a case that defines a first storage section that is a space that accommodates the first drive circuit, and a first gas supply path that communicates with the first storage section and supplies gas delivered by an air supply mechanism to the first storage section.

[0011] Another aspect of the present invention is a liquid ejection device comprising the above-mentioned liquid ejection head and an air supply mechanism connected to the first gas supply path and supplying gas to the first gas supply path. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram illustrating a recording apparatus according to a first embodiment of the present invention. [Diagram 2] FIG. 1 is an exploded perspective view showing a schematic configuration of a recording head according to a first embodiment of the present invention. [Diagram 3] FIG. 1 is a top view showing a schematic configuration of a recording head according to a first embodiment of the present invention. [Figure 4] 1 is a cross-sectional view showing a schematic configuration of a recording head according to a first embodiment of the present invention. [Diagram 5] 1 is an enlarged cross-sectional view showing a schematic configuration of a recording head according to a first embodiment of the present invention. [Figure 6] 1 is an enlarged cross-sectional view showing a schematic configuration of a recording head according to a first embodiment of the present invention. [Figure 7] 1 is a cross-sectional view showing a schematic configuration of a recording head according to a first embodiment of the present invention. [Figure 8] 1 is a side view showing a schematic configuration of a recording head according to a first embodiment of the present invention. [Figure 9] 1 is a side view showing a schematic configuration of a recording head according to a first embodiment of the present invention. [Figure 10] 1 is an enlarged cross-sectional view showing a schematic configuration of a recording head according to a first embodiment of the present invention. [Figure 11]1 is an enlarged cross-sectional view showing a schematic configuration of a recording head according to a first embodiment of the present invention. [Figure 12] 1 is an enlarged cross-sectional view showing a schematic configuration of a recording head according to a first embodiment of the present invention. [Figure 13] FIG. 1 is a diagram illustrating a head unit according to a first embodiment of the present invention. [Figure 14] FIG. 11 is a top view showing a schematic configuration of a recording head according to a second embodiment of the present invention. [Figure 15] FIG. 11 is a cross-sectional view showing a schematic configuration of a recording head according to a second embodiment of the present invention. [Figure 16] FIG. 11 is a top view showing a schematic configuration of a recording head according to a third embodiment of the present invention. [Figure 17] FIG. 11 is a cross-sectional view showing a schematic configuration of a recording head according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. However, the following description is a description of one aspect of the present invention, and the configuration of the present invention can be arbitrarily modified within the scope of the invention.

[0014] In each figure, the same members are given the same reference numerals, and duplicated explanations are omitted. In each figure, X, Y, and Z represent three spatial axes that are mutually orthogonal. In this specification, the directions along these axes are defined as the X direction, Y direction, and Z direction, and the direction indicated by the arrow in each figure is defined as the positive (+) direction, and the opposite direction to the arrow is defined as the negative (-) direction. The Z direction indicates the vertical direction, the +Z direction indicates the vertical downward direction, and the -Z direction indicates the vertical upward direction. Furthermore, the three spatial axes X, Y, and Z, which are not limited to the positive and negative directions, are described as the X axis, Y axis, and Z axis.

[0015] (Embodiment 1) FIG. 1 is a diagram illustrating a schematic diagram of an ink jet recording apparatus, which is an example of a liquid ejecting apparatus according to the present invention.

[0016] The inkjet recording device (hereinafter, simply referred to as "recording device") according to the present invention is a printing device that ejects and impacts ink, which is a type of liquid, onto a medium such as printing paper as ink droplets, and prints images, etc., by forming an array of dots on the medium. In addition to recording paper, any material such as a resin film or cloth can be used as the medium.

[0017] 1, the recording device 1 includes a liquid container 2, a control unit 3, a transport mechanism 4, a movement mechanism 5, and a head unit 100 including a plurality of inkjet recording heads (hereinafter also simply referred to as "recording heads") 10, which are an example of a liquid ejection head. Note that the head unit 100 does not necessarily have to include a plurality of recording heads 10, and may include only one recording head 10.

[0018] The liquid container 2 individually stores multiple types (e.g., multiple colors) of ink to be ejected from the recording head 10. Examples of the liquid container 2 include a cartridge that is detachable from the recording device 1, a bag-shaped ink pack made of a flexible film, and an ink tank that can be refilled with ink. Note that the liquid container 2 stores multiple types of ink with different colors, ingredients, etc.

[0019] The control unit 3 includes, for example, a control device such as a CPU (Central Processing Unit) or an FPGA (Field Programmable Gate Array), and a storage device such as a semiconductor memory. The control unit 3 comprehensively controls each element of the recording device 1, i.e., the transport mechanism 4, the moving mechanism 5, the recording head 10, etc., by the control device executing a program stored in the storage device.

[0020] The transport mechanism 4 is controlled by the control unit 3 to transport the medium S in the Y-axis direction, and has a transport roller 4a. That is, the transport mechanism 4 transports the medium S in the Y-axis direction by rotating the transport roller 4a. Note that the transport mechanism 4 that transports the medium S is not limited to one that includes the transport roller 4a, and may transport the medium S by, for example, a belt or a drum.

[0021] The movement mechanism 5 is controlled by the control unit 3 to reciprocate the head unit 100, which includes multiple recording heads 10, in the X-axis direction. Note that the X-axis direction in which the head unit 100 is reciprocated by the movement mechanism 5 intersects with the Y-axis direction in which the medium S is transported.

[0022] Specifically, the movement mechanism 5 of this embodiment includes a conveyor 6 and a conveyor belt 7. The conveyor 6 is a generally box-shaped structure, a so-called carriage, in which the head unit 100 is housed, and is fixed to the conveyor belt 7. The conveyor belt 7 is an endless belt that is installed along the X-axis direction. The conveyor belt 7 rotates under the control of the control unit 3, so that the head unit 100 moves back and forth along the X-axis direction together with the conveyor 6. The conveyor 6 may be configured to carry a liquid container 2 together with the head unit 100.

[0023] Each recording head 10 included in the head unit 100 ejects ink supplied from a liquid container 2 from multiple nozzles onto the medium S. In the recording device 1, the multiple recording heads 10 eject ink onto the medium S in parallel with the transportation of the medium S by the movement mechanism 5 and the repeated reciprocation of the transport body 6, thereby forming a desired image on the surface of the medium S.

[0024] As will be described in detail later, the recording apparatus 1 also includes an air supply mechanism 50 for supplying cooling gas into each recording head 10.

[0025] Next, the configuration of the recording head 10 included in the head unit 100 will be described.

[0026] FIG. 2 is an exploded perspective view showing a schematic configuration of the recording head 10. FIG. 3 is a top view showing a schematic configuration of the recording head 10. Note that the wiring members 239A, 239B and the holder 240 are omitted in FIG. 3. FIG. 4 is a cross-sectional view showing a schematic configuration of the recording head 10, corresponding to the line AA′ in FIG. 3. FIGS. 5 and 6 are enlarged cross-sectional views showing a schematic configuration of the recording head 10, FIG. 5 corresponds to the line AA′ in FIG. 3, and FIG. 6 corresponds to the line BB′ in FIG. 3. FIG. 7 is a cross-sectional view showing a schematic configuration of the recording head 10, corresponding to the line CC′ in FIG. 3. FIGS. 8 and 9 are side views of the first member 300 and the connection unit 320 constituting the supply path member 30.

[0027] As shown in these FIGS. 2 to 9, the recording head 10 includes a head body 20 capable of ejecting ink, which is an example of liquid, and a supply path member 30 fixed to the head body 20. As shown in FIG.

[0028] The head main body 20 includes a flow passage unit 210, an actuator unit 230 having a plurality of piezoelectric actuators 231, and a case 250 capable of housing the actuator unit 230 therein.

[0029] 5 and 6, a flow path to which ink, which is a liquid, is supplied is formed in the flow path unit 210. The flow path unit 210 includes a flow path forming substrate 211, a vibration plate 212, and a nozzle plate 213. The flow path forming substrate 211, the vibration plate 212, and the nozzle plate 213 are layered in the Z-axis direction.

[0030] The flow path forming substrate 211 is made of, for example, a silicon single crystal substrate or the like, and has a plurality of pressure chambers 214 formed therein. In this embodiment, the flow path forming substrate 211 has two pressure chamber rows, each row being configured with a plurality of pressure chambers 214 arranged in the Y axis direction, and shifted in the X axis direction. That is, the flow path forming substrate 211 has two pressure chambers 214 arranged shifted in the X axis direction, and also has a plurality of pressure chambers 214 arranged along the Y axis direction.

[0031] The pressure chambers 214 constituting each pressure chamber row are arranged on a straight line along the Y axis direction so that their positions in the X axis direction are the same. The pressure chambers 214 adjacent to each other in the Y axis direction are partitioned by partition walls 215. The arrangement of the pressure chambers 214 is not particularly limited.

[0032] Furthermore, in this embodiment, the pressure chamber 214 is formed in, for example, a rectangle, with the length in the X-axis direction being longer than the length in the Y-axis direction. Of course, the shape of the pressure chamber 214 in a plan view in the Z-axis direction is not particularly limited, and may be a parallelogram, polygon, circle, oval, or the like. The oval shape referred to here refers to a shape based on a rectangle with semicircular ends at both longitudinal ends, and includes a rounded rectangle, an ellipse, an egg shape, and the like.

[0033] Furthermore, the flow path forming substrate 211 is provided with a manifold 216 for supplying ink to each pressure chamber 214, and individual flow paths 217 connecting each pressure chamber 214 to the manifold 216, at one end side in the X-axis direction of each pressure chamber 214. In this embodiment, the manifold 216 is provided independently for each row of the pressure chambers 214. That is, the flow path forming substrate 211 is provided with a first manifold 216A and a second manifold 216B corresponding to each row of the pressure chambers 214.

[0034] A vibration plate 212 is provided on one side of the flow path forming substrate 211, and a nozzle plate 213 is provided on the other side. That is, the -Z direction side surface of the flow path forming substrate 211 where the pressure chambers 214 are open is sealed with the vibration plate 212, and the +Z direction side surface of the flow path forming substrate 211 is blocked with the nozzle plate 213. A plurality of nozzles 218 corresponding to each pressure chamber 214 are formed in the nozzle plate 213. The nozzles 218 and the pressure chambers 214 communicate with each other via nozzle communication holes 219 provided to penetrate the flow path forming substrate 211 in the Z axis direction.

[0035] The vibration plate 212 is formed of a composite plate including an elastic film 220 made of an elastic material such as a resin film and a support plate 221 made of a metal material for supporting the elastic film 220, and the elastic film 220 is bonded to the flow path forming substrate 211. For example, polyphenylene sulfide (PPS) can be used as the material of the resin film of the elastic film 220. For example, stainless steel (SUS) can be used as the metal material of the support plate 221.

[0036] In the region of the vibration plate 212 facing each pressure chamber 214, an island portion 222 against which a tip end of a piezoelectric actuator 231 described later abuts is formed. In the region of the vibration plate 212 facing the periphery of each pressure chamber 214, a thin portion 223 having a thickness thinner than other regions is formed, and as a result, the island portion 222 is formed inside the thin portion 223. In this embodiment, the thin portion 223 is formed by partially removing the support plate 221 by etching, that is, the thin portion 223 is a region of the vibration plate 212 facing the pressure chamber 214 that is constituted only by the elastic film 220.

[0037] Furthermore, in the region of each manifold 216 of diaphragm 212, that is, facing first manifold 216A and second manifold 216B, support plate 221 is removed by etching, and a compliance section 224 is provided which is substantially composed of elastic membrane 220 alone, similar to thin section 223. When a pressure change occurs within each manifold 216, elastic membrane 220 which constitutes this compliance section 224 deforms to absorb the pressure change, thereby fulfilling the role of always keeping the pressure within each manifold 216 constant.

[0038] 2 etc., the head body 20 includes an actuator unit 230 having a plurality of piezoelectric actuators 231 corresponding to each pressure chamber 214. In this embodiment, since the pressure chambers 214 are provided in two rows in the flow path forming substrate 211, the head body 20 includes, as the actuator unit 230, a first actuator unit 230A and a second actuator unit 230B corresponding to each row.

[0039] The first actuator unit 230A includes a piezoelectric actuator forming member 232A on which a plurality of piezoelectric actuators 231A are integrally formed, and a fixed plate 233A to which the piezoelectric actuator forming member 232A is fixed. Similarly, the second actuator unit 230B includes a piezoelectric actuator forming member 232B on which a plurality of piezoelectric actuators 231B are integrally formed, and a fixed plate 233B to which the piezoelectric actuator forming member 232B is fixed.

[0040] Each of the fixed plate 233A and the fixed plate 233B is a plate-shaped member elongated along the Y-axis direction, and is made of a material having a thermal conductivity of 10.0 W / m·K or more, such as a metal material. The fixed plate 233A in this embodiment is made of stainless steel, but may be made of aluminum, titanium, or the like. The fixed plate 233B may be made of the same material as the fixed plate 233A. In the following description, when there is no need to distinguish between the fixed plate 233A and the fixed plate 233B, they may be simply referred to as the fixed plate 233.

[0041] Since the first actuator unit 230A and the second actuator unit 230B have the same structure, only the first actuator unit 230A will be described here, and a description of the second actuator unit 230B will be omitted.

[0042] 5 and 6, a plurality of piezoelectric actuators 231A are integrally formed on a piezoelectric actuator forming member 232A. That is, a plurality of piezoelectric actuators 231A arranged along the X-axis direction are integrally formed on the piezoelectric actuator forming member 232A.

[0043] This piezoelectric actuator forming member 232A is formed by alternately laminating a piezoelectric body 234, and individual internal electrodes 235 and a common internal electrode 236, which are internal electrodes that constitute the two poles of the piezoelectric actuator 231A. The individual internal electrode 235 constitutes an individual electrode that is electrically independent from the adjacent piezoelectric actuator 231A. The common internal electrode 236 constitutes a common electrode that is electrically common to the adjacent piezoelectric actuator 231A.

[0044] A plurality of slits 237 are formed by, for example, a wire saw on the end side in the +Z direction of each piezoelectric actuator forming member 232A. The piezoelectric actuator forming member 232A is cut into a comb shape by the plurality of slits 237 formed on the end side in the +Z direction. Each portion of the piezoelectric actuator forming member 232A cut by the plurality of slits 237 functions as a piezoelectric actuator 231A, which is an example of a "driving element". In other words, the piezoelectric actuator forming member 232A has a plurality of piezoelectric actuators 231A arranged side by side along the Y-axis direction.

[0045] Further, the piezoelectric actuator forming member 232A is fixed to the fixed plate 233A near the end on the -Z direction side. That is, the piezoelectric actuator forming member 232A is joined to the fixed plate 233A so that the end on the +Z direction where the multiple piezoelectric actuators 231A are formed becomes a free end. Therefore, when a voltage is applied between the individual internal electrodes 235 and the common internal electrode 236 constituting the piezoelectric actuator 231A, the region on the tip side of each piezoelectric actuator 231A that is not joined to the fixed plate 233A vibrates.

[0046] As shown in FIG. 2 and other figures, a wiring member 238A made of, for example, an FPC (Flexible Printed Circuits) is connected to the first actuator unit 230A having such a configuration. The wiring member 238A is connected to each piezoelectric actuator 231A of the first actuator unit 230A. A wiring member 239A made of, for example, an FPC is connected to the wiring member 238A. A print signal or the like is input to the wiring member 238A through the wiring member 239A. The wiring member 239A is held by a holder 240 fixed to the case 250. As shown in FIG. 7 and other figures, a connector 242A is provided at the end of the wiring member 239A on the -Z direction side. The connector 242A is electrically connected to an external signal cable made of, for example, an FFC (Flexible Flat Cable) provided outside the recording head 10, so that the recording head 10 can receive a print signal or the like from the control unit 3.

[0047] The wiring member 238A is equipped with a first driving circuit 241A such as a driving IC. That is, in this embodiment, the wiring member 238A and the first driving circuit 241A configure a COF (Chip On Film). When a print signal is input via the wiring member 239A, the first driving circuit 241A supplies a driving signal to a predetermined piezoelectric actuator 231A. The first driving circuit 241A includes a plurality of switching elements corresponding to each piezoelectric actuator 231A, and when a print signal is input via the wiring member 239A, the first driving circuit 241A selectively applies a voltage to the predetermined piezoelectric actuator 231A by using these switching elements. That is, when a print signal is input, the first driving circuit 241A selectively drives the plurality of piezoelectric actuators 231A.

[0048] Similar to the first actuator unit 230A, the second actuator unit 230B is connected to a wiring member 238B on which a second drive circuit 241B is mounted, and the wiring member 238B is connected to a wiring member 239B. The wiring member 238B and the second drive circuit 241B form a COF.

[0049] 7 and other drawings, wiring member 239B has connector 242B at the end in the -Z direction, similar to wiring member 239A. Connector 242A of wiring member 239A and connector 242B of wiring member 239B may be provided separately and independently, or may be a common connector. Second drive circuit 241B includes multiple switching elements corresponding to each piezoelectric actuator 231B, and when a print signal is input via wiring member 239B, these switching elements selectively apply a voltage to a specific piezoelectric actuator 231B.

[0050] The first driving circuit 241A has an elongated shape along the Y axis, and is in contact with the fixed plate 233A on a surface facing the -X direction. The first driving circuit 241A and the fixed plate 233A may be fixed via thermally conductive grease, adhesive, pressure sensitive adhesive, etc. Similar to the first driving circuit 241A, the second driving circuit 241B has an elongated shape along the Y axis, and is in contact with the fixed plate 233B on a surface facing the +X direction. The second driving circuit 241B and the fixed plate 233B may be fixed via thermally conductive grease, adhesive, pressure sensitive adhesive, etc.

[0051] A case 250 that houses these actuator units 230 is provided on the −Z direction side of the flow passage unit 210. In other words, the case 250 is joined onto the diaphragm 212 that is joined to the flow passage forming substrate 211.

[0052] The case 250 defines a housing section 251 which is a space for housing the actuator unit 230. As described above, the head main body 20 includes the first actuator unit 230A and the second actuator unit 230B. Therefore, the case 250 is provided with a first housing section 251A which is a space for housing the first actuator unit 230A including the first drive circuit 241A, and a second housing section 251B which is a space for housing the second actuator unit 230B including the second drive circuit 241B. The first housing section 251A and the second housing section 251B are provided penetrating the case 250 in the Z-axis direction, and are arranged side by side in the X-axis direction via a partition wall 252.

[0053] The first actuator unit 230A accommodated in the first accommodation portion 251A and the second actuator unit 230B accommodated in the second accommodation portion 251B are fixed to the case 250 in a state in which they are positioned at predetermined positions.

[0054] Further, in this case 250, two liquid introduction paths 253 are formed for supplying ink in the liquid container 2, which is an ink tank or the like, to each manifold 216. Since the flow path forming substrate 211 is provided with the first manifold 216A and the second manifold 216B, the case 250 is provided with, as the liquid introduction paths 253, a first liquid introduction path 253A for supplying ink to the first manifold 216A and a second liquid introduction path 253B for supplying ink to the second manifold 216B.

[0055] The first liquid introduction path 253A and the second liquid introduction path 253B are provided penetrating the case 250 in the Z-axis direction, and one end side thereof communicates with the first manifold 216A and the second manifold 216B. The first liquid introduction path 253A is disposed approximately at the center of the case 250 in the Y-axis direction, and is disposed on the -X direction side of the first storage section 251A in the X-axis direction. On the other hand, the second liquid introduction path 253B is disposed approximately at the center of the case 250 in the Y-axis direction, and is disposed on the +X direction side of the second storage section 251B in the X-axis direction.

[0056] Ink is supplied from the liquid container 2 to the head main body 20 configured as above via the supply path member 30, which will be described below. That is, ink is introduced into the head main body 20 from the liquid container 2 via the supply path member 30 to the first liquid introduction path 253A and the second liquid introduction path 253B. The introduced ink fills the space from the first liquid introduction path 253A and the second liquid introduction path 253B to the nozzles 218. Then, in a state in which the head main body 20 is filled with ink, the recording head 10 selectively drives the piezoelectric actuators 231A, 231B to change the volume of the pressure chambers 214 and eject ink droplets from predetermined nozzles 218.

[0057] 4 etc., includes a first liquid supply path 31A for supplying ink from the liquid container 2 to a first liquid introduction path 253A of the case 250. The supply path member 30 also includes a second liquid supply path 31B for supplying ink from the liquid container 2 to a second liquid introduction path 253B of the case 250.

[0058] 7 and other drawings, the supply path member 30 includes a first gas supply path 32A communicating with the first accommodating portion 251A for supplying gas to the first accommodating portion 251A, and a first gas discharge path 33A communicating with the first accommodating portion 251A for discharging the gas in the first accommodating portion 251A to the outside. The supply path member 30 also includes a second gas supply path 32B communicating with the second accommodating portion 251B for supplying gas to the second accommodating portion 251B, and a second gas discharge path 33B communicating with the second accommodating portion 251B for discharging the gas in the second accommodating portion 251B to the outside.

[0059] More specifically, the supply path member 30 according to this embodiment includes a first member 300, a second member 310, and a connection unit 320.

[0060] In the first member 300, as will be described in more detail below, a portion of the first liquid supply path 31A and the second liquid supply path 31B, a portion of the first gas supply path 32A and the second gas supply path 32B, and a portion of the first gas discharge path 33A and the second gas discharge path 33B are formed.

[0061] 3, the second member 310 is provided between the first member 300 and the case 250 so as to surround a communication portion where the first storage unit 251A and the first gas discharge path 33A communicate with the first storage unit 251A, and a communication portion where the second storage unit 251B and the second gas discharge path 33B communicate with the second storage unit 251B. The second member 310 is fixed to a surface on the -Z direction side of the case 250, and supports the first member 300 and plays a role in regulating the outflow of gas supplied to the first storage unit 251A and the second storage unit 251B via the first gas supply path 32A and the second gas supply path 32B to the outside.

[0062] The connection unit 320 is attached to the -Z direction side of the first member 300, and forms a portion of the first liquid supply path 31A and the second liquid supply path 31B, a portion of the first gas supply path 32A and the second gas supply path 32B, and a portion of the first gas discharge path 33A and the second gas discharge path 33B.

[0063] More specifically, the first member 300 includes a main body 302 on the surface on the -Z direction side, where a mounting portion 301 for mounting a connection unit 320 is provided.

[0064] Here, a connection unit 320 is provided for each actuator unit 230. In this embodiment, the supply path member 30 includes a first connection unit 320A corresponding to the first actuator unit 230A and a second connection unit 320B corresponding to the second actuator unit 230B. For this reason, the main body 302 of the first member 300 is provided with a first mounting portion 301A to which the first connection unit 320A is attached, and a second mounting portion 301B to which the second connection unit 320B is attached.

[0065] The first mounting portion 301A has a recessed shape recessed in the +Z direction from the surface facing the -Z direction of the main body portion 302, and a part of the first connection unit 320A fits into the recess, thereby positioning the first connection unit 320A and the first mounting portion 301A. The second mounting portion 301B has a recessed shape recessed in the +Z direction from the surface facing the -Z direction of the main body portion 302, and a part of the second connection unit 320B fits into the recess, thereby positioning the second connection unit 320B and the second mounting portion 301B.

[0066] 3 and 8, the first connection unit 320A includes a hollow first ink supply needle 321A constituting a part of the first liquid supply path 31A, a first cylindrical portion 323A in which a first gas introduction portion 322A constituting an inlet portion of the first gas supply path 32A is formed, and a second cylindrical portion 323B in which a first gas discharge portion 324A, which is a hole constituting a part of the first gas discharge path 33A, and the first ink supply needle 321A, the first cylindrical portion 323A, and the second cylindrical portion 323B are arranged side by side in the Y-axis direction and integrated. The arrangement direction of these is not particularly limited, but in this embodiment, the first cylindrical portion 323A in which the first gas introduction portion 322A is formed, the first ink supply needle 321A, and the second cylindrical portion 323B in which the first gas discharge portion 324A is formed are arranged in this order from the +Y direction side to the -Y direction side.

[0067] 3 and 9, the second connection unit 320B includes a hollow second ink supply needle 321B constituting a part of the second liquid supply path 31B, a third cylindrical portion 323C in which a second gas introduction portion 322B constituting a part of the second gas supply path 32B is formed, and a fourth cylindrical portion 323D in which a second gas discharge portion 324B constituting a part of the second gas discharge path 33B is formed, and these are arranged side by side in the Y-axis direction and integrated. The arrangement direction of these is not particularly limited, but in this embodiment, the third cylindrical portion 323C in which the second gas introduction portion 322B is formed, the second ink supply needle 321B, and the fourth cylindrical portion 323D in which the second gas discharge portion 324B is formed are arranged in this order from the -Y direction side to the +Y direction side, which is opposite to the arrangement direction in the first connection unit 320A.

[0068] The first connection unit 320A configured in this manner is attached to the first mounting portion 301A provided on the main body portion 302 of the first member 300, and the second connection unit 320B is attached to the second mounting portion 301B provided on the main body portion 302.

[0069] As a result, in the supply path member 30, the first gas introduction part 322A and the second gas discharge part 324B are arranged side by side in the X-axis direction, and the first gas discharge part 324A and the second gas introduction part 322B are arranged side by side (see FIG. 3).

[0070] Between the first mounting portion 301A and the second mounting portion 301B of the main body portion 302, an insertion hole 303 through which the holder 240 holding the wiring members 239A and 239B is inserted is provided penetrating in the Z-axis direction. This insertion hole 303 may be provided with a size that allows at least the holder 240 and the wiring members 239A and 239B to be inserted, but in this embodiment, it is provided with a size that allows the connectors 242A and 242B to be inserted.

[0071] Although not shown, a filter is provided between the first member 300 and the first and second ink supply needles 321A and 321B. The filter is for removing foreign matter and air bubbles contained in the liquid ink, and is provided with a plurality of fine holes. Examples of such filters that can be used include a sheet-like filter in which a plurality of fine holes are formed by finely weaving or knitting metal, resin, or other fibers, and a plate-like member made of metal, resin, or other material having a plurality of fine holes. The filter may be made of nonwoven fabric, and the material is not particularly limited.

[0072] The first member 300 to which the first connection unit 320A and the second connection unit 320B are attached further includes a plurality of protrusions 304 that protrude from the main body 302 in the +Z direction.

[0073] 4, 7 to 9, the first member 300 includes, as protrusions 304 protruding from the main body 302, a first protrusion 304A in which a part of the first liquid supply path 31A is formed, a second protrusion 304B in which a part of the second liquid supply path 31B is formed, a third protrusion 304C in which a part of the first gas supply path 32A is formed, a fourth protrusion 304D in which a part of the second gas supply path 32B is formed, a fifth protrusion 304E in which a part of the first gas discharge path 33A is formed, and a sixth protrusion 304F in which a part of the second gas discharge path 33B is formed. The first member 300 is fixed to the case 250 via the second member 310 with these multiple protrusions 304 in contact with the case 250.

[0074] In order to liquid-tightly connect first liquid supply path 31A of first protruding portion 304A and first liquid introduction path 253A of case 250, an elastic seal member made of elastomer (not shown) may be interposed between first protruding portion 304A and case 250. The same applies to second protruding portion 304B.

[0075] In this embodiment, each of the protrusions 304 protrudes from the main body 302 independently, but they do not necessarily have to be independent. That is, adjacent ones of the protrusions 304 may be integrally formed. Also, the third protrusion 304C, the fourth protrusion 304D, the fifth protrusion 304E, and the sixth protrusion 304F may be arranged so as to leave a gap between them and the case 250 without contacting the case 250.

[0076] As shown in FIG. 4 and FIG. 8, the first protruding portion 304A is provided with a first through hole 305A that constitutes the first liquid supply path 31A to which ink, which is liquid, is supplied from the outside, penetrating in the axial direction. That is, the first protruding portion 304A is provided so as to protrude cylindrically from the main body portion 302. The first through hole 305A is connected to the first liquid introduction path 253A formed in the case 250. The first through hole 305A is provided so as to penetrate the main body portion 302 together with the first protruding portion 304A, and opens to the first mounting portion 301A. The first mounting portion 301A side of the first through hole 305A is connected to the first ink supply needle 321A mounted to the first mounting portion 301A.

[0077] The first ink supply needle 321A is disposed on the -X direction side of the first liquid introduction path 253A in the X axis direction. Therefore, the first protrusion 304A is provided at an incline so that its tip side approaches the center of the supply path member 30 in the X axis direction.

[0078] As shown in FIG. 4, FIG. 9, etc., the second protruding portion 304B is provided with a second through hole 305B that constitutes a second liquid supply path 31B to which ink, which is a liquid, is supplied, penetrating in the axial direction. That is, the second protruding portion 304B is provided so as to protrude cylindrically from the main body portion 302. This second through hole 305B is connected to the second liquid introduction path 253B formed in the case 250. In addition, the second through hole 305B is provided so as to penetrate the main body portion 302 together with the second protruding portion 304B, and opens to the second mounting portion 301B. The second mounting portion 301B side of the second through hole 305B is connected to the second ink supply needle 321B attached to the second mounting portion 301B.

[0079] The second ink supply needle 321B is disposed on the +X side of the second liquid introduction path 253B in the X-axis direction. Therefore, the second protrusion 304B is provided at an incline so that its tip side approaches the center of the supply path member 30 in the X-axis direction.

[0080] As shown in FIG. 7, FIG. 8, etc., the third protrusion 304C is provided with a first supply communication part 306A, which is a hole constituting the first gas supply path 32A that supplies gas to the first storage part 251A, penetrating in its axial direction. That is, the third protrusion 304C is provided so as to protrude in a cylindrical shape from the main body part 302. The first supply communication part 306A is connected to the first storage part 251A formed in the case 250. The first supply communication part 306A is provided so as to penetrate the main body part 302 together with the third protrusion 304C and opens to the first mounting part 301A. The first mounting part 301A side of the first supply communication part 306A is connected to the first gas introduction part 322A formed in the first cylindrical part 323A.

[0081] The first cylindrical portion 323A in which the first gas introduction portion 322A is formed is disposed on the -X direction side of the first accommodation portion 251A in the X axis direction. Therefore, the third protruding portion 304C in which the first supply communication portion 306A is formed is provided at an incline with respect to the Z axis direction, which is the extension direction of the first cylindrical portion 323A in which the first gas introduction portion 322A is formed. In this embodiment, the third protruding portion 304C is provided at an incline so that its tip side approaches the center side of the supply path member 30 in the X axis direction.

[0082] In addition, in this embodiment, the third protrusion 304C extends in the X-axis direction approximately parallel to the first protrusion 304A, etc., in the top view of Figure 3, and the first supply communication portion 306A is connected to the vicinity of the end portion on the +Y direction side of the first accommodating portion 251A in the Y-axis direction.

[0083] The fourth protrusion 304D is provided with a first exhaust communication portion 307A, which is a hole constituting the first gas exhaust passage 33A for exhausting the gas in the first housing portion 251A to the outside, penetrating in its axial direction. That is, the fourth protrusion 304D is provided protruding in a cylindrical shape from the main body portion 302. The first exhaust communication portion 307A is connected to the first housing portion 251A formed in the case 250. The first exhaust communication portion 307A is provided penetrating the main body portion 302 together with the fourth protrusion 304D and opens to the first mounting portion 301A. The first mounting portion 301A side of the first exhaust communication portion 307A is connected to the first gas exhaust portion 324A formed in the second cylindrical portion 323B.

[0084] The second cylindrical portion 323B in which the first gas discharge portion 324A is formed is disposed on the -X direction side of the first accommodation portion 251A in the X axis direction. Therefore, the fourth protruding portion 304D in which the first discharge communicating portion 307A is formed is provided at an incline with respect to the Z axis direction, which is the extension direction of the second cylindrical portion 323B in which the first gas discharge portion 324A is formed. In this embodiment, the fourth protruding portion 304D is provided at an incline so that its tip side approaches the center side of the supply path member 30 in the X axis direction.

[0085] In addition, in this embodiment, the fourth protrusion portion 304D extends in the X-axis direction approximately parallel to the first protrusion portion 304A, etc. in the top view of Figure 3, and the first discharge communication portion 307A is connected to the vicinity of the end portion on the -Y direction side of the first storage portion 251A in the Y-axis direction.

[0086] As shown in Figs. 7 and 9, the fifth protruding portion 304E is provided with a second supply communicating portion 306B, which is a hole constituting the second gas supply path 32B that supplies gas to the second housing portion 251B, penetrating in its axial direction. That is, the fifth protruding portion 304E is provided so as to protrude in a cylindrical shape from the main body portion 302. The second supply communicating portion 306B is connected to the second housing portion 251B formed in the case 250. The second supply communicating portion 306B is provided so as to penetrate the main body portion 302 together with the fifth protruding portion 304E and opens to the second mounting portion 301B. The second mounting portion 301B side of the second supply communicating portion 306B is connected to the second gas introduction portion 322B formed in the third cylindrical portion 323C.

[0087] The third cylindrical portion 323C in which the second gas introduction portion 322B is formed is disposed on the +X direction side of the second accommodation portion 251B in the X axis direction. Therefore, the fifth protruding portion 304E in which the second supply communication portion 306B is formed is provided at an incline with respect to the Z axis direction, which is the extension direction of the third cylindrical portion 323C in which the second gas introduction portion 322B is formed. In this embodiment, the fifth protruding portion 304E is provided at an incline so that its tip side approaches the center side of the supply path member 30 in the X axis direction.

[0088] In addition, in this embodiment, the fifth protrusion 304E extends in the X-axis direction approximately parallel to the second protrusion 304B, etc. in the top view of Figure 3, and the second supply communication portion 306B is connected to the vicinity of the end portion on the -Y direction side of the second accommodating portion 251B in the Y-axis direction.

[0089] The sixth protrusion 304F is provided with a second exhaust communication portion 307B, which is a hole constituting the second gas exhaust passage 33B that exhausts the gas in the second housing portion 251B to the outside, penetrating in its axial direction. That is, the sixth protrusion 304F is provided so as to protrude in a cylindrical shape from the main body portion 302. The second exhaust communication portion 307B is connected to the second housing portion 251B formed in the case 250. The second exhaust communication portion 307B is provided so as to penetrate the main body portion 302 together with the sixth protrusion 304F and opens to the second mounting portion 301B. The second mounting portion 301B side of the second exhaust communication portion 307B is connected to the second gas exhaust portion 324B formed in the fourth cylindrical portion 323D.

[0090] The fourth cylindrical portion 323D in which the second gas discharge portion 324B is formed is disposed on the +X side of the second accommodation portion 251B in the X-axis direction. Therefore, the sixth protruding portion 304F in which the second discharge communicating portion 307B is formed is provided at an incline with respect to the Z-axis direction, which is the extension direction of the fourth cylindrical portion 323D in which the second gas discharge portion 324B is formed. In this embodiment, the sixth protruding portion 304F is provided at an incline so that its tip side approaches the center of the supply path member 30 in the X-axis direction, similar to the fifth protruding portion 304E.

[0091] In addition, in this embodiment, the sixth protrusion 304F extends in the X-axis direction approximately parallel to the second protrusion 304B, etc., in the top view of Figure 3, and the second discharge communication portion 307B is connected to the vicinity of the end portion on the +Y direction side of the second storage portion 251B in the Y-axis direction.

[0092] In the supply path member 30 configured as above, the first ink supply needle 321A and the second ink supply needle 321B are connected to the liquid container 2 via, for example, a supply tube (not shown). Ink from the liquid container 2 is supplied to the first ink supply needle 321A and the second ink supply needle 321B via the supply tube. An adjustment mechanism for adjusting the ink pressure may be provided between the liquid container 2 and the first ink supply needle 321A and the second ink supply needle 321B.

[0093] Further, the first gas introduction part 322A formed in the first cylindrical part 323A and the second gas introduction part 322B formed in the third cylindrical part 323C are connected to an air supply mechanism 50 provided in the recording apparatus 1. That is, the air supply mechanism 50 is connected to the first gas supply path 32A and the second gas supply path 32B of the supply path member 30, and supplies a cooling gas to the first gas supply path 32A and the second gas supply path 32B.

[0094] In this embodiment, the air supply mechanism 50 includes a gas storage section 51 that stores gas. The first gas introduction section 322A and the second gas introduction section 322B are connected to the gas storage section 51 by an air supply tube 52. In other words, the air supply tube 52 extending from the gas storage section 51 is connected to the first cylindrical section 323A and the third cylindrical section 323C, respectively.

[0095] Although not shown, the gas storage section 51 includes a temperature adjustment device for adjusting the temperature of the gas stored therein. The temperature adjustment device includes, for example, a temperature sensor for detecting the temperature of the gas in the gas storage section 51, a cooling mechanism for cooling the temperature in the gas storage section 51, and a control device for driving the cooling mechanism so that the temperature of the gas in the gas storage section 51 becomes a desired temperature based on the temperature detected by the temperature sensor. The air supply mechanism 50 is configured to supply the cooling gas, which has been adjusted to a predetermined temperature in the gas storage section 51, to the first gas introduction section 322A and the second gas introduction section 322B via the air supply tube 52. The control device may be separate from the control unit 3 or may be shared with the control unit 3. The temperature adjustment device may be provided at any position between the gas storage section 51 and the recording head 10, instead of the gas storage section 51. Furthermore, the recording device 1 does not necessarily need to be provided with a temperature adjustment device.

[0096] Moreover, the gas storage section 51 is airtightly connected to the first gas introduction section 322A and the second gas introduction section 322B by the gas supply tube 52. This allows the gas supply mechanism 50 to satisfactorily supply the gas stored in the gas storage section 51 to the first gas introduction section 322A and the second gas introduction section 322B.

[0097] The air supply mechanism 50 according to this embodiment includes an air supply pump 53 provided in the air supply tube 52, and the air supply pump 53 supplies the gas in the gas storage section 51 to the first gas introduction section 322A and the second gas introduction section 322B. The type of gas supplied by the air supply mechanism 50 is not particularly limited, but it is preferable to use, for example, air, or an inert gas such as nitrogen or argon, and in particular, a gas having a water vapor content of 4 g / m 3 It is preferable to use a dry gas having a water vapor content of 3 g / m or less. 3 More preferably, it is 1 g / m or less. 3 It is even more preferable if it is less than this.

[0098] Incidentally, the method of connecting the air supply tube 52 to the first cylindrical portion 323A and the third cylindrical portion 323C is not particularly limited, but for example, they can be connected as follows: Figures 10 to 12 are enlarged cross-sectional views explaining the method of connecting the air supply tube 52 to the first cylindrical portion 323A.

[0099] First, as shown in Fig. 10, the air supply tube 52 is adopted whose outer diameter is slightly smaller than the inner diameter of the first gas introduction part 322A and whose outer diameter is slightly larger than the inner diameter of the O-ring 56 arranged between the first cylindrical part 323A and the main body part 302. Furthermore, a material having rigidity is adopted for the tip of the air supply tube 52, in other words, at least the part of the air supply tube 52 inserted into the O-ring 56. That is, the tip of the air supply tube 52 inserted into the first gas introduction part 322A is press-fitted into the O-ring 56. This allows the air supply tube 52 and the first gas introduction part 322A to be airtightly connected, and the air supply tube 52 to be held by the O-ring 56.

[0100] 11, in the case where the outer diameter of the air supply tube 52 is slightly smaller than the inner diameter of the first gas introduction part 322A and the tip of the air supply tube 52 is made of a flexible material, a small diameter part 325 in which the inner diameter of the first gas introduction part 322A is slightly smaller than the outer diameter of the air supply tube 52 may be provided in a part of the first cylindrical part 323A in the Z-axis direction. By press-fitting the air supply tube 52 into this small diameter part 325, the air supply tube 52 and the first gas introduction part 322A can be airtightly connected.

[0101] In this case, the inner diameter of small diameter portion 325 is preferably formed so as to become narrower toward first member 300. In other words, the inner surface of small diameter portion 325 is preferably formed in a so-called tapered shape. This makes it easier to insert air supply tube 52 into small diameter portion 325.

[0102] 12, the air supply tube 52 may have an inner diameter slightly smaller than the outer diameter of the first cylindrical portion 323A, and the air supply tube 52 may be attached to the outer periphery of the first cylindrical portion 323A. That is, the first cylindrical portion 323A may be press-fitted into the air supply tube 52. Even with this configuration, the air supply tube 52 and the first gas introduction portion 322A can be airtightly connected.

[0103] Moreover, the gas storage section 51 is connected to the first gas discharge section 324A and the second gas discharge section 324B by an exhaust tube 54. The gas storage section 51, the first gas discharge section 324A, and the second gas discharge section 324B are airtightly connected by the exhaust tube 54. As a result, the air supply mechanism 50 sends the gas discharged from the first gas discharge section 324A and the second gas discharge section 324B into the gas storage section 51 via the exhaust tube 54.

[0104] The air supply mechanism 50 according to this embodiment includes an exhaust pump 55 disposed midway through the exhaust tube 54, and the exhaust pump 55 sends the gas exhausted from the first gas exhaust section 324A and the second gas exhaust section 324B into the gas storage section 51.

[0105] The method of connecting the exhaust tube 54 to the second cylindrical portion 323B and the fourth cylindrical portion 323D is not particularly limited, and they may be connected in the same manner as the air supply tube 52 described above.

[0106] In the recording device 1 according to this embodiment, the cooling gas is forcibly circulated in the recording head 10 at a predetermined timing by the air supply mechanism 50. That is, the air supply mechanism 50 supplies the cooling gas into the storage section 251 through the gas supply path 32, as shown by the arrows in Fig. 3, and further exhausts the gas in the storage section 251 to the outside through the gas exhaust path 33.

[0107] This generates an airflow inside each housing section 251, which in turn cools each actuator unit 230 housed in the housing section 251. Furthermore, by directly supplying the cooling gas from the gas supply path 32 to the housing section 251, the actuator units 230 are more effectively cooled. This makes it possible to suppress a rise in temperature of the recording head 10, and to suppress a deterioration in print quality caused by a change in the ejection characteristics due to a decrease in the viscosity of the ink caused by a rise in temperature.

[0108] Here, in each actuator unit 230, a temperature rise is likely to occur in the drive circuit 241 (241A, 241B), and in a configuration in which this drive circuit 241 is housed within the housing portion 251, i.e., inside the recording head 10, a temperature rise in the recording head 10 is particularly likely to occur.

[0109] However, by forcibly circulating the cooling gas inside the storage section 251 with the above configuration, it is possible to effectively suppress the temperature rise of the drive circuit 241. Therefore, it is possible to suppress the temperature rise of the recording head 10 due to the heat generation of the drive circuit 241, etc. This makes it possible to suppress a decrease in throughput regarding the printing operation.

[0110] In this embodiment, the communication portion where the gas supply path 32 and the gas discharge path 33 communicate with the accommodation portion 251 is surrounded by the second member 310 constituting the supply path member 30. This restricts the gas supplied to the accommodation portion 251 via the gas supply path 32 from flowing out to the outside, and allows the cooling gas to be supplied to the accommodation portion 251 more efficiently. This allows the actuator unit 230 including the drive circuit 241 to be more reliably cooled.

[0111] Furthermore, the second member 310 can suppress the intrusion of ink mist, which is generated from the ink ejected from the recording head 10 and floats inside the recording device 1, into the containing section 251. Also, it can suppress temperature changes inside the recording device 1 caused by the cooling gas supplied into the containing section 251 leaking out of the recording head 10. As a result, it is possible to suppress adverse effects on the printing operation caused by this temperature change.

[0112] Incidentally, the gap between the second member 310 and the case 250 may be sealed, but a small gap, for example, a gap of about 0.3 mm may be formed. The presence of such a gap can suppress an excessive increase in pressure inside the storage section 251. On the other hand, with a gap of this size, the amount of gas inside the storage section 251 leaking out to the outside of the recording head 10 is limited, and the temperature change inside the recording device 1 is also suppressed to a sufficiently small value. Also, if the pressure inside the storage section 251 is positive, the intrusion of ink mist can be suppressed even if a small gap is formed between the second member 310 and the case 250.

[0113] Moreover, the air supply mechanism 50 according to the present embodiment circulates the cooling gas. That is, the gas stored in the gas storage section 51 is stored in the storage section 251 via the air supply tube 52 and the gas supply path 32, and then the gas in the storage section 251 is collected in the gas storage section 51 via the gas exhaust path 33 and the exhaust tube 54, and the collected gas is supplied again to the storage section 251. Therefore, it is possible to suppress the mixing of ink mist and foreign matter (e.g., dust such as paper powder) present outside the recording head 10 into the cooling gas. In other words, it is possible to supply gas that is not mixed with foreign matter or ink mist to the storage section 251. Therefore, it is possible to suppress the breakdown of the recording head 10 due to these foreign matter and ink mist.

[0114] In particular, the air supply tube 52 and the gas introduction section 322 are airtightly connected, and the exhaust tube 54 and the gas discharge section 324 are airtightly connected, so that the mixing of ink mist and external foreign matter into the cooling gas can be more reliably suppressed. In addition, the exhaust tube 54 and the gas discharge section 324 are airtightly connected, so that the gas supplied into the storage section 251 can be reduced from being discharged to the outside of the recording head 10 and the space inside the recording device 1, specifically, the space where the recording head 10 performs the recording operation. Therefore, it is possible to suppress the flight curve of the liquid ejected from the nozzle 218 and the change in temperature of the space inside the recording device 1, which are caused by the gas discharged to the space outside the recording head 10.

[0115] The exhaust tube 54 does not necessarily have to be provided, and the gas in the storage section 251 may be discharged to the outside of the recording head 10 via the gas discharge path 33. Furthermore, the gas storage section 51 does not necessarily have to be provided. In that case, however, it is preferable to extend the air supply tube 52 from a region where the floating of ink mist is as small as possible, for example, from a space outside the housing (not shown) of the recording device 1, and connect it to the gas introduction section 322.

[0116] In this embodiment, the first connection unit 320A has a first gas introduction part 322A, a first ink supply needle 321A, and a first gas exhaust part 324A arranged in this order from the +Y side. The second connection unit 320B has a second gas introduction part 322B, a second ink supply needle 321B, and a second gas exhaust part 324B arranged in this order from the -Y side. That is, the gas introduction parts 322, the gas exhaust part 324, and the ink supply needle 321 are arranged side by side along the surface of the fixed plate 233 in the longitudinal direction of the drive circuit 241 on the opposite side of the fixed plate 233 to the drive circuit 241.

[0117] In this embodiment, a fixed plate 233A is provided between the first gas introduction part 322A, the first ink supply needle 321A, and the first gas exhaust part 324A, and the first drive circuit 241A, and since the fixed plate 233A is made of a metal material and is in contact with the first drive circuit 241A, heat from the first drive circuit 241A is easily conducted to the fixed plate 233A. Similarly, a fixed plate 233B is provided between the second gas introduction part 322B, the second ink supply needle 321B, and the second gas exhaust part 324B, and the second drive circuit 241B, and since the fixed plate 233B is made of a metal material and is in contact with the second drive circuit 241B, heat from the second drive circuit 241B is easily conducted to the fixed plate 233B.

[0118] Therefore, by generating a gas flow along the surface of the fixed plate 233 in the longitudinal direction of the drive circuits 241 inside the housing portion 251, it is possible to efficiently cool each drive circuit 241 via the fixed plate 233. Also, by arranging the gas inlet 322, the gas outlet 324, and the ink supply needle 321 in parallel in this manner, it is possible to effectively utilize the space and prevent the recording head 10 from becoming large in the X-axis direction.

[0119] As described above, the first cylindrical portion 323A in which the first gas introduction portion 322A is formed, the second cylindrical portion 323B in which the first ink supply needle 321A and the first gas discharge portion 324A are formed are arranged in this order from the +Y direction side to the -Y direction side. Meanwhile, the third cylindrical portion 323C in which the second gas introduction portion 322B is formed, the second ink supply needle 321B and the fourth cylindrical portion 323D in which the second gas discharge portion 324B is formed are arranged in this order from the -Y direction side to the +Y direction side. The vibration plate 212 that defines the first storage portion 251A to which the first gas introduction portion 322A and the first gas discharge portion 324A are connected, and the second storage portion 251B to which the second gas introduction portion 322B and the second gas discharge portion 324B are connected is common to the first storage portion 251A and the second storage portion 251B.

[0120] In this manner, by arranging the first gas introduction part 322A on one side in the Y-axis direction and the second gas introduction part 322B on the other side in the Y-axis direction, when gas is supplied from the first gas introduction part 322A and the second gas introduction part 322B to the accommodation part 251, it is possible to suppress stress concentration on the vibration plate 212 due to the wind pressure. As a result, it is possible to suppress the vibration plate 212 from peeling off from the case 250. Also, it is possible to reduce variation in the ejection characteristics.

[0121] Incidentally, the head unit 100 is configured by arranging a plurality of such recording heads 10 in parallel. In the head unit 100, the arrangement of the plurality of recording heads 10 is not particularly limited, but it is preferable that they are arranged as follows.

[0122] In each recording head 10, as described above, the first gas introduction section 322A and the second gas exhaust section 324B are arranged on one side in the Y-axis direction, and the first gas exhaust section 324A and the second gas introduction section 322B are arranged side by side on the other side in the Y-axis direction.

[0123] Therefore, in the head unit 100, as shown in FIG. 13, it is preferable that the recording heads 10 are arranged in a so-called staggered pattern so that the first gas introduction section 322A and the second gas introduction section 322B of each adjacent recording head 10 are adjacent to each other, and the first gas exhaust section 324A and the second gas exhaust section 324B are adjacent to each other.

[0124] The first gas introduction part 322A and the second gas introduction part 322B are connected to the gas supply tube 52 by joints 60. Similarly, the first gas discharge part 324A and the second gas discharge part 324B are connected to the exhaust tube 54 by joints 61.

[0125] Since the first gas introduction part 322A and the second gas introduction part 322B are adjacent to each other and therefore arranged in close proximity, the joints 60, 61 connected to the first gas introduction part 322A and the second gas introduction part 322B can be arranged in close proximity to each other. Therefore, the gas supply tube 52 connected to the first gas introduction part 322A and the second gas introduction part 322B can be made common up to the part close to the joint 60. Similarly, since the first gas discharge part 324A and the second gas discharge part 324B are adjacent to each other and therefore arranged in close proximity, the exhaust tube 54 can be made common up to the part close to the joint 61.

[0126] Therefore, it is possible to reduce costs by reducing the amount of the air supply tube 52 and the exhaust tube 54 used. In addition, the air supply tube 52 and the exhaust tube 54 can be easily arranged, and various layouts of the air supply tube 52 and the exhaust tube 54 are possible.

[0127] In addition, in Figure 13, only the air supply tube 52 connected to the closely arranged first gas introduction section 322A and second gas introduction section 322B, and the exhaust tube 54 connected to the closely arranged first gas discharge section 324A and second gas discharge section 324B are shown, but the air supply tube 52 is connected to all of the first gas introduction sections 322A and second gas introduction sections 322B, respectively, and the exhaust tube 54 is connected to all of the first gas discharge sections 324A and second gas discharge sections 324B, respectively.

[0128] (Embodiment 2) Fig. 14 is a top view of the recording head 10 according to the second embodiment, and Fig. 15 is a cross-sectional view corresponding to the line DD' in Fig. 14. Note that the wiring members 239 and the holder 240 are omitted in Fig. 14. In the figure, the same members as those in the first embodiment are denoted by the same reference numerals, and duplicated explanations will be omitted.

[0129] This embodiment is a modification of the fixed plate 233A, the fixed plate 233B, the first gas discharge path 33A and the second gas discharge path 33B, and the rest of the configuration is the same as in the first embodiment.

[0130] As described above, the fixed plate 233A according to the first embodiment contacts the first drive circuit 241A, and the fixed plate 233B contacts the second drive circuit 241B (see FIGS. 3, 4, 5, 7, etc.).

[0131] 14 and 15, the fixed plate 233A according to this embodiment is not in contact with the first drive circuit 241A, and the fixed plate 233B is not in contact with the second drive circuit 241B. In this embodiment, the position of the end portion on the -Z direction side of each fixed plate 233 is located in the +Z direction from the drive circuit 241. That is, the surface of the first drive circuit 241A facing the -Y direction faces the inside of the first accommodation portion 251A, and the surface of the second drive circuit 241B facing the +Y direction faces the inside of the second accommodation portion 251B.

[0132] As described above, the first member 300 of embodiment 1 has a fourth protrusion 304D in which the first discharge communication portion 307A is formed, and a sixth protrusion 304F in which the second discharge communication portion 307B is formed (see FIG. 3, etc.).

[0133] In contrast, as shown in Figures 14 and 15, the first member 300A of this embodiment does not have the fourth protrusion 304D and the sixth protrusion 304F, and the first discharge communication portion 307A and the second discharge communication portion 307B are provided penetrating only the main body portion 302 of the first member 300A in the Z-axis direction.

[0134] Even with this configuration, as shown by the arrows in Fig. 14, a gas flow can be generated along the surface of the first drive circuit 241A in the longitudinal direction, so that the first drive circuit 241A can be cooled efficiently. Also, a gas flow can be generated along the surface of the second drive circuit 241B in the longitudinal direction, so that the second drive circuit 241B can be cooled efficiently.

[0135] Also in this embodiment, the gas in the first storage section 251A is collected in the gas storage section 51 via the first gas discharge path 33A including the first discharge communication section 307A and the first gas discharge section 324A and the exhaust tube 54. Similarly, the gas in the second storage section 251B is collected in the gas storage section 51 via the second gas discharge path 33B including the second discharge communication section 307B and the second gas discharge section 324B and the exhaust tube 54.

[0136] However, the first member 300A does not have the fourth protrusion 304D and the sixth protrusion 304F, and a space 330 exists between the first accommodating portion 251A and the first discharge communication portion 307A, and between the second accommodating portion 251B and the second discharge communication portion 307B.

[0137] Therefore, the gas in the first storage section 251A is discharged to this space 330, and then collected in the gas storage section 51 via the first gas discharge path 33A including the first discharge communication section 307A and the first gas discharge section 324A, and the exhaust tube 54. Similarly, the gas in the second storage section 251B is discharged to this space 330, and then collected in the gas storage section 51 via the second gas discharge path 33B including the second discharge communication section 307B and the second gas discharge section 324B, and the exhaust tube 54.

[0138] In addition, since the fourth protrusion 304D is not provided, as shown by the arrows shown by the dashed line in FIG. 14, a gas flow is also generated from the opening of the first supply communication 306A on the first storage unit 251A side through the space 330 toward the first discharge communication 307A. This gas flow can cool the ink in the first through hole 305A constituting the first liquid supply path 31A, and the decrease in the viscosity of the ink can be further suppressed. In addition, since the sixth protrusion 304F is not provided, as shown by the arrows shown by the dashed line in FIG. 14, a gas flow is also generated from the opening of the second supply communication 306B on the second storage unit 251B side through the space 330 toward the second discharge communication 307B. This gas flow can cool the ink in the second through hole 305B constituting the second liquid supply path 31B, and the decrease in the viscosity of the ink can be further suppressed.

[0139] The second member 310 is provided between the case 250 and the first member 300 so as to surround them, and the space 330 formed between the first accommodation portion 251A and the first exhaust communication portion 307A and between the second accommodation portion 251B and the second exhaust communication portion 307B is substantially blocked by the second member 310. Therefore, it can be said that the space 330 constitutes a part of the first gas discharge path 33A and the second gas discharge path 33B.

[0140] (Embodiment 3) 16 is a top view of a recording head 10 according to embodiment 3. In the drawing, the same members as those in the above-described embodiments are given the same reference numerals, and duplicated explanations will be omitted.

[0141] In the first member 300B according to the present embodiment, the third protruding portion 304C in which the first supply communicating portion 306A is formed and the fifth protruding portion 304E in which the second supply communicating portion 306B is formed are inclined in the Y-axis direction so that their tips approach the center of the supply path member 30, as in the first embodiment. Furthermore, the third protruding portion 304C and the fifth protruding portion 304E of the first member 300B are also inclined in the X-axis direction so that their tips approach the center of the supply path member 30, i.e., the liquid supply path 31 side, as shown in FIG.

[0142] The first driving circuit 241A is disposed on an extension of the first supply communication portion 306A formed on the third protrusion 304C. Similarly, the second driving circuit 241B is disposed on an extension of the second supply communication portion 306B formed on the fifth protrusion 304E.

[0143] With this configuration, when the cooling gas is supplied to the first accommodation portion 251A and the second accommodation portion 251B, the cooling gas is sent near the first drive circuit 241A and the second drive circuit 241B, so that it is possible to more reliably suppress the temperature rise of the first drive circuit 241A and the second drive circuit 241B. Note that even when the drive circuit 241 and the fixed plate 233 are in contact with each other as in the first embodiment, that is, when the fixed plate 233 is interposed between the supply communication portion 306 and the drive circuit 241, if the fixed plate 233 is made of a material of 10.0 W / m·K or more, the heat of the drive circuit 241 is easily conducted to the fixed plate 233, and the same effect is obtained.

[0144] (Other embodiments) Although the embodiment of the present invention has been described above, the present invention is not limited to the above-mentioned embodiment.

[0145] For example, in the above-described embodiment, a configuration was exemplified in which the supply communication section 306 constituting the gas supply path 32 and the exhaust communication section 307 constituting the gas exhaust path 33 are provided in the supply path member 30 at an incline with respect to the Z-axis direction (see FIG. 4). However, these supply communication section 306 and exhaust communication section 307 do not necessarily have to be inclined with respect to the Z-axis direction, and may be extended in a direction parallel to the Z-axis direction and in a direction perpendicular to the Z-axis direction, as shown in FIG. 17.

[0146] 17, supply path member 30A includes a first plate-shaped member 341, a second plate-shaped member 342, and a third plate-shaped member 343 that are stacked in the Z-axis direction, and a connection unit 320 that is attached to first plate-shaped member 341. Note that in FIG. 17, the configuration other than that of supply path member 30A is similar to that of embodiment 1, and first connection unit 320A and second connection unit 320B are mounted on first plate-shaped member 341.

[0147] For example, the first supply communication portion 306A is composed of a first supply through portion 351 provided in correspondence with the first gas introduction portion 322A and penetrating the first plate-shaped member 341 and the second plate-shaped member 342 in the Z-axis direction, a second supply through portion 352 provided in correspondence with the first accommodating portion 251A and penetrating the third plate-shaped member 343 in the Z-axis direction, and a supply groove portion 353 provided on the surface of the third plate-shaped member 343 facing the second plate-shaped member 342 and connecting the first supply through portion 351 and the second supply through portion 352.

[0148] Also, for example, the second exhaust communication portion 307B is composed of a first exhaust through portion 361 provided in correspondence with the second gas discharge portion 324B and penetrating the first plate-shaped member 341 and the second plate-shaped member 342 in the Z-axis direction, a second exhaust through portion 362 provided in correspondence with the second accommodating portion 251B and penetrating the third plate-shaped member 343 in the Z-axis direction, and an exhaust groove portion 363 provided on the surface of the third plate-shaped member 343 facing the second plate-shaped member 342 and connecting the first exhaust through portion 361 and the second exhaust through portion 362.

[0149] Of course, even when the supply path member 30A is configured in this way, the same effects as those of the above-described embodiment can be obtained.

[0150] In the above-described embodiment, the supply path member 30 is formed with the first gas discharge path 33A and the second gas discharge path 33B, but the supply path member 30 may not be formed with the first gas discharge path 33A and the second gas discharge path 33B. In this case, the cooling gas supplied from the gas supply path 32 to the housing portion 251 may be discharged to the outside of the recording head 10 through at least one of the gap between the first member 300 and the second member 310, the gap between the case 250 and the second member 310, and the insertion hole 303. Even with such a configuration, the driving circuit 241 housed inside the recording head 10 can be cooled.

[0151] In the above embodiment, a longitudinal vibration type piezoelectric actuator in which a piezoelectric body and an electrode forming material are alternately laminated to expand and contract in the axial direction is used as the driving element for causing a pressure change in the pressure chamber. However, as long as the recording head has a configuration in which a driving circuit is housed inside, the driving element is not particularly limited. For example, a thin film type in which electrodes and a piezoelectric material are laminated by film formation and lithography, or a pressure film type formed by attaching a green sheet, etc., can be used as the driving element. In addition, as the driving element, a type in which a heating element provided corresponding to each pressure chamber is arranged and droplets are ejected from a nozzle by bubbles generated by the heat of the heating element, or a so-called electrostatic actuator in which static electricity is generated between a vibration plate and an electrode, and the vibration plate is deformed by electrostatic force to eject droplets from a nozzle can also be used.

[0152] In addition, in the above-described embodiment, an inkjet recording device in which a recording head is mounted on a carriage and moves in the main scanning direction is exemplified, but the inkjet recording device is not limited to this configuration. For example, the present invention can also be applied to an inkjet recording device such as a line-type recording device in which the recording head is fixed and printing is performed simply by moving a recording sheet such as paper in the sub-scanning direction.

[0153] In the above embodiment, an ink jet recording head is used as an example of a liquid jet head, and an ink jet recording device is used as an example of a liquid jet device. However, the present invention is intended to be applied to a wide range of liquid jet heads and liquid jet devices in general, and can of course be applied to liquid jet heads and liquid jet devices that jet liquids other than ink. Examples of other liquid jet heads include various recording heads used in image recording devices such as printers, color material jet heads used in manufacturing color filters for liquid crystal displays, electrode material jet heads used in forming electrodes for organic EL displays, FEDs (field emission displays), and bioorganic material jet heads used in biochip manufacturing. The present invention can also be applied to liquid jet devices equipped with such liquid jet heads. [Explanation of symbols]

[0154] 1...recording device, 2...liquid container, 3...control unit, 4...transport mechanism, 4a...transport roller, 5...movement mechanism, 6...transport body, 7...transport belt, 10...recording head, 20...head body, 30, 30A...supply path member, 31...liquid supply path, 32...gas supply path, 33...gas exhaust path, 50...air supply mechanism, 51...gas storage section, 52...air supply tube, 53...air supply pump, 54...exhaust tube, 55...exhaust pump, 56...O-ring, 60, 61...connection 100: head unit, 210: flow passage unit, 211: flow passage forming substrate, 212: vibration plate, 213: nozzle plate, 214: pressure chamber, 215: partition wall, 216: manifold, 217: individual flow passage, 218: nozzle, 219: nozzle communication hole, 220: elastic membrane, 221: support plate, 222: island portion, 223: thin portion, 224: compliance portion, 230: actuator unit, 231: piezoelectric actuator, 23 2...Piezoelectric actuator forming member, 233...Fixed plate, 234...Piezoelectric body, 235...Individual internal electrode, 236...Common internal electrode, 237...Slit, 238...Wiring member, 239...Wiring member, 240...Holder, 241...Drive circuit, 250...Case, 251...Storage section, 252...Partition wall, 253...Liquid introduction path, 300...First member, 301...Mounting section, 302...Main body, 303...Insertion hole, 304...Protruding section, 305...Through hole, 306...Supply connection passage portion, 307...exhaust communication portion, 310...second member, 320...connection unit, 321...ink supply needle, 322...gas introduction portion, 323...cylindrical portion, 324...gas exhaust portion, 325...small diameter portion, 330...space, 341...first plate-shaped member, 342...second plate-shaped member, 343...third plate-shaped member, 351...first supply through portion, 352...second supply through portion, 353...supply groove portion, 361...first exhaust through portion, 362...second exhaust through portion, 363...exhaust groove portion, S...medium

Claims

1. a first drive circuit including a switching element that selects a drive element to which a drive signal for ejecting liquid from a nozzle is supplied from among the plurality of drive elements; a case defining a first housing portion that is a space for housing the first drive circuit; a first gas supply passage communicating with the first storage portion and for supplying a gas to the first storage portion; Equipped with A liquid jet head comprising:

2. a first gas exhaust passage communicating with the first storage portion for exhausting gas in the first storage portion to the outside; The liquid jet head according to claim 1 .

3. A first liquid supply passage through which liquid is supplied from an external source is provided, the first gas supply path, the first liquid supply path, and the first gas discharge path are arranged in this order along a longitudinal direction of the first drive circuit. The liquid jet head according to claim 2 .

4. a second drive circuit including a switching element that selects a drive element to which a drive signal for ejecting liquid from a nozzle is supplied from among the plurality of drive elements; the case defines a second housing portion that is a space that houses the second drive circuit and is disposed between the first housing portion and a partition wall therebetween; a second gas supply passage communicating with the second storage portion and for supplying gas from the outside to the second storage portion; a second gas exhaust passage communicating with the second storage portion and configured to exhaust gas within the second storage portion to the outside; a second liquid supply path to which liquid is supplied from the outside; Equipped with a direction in which the second gas supply path, the second liquid supply path, and the second gas discharge path are arranged is opposite to a direction in which the first gas supply path, the first liquid supply path, and the first gas discharge path are arranged. The liquid jet head according to claim 3 .

5. A vibration plate is provided to define the first housing portion and the second housing portion and is common to the first housing portion and the second housing portion.

5. The liquid jet head according to claim 4.

6. a first member fixed to the case to form at least a portion of the first gas supply path; a second member disposed between the first member and the case so as to surround the first storage portion and a communication portion that communicates the first gas supply path with the first storage portion; Equipped with 6. The liquid jet head according to claim 1, wherein the liquid jet head is a liquid jet head.

7. the first gas supply passage includes a first gas introduction portion constituting an inlet portion through which gas is introduced from the outside, and a first supply communication portion connecting the first gas introduction portion and the first storage portion, The first supply communication portion is provided at an angle with respect to an extension direction of the first gas introduction portion, The first drive circuit is disposed on an extension line of the first supply communication portion.

7. The liquid jet head according to claim 1, wherein the liquid jet head is a liquid jet head.

8. A liquid jet head according to any one of claims 1 to 7, a gas supply mechanism connected to the first gas supply path and configured to supply gas to the first gas supply path; A liquid ejection apparatus comprising:

9. The gas supply mechanism has a gas storage section that stores the gas to be supplied to the first gas supply path. The liquid ejecting apparatus according to claim 8 .

10. The gas storage section and the first gas supply path are airtightly connected. The liquid ejection apparatus according to claim 9 .

11. the liquid ejection head includes a first gas exhaust passage that is in communication with the first container and that exhausts gas from within the first container to the outside; The gas supply mechanism is connected to the first gas exhaust path together with the first gas supply path, The gas storage section stores the gas to be delivered to the first gas supply path and the gas discharged from the first storage section through the first gas discharge path. The liquid ejecting apparatus according to claim 9 or 10.

12. The first gas discharge path and the gas storage section are airtightly connected. The liquid ejection apparatus according to claim 11 .

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