Liquid discharge head and liquid discharge device

Abstract

To prevent liquid from adhering to the printing medium and liquid ejection device, and to prevent liquid from entering the housing of the liquid ejection head. [Solution] In the operating position, the liquid discharge head has a refrigerant supply section, a refrigerant recovery section, a first liquid connection section, and a second liquid connection section on the upper surface of the liquid discharge unit. An absorbent body is provided on the upper surface of the housing surrounding these sections. The absorbent body has a first opening for the first liquid connection section, a second opening for the refrigerant supply section, a third opening for the refrigerant recovery section, and a fourth opening for the second liquid connection section. When the absorbent body is divided into three regions of equal area in a plan view from the upper surface, it becomes a first region including the first opening, a second region including the second and third openings, and a third region including the fourth opening.

Description

Technical Field

[0001] The present disclosure relates to a liquid ejection head and a liquid ejection device.

Background Art

[0002] In liquid ejection devices used for business applications such as business, commerce, or industry, high durability that enables long-term use is required. Factors that reduce the durability of the liquid ejection head included in the liquid ejection device include, for example, the intrusion of liquid into the head housing. Factors that cause the intrusion of liquid into the head housing include, for example, dripping of liquid from the liquid connection part when detaching the liquid ejection head from the liquid ejection device, and mist during liquid ejection such as ink. When liquid intrudes into the head housing and adheres to, for example, an electric substrate inside, there is a problem that the electric circuit is short-circuited and the liquid ejection head malfunctions.

[0003] In Patent Document 1, a configuration is described in which a seal member that seals the gap of the liquid connection part is provided, and a groove part is further provided in the vicinity thereof, so that ink is guided to the lower part of the head along the groove part.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the configuration described in Patent Document 1, there is a risk that the ink guided to the lower part of the head adheres to the printing medium and the liquid ejection device, resulting in a decrease in the quality of the printed matter or a failure of the liquid ejection device.

[0006] This disclosure aims to suppress the adhesion of liquid to the printing medium and the liquid ejection device, and to suppress the ingress of liquid into the housing of the liquid ejection head. [Means for solving the problem]

[0007] A liquid discharge head according to one aspect of the present disclosure comprises a liquid discharge unit having a discharge element substrate having a discharge element for discharging liquid from a discharge port, a drive element substrate provided with a drive element for driving the discharge element, and a cooling member having a refrigerant flow path through which a refrigerant for cooling the drive element substrate flows, and being arranged in contact with the drive element substrate, and a housing covering the liquid discharge unit, wherein, in the operating position of the liquid discharge head, the upper surface of the liquid discharge unit has a refrigerant supply unit for supplying refrigerant to the refrigerant flow path, a refrigerant recovery unit for recovering refrigerant from the refrigerant flow path, and a unit for supplying at least liquid to the discharge element. A liquid connection section and a second liquid connection section are provided, and in the operating position of the ink ejection head, an absorbent body is provided on the upper surface of the housing that surrounds the refrigerant supply section, the refrigerant recovery section, the first liquid connection section, and the second liquid connection section, and the absorbent body has a first opening for the first liquid connection section to pass through, a second opening for the refrigerant supply section to pass through, a third opening for the refrigerant recovery section to pass through, and a fourth opening for the second liquid connection section to pass through, and when the absorbent body is divided into three regions of the same area in a plan view from the upper surface, it becomes a first region including the first opening, a second region including the second and third openings, and a third region including the fourth opening. [Effects of the Invention]

[0008] According to this disclosure, it is possible to suppress the adhesion of liquid to the printing medium and the liquid ejection device, as well as the ingress of liquid into the housing of the liquid ejection head. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic diagram showing an example of a liquid dispensing device. [Figure 2]This is a perspective view of the liquid dispensing head. [Figure 3] This is a perspective view of the liquid dispensing head. [Figure 4] This is a disassembled perspective view of the liquid dispensing head. [Figure 5] This is a perspective view of the liquid dispensing unit. [Figure 6] This is a plan view of the liquid dispensing head, with the liquid dispensing unit assembled to the support unit, as seen from the dispensing surface side. [Figure 7] This is a cross-sectional view taken along line VII-VII in Figure 6. [Figure 8] This is a cross-sectional view taken from line VIII-VIII in Figure 6. [Figure 9] This diagram shows the connection configuration of the liquid components between the liquid discharge head support unit and the liquid supply unit. [Figure 10] This is a cross-sectional view of the fluid connection between the liquid supply unit and the liquid supply member. [Figure 11] This diagram shows the connection configuration of the liquid flow path in the support unit. [Figure 12] This diagram shows the connection configuration of the liquid flow path in the liquid discharge unit. [Figure 13] This figure shows the fluid connection configuration within the discharge element substrate. [Figure 14] This is a perspective view of a cooling unit for cooling a drive element substrate. [Figure 15] This is an exploded view of the cooling unit. [Figure 16] This is a cross-sectional view from XVI-XVI in Figure 14. [Figure 17] This is a perspective view of the liquid dispensing head with the absorbent material removed. [Figure 18] This is a plan view of the liquid discharge head, seen from the direction of arrow B in Figure 2. [Figure 19] This is a cross-sectional view from XIX-XIX in Figure 18. [Figure 20] This is a cross-sectional view from XIX-XIX in Figure 18. [Figure 21] This is a plan view of the absorber as seen from above. [Figure 22]A diagram showing a liquid chamber through which ink flows and a liquid chamber through which a refrigerant flows. [Figure 23] A diagram showing the relationship between a refrigerant connection portion and a drive element substrate for driving a recording element of a discharge element substrate. [Figure 24] A diagram showing an example of a liquid discharge unit in a liquid discharge head. [Figure 25] An enlarged view of the liquid discharge unit shown in FIG. 24.

Embodiments for Carrying Out the Invention

[0010] Hereinafter, examples of embodiments of the present disclosure will be described with reference to the drawings. However, the following description does not limit the scope of the present disclosure. As an example, in the present embodiment, a method of discharging liquid by driving a piezo element will be described as an example. However, a thermal method in which liquid is discharged by bubbles generated by a heater element and other various liquid discharge methods are also within the scope of application of the present disclosure. That is, the liquid discharge head can be a head having an arbitrary energy generating element configured to generate energy for discharging liquid.

[0011] The liquid discharge device in the embodiment described below can be an inkjet recording device (recording device) in a form that circulates a liquid such as ink between a tank and a liquid discharge head, but other forms may also be used. For example, without circulating the ink, tanks may be provided on the upstream side and the downstream side of the liquid discharge head, respectively, and the ink may be flowed from one tank to the other tank to flow the ink in the pressure chamber. Further, the device according to the present disclosure is not limited to a recording device that discharges ink, and can be a liquid discharge device that discharges an arbitrary liquid.

[0012] <<First Embodiment>> Figure 1 is a schematic diagram showing an example of the liquid ejection device 10 of this embodiment. The liquid ejection device 10 is equipped with a so-called one-pass type liquid ejection head 100 that completes the recording of an image in a predetermined area of ​​the recording medium 20 in a single movement of the recording medium 20 when recording an image in that area. The liquid ejection head 100 has ejection ports arranged over a range corresponding to the entire width of the recording medium 20 (the X direction in Figure 1). The recording medium 20 is transported in the direction of arrow A by the transport unit 11, and recording is performed by the liquid ejection head 100. The liquid ejection head 100 of this embodiment is a liquid ejection head 100 that corresponds to a total of four colors: cyan, magenta, yellow, and black. More specifically, it has two heads for each color. Specifically, it has cyan heads 100Ca and 100Cb, magenta heads 100Ma and 100Mb, yellow heads 100Ya and 100Yb, and black heads 100Ka and 100Kb. In the following, we will focus on describing one of these eight heads. Furthermore, for the sake of simplicity, any one head will be described as the liquid discharge head 100. Note that the liquid discharge head of this disclosure may be of any form and is not limited to the example shown in Figure 1.

[0013] In this embodiment, the direction from which the liquid is discharged (direction of gravity) is defined as the +Z direction, the upstream side of the transport direction of the recording medium 20 is defined as the +Y direction, and the arrangement direction in which the discharge ports are arranged in the head is defined as the +X direction.

[0014] Figure 2 is a perspective view of the liquid dispensing head 100 of this embodiment. Figure 3 is a perspective view of the liquid dispensing head 100 of this embodiment, viewed from a different direction than Figure 2. Figure 4 is an exploded perspective view of the liquid dispensing head 100 of this embodiment. The configuration of the liquid dispensing head 100 will be explained using Figures 2 to 4. As mentioned above, one of the eight heads shown in Figure 1 will be described below as the liquid dispensing head 100.

[0015] As shown in Figure 3, the liquid discharge head 100 is a head in which four liquid discharge element substrates 210 capable of dispensing liquid are arranged in a staggered pattern on a common support member 310. The liquid discharge head 100 is positioned on the main body of the liquid discharge device by a reference member 340. As shown in Figure 2, the upper part of the liquid discharge head 100 is provided with an ink supply unit 511 and an ink recovery unit 512, which are liquid connection parts, and a refrigerant supply unit 611 and a refrigerant recovery unit 612, which are refrigerant connection parts. These liquid connection parts are connected to the main body liquid connection part 13 on the liquid discharge device main body side, and the refrigerant connection part is connected to the main body refrigerant connection part 14 on the liquid discharge device main body side. As a result, refrigerant and liquid such as ink are supplied from the liquid discharge device main body to the liquid discharge head 100. An absorbent body 440 is provided around the liquid connection part and refrigerant connection part of the liquid discharge head 100. Details of the absorbent body 440 will be described later.

[0016] The exterior of the liquid discharge head 100 is provided with a housing 420 and an electrical connection cover member 430 to cover and protect the electrical circuit board and electrical connections. As shown in Figure 4, the liquid discharge head 100 has a support unit 300 including a common support member 310, an electrical wiring board 400, and an electrical wiring board support member 410 that holds the electrical wiring board 400. The liquid discharge head 100 also has a liquid supply unit 500 that supplies liquid to the liquid discharge unit 200 via the support unit 300, and a cooling unit 600 for cooling the drive circuit. The liquid discharge head 100 is equipped with multiple liquid discharge units 200, specifically four liquid discharge units 200. The configuration of each part of the liquid discharge head 100 will be described in detail below.

[0017] Figure 5 is a perspective view of the liquid discharge unit 200. The liquid discharge unit 200 includes a discharge element substrate 210 for discharging liquid and a flow channel member 240 for supplying liquid to the discharge element substrate 210. The liquid discharge unit 200 also includes a drive circuit board 250 that is electrically connected to the discharge element substrate 210, and a support member 230 that is joined to the discharge surface side of the discharge element substrate 210. The support member 230 is joined to the discharge surface side of the discharge element substrate 210 to suppress liquid ingress into the electrical connection between the discharge element substrate 210 and the drive circuit board 250, and to reinforce the discharge element substrate 210. The drive circuit board 250 is provided with a drive element substrate 251 which is equipped with drive elements for driving the recording elements of the discharge element substrate 210.

[0018] Figure 6 is a plan view of the liquid discharge head, with the liquid discharge unit 200 assembled to the support unit 300, as seen from the discharge surface side. Figure 7 is a cross-sectional view taken along line VII-VII in Figure 6. Figure 8 is a cross-sectional view taken along line VIII-VIII in Figure 6. Figure 8 is a cross-sectional view taken along line VIII-VIII in Figure 6, with the liquid discharge unit 200 assembled to the support unit 300 and the other components assembled. As shown in Figures 7 and 8, the flow path member 240 and the liquid supply member 330 are joined to the common support member 310, and each liquid flow path is fluidly connected. The area around the support member 230 is sealed between it and the frame member 320 by a periphery sealing member 360 to suppress liquid ingress. The back surface of the support member 230 (the surface opposite to the discharge port surface) may be sealed by a back surface sealing member 370 for reinforcement. As shown in Figure 6, the common support member 310 has three holes for inserting the reference fixing member 350. The reference fixing member 350 is fixed to these holes, and the reference member 340 is fixed to the reference fixing member 350. The reference fixing member 350 may be an integral part with the common support member 310.

[0019] Figure 9 shows the connection configuration of the liquid component between the support unit 300 and the liquid supply unit 500 of the liquid discharge head 100 according to this embodiment. Figure 9(a) is a perspective view from above. Figure 9(b) is a perspective view from below. The liquid supply unit 500 has an ink supply unit 511 and an ink recovery unit 512, which are liquid connection parts, and is connected to the main body side liquid connection part 13 (Figure 2) of the liquid discharge device body. This configuration allows liquid to be supplied from the supply system of the liquid discharge device body to the liquid discharge head 100, and the liquid that has passed through the liquid discharge head 100 to be recovered to the supply system of the liquid discharge device body. In this way, the liquid can be circulated through the path of the liquid discharge device body and the path of the liquid discharge head 100. Inside the liquid supply unit 500, a filter (not shown) is provided that communicates with each opening of the liquid connection part 501 in order to remove foreign matter from the supplied ink.

[0020] Figure 10 is a cross-sectional view of the fluid connection between the liquid supply unit 500 and the liquid supply member 330. Figure 10 is a cross-sectional view of XX in Figure 9. Liquid flowing in from the liquid discharge device body side through the liquid connection part 501 passes through the communication port 502 and is supplied to the liquid supply member 330. The space between the liquid supply unit 500 and the liquid supply member 330 is sealed by an elastic member 503.

[0021] Figure 11 shows the connection configuration of the liquid flow path in the support unit 300. Figure 12 shows the connection configuration of the liquid flow path in the liquid discharge unit 200. The liquid supply unit 500 and the liquid supply member 330 in the support unit 300 are fluidly connected by a first communication port 331. A flow path for distributing liquid to each liquid discharge unit 200 is formed inside the liquid supply member 330. In this example, a flow path for distributing liquid to four liquid discharge units 200 is formed inside one liquid supply member 330. The liquid supply member 330 and the common support member 310 are fluidly connected by a second communication port 311. The common support member 310 and each liquid discharge unit 200 are fluidly connected by a third communication port 241 of the flow path member 240, as shown in Figure 12. A liquid flow path 242 is formed inside the flow path member 240. The flow path member 240 is fluidly connected to the flow path conversion member 260 via a fourth communication port 221. Figure 13 shows the fluid connection configuration within the discharge element substrate 210. Liquid flowing in from each of the fourth communication ports 221 passes through the common flow path 222 and is supplied to the discharge element substrate 210, where it is discharged from the discharge port 213 by the piezoelectric element 214, which is the discharge element. The discharge element substrate 210 includes a first substrate 2101 which is joined to the flow path conversion member 260, and a second substrate 2102 which forms the discharge port 213.

[0022] Figure 14 is a perspective view of a cooling unit 600 for cooling the drive element substrate 251. Figure 15 is an exploded view of the cooling unit 600. Figure 16 is a cross-sectional view taken along line XVI-XVI in Figure 14. The drive element substrate 251 is located on the drive circuit board 250. Figure 14 shows the drive element substrate 251 covered by the cooling unit 600. As shown in Figure 14, the cooling unit 600 has a refrigerant supply unit 611 and a refrigerant recovery unit 612, which are refrigerant connection parts. The refrigerant supply unit 611 and the refrigerant recovery unit 612 are connected to the refrigerant supply unit 14 (Figure 2) of the liquid discharge device body. As a result, refrigerant is supplied from the refrigerant supply system of the liquid discharge device body to the cooling unit 600, and the refrigerant that has passed through the cooling unit 600 is recovered to the refrigerant supply system of the liquid discharge device body. In this way, the refrigerant can circulate through the path of the liquid discharge device body and the path of the cooling unit 600. As shown in Figure 15, the refrigerant flowing in from the refrigerant supply unit 611 branches through a refrigerant flow path formed between the first refrigerant supply member 610 and the second refrigerant supply member 620. The second refrigerant supply member 620 and the first cooling member 630 are fluidly connected via a seal member 670. The refrigerant that has branched in the second refrigerant supply member 620 circulates in a refrigerant flow path 631 formed between the first cooling member 630 and the second cooling member 640, and flows back into the second refrigerant supply member 620. The refrigerant that has flowed back into the second refrigerant supply member 620 then merges through a refrigerant flow path formed between the first refrigerant supply member 610 and the second refrigerant supply member 620, and flows out from the refrigerant recovery unit 612.

[0023] The cooling unit 600 of this embodiment has four sets of first cooling members 630 and second cooling members 640. The second refrigerant supply member 620 is separated into two cooling systems in the Y direction. Each cooling system is equipped with two sets of first cooling members 630 and second cooling members 640. These two sets are arranged to face each other in the Y direction. In addition, a heat conduction member 650 that abuts against the first cooling member 630 is provided between these two sets in the Y direction.

[0024] In this configuration, the first cooling member 630 is brought into contact with the drive element substrate 251 with a heat conductive member 650 in between, thereby transferring the heat generated during the operation of the drive element substrate 251 to the coolant in the first cooling member 630. To facilitate the transfer of heat generated by the drive element substrate 251, it is preferable to select a material with the highest possible thermal conductivity, such as aluminum, for the first cooling member 630. An elastic member 660 is provided between the two drive circuit boards 250, which ensures that the heat conductive member 650 is securely in close contact with the drive element substrate 251.

[0025] Figure 17 is a perspective view of the liquid discharge head 100 in Figure 2 with the absorbent 440 removed. As described above, the liquid discharge head 100 is provided with an ink supply unit 511 and an ink recovery unit 512, which are liquid connection units, and a refrigerant supply unit 611 and a refrigerant recovery unit 612, which are refrigerant connection units, at the upper vertical (-Z direction). The liquid connection unit and the refrigerant connection unit are fluidly connected to the main body side liquid connection unit 13 and the main body side refrigerant connection unit 14, respectively, thereby supplying ink and refrigerant to the liquid discharge head 100, and the supplied ink and refrigerant are recovered on the main body side. The liquid connection unit and the refrigerant connection unit are collectively referred to as the fluid connection unit.

[0026] When inserting or removing the liquid ejection device 10 from the main body and the fluid connection, ink or refrigerant may leak from the liquid ejection device. When ink or refrigerant leaks, there is a risk that it may adhere to the liquid ejection head 100. In addition, there is a risk that mist from ink ejection may be stirred up and adhere to the liquid ejection head 100. The liquid ejection head 100 is covered by a housing 420 to suppress malfunctions caused by ink or refrigerant leaking from the connection part with the liquid ejection device 10, or ink mist, adhering to the drive circuit board 250 and the electrical wiring board 400.

[0027] The upper part of the housing 420 is provided with recesses 422 that surround the ink supply unit 511, the ink recovery unit 512, the refrigerant supply unit 611, and the refrigerant recovery unit 612. The upper part of the housing 420 also has through holes formed for the ink supply unit 511, the ink recovery unit 512, the refrigerant supply unit 611, and the refrigerant recovery unit 612 to pass through. The absorbent body 440 also has through holes formed for the ink supply unit 511, the ink recovery unit 512, the refrigerant supply unit 611, and the refrigerant recovery unit 612 to pass through.

[0028] In this embodiment, as shown in Figures 2 and 17, the absorbent body 440 is mounted in a recess 422 provided in the housing 420. That is, the absorbent body 440 is mounted in the recess 422 such that the ink supply unit 511, ink recovery unit 512, refrigerant supply unit 611, and refrigerant recovery unit 612 pass through the through-holes formed in the absorbent body 440. As a result, the lower surface of the absorbent body 440 and the upper surface of the recess 422 come into contact. The absorbent body 440 mounted in this manner prevents ink mist and the like from entering the inside of the housing 420 through the gaps between the housing 420 and the ink supply unit 511, ink recovery unit 512, refrigerant supply unit 611, and refrigerant recovery unit 612. In other words, ink or refrigerant leaking from the connection between the liquid discharge head 100 and the liquid discharge device 10, or ink mist and the like, is absorbed by the absorbent body 440. Therefore, the intrusion of ink mist and the like into the inside of the housing 420 can be suppressed.

[0029] Furthermore, by housing the absorbent 440 in the recess 422 provided on the top surface of the housing 420 and allowing the absorbent 440 to hold liquid, the amount of liquid leaking out to the bottom of the liquid discharge head 100 can be suppressed. This prevents damage to the liquid discharge device and contamination of the printing medium.

[0030] In this embodiment, as shown in Figure 17, the ink supply unit 511 and ink recovery unit 512, which are liquid connection parts, have a straight outer diameter. For example, the outer diameter of the liquid connection part is φ6 mm. On the other hand, the refrigerant supply unit 611 and refrigerant recovery unit 612, which are refrigerant connection parts, have a two-stage outer diameter. Specifically, the refrigerant supply unit 611 and refrigerant recovery unit 612 have an outer diameter shape such that the outer diameter on the housing 420 side is larger than the outer diameter on the side that connects to the liquid discharge device 10 main body. For example, the outer diameter of the housing side of the refrigerant connection part is φ5.2 mm, and the outer diameter on the main body side is φ4 mm. Also, the inner diameter of the refrigerant connection part is smaller than the inner diameter of the liquid connection part.

[0031] In this embodiment, the main body side liquid connection part 13 and the main body side refrigerant connection part 14 are made of tubes. That is, tubes are connected to the ends of the liquid connection part and the refrigerant connection part. When attaching the liquid discharge head 100 to the liquid discharge device 10, the tube connection is done manually. Therefore, in order to prevent incorrect insertion of tubes into the liquid connection part and the refrigerant connection part, the outer diameters of the liquid connection part and the refrigerant connection part are made to be different. Specifically, as described above, the outer diameter of the refrigerant connection part is made smaller (i.e., thinner) than the outer diameter of the liquid connection part. If the refrigerant connection part were to have a straight shape like the liquid connection part, with a thin outer diameter on the side that connects to the main body of the liquid discharge device 10, the inner diameter portion would become elongated, resulting in insufficient mold strength for injection molding and increased pressure loss. For this reason, the refrigerant supply part 611 and the refrigerant recovery part 612, which are the refrigerant connection parts in this embodiment, have an outer diameter shape such that the outer diameter on the housing 420 side is larger than the outer diameter on the side that connects to the main body of the liquid discharge device 10. On the other hand, the outer diameters of the ink supply section 511 and the ink recovery section 512, which are liquid connection parts, are sufficiently large, so there is no need for a two-stage configuration, and they are configured in a straight shape.

[0032] Furthermore, it is conceivable that the refrigerant supply unit 611 and the refrigerant recovery unit 612 have an outer diameter shape such that the outer diameter on the housing 420 side is smaller than the outer diameter on the side connected to the liquid discharge device 10 main body. However, in this case, when the absorbent 440 is installed, the gap between the absorbent 440 and the refrigerant connection part becomes relatively larger. In order to prevent liquid from entering the housing 420, the refrigerant connection part of this embodiment has an outer diameter shape such that the outer diameter on the housing 420 side is larger than the outer diameter on the side connected to the liquid discharge device 10 main body, as shown in Figure 17.

[0033] Figure 18 is a plan view of the liquid discharge head 100 as seen from the direction of arrow B in Figure 2. Figures 19 and 20 are cross-sectional views taken along line XIX-XIX in Figure 18. Figure 19 is a cross-sectional view before the absorbent 440 is installed, and Figure 20 is a cross-sectional view after the absorbent is installed.

[0034] The absorbent body 440 has a first opening 441, a second opening 442, a third opening 443, and a fourth opening 444 formed in order from left to right on the paper. The first opening 441 and the fourth opening 444 correspond to the liquid connection parts, and the second opening 442 and the third opening 443 correspond to the refrigerant connection parts. More specifically, the first opening 441, the second opening 442, the third opening 443, and the fourth opening 444 correspond to the ink supply unit 511, the refrigerant supply unit 611, the refrigerant recovery unit 612, and the ink recovery unit 512, respectively. The absorbent body 440 is attached to the liquid discharge head 100 such that the first opening 441, the second opening 442, the third opening 443, and the fourth opening 444 pass through the corresponding liquid connection parts and refrigerant connection parts.

[0035] The absorbent body 440 is configured such that the diameters of the first opening 441, second opening 442, third opening 443, and fourth opening 444 are smaller than the outer diameters of the ink supply unit 511, refrigerant supply unit 611, refrigerant recovery unit 612, and ink recovery unit 512, respectively. As a result, the absorbent body 440 is tightly sealed to the ink supply unit 511, refrigerant supply unit 611, refrigerant recovery unit 612, and ink recovery unit 512. This effectively suppresses the ingress of liquid into the housing 420. As an example, the diameters of the first opening 441 and the fourth opening 444 are φ5.8 mm, and the diameters of the second opening 442 and the third opening 443 are φ5.1 mm.

[0036] In this embodiment, an example has been described in which a recess 422 is formed on the upper part of the housing 420 and the absorbent 440 is attached so as to fit into the recess 422, but the embodiment is not limited to this example. By providing the recess 422, the absorbent 440 is enclosed on all four sides, which makes it easier to suppress the adhesion of ink, etc., from the surroundings toward the inside of the housing 420, but a configuration without the recess 422 is also possible.

[0037] From the standpoint of suppressing ink intrusion, the higher the vertical height of the absorbent material 440, the better. However, the area necessary for the liquid connection and refrigerant connection to connect to the main body tube must be exposed. Therefore, the height of the absorbent material 440 is set to a height that exposes the liquid connection and refrigerant connection to a degree that allows for tube connection.

[0038] Figure 21 is a plan view of the absorber 440 as seen from above. In the plan view of the absorber 440, the region including the first opening 441 is defined as the first region 445, the region including the second opening 442 and the third opening 443 is defined as the second region 446, and the region including the fourth opening 444 is defined as the third region 447. In this embodiment, the boundaries are determined such that when the absorber 440 is viewed from above in the operating position of the liquid discharge head 100, the first region 445, the second region 446, and the third region 447 have the same area. Note that the areas do not need to be exactly the same; it is sufficient that the first region 445, the second region 446, and the third region 447 have approximately equal areas. For example, the area ratio of the first region 445, the second region 446, and the third region 447 may be 3:3:4.

[0039] The method for determining the boundaries of the first region 445 and the second region 446 may be any method, but it shall be the same as the method for determining the boundaries of the second region 446 and the third region 447. For example, the direction in which the openings are aligned in the absorber 440 shall be defined as the first direction. The first direction corresponds to the X direction. The first direction is also the longitudinal direction of the absorber 440. In the first direction, a line extending from the midpoint of the line connecting the center of the first opening 441 and the center of the second opening 442 adjacent to the first opening 441, in the second direction (Y direction) perpendicular to the first direction, shall be defined as the boundary of the first region 445 and the second region 446. Similarly, in the first direction, a line extending from the midpoint of the line connecting the center of the fourth opening 444 and the center of the third opening 443 adjacent to the fourth opening 444, in the second direction (Y direction), shall be defined as the boundary of the second region 446 and the third region 447. Here, an example using the centers of the openings has been explained, but the outer edges may also be used. In any case, it is sufficient if the region of the absorber 440 can be divided such that the region including the first aperture 441 becomes the first region 445, the region including the second aperture 442 and the third aperture 443 becomes the second region 446, and the region including the fourth aperture 444 becomes the third region 447. The second region 446 is located between the first region 445 and the third region 447 in the first direction.

[0040] FIG. 22 is a diagram showing a liquid chamber (flow path) through which ink flows and a liquid chamber (flow path) through which refrigerant flows. In FIG. 22, the ink supply system 580 and the refrigerant supply system 680 are shown side by side so that their sizes can be compared with each other. As shown in FIG. 22, in the present embodiment, the volume of the liquid chamber (flow path) that supplies ink to the discharge element substrate 210 is larger than the volume of the liquid chamber (flow path) that supplies refrigerant to the cooling member constituted by the first cooling member 630 and the second cooling member 640. Further, as shown in FIGS. 17 to 20 and FIG. 22, the outer diameters of the ink supply section 511 and the ink recovery section 512 are larger than the outer diameters of the refrigerant supply section 611 and the refrigerant recovery section 612. In such a case, the amount of liquid leaking out due to the insertion and removal of the fluid connection portion with the liquid ejection device 10 is likely to be relatively larger for ink than for refrigerant.

[0041] Here, in the present embodiment, the first region 445 and the third region 447 of the absorber 440 are arranged outside the absorber 440 in the first direction. Thereby, the region outside the absorber 440 can be expanded, and the volume capable of absorbing ink by the absorber 440 can be increased. For example, the first region 445 and the third region 447 have a protruding region 450 that protrudes into a region outside in the first direction from the ink supply section 511 and the ink recovery section 512. Furthermore, by arranging the positions of the ink supply section 511 and the ink recovery section 512 as far outside as possible in the first direction, it is also possible to expand the region for ink absorption. <�

[0042] Here, as shown in FIG. 21, let the distance between the ink supply section 511 and the refrigerant supply section 611 be a, the distance between the refrigerant supply section 611 and the refrigerant recovery section 612 be b, and the distance between the ink recovery section 512 and the refrigerant recovery section 612 be c. In this case, it is preferable that "b < a" or "b < c". More preferably, it is preferable that "b < a" and "b < c". That is, it is preferable to make the liquid absorption volume of at least one of the first region 445 and the third region 447 larger than the liquid absorption volume of the second region 446. Thereby, it becomes possible to increase the volume capable of absorbing ink, which may have a larger amount of leaked liquid than refrigerant.

[0043] In this embodiment, an example has been described in which the first region 445, the second region 446, and the third region 447 are formed from a single absorbent 440, but the embodiment is not limited to this example. For example, absorbents divided into regions may be used. In this case, for example, the thickness of the absorbents in the first region 445 and the third region 447 may be greater than the thickness of the absorbent in the second region 446. In this way, it is possible to enhance the liquid absorption effect by changing the density, width, and thickness of the absorbent according to the amount of liquid estimated to leak out in each region.

[0044] In this embodiment, the first opening 441, second opening 442, third opening 443, and fourth opening 444 are described as corresponding to the ink supply unit 511, refrigerant supply unit 611, refrigerant recovery unit 612, and ink recovery unit 512, respectively, but this is not limited to this. The supply unit and recovery unit may be reversed. For example, the first opening 441, second opening 442, third opening 443, and fourth opening 444 may correspond to the ink recovery unit, refrigerant recovery unit, refrigerant supply unit, and ink supply unit, respectively. Alternatively, the first opening 441, second opening 442, third opening 443, and fourth opening 444 may correspond to the ink recovery unit, refrigerant supply unit, refrigerant recovery unit, and ink supply unit, respectively.

[0045] Furthermore, although this embodiment describes an example in which the outer diameters of the ink supply unit 511 and the ink recovery unit 512 are larger than the outer diameters of the refrigerant supply unit 611 and the refrigerant recovery unit 612, the embodiment is not limited to this example. This embodiment is similarly applicable in configurations where the amount of liquid leaked when inserting or removing the fluid connection part with the liquid discharge device 10 is likely to be relatively greater for ink than for refrigerant. That is, the outer diameter of at least one of the ink supply unit 511 and the ink recovery unit 512 may be larger than the outer diameters of the refrigerant supply unit 611 and the refrigerant recovery unit 612. Even in this case, the amount of liquid leaked when inserting or removing the fluid connection part is likely to be relatively greater for ink than for refrigerant.

[0046] In this embodiment, an example was described in which the refrigerant connection part is located closer to the center in the first direction, and the liquid connection part is located further out in the first direction. Furthermore, since it is estimated that a larger amount of liquid will leak from the liquid connection part than from the refrigerant connection part, an example was described in which the first region 445, the second region 446, and the third region 447 described above are provided. The reason why the refrigerant connection part is located closer to the center will be explained below.

[0047] Figure 23 shows the relationship between the refrigerant connection section and the drive element substrate 251 for driving the recording element of the discharge element substrate 210. Figure 23 shows the drive element substrate 251 as viewed from the Y direction in Figures 14 and 15. The arrows indicate the flow of the refrigerant. Figure 23(a) shows the relationship described in this embodiment. Figures 23(b) and (c) show comparative examples with configurations different from this embodiment.

[0048] In this embodiment, the liquid discharge head 100 is provided with multiple drive element substrates 251. As described above, the refrigerant flow path is configured to branch midway to cool multiple drive element substrates 251. Figure 23 shows two drive element substrates 251, but as shown in Figures 14 and 15, two more drive element substrates 251 are provided at opposing positions on the opposite side, and the refrigerant flow path is configured to cool four drive element substrates 251. As shown in the configuration of this embodiment in Figure 23(a), when the refrigerant connection is located on the inside, the drive element substrates 251 can be cooled uniformly by the flow of refrigerant. That is, the drive element substrates 251 are arranged substantially symmetrically around the refrigerant connection, and the refrigerant flow path is configured to branch toward the symmetrically arranged drive element substrates 251. Therefore, the refrigerant flowing into the liquid discharge head 100 can cool the drive element substrates 251 uniformly. Let's consider the case where the refrigerant connection is located on the outside, as shown in the comparative example in Figure 23(b). For example, Figure 23(b) shows a comparative example where the positional relationship between the refrigerant connection and the liquid connection is reversed compared to this embodiment. When the refrigerant connection is located on the outside, the flow path arrangement becomes unbalanced. As a result, the cooling effect of each drive element substrate 251 may become uneven. As shown in the comparative example in Figure 23(c), when the refrigerant connection is located on the outside, it is also possible to convert the refrigerant flow path to the inside. In the case of Figure 23(c), it is possible to make the cooling effect uniform, but the flow path becomes more complex, and the liquid discharge head 100 becomes larger. Furthermore, the cooling effect is reduced as the flow path becomes longer.

[0049] Therefore, as shown in Figure 23(a), it is preferable that the refrigerant connection portion be located on the inside. For this reason, in the liquid discharge head 100 of this embodiment, the refrigerant connection portion is located closer to the center in the first direction, and the liquid connection portion is located on the outside in the first direction. Furthermore, since it is estimated that a larger amount of liquid leaks from the liquid connection portion than from the refrigerant connection portion, the first region 445, the second region 446, and the third region 447 described above are provided.

[0050] As described above, this embodiment makes it possible to suppress the adhesion of liquid to the printing medium and the liquid ejection device, as well as the intrusion of liquid into the housing of the liquid ejection head. Specifically, in this embodiment, the absorbent body 440 is arranged to surround the liquid connection part and the refrigerant connection part provided on the upper part of the housing 420 of the liquid ejection head 100. The absorbent body 440 is configured such that the absorption area is larger on the liquid connection part side, where it is estimated that a large amount of liquid will leak out, than on the refrigerant connection part side. Therefore, it is possible to increase the volume that can absorb liquid when a large amount of leakage is likely.

[0051] <<Second Embodiment>> In the first embodiment, an example was described in which an ink supply unit 511 and an ink recovery unit 512 are provided as liquid connection parts. That is, an example was described in which an ink supply unit 511 is provided as the first liquid connection part and an ink recovery unit 512 is provided as the second liquid connection part. In this embodiment, an example is described in which a first ink supply unit, which is the first liquid connection part, and a second ink supply unit, which is the second liquid connection part, are provided as liquid connection parts. That is, an example is described in which the liquid discharge head of this embodiment is not configured to circulate liquid with the liquid discharge device body side. As an example, the ink supply unit 511 described in the first embodiment is used as the first ink supply unit, and the ink recovery unit 512 is used as the second ink supply unit. Even in this case, the basic configuration is the same as the example described in the first embodiment. However, some of the flow path configurations differ from the first embodiment.

[0052] Figure 24 shows an example of the liquid ejection unit 200 in the liquid ejection head of this embodiment. Figure 25 is an enlarged view of the liquid ejection unit 200 shown in Figure 24. The arrows in Figures 24 and 25 indicate the flow of ink. As shown in Figures 24 and 25, in this embodiment, ejection is performed using ink supplied from both the first ink supply unit and the second ink supply unit. As shown in Figures 24 and 25, the ink ejected using the piezoelectric element 214 is the ink supplied from either the first ink supply unit or the second ink supply unit.

[0053] Thus, even in a configuration where the liquid discharge head does not circulate liquid with the liquid discharge device body, as described in the first embodiment, it is possible to suppress the adhesion of liquid to the printing medium and the liquid discharge device, as well as the ingress of liquid into the housing of the liquid discharge head.

[0054] <<Other Embodiments>> The disclosure of this embodiment includes configurations represented by the following examples of liquid dispensing heads and liquid dispensing devices.

[0055] <Configuration 1> A liquid discharge unit comprising: a discharge element substrate having a discharge element for discharging liquid from a discharge port; a drive element substrate provided with a drive element for driving the discharge element; and a cooling member having a refrigerant flow path through which a refrigerant for cooling the drive element substrate flows, and being arranged in contact with the drive element substrate; A housing that covers the liquid dispensing unit, A liquid dispensing head having, In the operating position of the liquid discharge head, the upper surface of the liquid discharge unit is provided with a refrigerant supply unit for supplying refrigerant to the refrigerant flow path, a refrigerant recovery unit for recovering refrigerant from the refrigerant flow path, and a first liquid connection unit and a second liquid connection unit for supplying at least liquid to the discharge element. In the operating position of the liquid discharge head, an absorbent body is provided on the upper surface of the housing, surrounding the refrigerant supply unit, the refrigerant recovery unit, the first liquid connection unit, and the second liquid connection unit. The liquid discharge head is characterized in that the absorbent has a first opening for passing through the first liquid connection part, a second opening for passing through the refrigerant supply part, a third opening for passing through the refrigerant recovery part, and a fourth opening for passing through the second liquid connection part, and when the absorbent is divided into three regions of the same area in a plan view from the top, it becomes a first region including the first opening, a second region including the second and third openings, and a third region including the fourth opening.

[0056] <Configuration 2> The liquid dispensing head according to configuration 1, wherein a recess is provided on the upper surface of the housing, and the lower surface of the absorbent is in contact with the upper surface of the recess.

[0057] <Structure 3> The liquid dispensing head according to configuration 1 or 2, wherein the second region of the absorbent is positioned between the first region and the third region in a plan view of the upper surface of the housing.

[0058] <Structure 4> A liquid dispensing head according to any one of configurations 1 to 3, wherein the liquid absorption volume of at least one of the first region and the third region of the absorbent is greater than the liquid absorption volume of the second region.

[0059] <Composition 5> A liquid discharge head according to any one of configurations 1 to 4, wherein the volume of the liquid chamber that supplies the liquid to the discharge element substrate is greater than the volume of the liquid chamber that supplies the refrigerant to the cooling member.

[0060] <Composition 6> A liquid discharge head according to any one of configurations 1 to 5, wherein the distance between the center of the first liquid connection and the center of the refrigerant supply unit or refrigerant recovery unit adjacent to the first liquid connection, or the distance between the center of the second liquid connection and the center of the refrigerant supply unit or refrigerant recovery unit adjacent to the second liquid connection, is greater than the distance between the center of the refrigerant supply unit and the center of the refrigerant recovery unit.

[0061] <Composition 7> The liquid discharge head according to any one of configurations 1 to 6, wherein the absorbent has a protruding region that, in a plan view of the upper surface of the housing, protrudes to an area outside the first liquid connection portion or the second liquid connection portion.

[0062] <Structure 8> A liquid discharge head according to any one of configurations 1 to 7, wherein the outer diameter of at least one of the first liquid connection portion and the second liquid connection portion is larger than the outer diameter of the refrigerant supply portion and the refrigerant recovery portion.

[0063] <Composition 9> A liquid discharge head according to any one of configurations 1 to 8, wherein the diameter of the first opening of the absorbent is smaller than the outer diameter of the first liquid connection portion.

[0064] <Composition 10> The liquid discharge head according to any one of configurations 1 to 9, wherein the diameter of the hole in the second opening of the absorbent is smaller than the outer diameter of the refrigerant supply unit.

[0065] <Composition 11> The liquid discharge head according to any one of configurations 1 to 10, wherein the diameter of the hole in the third opening of the absorbent is smaller than the outer diameter of the refrigerant recovery section.

[0066] <Composition 12> The liquid discharge head according to any one of configurations 1 to 11, wherein the diameter of the hole in the fourth opening of the absorbent is smaller than the outer diameter of the second liquid connection portion.

[0067] <Composition 13> The liquid discharge head according to any one of configurations 1 to 12, wherein the first liquid connection part is an ink supply part that supplies ink, and the second liquid connection part is an ink recovery part that recovers ink.

[0068] <Composition 14> The liquid discharge head according to any one of configurations 1 to 12, wherein the first liquid connection part is a first ink supply part that supplies ink, and the second liquid connection part is a second ink supply part that supplies ink.

[0069] <Composition 15> Multiple drive element substrates are provided, A liquid discharge head according to any one of configurations 1 to 14, wherein, in a plan view of the upper surface of the housing, the plurality of drive element substrates are arranged symmetrically with respect to the refrigerant supply unit and the refrigerant recovery unit.

[0070] <Composition 16> A liquid discharge unit comprising: a discharge element substrate having a discharge element for discharging liquid from a discharge port; a drive element substrate provided with a drive element for driving the discharge element; and a cooling member having a refrigerant flow path through which a refrigerant for cooling the drive element substrate flows, and being arranged in contact with the drive element substrate; A housing that covers the liquid dispensing unit, A liquid dispensing head having, In the operating position of the liquid discharge head, the upper surface of the liquid discharge unit is provided with a refrigerant supply unit for supplying refrigerant to the refrigerant flow path, a refrigerant recovery unit for recovering refrigerant from the refrigerant flow path, and a first liquid connection unit and a second liquid connection unit for supplying at least liquid to the discharge element. In the operating position of the liquid discharge head, an absorbent body is provided on the upper surface of the housing, surrounding the refrigerant supply unit, the refrigerant recovery unit, the first liquid connection unit, and the second liquid connection unit. The absorbent body has a first opening for passing through the first liquid connection part, a second opening for passing through the refrigerant supply part, a third opening for passing through the refrigerant recovery part, and a fourth opening for passing through the second liquid connection part. When the absorbent body is divided into three regions of equal area in a plan view from the top, it forms a first region including the first opening, a second region including the second and third openings, and a third region including the fourth opening, respectively, and a liquid discharge head. Multiple liquid connection parts on the main body side that are connected to the first liquid connection part and the second liquid connection part, respectively, Multiple refrigerant connection ports on the main body side, which are connected to the refrigerant supply unit and the refrigerant recovery unit, respectively, A liquid dispensing device characterized by having the following features. [Explanation of symbols]

[0071] 100 liquid dispensing heads 200 Liquid Dispensing Unit 420 cabinets 440 absorbent

Claims

1. A liquid discharge unit comprising: a discharge element substrate having a discharge element for discharging liquid from a discharge port; a drive element substrate provided with a drive element for driving the discharge element; and a cooling member having a refrigerant flow path through which a refrigerant for cooling the drive element substrate flows, and being arranged in contact with the drive element substrate; A housing that covers the liquid dispensing unit, A liquid dispensing head having, In the operating position of the liquid discharge head, the upper surface of the liquid discharge unit is provided with a refrigerant supply unit for supplying refrigerant to the refrigerant flow path, a refrigerant recovery unit for recovering refrigerant from the refrigerant flow path, and a first liquid connection unit and a second liquid connection unit for supplying at least liquid to the discharge element. In the operating position of the liquid discharge head, an absorbent body is provided on the upper surface of the housing, surrounding the refrigerant supply unit, the refrigerant recovery unit, the first liquid connection unit, and the second liquid connection unit. The liquid discharge head is characterized in that the absorbent has a first opening for passing through the first liquid connection part, a second opening for passing through the refrigerant supply part, a third opening for passing through the refrigerant recovery part, and a fourth opening for passing through the second liquid connection part, and when the absorbent is divided into three regions of the same area in a plan view from the top surface, it becomes a first region including the first opening, a second region including the second and third openings, and a third region including the fourth opening.

2. The liquid dispensing head according to claim 1, wherein a recess is provided on the upper surface of the housing, and the lower surface of the absorbent is in contact with the upper surface of the recess.

3. The liquid dispensing head according to claim 1, wherein the second region of the absorbent is positioned between the first region and the third region in a plan view of the upper surface of the housing.

4. The liquid discharge head according to claim 1, wherein the liquid absorption volume of at least one of the first region and the third region of the absorbent is greater than the liquid absorption volume of the second region.

5. The liquid discharge head according to claim 1, wherein the volume of the liquid chamber that supplies the liquid to the discharge element substrate is greater than the volume of the liquid chamber that supplies the refrigerant to the cooling member.

6. The liquid discharge head according to claim 1, wherein the distance between the center of the first liquid connection portion and the center of the refrigerant supply portion or the refrigerant recovery portion adjacent to the first liquid connection portion, or the distance between the center of the second liquid connection portion and the center of the refrigerant supply portion or the refrigerant recovery portion adjacent to the second liquid connection portion, is greater than the distance between the center of the refrigerant supply portion and the center of the refrigerant recovery portion.

7. The liquid discharge head according to claim 1, wherein the absorbent has a protruding region that, in a plan view of the upper surface of the housing, protrudes outward from the first liquid connection portion or the second liquid connection portion.

8. The liquid discharge head according to claim 1, wherein the outer diameter of at least one of the first liquid connection portion and the second liquid connection portion is larger than the outer diameter of the refrigerant supply portion and the refrigerant recovery portion.

9. The liquid discharge head according to claim 1, wherein the diameter of the first opening of the absorbent is smaller than the outer diameter of the first liquid connection portion.

10. The liquid discharge head according to claim 1, wherein the diameter of the hole in the second opening of the absorbent is smaller than the outer diameter of the refrigerant supply section.

11. The liquid discharge head according to claim 1, wherein the diameter of the hole in the third opening of the absorbent is smaller than the outer diameter of the refrigerant recovery section.

12. The liquid discharge head according to claim 1, wherein the diameter of the fourth opening of the absorbent is smaller than the outer diameter of the second liquid connection portion.

13. The liquid discharge head according to any one of claims 1 to 12, wherein the first liquid connection part is an ink supply part for supplying ink, and the second liquid connection part is an ink recovery part for recovering ink.

14. The liquid discharge head according to any one of claims 1 to 12, wherein the first liquid connection part is a first ink supply part that supplies ink, and the second liquid connection part is a second ink supply part that supplies ink.

15. Multiple drive element substrates are provided, The liquid discharge head according to any one of claims 1 to 12, wherein, in a plan view of the upper surface of the housing, the plurality of drive element substrates are arranged symmetrically with respect to the refrigerant supply unit and the refrigerant recovery unit.

16. A liquid discharge unit comprising: a discharge element substrate having a discharge element for discharging liquid from a discharge port; a drive element substrate provided with a drive element for driving the discharge element; and a cooling member having a refrigerant flow path through which a refrigerant for cooling the drive element substrate flows, and being arranged in contact with the drive element substrate; A housing that covers the liquid dispensing unit, A liquid dispensing head having, In the operating position of the liquid discharge head, the upper surface of the liquid discharge unit is provided with a refrigerant supply unit for supplying refrigerant to the refrigerant flow path, a refrigerant recovery unit for recovering refrigerant from the refrigerant flow path, and a first liquid connection unit and a second liquid connection unit for supplying at least liquid to the discharge element. In the operating position of the liquid discharge head, an absorbent body is provided on the upper surface of the housing, surrounding the refrigerant supply unit, the refrigerant recovery unit, the first liquid connection unit, and the second liquid connection unit. The absorbent body has a first opening for passing through the first liquid connection part, a second opening for passing through the refrigerant supply part, a third opening for passing through the refrigerant recovery part, and a fourth opening for passing through the second liquid connection part. When the absorbent body is divided into three regions of equal area in a plan view from the top, it forms a first region including the first opening, a second region including the second and third openings, and a third region including the fourth opening, respectively, and a liquid discharge head. Multiple liquid connection parts on the main body side that are connected to the first liquid connection part and the second liquid connection part, respectively, Multiple refrigerant connection ports on the main body side, which are connected to the refrigerant supply unit and the refrigerant recovery unit, respectively, A liquid dispensing device characterized by having the following features.

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