Liquid jet head, and liquid jet device

Abstract

To provide a liquid jet head and a liquid jet device which can easily align a plurality of head modules.SOLUTION: A liquid jet head includes a plurality of head modules for jetting liquid in a first direction, and a metal holder to which the plurality of head modules are detachably fixed, wherein each of the plurality of head modules has a flow channel opening formation member which defines a flow channel therein, has a first positioning part and is made of metal, the holder has a plurality of second positioning parts which are press-fit into each of the plurality of first positioning parts, and thereby position each of the plurality of head modules with respect to the holder, and a flow channel opening for being flow-channel connected to the head module formed on the holder, and a flow channel opening for being flow-channel connected to the holder formed on the flow channel opening formation member of the head module overlap each other when viewed in a direction at which one of the first positioning part and the second positioning part is press-fit into the other positioning part.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a liquid ejection head and a liquid ejection apparatus. [Background technology]

[0002] 2. Description of the Related Art Liquid ejection apparatuses equipped with liquid ejection heads that eject liquid such as ink onto a medium such as printing paper have been proposed.

[0003] The liquid jet head described in Patent Document 1 has a plurality of head chips (head modules), a fixing plate, and a holder. The plurality of head chips are housed in a space surrounded by the fixing plate and the holder. The plurality of head chips are aligned with the fixing plate and fixed with an adhesive. The fixing plate is also fixed to the holder with an adhesive. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-42753 Summary of the Invention [Problem to be solved by the invention]

[0005] When some of the head modules included in a liquid jet head malfunction, there is a demand for repairing the liquid jet head by removing only the malfunctioning head module and replacing it with a new head module. However, in conventional documents, when attempting to remove the head module from the holder, it is necessary to remove the fixing plate from the holder. This raises the risk of misalignment between the multiple head modules relative to the fixing plate. Therefore, when repairing the liquid jet head by replacing some of the head modules included in a single liquid jet head, it is desirable to be able to easily align the multiple head modules. [Means for solving the problem]

[0006] A liquid ejection head according to one aspect of the present disclosure comprises a plurality of head modules that eject liquid in a first direction, and a metal holder to which the plurality of head modules are removably fixed, each of the plurality of head modules having a metal flow path opening forming member that defines a flow path therein and has a first positioning portion, the holder has a plurality of second positioning portions that position each of the plurality of head modules relative to the holder by being pressed into or attached to each of the plurality of first positioning portions, and the flow path opening formed in the holder for connecting a flow path to the head module and the flow path opening formed in the flow path opening forming member of the head module for connecting a flow path to the holder overlap when viewed in the direction of pressing one of the first positioning portion and the second positioning portion into the other.

[0007] A liquid ejection apparatus according to an aspect of the present disclosure includes a plurality of the liquid ejection heads and a unit base that holds the plurality of liquid ejection heads. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic diagram illustrating an example of the configuration of a liquid ejecting apparatus according to a first embodiment. [Figure 2] FIG. 2 is a plan view showing the liquid jet unit shown in FIG. [Figure 3] 3 is a cross-sectional view of the liquid jet head shown in FIG. 2 as seen in a direction along the X axis. [Figure 4] 3 is a cross-sectional view of the liquid jet head shown in FIG. 2 as viewed in the direction along the Y axis. [Figure 5] FIG. 4 is a bottom view of the liquid jet head shown in FIG. [Figure 6] FIG. 4 is a cross-sectional view of a chip included in the head module shown in FIG. [Figure 7] 5 is a top view of a flow path opening forming member included in the head module shown in FIG. 4. FIG. [Figure 8]5 is a bottom view showing the holder and the relay board shown in FIG. 4. FIG. [Figure 9] FIG. 5 is a top view of the holder shown in FIG. 4. [Figure 10] FIG. 5 is a plan view of the lower part of the holder shown in FIG. 4. [Figure 11] FIG. 5 is a top view of the sealing member shown in FIG. [Figure 12] FIG. 5 is a top view of the support member shown in FIG. [Figure 13] 10 is a cross-sectional view of a portion of a liquid jet head according to a first modified example. [Figure 14] FIG. 10 is a cross-sectional view of a portion of a liquid jet head according to a second modified example. [Figure 15] 10 is a cross-sectional view of a portion of a liquid jet head according to a third modified example. [Figure 16] FIG. 10 is a cross-sectional view of a portion of a liquid jet head according to a fourth modified example. [Figure 17] FIG. 13 is a cross-sectional view of a portion of a liquid jet head according to a fifth modified example. [Figure 18] 13 is a cross-sectional view of a portion of a liquid jet head according to a seventh modified example. [Figure 19] FIG. 13 is a top view of a liquid jet head according to a seventh modified example. [Figure 20] 13 is a cross-sectional view of a portion of a liquid jet head according to an eighth modified example. FIG. [Figure 21] FIG. 13 is a top view of a liquid jet head according to an eighth modified example. [Figure 22] 13 is a cross-sectional view of a portion of a liquid jet head according to a ninth modified example. [Figure 23] FIG. 20 is a cross-sectional view showing a sealing member and its vicinity according to a tenth modified example. [Figure 24] FIG. 23 is a cross-sectional view of a portion of a liquid jet head according to a tenth modified example. [Figure 25] FIG. 20 is a cross-sectional view showing a sealing member and its vicinity in an eleventh modified example. DETAILED DESCRIPTION OF THE INVENTION

[0009] Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. The dimensions and scale of each part in the drawings may differ from the actual dimensions, and some parts are shown schematically to facilitate understanding. The scope of the present invention is not limited to these embodiments unless otherwise specified in the following description to limit the present invention. Furthermore, the term "element β on element γ" is not limited to a configuration in which element γ and element β are in direct contact with each other, but also includes a configuration in which element γ and element β are not in direct contact with each other. The term "element γ and element β are equal" means that element γ and element β are substantially equal, and includes measurement errors, manufacturing errors, and the like. The term "element γ and element β are the same" means that element γ and element β are substantially equal, and includes measurement errors, manufacturing errors, and the like.

[0010] 1. First embodiment 1-1. Overall configuration of the liquid ejection device 100 FIG. 1 is a schematic diagram illustrating the configuration of a liquid ejection device 100 according to a first embodiment. For ease of explanation, the following description will appropriately use mutually perpendicular X, Y, and Z axes. A direction along the X axis will be referred to as the X1 direction, and a direction opposite to the X1 direction will be referred to as the X2 direction. Similarly, a direction along the Y axis will be referred to as the Y1 direction, and a direction opposite to the Y1 direction will be referred to as the Y2 direction. A direction along the Z axis will be referred to as the Z1 direction, and a direction opposite to the Z1 direction will be referred to as the Z2 direction. The Z1 direction corresponds to the "first direction." The Z2 direction corresponds to the "second direction opposite to the first direction." The Z1 direction relative to a certain point is referred to as "downward," and the Z2 direction from a certain point is referred to as "upward." Viewing in the Z1 or Z2 direction is referred to as a "planar view."

[0011] As shown in FIG. 1, the liquid ejecting device 100 includes a liquid storage section 9, a control unit 91, a conveying section 92, a head unit 10, and a movement mechanism 40.

[0012] The liquid storage unit 9 is a container that stores ink. Specific examples of the liquid storage unit 9 include a cartridge that is detachable from the liquid ejection device 100, a bag-shaped ink pack made of flexible film, and an ink tank that can be refilled with ink. The type of ink stored in the liquid storage unit 9 is not particularly limited and can be any type.

[0013] The control unit 91 controls the operation of each element of the liquid ejection device 100. The control unit 91 includes, for example, a processing circuit such as a CPU (Central Processing Unit) or an FPGA (Field Programmable Gate Array) and a storage circuit such as a semiconductor memory, and controls the operation of each element of the liquid ejection device 100.

[0014] The transport unit 92 transports the medium 90 in a direction DM under the control of the control unit 91. In this embodiment, the direction DM is the Y1 direction. In the example shown in FIG. 1, the transport unit 92 includes a long transport roller along the X axis and a motor that rotates the transport roller. Note that the transport unit 92 is not limited to a configuration using a transport roller, and may be configured, for example, to use a drum or endless belt that transports the medium 90 while adsorbing it to its outer peripheral surface using electrostatic force or the like.

[0015] The movement mechanism 40 has a conveyor belt to which the unit base 11 of the head unit 10 is fixed, and moves the head unit 10 back and forth in the X1 direction and the X2 direction under the control of a control unit 91. Under the control of the control unit 91, the head unit 10 ejects ink supplied from a liquid storage section 9 from each of a plurality of nozzles N onto the medium 90 in the Z1 direction. The ejection of ink from the head unit 10 is performed in parallel with the movement of the head unit 10 by the movement mechanism 40, thereby forming an ink image on the surface of the medium 90.

[0016] The number and arrangement of the multiple liquid jet heads 1 included in the head unit 10 are not limited to the example shown in Fig. 1 and are arbitrary. Furthermore, if the head unit 10 is configured to be able to circulate ink, the head unit 10 may be connected to the liquid storage section 9 via a circulation mechanism for circulating the ink within the head unit 10.

[0017] 1-2. Head unit 10 Fig. 2 is a plan view showing the head unit 10 shown in Fig. 1. As shown in Fig. 2, the head unit 10 includes a unit base 11 and a plurality of liquid jet heads 1. The plurality of liquid jet heads 1 are fixed to the unit base 11. The unit base 11 is a member that holds the plurality of liquid jet heads 1. In the illustrated example, the number of liquid jet heads 1 relative to the unit base 11 is not particularly limited, and may be any number equal to or greater than two.

[0018] The unit base 11 is, for example, a plate-like member whose thickness direction is along the Z axis. A recess 111 is provided in the unit base 11. The recess 111 is a depression provided in the unit base 11. A plurality of through holes 11H are provided in the bottom surface of the recess 111. The planar shape of each through hole 11H is, for example, a rectangle. One through hole 11H is provided for each liquid jet head 1. A part of the liquid jet head 1 is inserted into each through hole 11H. Note that in Figure 2, some of the liquid jet heads 1 arranged in part of the unit base 11 are not shown in order to show the through holes 11H.

[0019] Furthermore, the unit base 11 is provided with four mounting holes 101 and two third positioning portions 102 for each through hole 11H. The four mounting holes 101 and the two third positioning portions 102 are provided outside the through hole 11H in plan view. Note that the number and arrangement of the mounting holes 101 and the third positioning portions 102 are not limited to the example shown in FIG. 2 and are arbitrary.

[0020] The mounting holes 101 are provided, for example, near the four corners of the through-hole 11H in plan view. The mounting holes 101 are used to mount the liquid jet head 1 to the unit base 11. The mounting holes 101 penetrate the unit base 11, for example, in the thickness direction.

[0021] Each third positioning portion 102 is provided, for example, between two mounting holes 101 aligned in the direction along the X axis and spaced apart from each other. Each third positioning portion 102 is used for positioning when mounting the unit base 11 of the liquid jet head 1. Each third positioning portion 102 is, for example, a bottomed hole that opens on the surface of the unit base 11 facing in the Z1 direction. It can also be said that each third positioning portion 102 is a recess formed in the surface of the unit base 11 facing in the Z1 direction.

[0022] Note that each mounting hole 101 does not have to penetrate the unit base 11 in the thickness direction. Similarly, each third positioning portion 102 may penetrate the unit base 11 in the thickness direction. Furthermore, the shape of the unit base 11 is not limited to a plate shape, and may be, for example, a box shape.

[0023] As described above, the liquid ejection device 100 includes a plurality of liquid ejection heads 1 and a unit base 11 to which the plurality of liquid ejection heads 1 are fixed. The liquid ejection device 100 includes the liquid ejection heads 1 described below. As described below, each of the plurality of liquid ejection heads 1 is detachable from the unit base 11 and is configured to increase the alignment accuracy between the plurality of liquid ejection heads 1. Therefore, according to the liquid ejection device 100, even when any one of the plurality of liquid ejection heads 1 is replaced, it is possible to suppress a decrease in print quality.

[0024] 1-3. Liquid jet head 1 Fig. 3 is a cross-sectional view of the liquid jet head 1 shown in Fig. 2, viewed in the direction along the X axis. Fig. 4 is a cross-sectional view of the liquid jet head 1 shown in Fig. 2, viewed in the direction along the Y axis. As shown in Fig. 4, in this embodiment, the liquid jet head 1 has a configuration that is approximately symmetrical with respect to a central imaginary plane A10 along the XZ plane. However, the liquid jet head 1 does not have to be configured symmetrical with respect to the central imaginary plane A10.

[0025] As shown in either Figure 3 or Figure 4, the liquid jet head 1 includes a plurality of head modules 2, two supply flow path members 3, a sealing member 4, a plurality of covers 5, a holder 6, a plurality of wiring boards 7, and a relay board 70.

[0026] Furthermore, in the liquid jet head 1, the cover 5, the holder 6, and the multiple head modules 2 are detachable from one another. After the cover 5 is removed from the holder 6, each head module 2 can be individually removed from the holder 6. Because each head module 2 can be individually removed from the holder 6, each head module 2 is replaceable.

[0027] 1-3A. Head Module 2 3, the plurality of head modules 2 are six head modules 2. The number of head modules 2 is not limited to six, and may be two or more and five or less, or seven or more.

[0028] In this embodiment, the multiple head modules 2 are aligned along the X axis. As shown in FIG. 4, each head module 2 is elongated along the Y axis. Each head module 2 ejects ink in the Z1 direction. The head module 2 includes a chip 20 and a flow path opening forming member 25. The chip 20 is arranged in the Z1 direction relative to the flow path opening forming member 25.

[0029] FIG. 5 is a bottom view of the liquid jet head 1 shown in FIG. 3. As shown in FIG. 5, each head module 2 has a plurality of nozzles N that eject ink. The plurality of nozzles N are arranged along the Y axis. The plurality of nozzles N are divided into nozzle rows La and nozzle rows Lb that are arranged side by side at intervals along the X axis. Each of the nozzle rows La and Lb is a collection of a plurality of nozzles N that are linearly arranged along the Y axis. Furthermore, the surface of the head module 2 on which the openings of the plurality of nozzles N are formed is referred to as the nozzle surface SN. The nozzle surface SN is the surface of the chip 20 of the head module 2 that faces the Z1 direction. Note that, for example, the plurality of nozzles N may be arranged in a direction that intersects the X axis and the Y axis when viewed in the Z1 direction.

[0030] 1-3Aa. Chip 20 Fig. 6 is a cross-sectional view of the chip 20 included in the head module 2 shown in Fig. 3. The chip 20 has a structure in which elements related to each nozzle N of nozzle row La and elements related to each nozzle N of nozzle row Lb are arranged in a substantially plane-symmetrical manner. In the following explanation, the elements corresponding to nozzle row La will be mainly explained, and explanations of elements corresponding to nozzle row Lb will be omitted as appropriate. Furthermore, in the following, when there is no need to distinguish between nozzle row La and nozzle row Lb, they will be referred to as nozzle row L.

[0031] As shown in FIG. 6, the chip 20 of each head module 2 includes, for example, a communication plate 202, a pressure chamber substrate 203, a vibration plate 204, a nozzle plate 201, a cover 206, a plurality of drive elements E, and a sealing substrate 205.

[0032] The communicating plate 202, pressure chamber substrate 203, diaphragm 204, nozzle plate 201, and cover 206 are each a long plate-like member extending along the Y axis. The pressure chamber substrate 203 is placed on the surface of the communicating plate 202 facing the Z2 direction. The nozzle plate 201 and cover 206 are placed on the surface of the communicating plate 202 facing the Z1 direction. The components are fixed together, for example, with an adhesive.

[0033] The nozzle plate 201 is a plate-like member in which a plurality of nozzles N are formed. The nozzle plate 201 is the member of the head module 2 that is located furthest in the Z1 direction. The surface of the nozzle plate 201 that faces the Z1 direction is the nozzle surface SN. Each of the plurality of nozzles N is a circular through-hole that ejects ink. For example, the nozzle plate 201 is manufactured by processing a silicon (Si) single crystal substrate using semiconductor manufacturing techniques such as photolithography and etching.

[0034] The communicating plate 202 is formed with a plurality of throttle portions R1, a plurality of communicating channels R2, a communicating space Ra, and a common channel Rb. Each of the throttle portions R1 and the communicating channels R2 extends in the Z1 direction and is a through-hole formed for each nozzle N. The communicating channels R2 overlap with the nozzles N in plan view. The communicating spaces Ra are elongated openings formed along the Y axis. The communicating spaces Ra extend along the Y axis. The common channels Rb communicate with the communicating spaces Ra and overlap with the communicating spaces Ra in plan view. The common channels Rb extend along the Y axis. The common channels Rb communicate with the plurality of throttle portions R1. Furthermore, the communicating spaces Ra communicate with the spaces Rc of the channel opening forming member 25.

[0035] The communication space Ra, the common flow path Rb, and the space Rc form a common space R that is shared by multiple nozzles N. The common space R functions as an ink reservoir. The ink stored in the common space R branches off into each throttle section R1 and is supplied to and filled in multiple pressure chambers C in parallel.

[0036] A plurality of pressure chambers C are formed in the pressure chamber substrate 203. The pressure chambers C are located between the communication plate 202 and the vibration plate 204, and are spaces formed by the wall surfaces of the pressure chamber substrate 203. A pressure chamber C is formed for each nozzle N. The pressure chamber C is an elongated space extending in the X1 direction. The plurality of pressure chambers C are arranged along the Y axis.

[0037] The communication plate 202 and the pressure chamber substrate 203 are manufactured by processing a semiconductor substrate such as a silicon single crystal substrate.

[0038] An elastically deformable vibration plate 204 is disposed above the pressure chamber C. The vibration plate 204 is laminated on the pressure chamber substrate 203 and contacts the surface of the pressure chamber substrate 203 opposite the communicating plate 202. The vibration plate 204 is a long, rectangular plate-like member extending along the Y-axis in a plan view. The pressure chamber C communicates with the communicating flow path R2 and the throttle portion R1. Therefore, the pressure chamber C communicates with the nozzle N via the communicating flow path R2, and also communicates with the communicating space Ra via the throttle portion R1. Note that the nozzle N, the communicating flow path R2, the pressure chamber C, and the throttle portion R1 form an individual flow path for each nozzle N. Also, for ease of explanation, the pressure chamber substrate 203 and the vibration plate 204 are illustrated in FIG. 6 as separate substrates, but in reality they are laminated on a single silicon substrate.

[0039] A driving element E is formed for each pressure chamber C on the surface of the vibration plate 204 opposite to the pressure chamber C. The driving element E is an elongated piezoelectric element extending along the X-axis in a plan view. The driving element E includes, for example, a pair of electrodes and a piezoelectric body sandwiched between the pair of electrodes. The driving element E may also be an electrothermal conversion element that generates thermal energy.

[0040] The sealing substrate 205 is a structure that protects the multiple drive elements E. The sealing substrate 205 is fixed to the surface of the diaphragm 204 with, for example, an adhesive. The multiple drive elements E are housed inside a recess formed on the surface of the sealing substrate 205 that faces the diaphragm 204. The sealing substrate 205 also has a through hole 20H for inserting a wiring substrate 7, which will be described later.

[0041] The cover 206 is a thin metal plate that forms the wall surface of the common flow path Rb. The cover 206 has a thickness similar to that of the nozzle plate 201. The planar shape of the cover 206 is, for example, a frame shape that surrounds the nozzle plate 201. A mold 207 made of resin is provided between the cover 206 and the nozzle plate 201. The surface of the cover 206 facing the Z1 direction forms part of the nozzle surface SN.

[0042] In this chip 20, when the drive element E contracts due to energization, the vibration plate 204 bends and deflects in the direction that reduces the volume of the pressure chamber C, causing the pressure inside the pressure chamber C to rise and eject an ink droplet from the nozzle N. At this time, pressure also propagates from the pressure chamber C toward the throttle portion R1, causing ink to flow into the common flow path Rb through the throttle portion R1. After the ink is ejected, the drive element E returns to its original position. At this time, the ink in the common flow path Rb from the nozzle N also vibrates. Then, at the same time as the meniscus of the nozzle N returns to its original position, ink is supplied from the throttle portion R1. Through this series of operations, ink is ejected from the nozzle N.

[0043] The chip 20 of this embodiment includes all of the elements shown in FIG. 3, but the components of the chip 20 do not necessarily have to include all of the elements, and may further include additional elements.

[0044] The chip 20 may have, for example, a monolithic structure and be thinner than the flow path opening-forming member 25, e.g., a component having a thickness of less than 3000 μm. The chip 20 may be a component having a thickness of 1500 μm or less, or 1000 μm or less. The thickness of the chip 20 may be ⅕ or less of the length of the short side as viewed in the direction along the Z axis, which is the thickness direction of the chip 20. The chip 20 may include at least one element of the nozzle plate 201, the pressure chamber substrate 203, the communication plate 202, or the driving element E, and the sealing substrate 205. The chip 20 preferably includes at least the nozzle plate 201, more preferably further includes the pressure chamber substrate 203, and particularly preferably further includes the communication plate 202. At least one of the nozzle plate 201, the pressure chamber substrate 203, the communication plate 202, the pressure chamber substrate 203 on which the driving element E is stacked, and the sealing substrate 205 may be considered to be the chip 20. Furthermore, the chip 20 may be not only a laminate of silicon substrates manufactured by MEMS, but also a laminate of thin plates such as ceramic sheets or metals, or a laminate of thin plate-like members of each of the aforementioned materials.

[0045] 1-3Ab. Flow path opening forming member 25 4 and 6, a flow path opening forming member 25 is disposed in the Z2 direction of the chip 20. The flow path opening forming member 25 and the chip 20 are fixed to each other, for example, by an adhesive or the like. The flow path opening forming member 25 and the chip 20 are positioned with high precision in advance. The flow path opening forming member 25 also has a flow path that supplies ink to the chip 20, for example.

[0046] Furthermore, the flow path opening forming member 25 is preferably a member having a thickness of, for example, 3000 μm or more, more preferably a member having a thickness of 5000 μm or more, and even more preferably a member having a thickness of 8000 μm or more. The flow path opening forming member 25 may be formed of a single member or may be a laminate of multiple members. The flow path opening forming member 25 is made of metal, but may also be made of thermosetting resin. By forming the flow path opening forming member 25 from thermosetting resin, costs can be reduced. When the flow path opening forming member 25 is made of metal, the same metal material as that of the holder 6 described below may be used. However, by forming the flow path opening forming member 25 from metal, it is easier to reuse the flow path opening forming member 25 when the head module 2 is replaced. Furthermore, compared to when it is made of resin, using metal allows for more accurate positioning of the flow path opening forming member 25 relative to the holder 6.

[0047] 4, the length of the flow path opening-forming member 25 in the direction along the Z axis, i.e., the thickness, is thicker than the thickness D2 of the chip 20. The thickness of the flow path opening-forming member 25 here is the thickness at a position overlapping with a sealing region 4S, which will be described later, when viewed in the Z1 direction. In other words, the chip 20 is thinner than the flow path opening-forming member 25. The flow path opening-forming member 25 also includes a surface 251 facing the Z1 direction and a surface 252 facing the Z2 direction.

[0048] Fig. 7 is a top view of the flow path opening forming member 25 included in the head module 2 shown in Fig. 4. As shown in Fig. 7, the planar shape of the flow path opening forming member 25 is larger than the planar shape of the chip 20. That is, the chip 20 has a smaller outer shape than the flow path opening forming member 25 when viewed in the Z1 direction. The flow path opening forming member 25 is disposed so as to overlap and cover the chip 20 when viewed in the Z1 direction.

[0049] As shown in FIGS. 4 and 7, the flow path opening forming member 25 has a flange portion 250 for fixing to the cover 5 described later. The planar shape of the flange portion 250 is a rectangular frame shape surrounding an opening 5H of the cover 5 described later. As shown in FIG. 5, the surface of the flange portion 250 facing the Z1 direction is a supported surface 2511 that is supported by the cover 5 described later. Because the planar shape of the flange portion 250 is a rectangular frame shape surrounding the opening 5H, the planar shape of the supported surface 2511 is also a rectangular frame shape surrounding the opening 5H. The supported surface 2511 is located further in the Z2 direction than the chip 20. Therefore, the supported surface 2511 is located in the Z2 direction of the nozzle plate 201.

[0050] 7, a through hole 25H is provided in the flow path opening forming member 25. A wiring substrate 7, which will be described later, is inserted into the through hole 25H. The through hole 25H is provided in the center of the flow path opening forming member 25 in plan view. Referring to FIG. 6, the through hole 25H overlaps with the through hole 20H of the sealing substrate 205 in plan view.

[0051] 4 and 6, a flow path 25R is formed inside the flow path opening forming member 25. The flow path 25R is provided to supply ink to the chip 20. As shown in Fig. 6, a space Rc is provided on the chip 20 side of the flow path 25R, i.e., on the downstream side. The flow path 25R and the space Rc are in communication with each other.

[0052] As shown in FIG. 4, a plurality of flow path openings 251H are provided on the side of the flow path 25R of the flow path opening forming member 25 opposite to the chip 20, i.e., on the upstream side. Each flow path opening 251H is an open end of the flow path 25R in the Z2 direction. The flow path opening 251H is an opening for connecting the flow path 25R of the flow path opening forming member 25 of the head module 2 with a flow path 6R of the holder 6, which will be described later. As shown in FIGS. 4 and 7, the plurality of flow path openings 251H are provided in the flange portion 250 of the flow path opening forming member 25. The flow path openings 251H are arranged outside the chip 20 when viewed in the Z1 direction. In this embodiment, two flow path openings 251H are provided for each nozzle row L.

[0053] 4 and 7, each flow path opening forming member 25 is provided with two fixing holes 215 and two first positioning portions 216. The head module 2 including the flow path opening forming member 25 is detachable from the holder 6. Each first positioning portion 216 is used for positioning the head module 2 relative to the holder 6. Each fixing hole 215 is used for fixing the head module 2 to the holder 6.

[0054] Each first positioning portion 216 is provided on a surface 252 of the flow path opening forming member 25 facing the Z2 direction. This surface 252 is also the surface of the head module 2 facing the Z2 direction. In this embodiment, each first positioning portion 216 is a protrusion that protrudes in the Z2 direction from the surface 252 of the flow path opening forming member 25 facing the Z2 direction. The two first positioning portions 216 are provided on both sides of the opening 5H of the holder 6 in the longitudinal direction of the flow path opening forming member 25. One of the two first positioning portions 216 is located in the Y1 direction with respect to the opening 5H, and the other is located in the Y2 direction with respect to the opening 5H.

[0055] Each fixing hole 215 is provided in a surface 252 facing the Z2 direction of the flow path opening-forming member 25. Each fixing hole 215 is a bottomed hole that opens in the surface 252 facing the Z2 direction of the flow path opening-forming member 25. Each fixing hole 215 is a recessed portion provided in the surface 252 facing the Z2 direction of the flow path opening-forming member 25, and can also be considered to be a depression formed in the surface 252. Two fixing holes 215 are provided in the longitudinal direction of the flow path opening-forming member 25, on both sides of the through-hole 25H and on both sides of the opening 5H of the holder 6. One of the two fixing holes 215 is located in the Y1 direction with respect to the opening 5H, and the other is located in the Y2 direction with respect to the opening 5H.

[0056] Each fixing hole 215 positioned in the Y1 direction relative to the opening 5H is closer to the opening 5H than the first positioning portion 216 positioned in the Y1 direction relative to the opening 5H. Similarly, each fixing hole 215 positioned in the Y2 direction relative to the opening 5H is closer to the opening 5H than the first positioning portion 216 positioned in the Y2 direction relative to the opening 5H. The first positioning portions 216 and the fixing holes 215 do not overlap with the opening 5H when viewed in the Z1 direction. Furthermore, the two flow path openings 251H, the fixing holes 215, and the first positioning portion 216 are located farthest from the opening 5H in this order. Of these, the two flow path openings 251H are closest to the opening 5H.

[0057] The shortest distance between the fixing hole 215 and the opening 5H is shorter than the shortest distance between the first positioning portion 216 and the opening 5H, but it may be longer. Furthermore, the first positioning portion 216, the fixing hole 215, and the opening 5H are aligned along the longitudinal direction of the cover 5, but they do not have to be aligned. For example, the first positioning portion 216 may be provided on both sides of the opening 5H in the X-axis direction.

[0058] 1-3B. Holder 6 3 and 4, the holder 6 holds and houses the plurality of head modules 2, and has a common flow path that supplies and distributes ink to the plurality of head modules 2. The holder 6 is common to the plurality of head modules 2.

[0059] As shown in FIG. 4 , the holder 6 of this embodiment has a member in which both one flow path 6R and multiple second positioning portions 653 are formed. The flow path 6R supplies ink to each head module 2 and distributes the ink to each head module 2. The holder 6 is equipped with a supply flow path member having a flow path 6R, which is a common flow path. The flow path 6R is a common flow path shared by multiple head modules 2, and has a common portion 6RA extending along the X-axis and multiple branch portions 6RB branching from the common portion 6RA and extending in the Z1 direction. Although not shown, the holder 6 is provided with a flow path joint for connecting to a supply flow path outside the liquid jet head 1 to communicate with the liquid storage portion 9. This flow path joint, not shown, is exposed to the outside of the liquid jet head 1, for example, through an opening, not shown, formed in the holder 6.

[0060] The holder 6 may have a plurality of flow paths 6R that communicate with a plurality of head modules 2. In other words, the flow path 6R may not have a common portion 6RA that communicates with a plurality of head modules 2, but may have a plurality of flow paths 6R that communicate with each of the plurality of head modules 2.

[0061] A flow path opening 650H is provided on the head module 2 side of the flow path 6R, i.e., on the downstream side. The flow path opening 650H is an open end of the flow path 6R in the Z1 direction. The flow path opening 650H is provided corresponding to the flow path opening 251H of the head module 2. The flow path opening 650H is an opening for connecting the flow path 25R of the head module 2 and the flow path 6R of the holder 6.

[0062] 8 is a bottom view showing the holder 6 and relay board 70 shown in FIG. 4. As shown in FIGS. 3, 4, and 8, the holder 6 is box-shaped and has a recess 610 that opens in the Z1 direction. Multiple head modules 2 are arranged in the storage space inside the recess 610 of the holder 6. It can also be said that the storage space for the multiple head modules 2 is formed by the holder 6 and a cover 5, which will be described later. The holder 6 is made of a metal such as aluminum, titanium, stainless steel, 42 Alloy, or Invar.

[0063] As shown in FIGS. 4 and 8, the recess 610 includes a first recess 611 and a second recess 612. As shown in FIG. 4, the second recess 612 is formed on the bottom surface of the first recess 611. The first recess 611 is located in the Z1 direction from the center of the holder 6 in the Z axis. The second recess 612 is located in the Z2 direction from the center of the holder 6 in the Z axis. The opening area of ​​the second recess 612 is larger than the opening area of ​​the first recess 611. Therefore, the recess 610 has a stepped surface.

[0064] The relay substrate 70 is bonded to the bottom surface of the recess 610, specifically the bottom surface of the second recess 612, for example, by an adhesive. Although not shown in detail, the holder 6 has an opening through which an external wiring member of the liquid jet head 1 is inserted to electrically connect the relay substrate 70 and the control unit 91.

[0065] 3, the holder 6 includes a flat plate portion 61, a side wall portion 62, and two flange portions 64. The flat plate portion 61, the side wall portion 62, and the two flange portions 64 are integrally formed.

[0066] FIG. 9 is a top view of the holder 6 shown in FIG. 3. FIG. 10 is a plan view of the lower part of the holder 6 shown in FIG. 3. As shown in FIG. 3, 4 or 9, the flat plate portion 61 is a flat plate-shaped portion along the XY plane and is located in the Z2 direction of the supply flow path member 3. The side wall portion 62 is a portion extending in the Z1 direction from the outer edge of the flat plate portion 61. The planar shape of the side wall portion 62 is a quadrangular frame shape. The aforementioned stepped surface is provided on the inner wall surface of the side wall portion 62.

[0067] The first recess 611 is provided in the lower part of the holder 6, and the second recess 612 is provided in the upper part of the holder 6.

[0068] 4, the holder 6 has a plurality of fixing holes 651H, a plurality of fixing holes 652H, and a plurality of second positioning portions 653. Each fixing hole 651H is used to fix the holder 6 and the head module 2. Each fixing hole 652H is used to fix the holder 6 and the cover 5. Each second positioning portion 653 is used to position the head module 2 relative to the holder 6.

[0069] Each fixing hole 651H is a hole that penetrates the holder 6 in the Z1 direction. Two fixing holes 651H are provided for each head module 2. Each fixing hole 651H is provided in the Y1 direction or the Y2 direction relative to the second recess 612 when viewed in the Z1 direction. The two fixing holes 651H are provided corresponding to the two fixing holes 215 described above and overlap with the two fixing holes 215 when viewed in the Z1 direction. Each fixing hole 651H does not overlap with the chip 20 when viewed in the Z1 direction, but overlaps with the flow path opening forming member 25. The opening end of each fixing hole 651H in the Z1 direction opens to the bottom surface of the first recess 611 when viewed in the Z1 direction.

[0070] Each fixing hole 652H is a hole that penetrates the holder 6 in the Z1 direction. As shown in Fig. 10, the multiple fixing holes 652H are, for example, four fixing holes 652H, and each fixing hole 652H is provided at one of the four corners of the rectangular holder 6 when viewed in the Z1 direction. As shown in Fig. 4, each fixing hole 652H is provided to correspond to the fixing hole 503 of the cover 5. Each fixing hole 652H overlaps with the fixing hole 503 when viewed in the Z1 direction. Each fixing hole 652H does not overlap with the recess 610 when viewed in the Z1 direction.

[0071] Each second positioning portion 653 is provided on the surface 605 of the holder 6 facing the Z1 direction. Two second positioning portions 653 are provided for each head module 2. In this embodiment, each second positioning portion 653 is a bottomed hole that opens on the surface 605 of the holder 6 facing the Z1 direction, specifically, on the bottom surface of the first recess 611. Each second positioning portion 653 is also a recess formed on the surface 605 of the holder 6 facing the Z1 direction, specifically, on the bottom surface of the first recess 611. Each second positioning portion 653 is provided in the Y1 direction or Y2 direction of the second recess 612 as viewed in the Z1 direction. Furthermore, the two second positioning portions 653 are provided corresponding to the two first positioning portions 216 described above and overlap the two first positioning portions 216 as viewed in the Z1 direction. Therefore, the multiple second positioning portions 653 are provided in one-to-one correspondence with the multiple first positioning portions 216.

[0072] Each second positioning portion 653 is press-fitted into the above-mentioned first positioning portion 216 to position the cover 5 relative to the holder 6. Furthermore, the first positioning portion 216 and the second positioning portion 653 are provided for each head module 2.

[0073] Of fixing hole 651H, second positioning portion 653, and fixing hole 652H, fixing hole 651H is closest to opening 5H and fixing hole 652H is farthest from opening 5H when viewed in the Z1 direction. Note that the distances between fixing hole 651H, second positioning portion 653, and fixing hole 652H and opening 5H may be the same or different.

[0074] Each first positioning portion 216 of the flow path opening forming member 25 is press-fitted into the second positioning portion 653, thereby positioning the head module 2 with respect to the holder 6. Furthermore, the first positioning portion 216 and the second positioning portion 653 are provided for each head module 2.

[0075] The provision of the first positioning portion 216 and the second positioning portion 653 described above makes it easy to position the head module 2 when attaching it to the holder 6. Furthermore, the provision of the first positioning portion 216 and the second positioning portion 653 for each head module 2 makes it possible to align the multiple head modules 2 with high precision. Therefore, when replacing only some of the multiple head modules 2, it is not necessary to redo the alignment of all of the head modules 2.

[0076] Furthermore, alignment between the multiple head modules 2 can be performed with high precision by the simple method of press-fitting the first positioning portion 216 into the second positioning portion 653. This makes it easy to replace a desired head module 2 from among the multiple head modules 2. Therefore, it is easy to recycle the liquid jet head 1 by replacing the head module 2.

[0077] Note that press-fitting refers to interference fitting or intermediate fitting. A state in which the first positioning portion 216 is in contact with the second positioning portion 653 at at least two points when the first positioning portion 216 is completely inserted into the second positioning portion 653 is called a press-fit state. Also, before press-fitting, the length of the longest line segment connecting two points on the outer periphery of the first positioning portion 216, which is a positioning pin, when viewed in the direction along the Z axis is greater than the diameter of the largest circle inscribed in the second positioning portion 653, which is a positioning hole. Also, in the press-fit state, the force of press-fitting fits the head module 2 into the holder 6 to such an extent that it does not fall under its own weight.

[0078] As described above, the flow path opening 650H and the flow path opening 251H correspond to each other. Specifically, the flow path opening 650H and the flow path opening 251H overlap when viewed in the direction in which one of the first positioning portion 216 and the second positioning portion 653 is press-fitted into the other, i.e., the direction along the Z axis. That is, the direction in which the flow path opening 650H and the flow path opening 251H overlap is the same as the direction in which the second positioning portion 653 is press-fitted into the first positioning portion 216. Therefore, when the head module 2 is attached to the holder 6, the flow path connection between the flow path 6R and the flow path 25R can be performed easily and with high accuracy.

[0079] The multiple second positioning portions 653 are arranged on a surface 605 of the holder 6 facing the Z1 direction, specifically, on the bottom surface of the first recess 611. The first positioning portion 216 is arranged on a surface 252 of the flow path opening forming member 25 facing the Z2 direction, which is the opposite direction to the Z1 direction.

[0080] By arranging the first positioning portion 216 and the second positioning portion 653 in this manner, it is possible to easily attach and detach only the head module 2 to be replaced from below the holder 6. Therefore, when replacing the head module 2 to be replaced with a subunit 15 including a head module 2 that is not faulty and reattaching it to the holder 6, it is only necessary to connect the flow paths of the head module 2 to be replaced to the holder 6. Therefore, it is not necessary to connect the flow paths of head modules 2 other than the head module 2 to be replaced to the holder 6. This makes it possible to simplify the attachment and detachment work when repairing the liquid jet head 1.

[0081] Furthermore, as described above, the holder 6 can be considered to be equipped with a common flow path member having one or more flow paths 6R that communicate with the multiple head modules 2. The holder 6, which includes the common flow path member, is disposed in the Z2 direction relative to the multiple head modules 2, and overlaps the multiple head modules 2 when viewed in the Z1 direction. Furthermore, the first positioning portion 216 is provided on a surface 252 of the flow path opening forming member 25 that faces the Z2 direction. This makes it easy to attach and detach only the head module 2 to be replaced from below. This eliminates the need to disconnect the flow paths between the holder 6 and head modules 2 other than the one to be replaced, simplifying the attachment and detachment work.

[0082] As described above, the first positioning portion 216 is provided on the surface of the flow path opening forming member 25 opposite to the surface on which the chip 20 is provided, i.e., the surface 252 in the Z2 direction. The first positioning portion 216 does not overlap with the chip 20 when viewed in the Z1 direction. By arranging the first positioning portion 216 in this manner, when the second positioning portion 653 of the holder 6 is press-fitted into the first positioning portion 216, it is possible to prevent the load caused by the press-fitting from acting on the chip 20.

[0083] As described above, the holder 6 also has a plurality of fourth positioning portions 642. The plurality of fourth positioning portions 642 are provided on the flange portion 64. As shown in FIG. 4, the fourth positioning portions 642 are protrusions that protrude in the Z2 direction from a surface of the flange portion 64 facing the Z2 direction. The plurality of fourth positioning portions 642 are provided in one-to-one correspondence with the plurality of third positioning portions 102 of the unit base 11 shown in FIG. 2.

[0084] The fourth positioning portion 642 is press-fitted into one of the plurality of third positioning portions 102 provided on the unit base 11, thereby positioning the liquid jet head 1 with respect to the unit base 11. This makes it possible to improve the alignment accuracy between the plurality of liquid jet heads 1 with respect to the unit base 11.

[0085] 9, the flange portion 64 is provided with mounting holes 64H. The mounting holes 64H correspond to the mounting holes 101 of the unit base 11. Each mounting hole 64H is, for example, a bottomed hole that opens on the surface of the flange portion 64 in the Z2 direction, and is, for example, a screw hole for mounting the liquid jet head 1 to the unit base 11 with a member such as a screw. The flange portion 64 and the unit base 11 are fixed together by inserting screws or the like (not shown) through the mounting holes 64H and then the mounting holes 101 and fastening them together with the screws. As a result, the liquid jet head 1 is fixed to the unit base 11.

[0086] 1-3C. Sealing member 4 As shown in FIGS. 3 and 4 , the sealing member 4 is provided between each head module 2 and the holder 6 in the Z1 direction. A sealing member 4 is provided for each head module 2. The sealing member 4 has elasticity. The sealing member 4 is made of an elastic material such as an elastomer. In this embodiment, the length of the sealing member 4 along the Z axis, i.e., the thickness, is constant. The thickness of the sealing member 4 is thinner than the thicknesses of the flow path opening forming member 25 and the holder 6. The sealing member 4 is crushed by the head module 2 and the holder 6.

[0087] 11 is a top view of the sealing member 4 shown in FIG. 4. In the example shown in FIG. 11, two sealing members 4 are provided for each head module 2. The two sealing members 4 are provided at both longitudinal ends of one head module 2. Each sealing member 4 is rectangular when viewed in the Z1 direction. When viewed in the Z1 direction, each sealing member 4 overlaps with a flange portion 250 of the flow path opening forming member 25 of the head module 2. On the other hand, in this embodiment, the sealing member 4 is provided at a position different from the chip 20 when viewed in the Z1 direction. In other words, the sealing member 4 does not overlap with the chip 20 when viewed in the Z1 direction.

[0088] As shown in FIGS. 4 and 11 , each sealing member 4 has two communication ports 4H. As shown in FIG. 4 , each communication port 4H is provided corresponding to one flow path opening 251H of the flow path opening forming member 25 and one flow path opening 650H of the holder 6. As shown in FIG. 11 , the communication ports 4H overlap with the flow path opening 650H and the flow path opening 251H, respectively, when viewed in the Z1 direction. As shown in FIG. 4 , the communication port 4H is connected to the flow path 25R via the flow path opening 251H. The communication port 4H is connected to the flow path 6R via the flow path opening 650H. Therefore, the flow path 25R and the flow path 6R are in communication with each other via the communication port 4H. Specifically, the sealing member 4 is compressed between the flow path opening forming member 25 and the holder 6, thereby connecting the flow path 25R and the flow path 6R with each other via the communication port 4H.

[0089] The sealing member 4 is a member that liquid-tightly connects the flow path opening 251H of the head module 2 and the flow path opening 650H of the holder 6. The ink flowing through the flow path 6R of the holder 6 flows into the flow path 25R of the flow path opening forming member 25 through the communication port 4H, and is supplied to the individual flow paths of the chip 20 through the common space R.

[0090] As shown in FIG. 11 , the seal member 4 has a seal region 4S. In this embodiment, the entire seal member 4 corresponds to the seal region 4S. The seal region 4S is in contact with both the flow path opening-forming member 25 and the holder 6, and is a region of the seal member 4 that is sandwiched between the flow path opening-forming member 25 and the holder 6. The seal region 4S is a region that is crushed by the load from the flow path opening-forming member 25 and the holder 6 to liquid-tightly connect the flow path opening 251H and the flow path opening 650H to each other. In other words, even if a region of the seal member 4 is sandwiched between both the flow path opening-forming member 25 and the holder 6, a portion that is not crushed by the load from both members and does not substantially contribute to liquid-tightly connecting the flow path opening 251H and the flow path opening 610H to each other is not included in the seal region 4S.

[0091] 11, the sealing member 4 is provided at a position different from the chip 20 when viewed in the Z1 direction, and therefore the sealing area 4S is provided at a position different from the chip 20 when viewed in the Z1 direction. In other words, the sealing area 4S does not overlap with the chip 20 when viewed in the Z1 direction. Because the sealing area 4S does not overlap with the chip 20 when viewed in the Z1 direction, the reaction force of the sealing member 4 is less likely to affect the chip 20 compared to when they overlap. This makes it possible to improve the reliability of the head module 2.

[0092] As described above, the sealing member 4 is crushed between the flow path opening forming member 25 and the holder 6, so that the flow path 25R and the flow path 6R communicate with each other via the communication port 4H. The reaction force of the crushed sealing member 4 applies stress to the chip 20, which may cause warping of the chip 20. If the reaction force of the sealing member 4 acts on the chip 20 in this way, for example, the nozzle plate 201 may be deformed, causing the nozzles N to shift in position, the pressure chamber substrate 203 or the communication plate 202 may be deformed, causing changes in ejection characteristics, or if the components constituting the chip 20 include a silicon substrate or a ceramic sheet, the component may be cracked, which may result in a decrease in reliability of the head module 2.

[0093] In this embodiment, the sealing area 4S of the sealing member 4 does not overlap with the chip 20 when viewed in the Z1 direction. This makes it possible to suppress a decrease in the sealing performance of the sealing member 4, while also suppressing the effect of the reaction force of the sealing member 4 on the chip 20. This makes it possible to improve the reliability of the head module 2.

[0094] Furthermore, the sealing members 4 corresponding to each of the plurality of head modules 2 included in the liquid jet head 1 do not overlap with the chip 20 when viewed in the Z1 direction. Therefore, in the plurality of head modules 2, it is possible to suppress a decrease in the sealing performance due to the sealing members 4, while also suppressing the effect of the reaction force of the sealing members 4 on the chip 20. This makes it possible to improve the reliability of the liquid jet head 1.

[0095] 11, the communication port 4H, the flow path opening 251H, and the flow path opening 650H do not overlap with the chip 20 when viewed in the Z1 direction. The communication port 4H, the flow path opening 251H, and the flow path opening 650H are each disposed outside the chip 20 when viewed in the Z1 direction. Specifically, the communication port 4H, the flow path openings 251H, and 660H are disposed on both longitudinal sides of the chip 20 when viewed in the Z1 direction. Therefore, as described above, the sealing region 4S of the sealing member 4 that liquid-tightly seals the flow paths 25R and 6R can be disposed outside the chip 20. Therefore, as described above, the influence of the reaction force of the sealing member 4 on the chip 20 can be suppressed.

[0096] Furthermore, the sealing area 4S is arranged in the Y1 or Y2 direction, which is the longitudinal direction of the head module 2 relative to the chip 20, when viewed in the Z1 direction. By arranging the sealing area 4S in the longitudinal direction of the chip 20, it is possible to prevent the sealing area 4S from being arranged between adjacent chips 20. Therefore, providing the sealing area 4S prevents the distance between adjacent chips 20 from becoming too large. This makes it less likely that the printing quality will be affected.

[0097] The sealing region 4S may be provided in the direction in which the plurality of head modules 2 are lined up relative to the chip 20, i.e., in the short-side direction of the head modules 2. The sealing member 4 may be provided in the direction in which the plurality of head modules 2 are lined up relative to the chip 20, i.e., in the short-side direction of the head modules 2.

[0098] 1-3D.Cover 5 The cover 5 shown in FIGS. 3 and 4 is a support member that supports the multiple head modules 2. The cover 5 is common to the multiple head modules 2, but may be provided individually for each head module 2. The cover 5 is a long, flat member that is aligned along the Y axis and whose thickness direction is along the Z axis. The cover 5 is disposed in the Z1 direction relative to the multiple flow path opening forming members 25. The cover 5 is a member that sandwiches the seal member 4 and the flow path opening forming members 25 between itself and the holder 6. As shown in FIG. 4, the cover 5 includes a surface 511 facing the Z1 direction and a surface 512 facing the Z2 direction. The cover 5 is a member that does not have a flow path through which ink flows.

[0099] Each cover 5 is detachably fixed to a holder 6, which will be described later. Specifically, the cover 5 is not joined with an adhesive or the like. Furthermore, the cover 5 is detachable from the holder 6. Therefore, each cover 5 can be removed from the holder 6. The cover 5 can also be considered as a sub-holder of the holder 6.

[0100] Furthermore, in this embodiment, one cover 5 detachably holds one head module 2. Therefore, each head module 2 is detachable from the cover 5. Therefore, for example, when one of the multiple head modules 2 included in the head unit 10 is broken, the liquid jet head 1 can be refurbished by replacing the subunit 15 including the broken head module 2 with another subunit 15 including a head module 2 that is not broken.

[0101] It is preferable that the cover 5 and the plurality of head modules 2 are fixed with an adhesive, but each head module 2 may be configured to be removable from the cover 5 by disassembling the adhesive.

[0102] The cover 5 is made of, for example, a metal. The cover 5 is made of, for example, a metal such as aluminum or stainless steel. The cover 5 has enough rigidity to support the plurality of head modules 2.

[0103] As shown in FIGS. 4 and 5, the cover 5 is provided with a plurality of openings 5H. Each opening 5H is a hole that penetrates the cover 5 in the thickness direction. Each opening 5H is provided to expose a part of the head module 2 to the outside. Specifically, the chip 20 is exposed from the opening 5H. Therefore, a plurality of nozzles N are exposed from the opening 5H.

[0104] FIG. 12 is a top view of the cover 5 shown in FIG. 4. As shown in FIGS. 4 and 12, the cover 5 includes a plurality of support regions 5S. The support regions 5S are part of the surface 512 of the cover 5 facing the Z2 direction. In FIG. 12, the support regions 5S are shaded to facilitate understanding. In the example of FIG. 12, the support regions S5 are rectangular frame-shaped when viewed in the Z1 direction.

[0105] 4, the support region 5S is in contact with the flow path opening-forming member 25 and is a region that directly supports the flow path opening-forming member 25. The support region 5S is in contact with the supported surface 2511 of the flow path opening-forming member 25. The support region 5S also includes a region S50 that overlaps with the sealing region 4S when viewed in the Z1 direction. In FIG. 12, the region S50 is indicated by dots.

[0106] Since the support region 5S includes a region S50 that overlaps with the sealing region 4S when viewed in the Z1 direction, the cover 5 receives the reaction force of the sealing member 4 perpendicularly. Therefore, the cover 5 can firmly support the sealing region 4S of the sealing member 4 between itself and the holder 6. This makes it possible to particularly effectively mitigate the reaction force of the sealing member 4.

[0107] Furthermore, a portion of the surface 251 of the flow path opening forming member 25 facing the Z1 direction has a supported surface 2511. When viewed in the Z1 direction, the supported surface 2511 is supported so as to surround the opening 5H of the cover 5 and come into contact with the cover 5. Specifically, the head module 2 is held by the cover 5 as a result of the supported surface 2511 coming into contact with the support region S5 of the cover 5. By supporting the flow path opening forming member 25 by the cover 5 in this manner, the load of the seal member 4 can be dispersed. This makes it possible to make the flow path opening forming member 25 less likely to break.

[0108] The contact between the supported surface 2511 and the support region 5S includes both direct contact and connection via an adhesive, an elastic bush, or the like. Therefore, the flow path opening-forming member 25 may be in direct contact with the cover 5, or indirect contact via an adhesive or another member such as a bush. The flange portion 250 does not have to be a rectangular frame in plan view. For example, the flange portion 250 may be rectangular and provided in both the Y1 direction and the Y2 direction relative to the opening 5H in plan view.

[0109] Furthermore, the thickness of the flange portion 250, i.e., the length along the Z1 direction, is preferably thicker than the thickness of the portion disposed within the opening 5H of the flow path opening-forming member 25. Furthermore, the thickness of the flange portion 250 is preferably at least half the maximum thickness of the flow path opening-forming member 25. Such a thickness relationship prevents a decrease in the strength of the flange portion 250, and makes it easy to ensure strength when subjected to the reaction force of the sealing member 4.

[0110] Furthermore, thickness D5 of cover 5 in the Z1 direction is greater than thickness D2 of chip 20 in the Z1 direction. Thickness D5 is greater than thickness D2. This reduces the risk of cover 5 being deformed by the reaction force of seal member 4.

[0111] Furthermore, thickness D5 of cover 5 is preferably at least twice, and more preferably at least three times, thickness D2 of chip 20. This further reduces the risk of cover 5 being deformed by the reaction force of seal member 4. Note that thickness D5 may be equal to or less than thickness D2.

[0112] From the same viewpoint, the thickness D5 of the cover 5 is preferably 1 mm or more, and more preferably 2 mm or more. Furthermore, the thickness D5 may be 3 mm or more, 5 mm or more, or 6 mm or more to further increase the strength of the cover 5. From the viewpoint of increasing the distance between the medium 90 and the nozzle surface SN, i.e., the paper gap, the thickness D5 of the cover 5 is preferably 10 mm or less, and more preferably 7 mm or less.

[0113] 4, in addition to the chip 20, a portion of the flow path opening forming member 25 is disposed within the opening 5H of the cover 5. That is, a portion of the flow path opening forming member 25 is inserted into the opening 5H of the cover 5. When the cover 5 is present, the paper gap may increase depending on the thickness D5 of the cover 5. Specifically, if the thickness D5 of the cover 5 is excessively large, the surface of the chip 20 facing the Z1 direction may be positioned further in the Z2 direction than the surface of the cover 5 facing the Z1 direction. This increase in distance may result in a decrease in the accuracy of the ink landing position on the medium 90.

[0114] In this embodiment, as described above, in addition to the chip 20, a portion of the flow path opening forming member 25 is disposed within the opening 5H. Therefore, even if the thickness D5 of the cover 5 is increased to further increase the strength of the cover 5, an increase in the paper gap can be prevented.

[0115] Furthermore, the surface of the nozzle plate 201 of the chip 20 facing the Z1 direction, i.e., the nozzle surface SN, and the surface 511 of the cover 5 facing the Z1 direction are substantially flush with each other. That is, the nozzle surface SN and the surface 511 of the cover 5 facing the Z1 direction are at the same position on the Z axis. Therefore, an increase in the paper gap can be suppressed compared to when the nozzle surface SN is positioned further in the Z2 direction than the surface of the cover 5 facing the Z1 direction. Furthermore, it is easy to wipe the surface 511 of the cover 5 facing the Z1 direction and the nozzle surface SN together.

[0116] The nozzle surface SN and the surface 511 of the cover 5 facing the Z1 direction being approximately flush with each other means that they are not only completely flush with each other, but also include cases where there is a step to the extent that it includes manufacturing errors, etc.

[0117] The nozzle surface SN and the surface 511 of the cover 5 facing the Z1 direction do not have to be substantially flush. The nozzle surface SN and the surface 511 of the cover 5 facing the Z1 direction may be at different positions on the Z axis, and a step may exist between these surfaces. In this case, from the perspective of ease of wiping, the distance between the nozzle surface SN and the surface 511 of the cover 5 facing the Z1 direction is preferably 100 μm or less, and more preferably 50 μm or less.

[0118] As shown in FIG. 4, the cover 5 has a plurality of fixing holes 503. Each fixing hole 503 is used to fix the cover 5 to the holder 6. As shown in FIG. 4, each fixing hole 503 is provided on a surface 512 of the cover 5 facing the Z2 direction. Each fixing hole 503 is a bottomed hole provided on the surface 512 of the cover 5 facing the Z2 direction. Each fixing hole 503 is also a recess provided on the surface 512 of the cover 5 facing the Z2 direction, and can be considered to be a depression formed on the surface 512. The multiple fixing holes 503 correspond one-to-one to the multiple fixing holes 652H described above and overlap when viewed in the Z1 direction.

[0119] The cover 5 is fixed so as to come into contact with the outer peripheral wall of the recess 610, i.e., the surface 605 of the holder 6 facing the Z1 direction. Specifically, the holder 6 and the cover 5 are fixed together by inserting fixing members 157 (described later) into the fixing holes 652H and the fixing holes 503. As described above, the cover 5 has a plurality of openings 5H for exposing each of the plurality of head modules 2 to the outside.

[0120] By providing such a cover 5, it is possible to prevent ink mist from entering the recess 610 of the holder 6 while the cover 5 exposes the nozzle surface SN, which is the ink ejection surface.

[0121] Furthermore, one cover 5 is provided for each holder 6, but multiple covers 5 may be provided. For example, a cover 5 that holds three of the six head modules 2 and a cover 5 that holds the remaining three head modules 2 may be provided.

[0122] For example, two or more head modules 2 that are to be replaced at similar times are held by one cover 5. This makes it possible to replace two or more head modules 2 that are to be replaced at similar times together, making the work easier.

[0123] Specifically, for example, it is preferable that the cover 5 holds, among the plurality of head modules 2, a plurality of head modules 2 that eject the same type of liquid. This allows chips that are nearing the end of their lifespan, for example, colors with a high ejection frequency, to be replaced all at once. This improves the workability of replacement. Note that the two or more head modules 2 held by one cover 5 do not have to eject the same type of ink. Furthermore, one head module 2 may be capable of ejecting one type of ink, or may be capable of ejecting two or more types of ink.

[0124] 1-3E. Fixing member group 150 As shown in FIG. 4, the fixing member group 150 includes a plurality of fixing members 155 and a plurality of fixing members 157.

[0125] The fixing member 155 fixes the holder 6 and the cover 5. The fixing member 155 is inserted through the fixing hole 652H, which is a through-hole, and then through the recessed fixing hole 503. Therefore, the fixing member 155 is not exposed on the nozzle surface SN side. On the other hand, a portion of the fixing member 155 is exposed on the surface 606 of the holder 6 facing the Z2 direction.

[0126] For example, after removing the fixing member 155 from the fixing hole 652H, a long rod-shaped member is inserted into the fixing hole 652H and the member is used to press the cover 5 in the Z1 direction. This makes it possible to easily release the cover 5 from being pressed into the holder 6. In other words, by using the fixing hole 652H as a hole for releasing the press-fit, the cover 5 from being pressed into the holder 6 can be easily released.

[0127] The fixing member 157 directly fixes the holder 6 and the head module 2. The fixing member 157 is inserted through the fixing hole 651H, which is a through-hole, and the recessed fixing hole 215, in that order. Therefore, the fixing member 157 is not exposed on the surface of the liquid jet head 1 in the Z1 direction, specifically on the nozzle surface SN side. On the other hand, a part of the fixing member 157 is exposed on the surface 606 of the holder 6 facing the Z2 direction. Since the fixing member 157 is not exposed on the nozzle surface SN side, it is possible to prevent ink mist from adhering to the fixing member 157 and solidifying. Therefore, it is possible to prevent the fixing member 157 from becoming difficult to remove from the holder 6 and the head module 2 due to the adhesion of the mist.

[0128] For example, after removing the fixing member 157 from the fixing hole 651H, a long rod-shaped member is inserted into the fixing hole 651H and the member is used to press the head module 2 in the Z1 direction. This makes it possible to easily release the head module 2 from being pressed into the holder 6. In other words, by using the fixing hole 651H as a hole for releasing the press-fit, it is possible to easily release the head module 2 from being pressed into the holder 6.

[0129] The fixing member 157 corresponds to the "first member." The fixing hole 651H corresponds to the "first fixing hole." The fixing hole 215 corresponds to the "first fixing hole."

[0130] Furthermore, the depth D66 of the fixing hole 651H is deeper than the depth D26 of the fixing hole 215. Because the depth D66 is deeper than the depth D26, it is easier to remove the flow path opening forming member 25 from the holder 6 than if the depth D66 were shallower.

[0131] 9, the multiple fixing members 155 are provided, for example, near corners of the holder 6, which has a rectangular shape when viewed in the Z1 direction. The multiple fixing members 157 are provided for each head module 2. Specifically, two fixing members 157 are provided for each head module 2. One of the two fixing members 157 is disposed in the Y1 direction of the head module 2 when viewed in the Z1 direction, and the other is disposed in the Y2 direction of the head module 2.

[0132] Each of the fixing members 155 and 157 is preferably a screw. Therefore, for example, a female thread is formed on the inner peripheral wall surface that forms each of fixing holes 651H, 652H, 215, and 503. When the fixing members 155 and 156 are screws, the cover 5 and the multiple head modules 2 can be easily released from the holder 6 by rotating and fastening the screws. When the fixing members 155 and 156 are screws, the multiple head modules 2 and the cover 5 can be attached and detached to and from the holder 6 as desired without using adhesive.

[0133] In addition, each of the fixing members 155 and 157 may be something other than a screw, and may include, for example, an L-shaped or T-shaped pin with the tip in the Z1 direction bent at a right angle and an elastic member such as a leaf spring or a coil spring, and may be configured to fix the holder 6 and the cover 5 using the elastic force of the elastic member.

[0134] In this way, the fixing member 155 may have any configuration as long as it is a member that fixes the holder 6 and the cover 5 to each other. The fixing member 157 may have any configuration as long as it is a member that fixes the holder 6 and the head module 2 to each other.

[0135] Furthermore, each of the fixing members 155 and 156 is disposed so as not to overlap the chip 20 when viewed in the Z1 direction, and so as to sandwich the sealing member 4 between itself and the chip 20.

[0136] Because fixing members 155 and 157 do not overlap chip 20 when viewed in the Z1 direction, the load generated by fixing fixing members 155 and 157 is less likely to be applied to chip 20 than if they overlap. Furthermore, by disposing sealing member 4 between fixing members 155 and 156 and chip 20 when viewed in the Z1 direction, the distance between chip 20 and fixing members 155 and 157 can be increased by the seal member 4. Therefore, the load generated by fixing fixing members 155 and 157 is less likely to be applied to chip 20.

[0137] 1-3F. Wiring board 7, relay board 70, and connector 71 As shown in FIG. 3, a wiring board 7 is provided for each head module 2. The wiring board 7 is inserted through the through-hole 25H of the chip 20 and the through-hole 20H of the flow path opening forming member 25. The wiring board 7 is bonded to the vibration plate 204. The wiring board 7 protrudes from the vibration plate 204 in the Z2 direction. The wiring board 7 is a mounting component on which a plurality of wires are formed for electrically connecting the chip 20 and the relay substrate 70. The wiring board 7 is, for example, a flexible board such as an FPC (Flexible Printed Circuit) or a COF (Chip On Film) or a rigid board. A drive signal and a reference voltage for driving the drive elements E are supplied to each drive element E from the wiring board 7.

[0138] The relay board 70 is fixed to the bottom surface of a recess 610 in the Z1-direction surface 605 of the flat plate portion 61 of the holder 6. The relay board 70 is flat and fixed to the holder 6 with an adhesive or the like. The relay board 70 is electrically connected to the control unit 91. A plurality of connectors 71 are mounted on the relay board 70. The plurality of connectors 71 are provided one-to-one with the plurality of wiring boards 7. An end of the wiring board 7, on which a plurality of terminals are provided, is detachably inserted into each connector 71. In other words, the wiring board 7 is preferably rigid so that the end of the wiring board 7 can be easily inserted into and removed from the connector 71. When the wiring board 7 is made of a flexible substrate, it is desirable to attach a rigid body to support the flexible substrate. When the end of the wiring board 7 is inserted into the connector 71, the wiring board 7 is electrically connected to the control unit 91 via the relay board 70.

[0139] The relay board 70 is electrically connected to the multiple head modules 2. The relay board 70 is arranged in the Z2 direction, which is the opposite direction to the Z1 direction, relative to the multiple head modules 2, and overlaps the multiple head modules 2 when viewed in the Z1 direction. The first positioning portion 216 is also provided on the surface of the cover 5 facing the Z2 direction. This makes it easy to attach and detach only the head module 2 to be replaced from below the holder 6 and the relay board 70. This eliminates the need to disconnect the electrical connections of head modules 2 other than the head module to be replaced, simplifying the attachment and detachment work.

[0140] Furthermore, as described above, the wiring board 7 is disposed on the bottom surface of the recess 610 of the holder 6. Therefore, it is easier to shorten the lengths of the head module 2 and the wiring board 7 compared to when the wiring board 7 is disposed on the surface 606 of the holder 6 facing the Z2 direction.

[0141] As described above, when only the head module 2 to be replaced is attached to the holder 6 from below the holder 6, the wiring board 7 moves in the Z2 direction from below the connector 71 toward the connector 71. Then, the wiring board 7 is inserted into the connector 71. This establishes an electrical connection between the wiring board 7 and the relay board 70.

[0142] 1-3F. Bush As shown in FIG. 4, a bushing 526 is disposed between the flow path opening forming member 25 and the cover 5. Although not shown in detail, for example, the bushing 526 is provided in the Y1 and Y2 directions of each flow path opening forming member 25 when viewed in the Z1 direction. Furthermore, a bushing 522 is disposed between the holder 6 and the cover 5. Although not shown in detail, for example, the bushing 522 is disposed in the shape of a rectangular frame along the outer edge of the holder 6 when viewed in the Z1 direction. Each of the bushings 526 and 522 is made of, for example, an elastic resin material. The provision of the bushings 526 and 522 can reduce the risk of ink mist or the like entering the storage space in the recess 610 of the holder 6 from outside the liquid jet head 1.

[0143] 2. Variations The first embodiment exemplified above can be modified in various ways. Specific modified aspects that can be applied to the first embodiment are exemplified below. Two or more aspects arbitrarily selected from the following examples can be combined as appropriate within a range that does not contradict each other.

[0144] 2-1. First modified example FIG. 13 is a cross-sectional view of a portion of the liquid jet head 1 of the first modified example. A fixing member 157 of the first modified example shown in FIG. 13 fixes the cover 5 in addition to the holder 6 and the head module 2. Furthermore, in the first modified example, the fixing member 155 is omitted. According to the first modified example, the number of fixing members can be reduced compared to the first embodiment. Therefore, according to the first modified example, the head module 2 can be attached and detached from the holder 6 using fewer fixing members compared to the first embodiment. Furthermore, in the first modified example, the head module 2 is not fixed to the cover 5 with adhesive, so that the cover 5 and the head module 2 can be easily attached and detached.

[0145] 2-2. Second modified example 14 is a cross-sectional view of a portion of a liquid jet head 1 according to a second modified example. In the second modified example shown in FIG. 14, the holder 6 does not have a second recess 612. In other words, the recess 610 of the holder 6 according to the second modified example does not have a stepped surface. The recess 610 is an accommodation space that accommodates the relay substrate 70.

[0146] The cover 5 of the second modified example is composed of a bottom plate portion 51 and a side wall portion 52. The bottom plate portion 51 is flat and has the same configuration as the cover 5 of the first embodiment. The side wall portion 52 is a frame-shaped portion that protrudes in the Z2 direction from the outer edge of the bottom plate portion 51. The cover 5 has a recess 510. The inside of the recess 510 forms a storage space that stores multiple head modules 2.

[0147] In this way, there are no particular limitations on the shapes of the holder 6 and the cover 5, and any shape may be used. In addition, a space for accommodating the head module 2 is formed by one or both of the holder 6 and the cover 5.

[0148] The cover 5 of the second modified example also has a flange portion 54. The flange portion 54 is the same as the flange portion 64 of the holder 6 of the first embodiment. However, the flange portion 54 is provided on the cover 5, not on the holder 6. The flange portion 54 also has a fourth positioning portion 542. The fourth positioning portion 542 has the same configuration as the fourth positioning portion 642 of the first embodiment, and is press-fitted into the third positioning portion 102 of the unit base 11.

[0149] Furthermore, for example, the head module 2 is fixed to the cover 5 with adhesive or the like, and the head module 2 can be removed from the holder 6 by removing the fixing member 155. When the head module 2 is fixed to the cover 5 with adhesive, if it is possible to separate the cover 5 and the head module 2, for example, by melting the adhesive with heat, then the head module 2 is considered to be removably fixed to the cover 5 and the head module 2.

[0150] 2-3. Third modified example Fig. 15 is a cross-sectional view of a portion of a liquid jet head 1 according to a third modified example. In the third modified example shown in Fig. 15, the cover 5 is omitted. According to the third modified example, the number of parts can be reduced compared to the first embodiment. Furthermore, because the cover 5 is omitted, the head module 2 can be attached to and detached from the holder 6 more easily compared to the first embodiment.

[0151] 2-4. Fourth Variation Figure 16 is a cross-sectional view of a portion of a liquid jet head 1 according to a fourth modified example. The liquid jet head 1 according to the fourth modified example shown in Figure 16 has a holder 8. The holder 8 has a first holder 81 and a second holder 82. The first holder 81 is the same as the holder 6 according to the first embodiment, except that the flange portion 64 is omitted.

[0152] The second holder 82 is the same as the cover 5 of the first embodiment except for the following elements. When viewed in the Z1 direction, the second holder 82 has a portion that extends further in the Y1 or Y2 direction than the first holder 81. A fourth positioning portion 824 is provided in this extending portion. The fourth positioning portion 824 has the same configuration as the fourth positioning portion 642 of the first embodiment, and is press-fitted into the third positioning portion 102 of the unit base 11.

[0153] The second holder 82 also has a plurality of fixing holes 821 and a plurality of second positioning portions 822. Two fixing holes 821 are provided for each head module 2. One of the two fixing holes 821 is located in the Y1 direction relative to the chip 20 when viewed in the Z1 direction, and the other is located in the Y2 direction. The fixing hole 821 is a hole that opens into the surface 512 of the second holder 82 that faces the Z2 direction. The fixing hole 821 can also be said to be a recess formed in the surface 512 of the second holder 82 that faces the Z2 direction. The head module 2 also has fixing holes 218H that correspond to the fixing holes 821. The fixing holes 218H are holes that penetrate the flow path opening forming member 25 of the head module 2.

[0154] Two second positioning portions 822 are provided for each head module 2. Although not shown in detail, one of the two second positioning portions 822 is located in the Y1 direction relative to the chip 20 when viewed in the Z1 direction, and the other is located in the Y2 direction. The second positioning portion 822 is a hole that opens into the surface 512 of the second holder 82 that faces the Z2 direction. The second positioning portion 822 is a recessed portion formed in the surface 512 of the second holder 82 that faces the Z2 direction, and can also be said to be a depression provided in the surface 512.

[0155] The head module 2 also has a first positioning portion 217 corresponding to the second positioning portion 822. The first positioning portion 217 is a protrusion that protrudes in the Z1 direction from a surface 251 facing the Z1 direction of the flow path opening forming member 25. The first positioning portion 217 is press-fitted into the second positioning portion 822. This positions the head module 2 with respect to the holder 8 including the second holder 82.

[0156] Furthermore, a fixing member 158 is inserted into the fixing hole 218H and the fixing hole 821 in this order. The fixing member 158 corresponds to a "first fixing member." The fixing member 158 is, for example, a screw, and a female thread is formed on the inner wall surface that forms the fixing hole 218H and the fixing hole 821. The head module 2 is fixed to the second holder 82 by inserting the fixing member 158 into the fixing hole 218H and the fixing hole 821 and fastening it with the screws. Note that the first holder 81 and the second holder 82 are fixed to each other by the fixing member 155, similar to the cover 5 and holder 6 of the first embodiment.

[0157] Furthermore, the second holder 82 of the holder 8 has a plurality of openings 5H, similar to the cover 5. Each of the plurality of head modules 2 is exposed to the outside through the plurality of openings 5H. A portion of the flow path opening forming member 25 is inserted into the opening 5H. Therefore, the second holder 82 having a plurality of openings 5H can suppress an increase in the paper gap, similar to the cover 5 of the first embodiment. Furthermore, there is no need to reduce the thickness of the second holder 82 in order to suppress an increase in the paper gap. Therefore, a decrease in the rigidity of the second holder 82 can be suppressed.

[0158] 2-5. Fifth Variation 17 is a cross-sectional view of a portion of the liquid jet head 1 of the fifth modified example. In the fifth modified example shown in FIG. 17, the fixing holes 218H, the fixing holes 821, and the fixing members 158 are omitted, compared to the fourth modified example. In the thirteenth modified example, for example, the second holder 82 and each head module 2 are fixed with an adhesive or the like. When the second holder 82 and each head module 2 are fixed with an adhesive, if they can be separated by, for example, melting the adhesive with heat, they can be considered to be detachably fixed to the second holder 82 and each head module 2.

[0159] 2-7. 7th Variation Fig. 18 is a cross-sectional view of a portion of the liquid jet head 1 of the seventh modified example. Fig. 19 is a top view of the liquid jet head 1 of the seventh modified example. In the seventh modified example shown in Fig. 18, the positional relationship of the fixing member 157 and the sealing member 4 with respect to the chip 20 is different. The shortest distance between the fixing member 157 and the chip 20 is shorter than the shortest distance between the sealing member 4 and the chip 20.

[0160] 19, the fixing member 157 does not overlap the chip 20 when viewed in the Z1 direction, and is disposed between the chip 20 and the sealing region 4S. This arrangement makes it easier for a reaction force to occur outside the fixing member 157 when viewed from the chip 20. This makes it possible to make it difficult for the effect of the reaction force of the sealing member 4 to be transmitted particularly to the chip 20.

[0161] 2-8. Eighth Variation Fig. 20 is a cross-sectional view of a portion of the liquid jet head 1 of the eighth modified example. Fig. 21 is a top view of the liquid jet head 1 of the eighth modified example. In the sixteenth modified example shown in Figs. 20 and 21, the fixing member 157 overlaps with the chip 20 when viewed in the Z1 direction. Even when the fixing member 157 overlaps with the chip 20 when viewed in the Z1 direction, the presence of the cover 5 can suppress the reaction force of the sealing member 4 from affecting the chip 20 compared to when the cover 5 is not present.

[0162] 2-9. 9th Variation 22 is a cross-sectional view of a portion of the liquid jet head 1 of the ninth modified example. In the liquid jet head 1 of the fifth modified example shown in FIG. 22, the first positioning portion 216a is a bottomed hole that opens in the Z2 direction of the head module 2. The first positioning portion 216a is also a recess formed in the Z2 direction of the head module 2. The second positioning portion 653a is a protrusion that protrudes in the Z1 direction from the surface of the holder 6 that faces the Z1 direction. The head module 2 is positioned with respect to the holder 6 by press-fitting the second positioning portion 653a into the first positioning portion 216a.

[0163] As with the first embodiment, even with these first positioning portion 216a and second positioning portion 653a, it is possible to easily perform positioning when attaching the head module 2 to the holder 6. Furthermore, it is possible to perform highly accurate alignment of multiple head modules 2 with respect to the holder 6. Furthermore, when replacing only some of the multiple head modules 2, it is not necessary to redo the alignment of all of the head modules 2.

[0164] As shown in the first embodiment and the ninth modified example, alignment of multiple head modules 2 can be performed with high precision by the simple method of press-fitting either the second positioning portion 653 or the first positioning portion 216 into the other.

[0165] Furthermore, the fourth positioning portion 642a is a bottomed hole that opens in the Z2 direction of the flange portion 64. The fourth positioning portion 642a is also a recess, i.e., a depression, formed in the Z1 direction of the flange portion 64. Although not shown, in this case, the third positioning portion 102 is configured with a protruding pin provided on the unit base 11. The fourth positioning portion 642a is press-fitted into the third positioning portion 102, thereby enabling the liquid jet head 1 to be positioned with respect to the unit base 11. This makes it possible to improve the alignment accuracy between multiple liquid jet heads 1 using the unit base 11 as a reference.

[0166] 2-10. 10th Variation FIG. 23 is a cross-sectional view showing a sealing member 4 of a tenth modified example and its vicinity. FIG. 24 is a cross-sectional view of a portion of a liquid jet head 1 of a tenth modified example. The thickness of the sealing member 4 of a sixth modified example shown in FIG. 23 is not constant. The sealing member 4 of the sixth modified example includes a thick portion 41 and a thin portion 42. The thick portion 41 is located near the inner wall surface that forms the communication port 4H, and is thicker than the thin portion 42. The thin portion 42 is located outside the thick portion 41.

[0167] In the case of the tenth modification, the thick portion 41 of the seal member 4 has the sealing region 4S. The thick portion 41 is in contact with the flow path opening forming member 25 and the holder 6, and is sandwiched between the flow path opening forming member 25 and the holder 6.

[0168] 24, when viewed in the Z1 direction, the support region 5S includes a region S55 that is disposed between the seal region 4S and the chip 20. Therefore, the influence of the reaction force of the seal member 4 on the chip 20 can be reduced compared to when the support region 5S does not include the region S55.

[0169] The region S55 does not necessarily have to be provided. The support region 5S and the seal region 4S may completely coincide with each other in a plan view.

[0170] 2-11. 11th Variation FIG. 25 is a cross-sectional view showing a sealing member 4 of an eleventh modified example and its vicinity. The sealing member 4 of the eleventh modified example shown in FIG. 25 includes a portion that is not in contact with both the holder 6 and the flow path opening-forming member 25. The sealing member 4 of the eleventh modified example has a sealing region 4S near the communication opening 4H. Thus, depending on the shapes of the holder 6 and the flow path opening-forming member 25, the sealing member 4 may include a portion that is not in contact with both the holder 6 and the flow path opening-forming member 25 and is not sandwiched between the holder 6 and the flow path opening-forming member 25. The portion of the sealing member 4 that is not sandwiched between the holder 6 and the flow path opening-forming member 25 corresponds to the sealing region 4S.

[0171] 2-12.Other variations Furthermore, for example, the holder 6 may be formed with a dedicated through-hole for releasing the press-fit between the first positioning portion 216 and the second positioning portion 653. For example, the through-hole may be a hole that passes through the holder 6 in the insertion / removal direction of the second positioning portion 653 relative to the first positioning portion 216 and has an opening area larger than the opening area of ​​the fixing hole 651H.

[0172] In the above description, the sealing member 4 is provided for each head module 2, but the sealing member 4 may be integrated and shared by a plurality of head modules 2.

[0173] The "first positioning portion" and the "second positioning portion" are not particularly limited in configuration to the above-described embodiment and modified examples, as long as they are configured so that one is press-fitted into the other.

[0174] "Liquid ejection devices" can be used in various devices such as facsimile machines and copiers, as well as devices dedicated to printing. The uses of liquid ejection devices are not limited to printing. For example, a liquid ejection device that ejects a solution of coloring material is used as a manufacturing device for forming color filters for display devices such as liquid crystal display panels. A liquid ejection device that ejects a solution of conductive material is used as a manufacturing device for forming wiring and electrodes on relay boards. A liquid ejection device that ejects a solution of organic matter related to living organisms is used as a manufacturing device for manufacturing biochips, for example.

[0175] Although the present invention has been described above based on preferred embodiments, the present invention is not limited to the above-described embodiments. Furthermore, the configuration of each part of the present invention can be replaced with any configuration that exhibits the same function as the above-described embodiments, and any configuration can be added. [Explanation of symbols]

[0176] 1...liquid jet head, 2...head module, 3...supply flow path member, 4...sealing member, 4H...communication port, 4S...sealing area, 5...cover, 5S...support surface, 6...holder, 6R...flow path, 7...wiring board, 10...liquid jet head unit, 11...unit base, 20...chip, 20H...through hole, 25...flow path opening forming member, 25R...flow path, 61...flat plate portion, 64...flange portion, 6R...flow path, 70...relay board, 71...connector, 100...liquid jet device, 102...third positioning portion, 150...fixing member group, 155...fixing Fixing member, 157...fixing member, 158...fixing member, 201...nozzle plate, 215...fixing hole, 216...first positioning portion, 218H...fixing hole, 250...flange portion, 251H...flow path opening, 503...fixing hole, 510...recess, 610...recess, 642...fourth positioning portion, 650H...flow path opening, 651H...fixing hole, 652H...fixing hole, 653...second positioning portion, 821...fixing hole, 2511...supported surface, C...pressure chamber, E...drive element, N...nozzle, S5...support region, S50...region, S55...region, SN...nozzle surface.

Claims

1. a plurality of head modules that eject liquid in a first direction; a metal holder to which the plurality of head modules are detachably fixed; Equipped with Each of the plurality of head modules has a flow path opening forming member made of metal that defines a flow path therein and has a first positioning portion, the holder has a plurality of second positioning portions that are press-fitted into or are pressed into the plurality of first positioning portions, respectively, to position the plurality of head modules relative to the holder, a flow path opening formed in the holder for connecting to a flow path of the head module and a flow path opening formed in the flow path opening forming member of the head module for connecting to a flow path of the holder overlap when viewed in a direction in which one of the first positioning portion and the second positioning portion is press-fitted into the other. A liquid jet head characterized by:

2. the holder has a member on which both one or more flow paths communicating with the plurality of head modules and the plurality of second positioning portions are formed. The liquid jet head according to claim 1 .

3. Each of the plurality of head modules has one nozzle plate. The liquid jet head according to claim 1 .

4. the first positioning portion is provided on a surface of the flow path opening forming member facing a second direction that is a direction opposite to the first direction, the plurality of second positioning portions are arranged on a surface of the holder facing the first direction; The liquid jet head according to claim 1 .

5. the head module includes a chip that is arranged in the first direction with respect to the flow path opening forming member, the first positioning portion does not overlap the chip when viewed in the first direction; The liquid jet head according to claim 4 .

6. the holder has a recess having the surface on which the plurality of second positioning portions are arranged as a bottom surface, a cover that is fixed to the outer peripheral wall of the recess so as to come into contact with the outer peripheral wall and has a plurality of openings for exposing each of the plurality of head modules to the outside; The liquid jet head according to claim 4 .

7. the holder includes a common flow path member having one or more flow paths communicating with the plurality of head modules, the common flow path member is disposed in a second direction that is an opposite direction to the first direction with respect to the plurality of head modules, and overlaps the plurality of head modules when viewed in the first direction, the first positioning portion is provided on a surface of the flow path opening forming member facing the second direction; The liquid jet head according to claim 1 .

8. a relay substrate electrically connected to the plurality of head modules; the relay substrate is disposed in a second direction that is an opposite direction to the first direction with respect to the plurality of head modules, and overlaps the plurality of head modules when viewed in the first direction, the first positioning portion is provided on a surface of the flow path opening forming member facing the second direction; The liquid jet head according to claim 1 .

9. the first positioning portion is disposed on a surface of the flow path opening forming member facing the first direction, the second positioning portion is disposed on a surface of the holder facing a second direction that is a direction opposite to the first direction, the holder has a plurality of openings for exposing each of the plurality of head modules to the outside, a portion of the flow path opening forming member is inserted into the opening of the holder; The liquid jet head according to claim 1 .

10. a plurality of first fixing members that detachably fix each of the plurality of head modules to the holder; the holder has a first fixing hole penetrating in the first direction, the flow path opening forming member has a recessed first fixing hole having a bottom surface, the plurality of second positioning portions are arranged on a surface of the holder facing the first direction, the first positioning portion is provided on a surface of the flow path opening forming member facing a second direction that is a direction opposite to the first direction, The first fixing member is inserted into the first fixing hole and the second fixing hole in this order in the first direction. The liquid jet head according to claim 1 .

11. The depth of the first fixing hole is deeper than the depth of the second fixing hole. The liquid jet head according to claim 10 .

12. The first fixing member is a screw. The liquid jet head according to claim 10 .

13. A plurality of the liquid jet heads according to claim 1 ; a unit base for holding the plurality of liquid jet heads; A liquid ejection device comprising:

14. the holder has a fourth positioning portion that is press-fitted into or is press-fitted into one of a plurality of third positioning portions provided on a unit base that holds the plurality of liquid jet heads, thereby positioning the liquid jet head with respect to the unit base; The liquid jet head according to claim 1 .

15. A plurality of the liquid jet heads according to claim 14; a unit base including the plurality of third positioning portions and holding the plurality of liquid jet heads; A liquid ejection device comprising:

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