Liquid jet head and liquid jet device

Abstract

To provide a liquid jet head in which jet failure from a nozzle is suppressed.SOLUTION: A liquid jet head includes: a first head chip 44 including a first nozzle group and a first common liquid chamber part communicating with the first nozzle group; a second head chip 44 including a second nozzle group and a second common liquid chamber part communicating with the second nozzle group; and a flow channel structure 60 including a plurality of flow channel substrates laminated in the first direction and having a first flow channel Sa having a first common part Sa2 which communicates with the first common liquid chamber part and the second common liquid chamber part and extends in a second direction perpendicular to the first direction, and a first flexible member 113 defining a part of the first common part.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a liquid ejection head that ejects liquid from nozzles and a liquid ejection apparatus equipped with the liquid ejection head, and more particularly to an ink jet recording head and an ink jet recording apparatus that ejects ink as the liquid. [Background technology]

[0002] A liquid ejection device, typified by an inkjet recording device such as an inkjet printer or plotter, comprises a liquid ejection head that ejects liquid from a plurality of nozzles, and a flow path member in which a flow path is formed that supplies liquid to the liquid ejection head.

[0003] The liquid jet head is disclosed to have a configuration including a head chip having a first nozzle group and a first common liquid chamber portion communicating with the first nozzle group, a head chip having a second nozzle group and a second common liquid chamber portion communicating with the second nozzle group, and a flow path structure provided with a flow path having a common portion communicating with the first common liquid chamber portion and the second common liquid chamber portion (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2020-142378 Summary of the Invention [Problem to be solved by the invention]

[0005] However, since the first nozzle group and the second nozzle group are connected via a common liquid chamber, the negative pressure generated when droplets are ejected from the nozzles of either the first nozzle group or the second nozzle group may act on the other nozzle group, which may result in poor droplet ejection from the other nozzle group. [Means for solving the problem]

[0006] An aspect of the present invention that solves the above problem is a liquid jet head comprising: a first head chip including a first nozzle group and a first common liquid chamber portion that communicates with the first nozzle group; a second head chip including a second nozzle group and a second common liquid chamber portion that communicates with the second nozzle group; and a flow path structure including a plurality of flow path substrates stacked in a first direction, the flow path having a first common portion that communicates with the first common liquid chamber portion and the second common liquid chamber portion and extends in a second direction perpendicular to the first direction, and a first flexible member that defines a portion of the first common portion.

[0007] Another aspect of the present invention is a liquid ejection apparatus including the liquid ejection head according to the above aspect, and a liquid storage section that supplies liquid to the liquid ejection head. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram showing a schematic configuration of a liquid ejecting apparatus according to a first embodiment. [Figure 2] 1 is a perspective view of a liquid jet head according to a first embodiment. [Figure 3] 1 is a plan view of a liquid jet head according to a first embodiment. [Figure 4] 1 is a cross-sectional view of a liquid jet head according to a first embodiment. [Figure 5] 1 is a cross-sectional view of a head chip according to a first embodiment. [Figure 6] FIG. 2 is a plan view of a head chip according to the first embodiment. [Figure 7] 2 is a diagram showing a schematic configuration of a flow path of the liquid ejecting device according to the first embodiment. FIG. [Figure 8] 1 is a cross-sectional view of a flow path member according to a first embodiment. [Figure 9] FIG. 2 is a plan view of a flow path substrate according to the first embodiment. [Figure 10] FIG. 2 is a plan view of a flow path substrate according to the first embodiment. [Figure 11] FIG. 2 is a plan view of a flow path substrate according to the first embodiment. [Figure 12]1 is a cross-sectional view of a flow path member according to a first embodiment. [Figure 13] 1 is a cross-sectional view of a flow path member according to a first embodiment. [Figure 14] FIG. 6 is a cross-sectional view showing a flow path member according to a second embodiment. [Figure 15] FIG. 10 is a plan view of a flow path substrate according to a second embodiment. [Figure 16] FIG. 10 is a plan view of a flow path substrate according to a second embodiment. [Figure 17] FIG. 10 is a plan view of a flow path substrate according to a second embodiment. [Figure 18] FIG. 10 is a cross-sectional view showing a flow path member according to a third embodiment. [Figure 19] FIG. 10 is a plan view of a flow path substrate according to a third embodiment. [Figure 20] FIG. 10 is a plan view of a flow path substrate according to a third embodiment. [Figure 21] FIG. 10 is a plan view of a flow path substrate according to a third embodiment. [Figure 22] FIG. 10 is a cross-sectional view showing a flow path member according to a fourth embodiment. [Figure 23] FIG. 10 is a cross-sectional view showing a flow path member according to a fifth embodiment. [Figure 24] FIG. 10 is a plan view of a flow path substrate according to a fifth embodiment. [Figure 25] FIG. 10 is a plan view of a flow path substrate according to a fifth embodiment. [Figure 26] FIG. 10 is a plan view of a flow path substrate according to a fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] The present invention will be described in detail below based on embodiments. However, the following description illustrates one aspect of the present invention and can be modified as desired within the scope of the present invention. In each drawing, the same reference numerals indicate the same components, and their description will be omitted as appropriate. In each drawing, X, Y, and Z represent three spatial axes that are orthogonal to each other. In this specification, the directions along these axes are referred to as the X direction, Y direction, and Z direction. In each drawing, the direction indicated by the arrow is the positive (+) direction, and the direction opposite the arrow is the negative (-) direction. The Z direction indicates the vertical direction, the +Z direction indicates a vertically downward direction, and the -Z direction indicates a vertically upward direction. Furthermore, the directions of the three spatial axes, which are not limited to positive and negative directions, will be described as the X-axis direction, the Y-axis direction, and the Z-axis direction.

[0010] (Embodiment 1)

[0011] FIG. 1 is a diagram showing a schematic configuration of a liquid ejecting apparatus 1 of the present invention.

[0012] As shown in the figure, the liquid ejection device 1 is a so-called serial printer that includes a liquid ejection head H and prints by conveying a medium S in the X-axis direction while moving the liquid ejection head H back and forth in the Y-axis direction and ejecting (also called discharging) liquid from the liquid ejection head H toward the medium S in the +Z direction. Note that the medium S can be made of any material, such as recording paper, resin film, cloth, etc.

[0013] The liquid ejecting device 1 includes a liquid ejecting head H, a liquid storage unit 3, a control unit 4, a transport mechanism 5 that feeds out the medium S, and a moving mechanism 6.

[0014] The liquid jet head H jets the liquid supplied from the liquid storage section 3 in the form of droplets in the +Z direction.

[0015] The liquid storage unit 3 stores the liquid to be ejected from the liquid ejection head H. Examples of the liquid storage unit 3 include a cartridge that is detachable from the liquid ejection device 1, a bag-shaped ink pack made of flexible film, and an ink tank that can be refilled with ink. The liquid storage unit 3 includes a first liquid container 3A and a second liquid container 3B. The first liquid container 3A stores a first ink, and the second liquid container 3B stores a second ink. The first ink and the second ink are inks that are different in color, composition, etc., for example. Note that the first ink and the second ink may be the same type of ink.

[0016] A supply tube TAin and a discharge tube TAout are connected to the first liquid container 3A. A supply tube TBin and a discharge tube TBout are connected to the second liquid container 3B. When there is no need to distinguish between the supply tube TAin, the discharge tube TAout, the supply tube TBin, and the discharge tube TBout, they will all be referred to as tubes.

[0017] The supply tube TAin and the supply tube TBin are tubes that supply the first ink in the first liquid container 3A and the second ink in the second liquid container 3B, which are kept at a predetermined pressure by the pump 7, to the liquid jet head H. The discharge tube TAout and the discharge tube TBout are tubes that recover the first ink and the second ink recovered from the liquid jet head H into the first liquid container 3A and the second liquid container 3B, respectively.

[0018] Although not specifically shown, the liquid storage unit 3 may be divided into a main tank and a sub-tank. The sub-tank may be connected to the liquid ejection head H, and the liquid consumed by ejecting droplets from the liquid ejection head H may be replenished from the main tank to the sub-tank.

[0019] The control unit 4 includes, for example, a control device such as a CPU (Central Processing Unit) or an FPGA (Field Programmable Gate Array), and a storage device such as a semiconductor memory. The control unit 4 also includes a power supply device that supplies power from an external power source such as a commercial power source to each element of the liquid ejection device 1. The control unit 4 is electrically connected to the liquid ejection head H via external wiring (not shown). The control unit 4 comprehensively controls each element of the liquid ejection device 1 by the control device executing a program stored in the storage device.

[0020] The transport mechanism 5 transports the medium S in the X-axis direction, and includes, for example, a transport roller 5a that is rotated by a transport motor that is driven under the control of the control unit 4.

[0021] The movement mechanism 6 is a mechanism for reciprocating the liquid jet head H in the Y-axis direction, and includes a holder 6a that holds the liquid jet head H, and a conveyor belt 6b that is an endless belt that is installed along the Y-axis direction. The control unit 4 controls the driving of a conveyor motor (not shown) to rotate the conveyor belt 6b, and moves the liquid jet head H back and forth in the Y-axis direction together with the holder 6a fixed to the conveyor belt 6b. Note that the liquid storage unit 3 can also be mounted on the holder 6a together with the liquid jet head H. The holder 6a holds one liquid jet head H, but the holder 6a may hold two or more liquid jet heads H.

[0022] The liquid jet head H performs a jetting operation in which ink supplied from the liquid storage unit 3 is jetted as droplets in the +Z direction from each of the multiple nozzles N (see FIG. 5) under the control of the control unit 4. The control unit 4 functions as a jetting control unit that controls the jetting of ink by the liquid jet head H. This jetting operation by the liquid jet head H is performed in parallel with the transport of the medium S in the X-axis direction by the transport mechanism 5 and the reciprocating movement of the liquid jet head H in the Y-axis direction by the movement mechanism 6, thereby applying ink to the medium S, or so-called printing.

[0023] Fig. 2 is a perspective view of the liquid jet head H according to embodiment 1. Fig. 3 is a plan view of the liquid jet head H as seen in the -Z direction. Fig. 4 is a cross-sectional view taken along line AA' in Fig. 3.

[0024] 2 to 4, the liquid jet head H includes a plurality of head chips 44 each having a nozzle N for ejecting ink droplets, a holder 30 for holding the head chips 44, a flow path member 60 for supplying ink to the head chips 44, a connector 75 to which wiring for transmitting and receiving control signals and the like is connected to the head chip 44, and a cover member 65 for accommodating the flow path member 60 therein. In this embodiment, one liquid jet head H includes two head chips 44. The two head chips 44 are arranged side by side in the Y-axis direction. Note that the number of head chips 44 included in one liquid jet head H may be three or more.

[0025] In this embodiment, of the two head chips 44 arranged side by side in the Y-axis direction, one located in the +Y direction relative to the other head chip 44 is referred to as head chip 44A, and the other located in the -Y direction relative to head chip 44A is referred to as head chip 44B. When there is no need to distinguish between head chips 44A and 44B, they are referred to as head chip 44.

[0026] Fig. 5 is a cross-sectional view of the head chip 44 according to the first embodiment. Fig. 6 is a plan view of the head chip 44 as viewed in the +Z direction. Fig. 7 is a diagram illustrating a schematic configuration of the flow paths of the liquid ejecting device 1. Note that the directions of the head chip 44 will be described based on the directions when the head chip 44 is mounted on the liquid ejecting head H, i.e., the X-axis direction, the Y-axis direction, and the Z-axis direction. Further, in the following description of the configuration common to the head chips 44A and 44B, the head chip 44 will be described as the head chip 44, but the configurations unique to the head chips 44A and 44B will be described as the head chips 44A and 44B.

[0027] As shown in Figure 5, the head chip 44 of this embodiment is a structure in which a pressure chamber substrate 482, a vibration plate 483, a piezoelectric actuator 484, a case portion 485, and a protective substrate 486 are arranged in the -Z direction of a flow path forming substrate 481, and a nozzle plate 487 and a head chip compliance substrate 488 are arranged on the +Z direction side of the flow path forming substrate 481.

[0028] The flow path forming substrate 481, the pressure chamber substrate 482, and the nozzle plate 487 are formed, for example, from a flat silicon plate, and the case portion 485 is formed, for example, by injection molding of a resin material. A plurality of nozzles N are formed in the nozzle plate 487. The surface of the nozzle plate 487 opposite to the flow path forming substrate 481 forms a nozzle surface.

[0029] An opening 481A and communication flow paths 481B and 481C, which are throttle flow paths, are formed in the flow path forming substrate 481. Communication flow paths 481B and 481C are through holes formed for each nozzle N, and opening 481A is an opening that continues across multiple nozzles N. Head chip compliance substrate 488 is made of a flat plate material that is placed on the surface of flow path forming substrate 481 opposite to pressure chamber substrate 482 and closes opening 481A. Pressure fluctuations within opening 481A are absorbed by flexible deformation of head chip compliance substrate 488.

[0030] A common liquid chamber SR that communicates with the opening 481A of the flow path forming substrate 481 is formed in the case portion 485. As shown in Fig. 6, the common liquid chamber SR is a space that stores ink to be supplied to the plurality of nozzles N, and is provided continuously across the plurality of nozzles N. Furthermore, as shown in Figs. 6 and 7, the case portion 485 is provided with an inlet Rin through which ink is supplied from the upstream side to the common liquid chamber SR, and an outlet Rout through which ink is discharged from the common liquid chamber SR to the downstream side. The inlet Rin will be described in detail later, but is connected to supply path connecting portions PAin and PBin of the flow path member 60 via a first supply path Sa and a second supply path Sb, and the outlet Rout is connected to discharge path connecting portions PAout and PBout of the flow path member 60 via a first discharge path Da and a second discharge path Db.

[0031] 3, the head chip 44 is provided with a nozzle row in which nozzles N are arranged in the X-axis direction. The head chip 44 is also provided with a plurality of nozzle rows in the Y-axis direction (two rows in this embodiment), in which nozzles N are arranged in the X-axis direction. Of the two nozzle rows provided on one head chip 44, one arranged in the +Y direction is referred to as nozzle row La, and the other arranged in the -Y direction is referred to as nozzle row Lb. In this embodiment, the nozzle row La and the nozzle row Lb are collectively referred to as nozzle row L. The nozzles N of these two nozzle rows La and Lb may be positioned at the same position in the X-axis direction, i.e., overlapping when viewed in the Y-axis direction. Alternatively, the nozzle row Lb may be shifted by half the pitch of the nozzles N in the X-axis direction relative to the nozzle row La. In this embodiment, the nozzle row La of head chip 44A may be referred to as nozzle row La1, the nozzle row Lb of head chip 44A may be referred to as nozzle row Lb1, the nozzle row La of head chip 44B may be referred to as nozzle row La2, and the nozzle row Lb of head chip 44B may be referred to as nozzle row Lb2.

[0032] A common liquid chamber SR is provided for each of the nozzle rows La and Lb. In other words, two common liquid chambers SR are provided on one head chip 44. In this embodiment, the common liquid chamber SR communicating with the plurality of nozzles N constituting the nozzle row La1 will be referred to as the common liquid chamber SRa1, the common liquid chamber SR communicating with the plurality of nozzles N constituting the nozzle row Lb1 will be referred to as the common liquid chamber SRb1, the common liquid chamber SR communicating with the plurality of nozzles N constituting the nozzle row La2 will be referred to as the common liquid chamber SRa2, and the common liquid chamber SR communicating with the plurality of nozzles N constituting the nozzle row Lb2 will be referred to as the common liquid chamber SRb2. Furthermore, when there is no distinction between the common liquid chamber SRa1 and the common liquid chamber SRa2, the common liquid chamber SR communicating with the nozzle row La will be referred to as the common liquid chamber SRa, and when there is no distinction between the common liquid chamber SRb1 and the common liquid chamber SRb2, the common liquid chamber SR communicating with the nozzle row Lb will be referred to as the common liquid chamber SRb.

[0033] As shown in FIG. 5, an opening 482A is formed in the pressure chamber substrate 482 of the head chip 44 for each nozzle N. The vibration plate 483 is an elastically deformable flat plate material that is installed on the surface of the pressure chamber substrate 482 opposite to the flow path forming substrate 481. The space inside each opening 482A of the pressure chamber substrate 482, sandwiched between the vibration plate 483 and the flow path forming substrate 481, functions as a pressure chamber SC that is filled with ink supplied from the common liquid chamber SR via a communicating flow path 481B. Each pressure chamber SC communicates with the nozzle N via a communicating flow path 481C in the flow path forming substrate 481. The communicating flow path 481B, the pressure chamber SC, and the communicating flow path 481C form an individual flow path 481D (see FIG. 6) that individually connects the common liquid chamber SR with one nozzle N.

[0034] A piezoelectric actuator 484 is formed for each nozzle N on the surface of the vibration plate 483 opposite the pressure chamber substrate 482. Each piezoelectric actuator 484 is also called a piezoelectric element, and is a driving element in which a piezoelectric body is interposed between opposing electrodes. The piezoelectric actuator 484 deforms based on a drive signal to vibrate the vibration plate 483, thereby varying the pressure of the ink in the pressure chamber SC, causing the ink in the pressure chamber SC to be ejected from the nozzle N. In addition, a protective substrate 486 protects the multiple piezoelectric actuators 484.

[0035] 4, a plurality of such head chips 44 (two in this embodiment) are provided in one liquid jet head H. These two head chips 44 are held by a common holder 30 of the liquid jet head H.

[0036] Holder 30 has a recessed accommodation portion 31 that opens to a surface facing the +Z direction. Head chips 44 are accommodated in accommodation portion 31. Accommodation portion 31 is provided independently for each head chip 44.

[0037] The holder 30 is provided with a plurality of communication paths 34 that allow ink to circulate between the head chip 44 and the flow path member 60. One end of each of the communication paths 34 opens to the bottom surface of the storage section 31, i.e., the surface of the storage section 31 facing the -Z direction, and communicates with each of the two inlets Rin and two outlets Rout of the head chip 44. Therefore, four communication paths 34 are provided per head chip 44. The other end of each communication path 34 opens to the surface of the holder 30 facing the -Z direction, and communicates with the first supply path Sa, the second supply path Sb, the first discharge path Da, and the second discharge path Db of the flow path member 60, which will be described in detail later. Here, as shown in Figures 4 to 7, each inlet port Rin communicating with each common liquid chamber SRa of the two head chips 44 will be referred to as an inlet port Rin_a, each outlet port Rout communicating with each common liquid chamber SRa of the two head chips 44 will be referred to as an outlet port Rout_a, each inlet port Rin communicating with each common liquid chamber SRb of the two head chips 44 will be referred to as an inlet port Rin_b, and each outlet port Rout communicating with each common liquid chamber SRb of the two head chips 44 will be referred to as an outlet port Rout_b.

[0038] Furthermore, a fixed plate 36 is fixed to the surface of the holder 30 facing the +Z direction. The fixed plate 36 is made of a metal plate such as stainless steel, and is large enough to cover the opening of the storage section 31. The fixed plate 36 is a common member fixed to the surfaces of multiple head chips 44 facing the +Z direction. The fixed plate 36 is provided with an exposure opening 37 that exposes the nozzles N of the head chip 44 in the +Z direction, independently for each head chip 44. Ink is ejected in the +Z direction from the nozzles N exposed from the exposure opening 37.

[0039] That is, head chip 44 is housed in a space formed by housing portion 31 and fixing plate 36, and nozzle N is exposed from exposure opening 37. Incidentally, housing portion 31 may be provided in common for a plurality of head chips 44.

[0040] Fig. 8 is a cross-sectional view of a flow path member 60 according to embodiment 1. Fig. 9 is a plan view of a flow path substrate 83 as viewed in the +Z direction. Fig. 10 is a plan view of a flow path substrate 84 as viewed in the +Z direction. Fig. 11 is a plan view of a flow path substrate 85 as viewed in the +Z direction. Fig. 12 is a cross-sectional view taken along line BB' in Figs. 8 to 11. Fig. 13 is a cross-sectional view taken along line CC' in Figs. 8 to 11. Note that in Fig. 9, the region in which flexible members 133 and 143 are arranged is indicated by a dashed line, and in Fig. 11, flexible members 113 and 123 are illustrated by hatching whose peripheries are surrounded by a dashed line.

[0041] The flow path member 60 is a member in which a flow path is formed that supplies ink to the head chip 44. As described above, the head chip 44 of this embodiment has two common liquid chambers SR, and each of the common liquid chambers SR is provided with an inlet Rin and an outlet Rout, so that two types of ink are supplied to, discharged from, and circulated through the head chip 44. Therefore, the flow path member 60 is provided with a first supply path Sa and a second supply path Sb to which the two types of ink are supplied, and a first discharge path Da and a second discharge path Db from which the two types of ink are discharged.

[0042] A cylindrical supply path connection portion PAin, a supply path connection portion PBin, a discharge path connection portion PAout, and a discharge path connection portion PBout that protrude in the -Z direction are provided on the surface of the flow path member 60 facing the -Z direction. A first inlet portion Sa1 that is a part of the first supply path Sa is provided inside the supply path connection portion PAin, and a second inlet portion Sb1 that is a part of the second supply path Sb is provided inside the supply path connection portion PBin. Furthermore, a first outlet portion Da1 that is a part of the first discharge path Da is provided inside the discharge path connection portion PAout, and a second outlet portion Db1 that is a part of the second discharge path Db is provided inside the discharge path connection portion PBout.

[0043] Tubes can be connected to or removed from each of the supply path connectors PAin and PBin and the discharge path connectors PAout and PBout. A supply tube TAin is connected to the supply path connector PAin, and a supply tube TBin is connected to the supply path connector PBi. A discharge tube TAout is connected to the discharge path connector PAout, and a discharge tube TBout is connected to the discharge path connector PBout.

[0044] 7, ink in the first liquid container 3A is pressurized to a predetermined pressure by the pump 7 and supplied to the first supply channel Sa via the supply tube TAin and the supply channel connection part PAin. The ink then branches off at the first supply channel Sa and passes through the communication channel 34 of the holder 30 to be supplied to each of the inlet ports Rin_a of the two head chips 44. Ink discharged from each of the outlet ports Rout_a of the two head chips 44 passes through the communication channel 34 of the holder 30, joins at the first discharge channel Da, and is returned to the first liquid container 3A via the discharge channel connection part PAout and the discharge tube TAout. The first liquid container 3A, the supply tube TAin, the supply channel connection part PAin, the discharge channel connection part PAout, and the discharge tube TAout are configured to maintain each of the nozzles N of the two head chips 44 at a predetermined range of negative pressure.

[0045] The ink in the second liquid container 3B is pressurized to a predetermined pressure by the pump 7 and supplied to the second supply path Sb via the supply tube TBin and the supply path connection part PBin. The ink then branches off at the second supply path Sb, passes through the connecting path 34, and is supplied to each of the inlet ports Rin_b of the two head chips 44. The ink discharged from each of the outlet ports Rout_b of the two head chips 44 passes through the connecting path 34, joins at the second discharge path Db, and is returned to the second liquid container 3B via the discharge path connection part PBout and the discharge tube TBout. Similar to the first liquid container 3A, the second liquid container 3B, supply tube TBin, supply path connection part PBin, discharge path connection part PBout, and discharge tube TBout are configured to maintain the nozzles N of the two head chips 44 at a predetermined range of negative pressure.

[0046] As described above, holder 30 is provided with communicating passages 34 through which ink flows, and holder 30 also functions as a flow passage member. Of course, the flow passages of flow passage member 60 may be directly connected to the flow passages of head chip 44 without providing flow passages such as communicating passages 34 in holder 30. In other words, a protrusion that protrudes in the +Z direction and has a flow passage provided therein may be provided on the surface of flow passage member 60 facing the +Z direction, and the protrusion may be inserted through holder 30 to be connected to head chip 44.

[0047] Specifically, the flow path member 60 includes a plurality of flow path substrates stacked in the Z-axis direction, five flow path substrates in this embodiment. In this embodiment, the five flow path substrates, that is, flow path substrate 81, flow path substrate 82, flow path substrate 83, flow path substrate 84, and flow path substrate 85, are stacked in this order toward the +Z direction. In addition, in a plan view looking toward the +Z direction, the outer shapes of the flow path substrates 81 to 85 are approximately the same.

[0048] A first supply path Sa, a second supply path Sb, a first discharge path Da, and a second discharge path Db are provided inside the flow path member 60. In the flow path member 60, different types of ink are supplied to the first supply path Sa and the second supply path Sb, respectively.

[0049] The first supply path Sa includes a first introduction section Sa1, a first supply common section Sa2 communicating with the first introduction section Sa1 and extending in the Y-axis direction, and two first introduction port connection sections Sa3 communicating with the first supply common section Sa2.

[0050] The first introduction part Sa1 is a flow path provided in the flow path substrates 81 to 83, and is formed by a flow path extending in the Z-axis direction, etc. One end of the first introduction part Sa1 opens to the tip of the supply path connection part PAin. In addition, at the stacking interface of the flow path substrates 82 and 83 of the first introduction part Sa1, a first liquid reservoir part Sa1a and a second liquid reservoir part Sa1b, each having a wider inner diameter than other areas, are provided, along with a filter F arranged to separate them. The filter F captures foreign matter contained in the ink, such as dust and air bubbles.

[0051] The first supply common portion Sa2 is defined by a first supply common portion recess 110 having a concave shape that opens on the surface of the flow path substrate 83 facing the +Z direction, and a first supply common portion through-hole 111 that penetrates the flow path substrate 84 in the Z axis direction. The first supply common portion recess 110 and the first supply common portion through-hole 111 have approximately the same size when viewed in the Z axis direction and are arranged in an overlapping position. The first supply common portion Sa2 defined by the first supply common portion recess 110 and the first supply common portion through-hole 111 extends in the Y axis direction. Here, the first supply common portion Sa2 extending in the Y axis direction includes having a shape that is long in the Y axis direction and short in the X axis direction when viewed in the Z axis direction. Furthermore, the first supply common portion Sa2 extending in the Y axis direction includes ink flowing along the Y axis direction within the first supply common portion Sa2. The same applies to a second supply common part Sb2, a first discharge common part Da2, and a second discharge common part Db2, which will be described later. The other end of the first introduction part Sa1 communicates with the bottom surface of the recess 110 for the first supply common part.

[0052] The first inlet connection parts Sa3 are flow paths that connect the first supply common part Sa2 and the inlets Rin_a of each head chip 44, and in this embodiment, two first inlet connection parts Sa3 are provided, which is the same number as the head chips 44. The first inlet connection parts Sa3 are provided so as to penetrate the flow path substrate 85 along the Z-axis direction. One end of the first inlet connection part Sa3 is connected to the first supply common part Sa2, and the other end is connected to the connecting passage 34.

[0053] The first supply path Sa takes in ink from the first inlet portion Sa1, and the ink that passes through the filter F is supplied to the first supply common portion Sa2. The ink supplied to the first supply common portion Sa2 is supplied to the inlets Rin_a of the two head chips 44 from the two first inlet connection portions Sa3 via the communicating passages 34.

[0054] That is, the first common supply portion Sa2 is a flow path that commonly communicates with the common liquid chamber SRa1 of the head chip 44A and the common liquid chamber SRa2 of the head chip 44B.

[0055] The flow path substrate 85 is also provided with a recess 112 that opens to a surface facing the -Z direction. The recess 112 is disposed at a position facing the first supply common portion Sa2 in the Z-axis direction. A flexible member 113 is disposed at the lamination interface between the flow path substrates 84 and 85 so as to separate the first supply common portion Sa2 from the recess 112. The flexible member 113 is a thin, flexible member formed of a material such as resin or metal that has high durability against the ink flowing through the first supply path Sa. Flexible members other than the flexible member 113 provided in the flow path member 60, which will be described later, may also be made of the same material as the flexible member 113. The flexible member 113 defines a portion of the surface of the first supply common portion Sa2 facing the +Z direction. The opening of the surface of the recess 112 facing the -Z direction is covered by the flexible member 113, thereby defining a compliance space 114. Here, the term "compliance space" refers to a space in which gas exists to displace the flexible member, and is not a liquid chamber through which liquid flows. The compliance space 114 is preferably open to the atmosphere via an air-opening path (not shown). Of course, other compliance spaces (described below) provided in the flow path member 60, other than the compliance space 114, are also preferably open to the atmosphere via air-opening paths (not shown). As shown in FIGS. 11 and 12 , the flow path substrate 85 has a protrusion 115 protruding in the −Z direction from the bottom surface of the recess 112. The protrusion 115 is disposed inside the inner circumferential surface of the recess 112 as viewed in the +Z-axis direction, and a through-hole penetrating the protrusion 115 in the Z-axis direction is formed to define a portion of the first inlet connection Sa3. The flexible member 113 is also laminated on the surface of the protrusion 115 facing the −Z direction, and a through-hole is formed in the flexible member 113 at a position overlapping the first inlet connection Sa3 as viewed in the Z-axis direction so as not to block the first inlet connection Sa3.

[0056] In this way, by providing a first supply common section Sa2 in the first supply path Sa, defining a portion of the first supply common section Sa2 with a flexible member 113, and providing a compliance space 114, the pressure fluctuations of the ink in the first supply common section Sa2 can be absorbed by the deformation of the flexible member 113, thereby reducing the pressure fluctuations of the ink in the first supply path Sa.

[0057] The second supply path Sb has a configuration similar to that of the first supply path Sa. Specifically, the second supply path Sb includes a second introduction portion Sb1, a second common supply portion Sb2 that communicates with the second introduction portion Sb1 and extends in the Y-axis direction, and two second introduction port connections Sb3 that communicate with the second common supply portion Sb2.

[0058] The second introduction part Sb1 is a flow path provided in the flow path substrates 81 to 83, and is formed by a flow path extending in the Z-axis direction, etc. One end of the second introduction part Sb1 opens to the tip of the supply path connection part PBin. In addition, at the stacking interface of the flow path substrates 82 and 83 of the second introduction part Sb1, a third liquid reservoir part Sb1a and a fourth liquid reservoir part Sb1b, each having a wider inner diameter than other regions, are provided, and a filter F is arranged to separate them.

[0059] The second supply common portion Sb2 is defined by a second supply common portion recess 120 having a recessed shape opening on the surface of the flow path substrate 83 facing the +Z direction, and a second supply common portion through portion 121 provided to penetrate the flow path substrate 84 in the Z axis direction. The second supply common portion recess 120 and the second supply common portion through portion 121 have approximately the same size when viewed in the Z axis direction and are arranged in an overlapping position. Such a second supply common portion Sb2 extends in the Y axis direction. The other end of the second introduction portion Sb1 communicates with the bottom surface of the second supply common portion recess 120.

[0060] The second inlet connection parts Sb3 are flow paths that connect the second supply common part Sb2 and the inlets Rin_b of each head chip 44, and in this embodiment, two second inlet connection parts Sb3 are provided, which is the same number as the head chips 44. The second inlet connection parts Sb3 are provided so as to penetrate the flow path substrate 85 along the Z-axis direction. One end of the second inlet connection part Sb3 is connected to the second supply common part Sb2, and the other end is connected to the connecting passage 34.

[0061] The second supply path Sb takes in ink from the second inlet portion Sb1, and the ink that passes through the filter F is supplied to the second common supply portion Sb2. The ink supplied to the second common supply portion Sb2 is supplied to the inlets Rin_b of the two head chips 44 from the two second inlet connection portions Sb3 via the communication passages 34.

[0062] That is, the second common supply portion Sb2 is a flow path that commonly communicates with the common liquid chamber SRb1 of the head chip 44A and the common liquid chamber SRb2 of the head chip 44B.

[0063] The flow path substrate 85 also has a recess 122 that opens to the surface facing the -Z direction. The recess 122 is positioned opposite the second supply common portion Sb2 in the Z-axis direction. A flexible member 123 is provided at the stacking interface between the flow path substrates 84 and 85, and is arranged to separate the second supply common portion Sb2 from the recess 122. The flexible member 123 defines a portion of the surface of the second supply common portion Sb2 facing the +Z direction. The opening of the surface of the recess 122 facing the -Z direction is covered by the flexible member 123, thereby defining a compliance space 124. As shown in FIG. 11 , the flow path substrate 85 also has a protrusion 125 that protrudes in the -Z direction from the bottom surface of the recess 122. The protrusion 125 is positioned inside the inner circumferential surface of the recess 122 when viewed in the +Z-axis direction, and a through-hole that penetrates in the Z-axis direction is formed to define a portion of the second inlet connection portion Sb3. The flexible member 123 is also laminated on the surface of the convex portion 125 facing the -Z direction, and a through hole is formed in the flexible member 123 at a position that overlaps with the second inlet connection portion Sb3 when viewed in the Z-axis direction so as not to block the second inlet connection portion Sb3.

[0064] In addition, in this embodiment, flexible members 113 and 123 are provided at the same lamination interface, so one common member is used. In other words, one flexible member serves as both flexible members 113 and 123. This reduces the number of parts, lowers costs, and simplifies assembly work. Of course, flexible members 113 and 123 may be formed from separate members.

[0065] In this way, by providing a second supply common section Sb2 in the second supply path Sb, defining a portion of the second supply common section Sb2 with a flexible member 123, and providing a compliance space 124, the pressure fluctuations of the ink in the second supply common section Sb2 can be absorbed by the deformation of the flexible member 123, thereby reducing the pressure fluctuations of the ink in the second supply path Sb.

[0066] The first discharge path Da includes a first outlet portion Da1, a first common discharge portion Da2 communicating with the first outlet portion Da1, and two first discharge port connection portions Da3 communicating with the first common discharge portion Da2.

[0067] The first outlet portion Da1 is a flow path provided in the flow path substrates 81 to 83, and is formed as a flow path extending in the Z-axis direction. One end of the first outlet portion Da1 opens to the tip of the discharge path connecting portion PAout. The other end of the first outlet portion Da1 opens to a surface of the flow path substrate 83 facing the +Z direction, and communicates with the first discharge common portion Da2. As shown in FIG. 7, a check valve 70 may be provided midway through the first outlet portion Da1 to regulate the flow of ink from the outside toward the inside of the liquid jet head H. Note that a check valve 70 may also be provided midway through the second outlet portion Db1, which will be described later.

[0068] The first discharge common part Da2 is defined by a first discharge common part recess 130 having a concave shape that opens on the surface of the flow path substrate 85 facing the -Z direction, and a first discharge common part through part 131 that is provided so as to penetrate the flow path substrate 84 in the Z axis direction. The first discharge common part recess 130 and the first discharge common part through part 131 have approximately the same size when viewed in the Z axis direction and are arranged in overlapping positions. The first discharge common part Da2 defined by the first discharge common part recess 130 and the first discharge common part through part 131 extends in the Y axis direction.

[0069] The first outlet connection parts Da3 are flow paths that connect the first outlet common part Da2 and the outlets Rout_a of each head chip 44, and in this embodiment, two first outlet connection parts Da3 are provided, which is the same number as the head chips 44. One end of the first outlet connection parts Da3 is connected to the bottom surface of the first outlet common part recess 130, and the other end is provided so as to open on the surface of the flow path substrate 85 that faces the +Z direction.

[0070] In the first discharge path Da, ink discharged from the discharge port Rout_a of the head chip 44 flows into the first discharge common part Da2 via the communication path 34 and the first discharge port connection part Da3. The ink that has flowed into the first discharge common part Da2 is discharged to the outside via the first lead-out part Da1.

[0071] That is, the first discharge common portion Da2 is a flow path that commonly communicates with the common liquid chamber SRa1 of the head chip 44A and the common liquid chamber SRa2 of the head chip 44B.

[0072] The flow path substrate 83 is also provided with a recess 132 that opens onto a surface facing the +Z direction. The recess 132 is disposed at a position facing the first discharge common portion Da2 in the Z axis direction. The recess 132 is also disposed at a position that does not overlap with the first lead-out portion Da1 when viewed in the Z axis direction. A flexible member 133 is disposed at the lamination interface between the flow path substrates 83 and 84 so as to separate the first discharge common portion Da2 and the recess 132. The flexible member 133 defines a part of the surface of the first discharge common portion Da2 facing the -Z direction. The opening of the surface of the recess 132 facing the +Z direction is covered by the flexible member 133, thereby defining a compliance space 134.

[0073] In this way, by providing a first discharge common section Da2 in the first discharge path Da, defining a portion of the first discharge common section Da2 with a flexible member 133, and providing a compliance space 134, the pressure fluctuations of the ink in the first discharge common section Da2 can be absorbed by the deformation of the flexible member 133, thereby reducing the pressure fluctuations of the ink in the first discharge path Da.

[0074] The second discharge passage Db has a configuration similar to that of the first discharge passage Da. Specifically, the second discharge passage Db includes a second outlet portion Db1, a second common discharge portion Db2 communicating with the second outlet portion Db1, and two second discharge port connection portions Db3 communicating with the second common discharge portion Db2.

[0075] The second outlet portion Db1 is a flow path provided in the flow path substrates 81 to 83 and is formed by a flow path extending in the Z-axis direction. One end of the second outlet portion Db1 opens to the tip of the discharge path connection portion PBout. The other end of the second outlet portion Db1 opens to the surface of the flow path substrate 83 facing the +Z direction and communicates with the second discharge common portion Db2.

[0076] The second discharge common part Db2 is defined by a second discharge common part through-hole 141 that penetrates the flow path substrate 84 in the Z-axis direction, and a second discharge common part recess 140 that has a concave shape that opens on the surface of the flow path substrate 84 facing the -Z direction. The second discharge common part recess 140 and the second discharge common part through-hole 141 have approximately the same size when viewed in the Z-axis direction and are arranged in an overlapping position. The second discharge common part Db2 defined by the second discharge common part recess 140 and the second discharge common part through-hole 141 extends in the Y-axis direction.

[0077] The second outlet connection parts Db3 are flow paths that connect the second outlet common part Db2 and the outlets Rout_b of each head chip 44, and in this embodiment, two are provided, the same number as the head chips 44. The second outlet connection parts Db3 have one end that communicates with the bottom surface of the second outlet common part recess 140, and the other end that opens into the surface of the flow path substrate 85 that faces the +Z direction.

[0078] In the second discharge path Db, ink discharged from the discharge port Rout_b of the head chip 44 flows into the second discharge common part Db2 via the communication path 34 and the second discharge port connection part Db3. The ink that has flowed into the second discharge common part Db2 is discharged to the outside via the second lead-out part Db1.

[0079] That is, the second discharge common portion Db2 is a flow path that commonly communicates with the common liquid chamber SRb1 of the head chip 44A and the common liquid chamber SRb2 of the head chip 44B.

[0080] The flow path substrate 83 is also provided with a recess 142 that opens to a surface facing the +Z direction. The recess 142 is disposed at a position facing the second discharge common portion Db2 in the Z-axis direction. The recess 142 is also disposed at a position that does not overlap with the second lead-out portion Db1 when viewed in the Z-axis direction. A flexible member 143 is disposed at the stacking interface between the flow path substrates 83 and 84 so as to separate the second discharge common portion Db2 and the recess 142. The flexible member 143 defines a portion of the surface of the second discharge common portion Db2 facing the -Z direction. The opening of the surface of the recess 142 facing the +Z direction is covered by the flexible member 143, thereby defining a compliance space 144. In this embodiment, the flexible members 133 and 143 are provided at the same stacking interface, and therefore a single common member is used. In other words, a single flexible member serves as both the flexible members 133 and 143. This reduces the number of parts, thereby reducing costs and simplifying the assembly process. Of course, flexible member 133 and flexible member 143 may be formed as separate members.

[0081] In this way, by providing a second discharge common section Db2 in the second discharge path Db, defining a portion of the second discharge common section Db2 with a flexible member 143, and providing a compliance space 144, the pressure fluctuations of the ink in the second discharge common section Db2 can be absorbed by the deformation of the flexible member 143, thereby reducing the pressure fluctuations of the ink in the second discharge path Db.

[0082] The first supply common portion Sa2, the second supply common portion Sb2, the first discharge common portion Da2, and the second discharge common portion Db2 are arranged at positions that do not overlap one another when viewed in the Z-axis direction. That is, when viewed in the Z-axis direction, the compliance space 114 does not overlap the second supply common portion Sb2, the first discharge common portion Da2, and the second discharge common portion Db2, and the compliance space 124 does not overlap the first supply common portion Sa2, the first discharge common portion Da2, and the second discharge common portion Db2. Similarly, when viewed in the Z-axis direction, the compliance space 134 does not overlap the first supply common portion Sa2, the second supply common portion Sb2, and the first discharge common portion Da2, and the compliance space 144 does not overlap the first supply common portion Sa2, the second supply common portion Sb2, and the second discharge common portion Db2. In this embodiment, the compliance spaces 114 and 124 are defined by the recesses 112 and 122 of the flow path substrate 85, on which the recesses 132 and 142 that define portions of the first and second discharge common portions Da2 and Db2 are formed. That is, the recesses that define the compliance spaces are formed in the substrate that defines the common portions of the flow paths. Therefore, it is not necessary to provide components that define the compliance spaces separately from the components that form the flow paths. Therefore, by forming the recesses that define the compliance spaces in the substrate that defines the common portions of the flow paths, the number of components of the flow path member 60 can be reduced, thereby reducing costs and simplifying the assembly of the flow path member 60. Similarly, the compliance spaces 134 and 144 are defined by the recesses 132 and 142 that are formed in the flow path substrate 83, on which the first and second outlet portions Da1 and Db1 are formed. Therefore, it is not necessary to provide components that define the compliance spaces separately from the components that form the flow paths.

[0083] Here, when the liquid ejection device 1 performs printing, for example, ink is ejected from the two head chips 44 while the liquid ejection head H is moved in the +Y direction. At this time, the head chip 44A arranged in the +Y direction faces the medium S before the head chip 44A arranged in the -Y direction, so printing is performed by causing the head chip 44A arranged in the +Y direction in the liquid ejection head H to start ejecting ink first, and then the head chip 44B arranged in the -Y direction to start ejecting ink. At this time, when the head chip 44A starts ejecting ink, the head chip 44B has not yet ejected ink. Therefore, the negative pressure in the common liquid chamber SRa1 acts on the common liquid chamber SRa2 via a flow path common to the head chips 44A and 44B, for example, the first common supply part Sa2 that communicates with both the common liquid chamber SRa1 communicated with the nozzle row La1 and the common liquid chamber SRa2 that communicates with the nozzle row La2, which may result in ink not being ejected properly from the nozzle row La2. However, in this embodiment, by defining portions of the first supply common portion Sa2 of the first supply path Sa, the second supply common portion Sb2 of the second supply path Sb, the first discharge common portion Da2 of the first discharge path Da, and the second discharge common portion Db2 of the second discharge path Db, which are flow paths that are commonly connected to two head chips 44, with flexible members 113, 123, 133, and 143, negative pressure generated in the flow paths can be absorbed by deforming the flexible members 113 to 143. Therefore, even when multiple head chips 44 that start ejecting ink at different times are provided, as described above, it is possible to prevent negative pressure in one head chip 44 from acting on negative pressure in another head chip 44. This reduces variation in the weight of ink ejected from each head chip 44, thereby preventing uneven shading in printed matter.

[0084] Furthermore, in this embodiment, the flexible members 113, 123 are provided as a single member common to a plurality of first supply common portions Sa2 and second supply common portions Sb2, thereby reducing the number of parts and costs, and simplifying the assembly of the flow path member 60. Similarly, the flexible members 133, 143 are provided as a single member common to a plurality of first discharge common portions Da2 and second discharge common portions Db2, thereby reducing the number of parts and costs, and simplifying the assembly of the flow path member 60.

[0085] Furthermore, since the compliance spaces 114-144 are individually defined as the first supply common portion Sa2, the second supply common portion Sb2, the first discharge common portion Da2, and the second discharge common portion Db2, the flexible members 113-143 are held down by the partition walls that separate the compliance spaces 114-144. This makes it difficult for the flexible members 113-143 to peel off from the flow path member 60, thereby preventing ink from leaking to the outside.

[0086] As shown in FIGS. 2 and 4, the flow path member 60 is housed in a cover member 65 fixed to the −Z direction side of the holder 30.

[0087] In addition, the cover member 65 has four through holes 67 on the surface on the -Z direction side, and these four through holes 67 expose the supply path connection part PAin, the supply path connection part PBin, the discharge path connection part PAout, and the discharge path connection part PBout to the outside.

[0088] 4, a relay board 73 having a connector 75 is housed inside the cover member 65. The connector 75 provided on the relay board 73 is exposed to the outside from a connection opening 63, which is a through-hole provided on the surface of the cover member 65 on the -Z direction side, and a wiring (not shown) for connecting to an external control unit 4 is connected to the connector 75. The multiple head chips 44 and the relay board 73 are electrically connected by a wiring (not shown).

[0089] In this embodiment, the Z-axis direction is an example of a "first direction," and the Y-axis direction is an example of a "second direction." The flow path member 60 is an example of a "flow path structure." In this embodiment, either one of the two head chips 44 is an example of a "first head chip," and in this case, the nozzle row L of the first head chip and the common liquid chamber SR communicating with the nozzle row L are examples of a "first nozzle group" and a "first common liquid chamber." In addition, either one of the two head chips 44 other than the first head chip is an example of a "second head chip," and the nozzle row L of the second head chip and the common liquid chamber SR communicating with the nozzle row L are examples of a "second nozzle group" and a "second common liquid chamber."

[0090] Furthermore, any one of the first supply path Sa, the second supply path Sb, the first discharge path Da, and the second discharge path Db is an example of a “first flow path,” and any one of the first supply common section Sa2, the second supply common section Sb2, the first discharge common section Da2, and the second discharge common section Db2 is an example of a “first common part.” Furthermore, any one of the first supply path Sa, the second supply path Sb, the first discharge path Da, and the second discharge path Db is an example of a “second flow path,” and any one of the first supply common section Sa2, the second supply common section Sb2, the first discharge common section Da2, and the second discharge common section Db2 is an example of a “second common part.”

[0091] Moreover, either flexible member 113 and flexible member 123 or flexible member 133 and flexible member 143 is an example of a "first flexible member," and the other is an example of a "second flexible member."

[0092] Furthermore, either or both of compliance spaces 114, 124 is an example of a "first compliance space," and either or both of compliance spaces 134, 144 is an example of a "second compliance space."

[0093] In addition, one of the flow path substrates 83 and 85 in this embodiment is an example of a "first flow path substrate," the other is an example of a "second flow path substrate," and the flow path substrate 84 is an example of a "third flow path substrate."

[0094] To give a specific example, if head chip 44A is an example of a "first head chip," head chip 44B is an example of a "second head chip," the nozzle row La1 of head chip 44A and the common liquid chamber SRa1 communicating with nozzle row La1 are an example of a "first nozzle group" and a "first common liquid chamber section," and the nozzle row La2 of head chip 44B and the common liquid chamber SRa2 communicating with nozzle row La2 are an example of a "second nozzle group" and a "second common liquid chamber section," then the first supply path Sa is an example of a "first flow path," the first supply common section Sa2 is an example of a "first common section," the first discharge path Da is an example of a "second flow path," the first discharge common section Da2 is an example of a "second common section," the flexible member 113 is an example of a "first flexible member," and the flexible member 133 is an example of a "second flexible member." Furthermore, the compliance space 114 is an example of a “first compliance space,” and the compliance space 134 is an example of a “second compliance space.” Furthermore, the flow path substrate 85 of this embodiment is an example of a “first flow path substrate,” the flow path substrate 83 is an example of a “second flow path substrate,” and the flow path substrate 84 is an example of a “third flow path substrate.”

[0095] (Embodiment 2) FIG. 14 is a cross-sectional view of a main part of a flow path member 60 according to embodiment 2 of the present invention. FIG. 15 is a plan view of a flow path substrate 83 as viewed in the +Z direction. FIG. 16 is a plan view of a flow path substrate 84 as viewed in the +Z direction. FIG. 17 is a plan view of a flow path substrate 85 as viewed in the +Z direction. In FIG. 15, the region where the flexible member 150 is arranged is indicated by a dashed line, and in FIG. 17, the flexible member 151 is illustrated by hatching with its outer periphery surrounded by a dashed line. In addition, members similar to those in the above-described embodiments are assigned the same reference numerals, and redundant explanations will be omitted. In addition, although the head chip 44 is not shown, it has the same configuration as that of embodiment 1 described above.

[0096] Similar to the first embodiment described above, the flow path member 60 includes flow path substrates 81 to 85. In addition, in a plan view looking toward the +Z direction, the flow path substrates 81 to 85 have substantially the same outer shape. The flow path member 60 also includes a first supply path Sa, a second supply path Sb, a first discharge path Da, and a second discharge path Db.

[0097] The first supply common part Sa2 has its side defined by a first supply common part through part 111 that penetrates the flow path substrate 84 in the Z-axis direction.

[0098] The second supply common part Sb2 has its side defined by a second supply common part through part 121 that penetrates the flow path substrate 84 in the Z-axis direction.

[0099] As shown in FIG. 17, the convex portions 115 and 125 of this embodiment are arranged inside the inner circumferential surface of the concave portion 154 when viewed in the +Z axis direction.

[0100] The first discharge common part Da2 has its side defined by a first discharge common part through part 131 that penetrates the flow path substrate 84 in the Z-axis direction.

[0101] 17, the flow path substrate 85 has a protrusion 137 that protrudes in the -Z direction from the bottom surface of the recess 154. The protrusion 137 is disposed inside the inner circumferential surface of the recess 154 when viewed in the +Z axis direction, and has a through-hole that penetrates in the Z axis direction to define a part of the first outlet connection portion Da3. The flexible member 151 is also laminated on the surface of the protrusion 137 facing the -Z direction, and has a through-hole formed in the flexible member 151 at a position that overlaps with the first outlet connection portion Da3 when viewed in the Z axis direction so as not to block the first outlet connection portion Da3.

[0102] The second discharge common part Db2 has its side defined by a second discharge common part through part 141 that penetrates the flow path substrate 84 in the Z-axis direction.

[0103] A portion of the -Z direction surfaces of the first supply common portion Sa2, the second supply common portion Sb2, the first discharge common portion Da2, and the second discharge common portion Db2 is defined by a flexible member 150. A portion of the +Z direction surfaces of the first supply common portion Sa2, the second supply common portion Sb2, the first discharge common portion Da2, and the second discharge common portion Db2 is defined by a flexible member 151. In other words, each of the flexible members 150 and 151 is a common member that defines a portion of the first supply common portion Sa2, the second supply common portion Sb2, the first discharge common portion Da2, and the second discharge common portion Db2.

[0104] 17, the flow path substrate 85 has a protrusion 145 that protrudes in the -Z direction from the bottom surface of the recess 154. The protrusion 145 is disposed inside the inner circumferential surface of the recess 154 when viewed in the +Z axis direction, and has a through-hole that penetrates in the Z axis direction to define a part of the second outlet connection portion Db3. The flexible member 151 is also laminated on the surface of the protrusion 145 facing the -Z direction, and a through-hole is formed in the flexible member 151 at a position that overlaps with the second outlet connection portion Db3 when viewed in the Z axis direction so as not to block the second outlet connection portion Db3.

[0105] Furthermore, a recess 152 that opens in the +Z direction is formed in the flow path substrate 83. The recess 152 is disposed at a position that overlaps the first supply common portion Sa2, the second supply common portion Sb2, the first discharge common portion Da2, and the second discharge common portion Db2 when viewed in the +Z direction. The opening of the recess 152 in the +Z direction is covered by the flexible member 150, thereby defining a compliance space 153. The compliance space 153 allows the flexible member 150 to deform in portions that define the first supply common portion Sa2, the second supply common portion Sb2, the first discharge common portion Da2, and the second discharge common portion Db2. Specifically, the portion of the flexible member 150 that closes the recess 152 is deformable in portions that overlap the first supply common portion through portion 111, the second supply common portion through portion 121, the first discharge common portion through portion 131, and the second discharge common portion through portion 141 when viewed in the Z-axis direction.

[0106] Furthermore, a recess 154 that opens in the -Z direction is formed in the flow path substrate 85. The recess 154 is disposed at a position that overlaps the first supply common portion Sa2, the second supply common portion Sb2, the first discharge common portion Da2, and the second discharge common portion Db2 when viewed in the +Z direction. The opening of the recess 154 in the +Z direction is covered by the flexible member 151, thereby defining a compliance space 155. The compliance space 155 allows the flexible member to deform in portions that define the first supply common portion Sa2, the second supply common portion Sb2, the first discharge common portion Da2, and the second discharge common portion Db2. Specifically, the portion of the flexible member 151 that closes the recess 154 is deformable in portions that overlap the first supply common portion through portion 111, the second supply common portion through portion 121, the first discharge common portion through portion 131, and the second discharge common portion through portion 141 when viewed in the Z axis direction.

[0107] The first introduction portion Sa1 communicates with a portion of the first supply common portion through portion 111 that does not overlap with the recess 152 when viewed in the Z-axis direction. The second introduction portion Sb1 communicates with the second supply common portion Sb2 at a portion of the second supply common portion through portion 121 that does not overlap with the recess 152 when viewed in the Z-axis direction. The second outlet portion Db1 communicates with a portion of the second discharge common portion through portion 141 that does not overlap with the recess 152 when viewed in the Z-axis direction. The first outlet portion Da1 communicates with a portion of the first discharge common portion through portion 131 that does not overlap with the recess 152 when viewed in the Z-axis direction. In other words, the first introduction portion Sa1, the second introduction portion Sb1, the second outlet portion Db1, and the first outlet portion Da1 open on the surface of the flow path substrate 83 that is stacked on the flow path substrate 84.

[0108] The liquid jet head H having the flow path member 60 of this embodiment has the same effects as those of the first embodiment.

[0109] Furthermore, in this embodiment, the -Z direction surface and the +Z direction surface of portions of the first supply common portion Sa2, the second supply common portion Sb2, the first discharge common portion Da2, and the second discharge common portion Db2 are defined by the flexible members 150, 151, respectively, and therefore the compliance capacity of each of the first supply common portion Sa2, the second supply common portion Sb2, the first discharge common portion Da2, and the second discharge common portion Db2 can be increased without increasing the size of the flow path member 60 in the direction perpendicular to the Z axis. Furthermore, by providing compliance spaces 153, 155 in common to the first supply common portion Sa2, the second supply common portion Sb2, the first discharge common portion Da2, and the second discharge common portion Db2, the amount of pressure fluctuation that can be absorbed can be increased.

[0110] Furthermore, in this embodiment, by using flexible members 150, 151 that commonly define the first supply common portion Sa2, the second supply common portion Sb2, the first discharge common portion Da2, and the second discharge common portion Db2, the number of parts can be reduced, reducing costs and simplifying assembly. Of course, an independent flexible member may be provided for each of the first supply common portion Sa2, the second supply common portion Sb2, the first discharge common portion Da2, and the second discharge common portion Db2, or an independent flexible member may be provided for each group consisting of two or more first supply common portions Sa2, the second supply common portion Sb2, the first discharge common portion Da2, and the second discharge common portion Db2.

[0111] In this embodiment, the Z-axis direction is an example of a "first direction," and the Y-axis direction is an example of a "second direction." The flow path member 60 is an example of a "flow path structure." In this embodiment, either one of the two head chips 44 is an example of a "first head chip," and the nozzle row L of the first head chip and the common liquid chamber SR communicating with the nozzle row L are examples of a "first nozzle group" and a "first common liquid chamber." In addition, either one of the two head chips 44 other than the first head chip is an example of a "second head chip," and the nozzle row L of the second head chip and the common liquid chamber SR communicating with the nozzle row L are examples of a "second nozzle group" and a "second common liquid chamber."

[0112] Furthermore, any one of the first supply path Sa, the second supply path Sb, the first discharge path Da, and the second discharge path Db is an example of a “first flow path,” and any one of the first supply common section Sa2, the second supply common section Sb2, the first discharge common section Da2, and the second discharge common section Db2 is an example of a “first common part.” Furthermore, any one of the first supply path Sa, the second supply path Sb, the first discharge path Da, and the second discharge path Db is an example of a “second flow path,” and any one of the first supply common section Sa2, the second supply common section Sb2, the first discharge common section Da2, and the second discharge common section Db2 is an example of a “second common part.”

[0113] Moreover, one of the flexible members 150 and 151 is an example of a "first flexible member," and the other is an example of a "second flexible member."

[0114] Furthermore, either the flexible member 150, the compliance space 153, and the flow path substrate 83, or the flexible member 151, the compliance space 155, and the flow path substrate 85 is an example of a "first flexible member," a "first compliance space," and a "first flow path substrate," and the other is an example of a "second flexible member," a "second compliance space," and a "third flow path substrate."

[0115] Moreover, the flow path substrate 84 is an example of a "third flow path substrate."

[0116] To give a specific example, if head chip 44A is an example of a "first head chip," head chip 44B is an example of a "second head chip," nozzle row La1 of head chip 44A and common liquid chamber SRa1 communicating with nozzle row La1 are an example of a "first nozzle group" and a "first common liquid chamber section," and nozzle row La2 of head chip 44B and common liquid chamber SRa2 communicating with nozzle row La2 are an example of a "second nozzle group" and a "second common liquid chamber section," then first supply path Sa is an example of a "first flow path," first supply common section Sa2 is an example of a "first common section," first discharge path Da is an example of a "second flow path," first discharge common section Da2 is an example of a "second common section," flexible member 151 is an example of a "first flexible member," and flexible member 150 is an example of a "second flexible member." Furthermore, compliance space 155 is an example of a “first compliance space,” and compliance space 153 is an example of a “second compliance space.” Furthermore, flow path substrate 85 of this embodiment is an example of a “first flow path substrate,” flow path substrate 83 is an example of a “second flow path substrate,” and flow path substrate 84 is an example of a “third flow path substrate.”

[0117] (Embodiment 3) FIG. 18 is a cross-sectional view of a main part of a flow path member according to embodiment 3 of the present invention. FIG. 19 is a plan view of flow path substrate 83 as viewed in the +Z direction. FIG. 20 is a plan view of flow path substrate 84 as viewed in the +Z direction. FIG. 21 is a plan view of flow path substrate 85 as viewed in the +Z direction. In FIG. 19, the region where flexible member 157 is arranged is indicated by a dashed line, and in FIG. 21, flexible member 158 is illustrated by hatching with its outer periphery surrounded by a dashed line. Note that members similar to those in the above-described embodiments are given the same reference numerals, and redundant explanations will be omitted. In addition, although head chip 44 is not shown, it has the same configuration as in embodiment 1 described above.

[0118] Similar to the first embodiment described above, the flow path member 60 includes flow path substrates 81 to 85. In addition, in a plan view looking toward the +Z direction, the flow path substrates 81 to 85 have substantially the same outer shape. The flow path member 60 also includes a first supply path Sa, a second supply path Sb, a first discharge path Da, and a second discharge path Db.

[0119] A portion of the +Z direction surface of each of the first supply common portion Sa2 and the second supply common portion Sb2 is defined by the flexible member 157. In other words, the flexible member 157 is a common member that defines a portion of the first supply common portion Sa2 and the second supply common portion Sb2. The flexible member 157 is held between the flow path substrates 83 and 84.

[0120] The first inlet connection portion Sa3 and the second inlet connection portion Sb3 are provided to penetrate the flow path substrates 84 and 85 in the Z-axis direction, respectively. The first inlet connection portion Sa3 communicates with the first supply common portion Sa2 via a through-hole 157a formed in the flexible member 157 at a position overlapping the first inlet connection portion Sa3. The second inlet connection portion Sb3 communicates with the second supply common portion Sb2 via a through-hole 157b formed in the flexible member 157 at a position overlapping the second inlet connection portion Sb3. A portion of the first inlet connection portion Sa3 is formed by penetrating in the Z-axis direction the interior of a protrusion 115 that protrudes in the -Z direction from the bottom surface of a first discharge common portion recess 130 (described below). A portion of the second inlet connection portion Sb3 is formed by penetrating in the Z-axis direction the interior of a protrusion 125 that protrudes in the -Z direction from the bottom surface of a second discharge common portion recess 140 (described below). The convex portions 115 and 125 have the same configuration as in the first embodiment.

[0121] The first outlet portion Da1 and the second outlet portion Db1 are each a flow path extending in the Z-axis direction formed by penetrating the flow path substrates 81 to 84. That is, the first outlet portion Da1 opens onto a surface of the flow path substrate 84 facing the +Z direction and communicates with the first discharge common portion Da2. The second outlet portion Db1 opens onto a surface of the flow path substrate 84 facing the +Z direction and communicates with the second discharge common portion Db2.

[0122] The first discharge common portion Da2 is defined by a first discharge common portion recess 130 having a recessed shape that opens on the surface facing the -Z direction of the flow path substrate 85. The second discharge common portion Db2 is defined by a second discharge common portion recess 140 having a recessed shape that opens on the surface facing the -Z direction of the flow path substrate 85. The first discharge common portion Da2 and the second discharge common portion Db2 each extend in the Y-axis direction.

[0123] The first discharge common portion Da2 is disposed at a position where it at least partially overlaps with the first supply common portion Sa2 when viewed in the Z-axis direction. Therefore, the flow path member 60 can be made smaller along the XY plane than when the first supply common portion Sa2 and the first discharge common portion Da2 are disposed side by side in the XY plane defined by the X-axis and Y-axis directions.

[0124] The second discharge common portion Db2 is disposed at a position where it at least partially overlaps with the second supply common portion Sb2 when viewed in the Z-axis direction. This allows the flow path member 60 to be made smaller along the XY plane than when the second supply common portion Sb2 and the second discharge common portion Db2 are disposed side by side in the XY plane defined by the X-axis and Y-axis directions.

[0125] Furthermore, a portion of the -Z direction surface of each of the first discharge common portion Da2 and the second discharge common portion Db2 is defined by the flexible member 158. In other words, the flexible member 158 is a common member that defines a portion of the first supply common portion Sa2, the first discharge common portion Da2, and the second discharge common portion Db2. The flexible member 158 is held between the flow path substrates 84 and 85.

[0126] Each of the first outlet connection portion Da3 and the second outlet connection portion Db3 is formed by penetrating the flow path substrate 85 in the Z-axis direction.

[0127] The flow path substrate 84 is provided with a first through-hole 159 penetrating in the Z-axis direction at a position overlapping the first supply common section Sa2 and the first discharge common section Da2 when viewed in the Z-axis direction, and a second through-hole 161 penetrating in the Z-axis direction at a position overlapping the second supply common section Sb2 and the second discharge common section Db2 when viewed in the Z-axis direction.

[0128] The openings of the first through portion 159 and the second through portion 161 in the -Z direction are covered by the flexible member 157, and the openings of the first through portion 159 and the second through portion 161 in the +Z direction are covered by the flexible member 158. As a result, a compliance space 160 is defined inside the first through portion 159, and a compliance space 162 is defined inside the second through portion 161. By providing the compliance space 160 in this manner, the portion of the flexible member 157 that defines the first supply common portion Sa2 and the portion of the flexible member 158 that defines the first discharge common portion Da2 are deformable. In other words, the flexible members 157 and 158 define the compliance space 160 that is common to the first supply common portion Sa2 and the first discharge common portion Da2. Furthermore, by providing the compliance space 162, the portion of the flexible member 157 that defines the second supply common portion Sb2 and the portion of the flexible member 158 that defines the second discharge common portion Db2 are deformable. In other words, the flexible members 157 and 158 define the compliance space 162 that is common to the second supply common portion Sb2 and the second discharge common portion Db2.

[0129] The liquid jet head H having the flow path member 60 of this embodiment also achieves the same effects as those of the above-described embodiment.

[0130] Furthermore, since one space serves as the compliance space for deforming flexible members 157 and 158, flow path member 60 can be made smaller in size in the Z-axis direction than when separate compliance spaces are provided for each.

[0131] Furthermore, by arranging the first supply common section Sa2 and the first discharge common section Da2 in a position where they overlap in the Z-axis direction, and by arranging the second supply common section Sb2 and the second discharge common section Db2 in a position where they overlap in the Z-axis direction, the flow path member 60 can be made smaller in the XY plane compared to when any two of them are arranged side by side in the XY plane.

[0132] Furthermore, in this embodiment, by providing the compliance spaces 160, 162 individually, the partitions between them can hold the flexible members 157, 158 between the flow path substrate 83 and the flow path substrate 85. Therefore, separation due to deformation of the flexible members 157, 158 can be suppressed, and leakage of ink can be suppressed.

[0133] In this embodiment, the compliance spaces 160, 162 are provided separately, but this is not particularly limited, and the compliance spaces 160, 162 may be connected to each other. This prevents the flexible members 157, 158 facing the compliance spaces 160, 162 from being pressed down by the partition wall separating them, thereby increasing the compliance capacity.

[0134] 21, in this embodiment, the positions at which the inlet Rin and the outlet Rout are arranged relative to the common liquid chamber SR are different. For example, a pair of a first inlet connection portion Sa3 and a first outlet connection portion Da3 aligned in the X-axis direction communicate with an inlet Rin_a and an outlet Rout_a, respectively, which communicate with the same common liquid chamber SRa, and a pair of a second inlet connection portion Sb3 and a second outlet connection portion Db3 aligned in the X-axis direction communicate with an inlet Rin_b and an outlet Rout_b, respectively, which communicate with the same common liquid chamber SRb.

[0135] In this embodiment, the Z-axis direction is an example of a "first direction," and the Y-axis direction is an example of a "second direction." The flow path member 60 is an example of a "flow path structure." In this embodiment, either one of the two head chips 44 is an example of a "first head chip," and the nozzle row L of the first head chip and the common liquid chamber SR communicating with the nozzle row L are examples of a "first nozzle group" and a "first common liquid chamber portion."

[0136] Furthermore, any one of the two head chips 44 other than the first head chip is an example of a "second head chip," and the nozzle row L of the second head chip and the common liquid chamber SR connected to the nozzle row L are examples of a "second nozzle group" and a "second common liquid chamber section."

[0137] Furthermore, the first supply path Sa and the first discharge path Da are an example of a "first flow path" and a "second flow path", and the second supply path Sb and the second discharge path Db are an example of a "first flow path" and a "second flow path". Furthermore, the first supply common part Sa2 and the first discharge common part Da2 are an example of a "first common part" and a "second common part", and the second supply common part Sb2 and the second discharge common part Db2 are an example of a "first common part" and a "second common part".

[0138] Either flexible member 157 or 158 is an example of a "first flexible member," and the other is an example of a "second flexible member."

[0139] Also, either one of the compliance spaces 160, 162 is an example of a "common first compliance space."

[0140] Furthermore, either the flow path substrate 83 or the flow path substrate 85 is an example of a "first flow path substrate," the other is an example of a "second flow path substrate," and the flow path substrate 84 is an example of a "third flow path substrate."

[0141] Specifically, if head chip 44A is an example of a "first head chip," head chip 44B is an example of a "second head chip," nozzle row La1 of head chip 44A and common liquid chamber SRa1 communicating with nozzle row La1 are examples of a "first nozzle group" and a "first common liquid chamber portion," and nozzle row La2 of head chip 44B and common liquid chamber SRa2 communicating with nozzle row La2 are examples of a "second nozzle group" and a "second common liquid chamber portion," then first supply path Sa is an example of a "first flow path," first supply common portion Sa2 is an example of a "first common portion," first discharge path Da is an example of a "second flow path," first discharge common portion Da2 is an example of a "second common portion," flexible member 157 is an example of a "first flexible member," and flexible member 158 is an example of a "second flexible member." Furthermore, compliance space 160 is an example of a "common first compliance space." Furthermore, the flow path substrate 83 of this embodiment is an example of a "first flow path substrate," the flow path substrate 85 is an example of a "second flow path substrate," and the flow path substrate 84 is an example of a "third flow path substrate."

[0142] (Embodiment 4) 22 is a cross-sectional view of a main part of a flow path member 60 according to the fourth embodiment of the present invention. Note that the same components as those in the above-described embodiments are given the same reference numerals, and redundant explanations will be omitted. Also, although the head chip 44 is not shown, it has the same configuration as that in the first embodiment.

[0143] As shown in the figure, the flow path member 60 of this embodiment includes flow path substrates 81 to 87. The flow path member 60 also includes a first supply path Sa, a second supply path Sb, a first discharge path Da, and a second discharge path Db.

[0144] The first supply path Sa includes a first introduction portion Sa1, a first supply common portion Sa2 communicating with the first introduction portion Sa1, and two first introduction port connections Sa3 communicating with the first supply common portion Sa2.

[0145] The first introduction portion Sa1 is the same as that in the third embodiment described above, and therefore a duplicated description will be omitted.

[0146] The first supply common portion Sa2 is defined by a first supply common portion first recess 135a having a recessed shape opening on the surface facing the +Z direction of the flow path substrate 83, and a first supply common second recess 135b having a recessed shape opening on the surface facing the -Z direction of the flow path substrate 84. The first supply common portion Sa2 extends in the Y-axis direction.

[0147] The first inlet connection parts Sa3 are flow paths that connect the first supply common part Sa2 and the inlets Rin_a of each head chip 44, and in this embodiment, two first inlet connection parts Sa3 are provided, which is the same number as the head chips 44. The first inlet connection parts Sa3 are flow paths provided in the flow path substrates 84 to 87, and are formed by flow paths extending in the Z-axis direction or flow paths extending along the lamination interface of each stacked flow path substrate. One end of the first inlet connection part Sa3 is connected to the first supply common part Sa2, and the other end is connected to the inlet Rin_a via a communication path 34 (not shown).

[0148] The second supply path Sb has the same configuration as the first supply path Sa. Specifically, the second supply path Sb includes a second introduction part Sb1, a second common supply part Sb2 communicating with the second introduction part Sb1, and two second introduction port connections Sb3 communicating with the second common supply part Sb2.

[0149] The second introduction portion Sb1 is the same as that in the third embodiment described above, except that one end opens into the bottom surface of the second common supply portion first recess 136a of the flow path substrate 84, and therefore a duplicated description will be omitted.

[0150] The second supply common portion Sb2 is defined by a second supply common portion first recess 136a having a recessed shape opening on the surface facing the +Z direction of the flow path substrate 84, and a second supply common portion second recess 136b having a recessed shape opening on the surface facing the -Z direction of the flow path substrate 85. The second supply common portion Sb2 extends in the Y-axis direction.

[0151] The second inlet connection parts Sb3 are flow paths that connect the second supply common part Sb2 and the inlets Rin_b of each head chip 44, and in this embodiment, two are provided, the same number as the head chips 44. The second inlet connection parts Sb3 are flow paths provided in the flow path substrates 85 to 87, and are formed by flow paths extending in the Z-axis direction or flow paths extending along the lamination interface of each stacked flow path substrate. One end of the second inlet connection part Sb3 is connected to the second supply common part Sb2, and the other end is connected to the inlet Rin_b via a communication path 34 (not shown).

[0152] The first discharge path Da includes a first outlet portion Da1, a first common discharge portion Da2 communicating with the first outlet portion Da1, and two first discharge port connection portions Da3 communicating with the first common discharge portion Da2.

[0153] The first outlet portion Da1 is a flow path provided in the flow path substrates 81 to 85, and is formed by a flow path extending in the Z-axis direction, a flow path extending along the lamination interface of the stacked flow path substrates, etc. One end of the first outlet portion Da1 opens to the tip of the discharge path connecting portion PAout.

[0154] The first discharge common portion Da2 is defined by a first discharge common portion recess 130 having a recessed shape that opens to the surface facing the +Z direction of the flow path substrate 85. The first discharge common portion Da2 extends in the Y-axis direction.

[0155] A part of the surface of the first discharge common part Da2 in the +Z direction is defined by a flexible member 163. The flexible member 163 is held between the flow path substrates 85 and 86. The other end of the first lead-out part Da1 communicates with the bottom surface of the first discharge common part recess 130.

[0156] The first discharge port connection portions Da3 are flow paths that connect the first discharge common portion Da2 and the discharge ports Rout_a of each head chip 44, and in this embodiment, two first discharge port connection portions Da3 are provided, the same number as the head chips 44. The first discharge port connection portions Da3 are provided on the flow path substrates 86 and 87. One end of the first discharge port connection portion Da3 communicates with the first discharge common portion Da2 in a portion not defined by the flexible member 163 of the first discharge common portion Da2, that is, in a portion defined by the flow path substrate 86 of the first discharge common portion Da2. The other end of the first discharge port connection portion Da3 communicates with the discharge port Rout_a via a communication path 34 (not shown).

[0157] The second discharge path Db includes a second outlet portion Db1, a second common discharge portion Db2 communicating with the second outlet portion Db1, and two second discharge port connection portions Db3 communicating with the second common discharge portion Db2.

[0158] The second outlet portion Db1 is a flow path provided in the flow path substrates 81 to 86, and is formed by a flow path extending in the Z-axis direction, a flow path extending along the stacking interface of the flow path substrates, etc. One end of the second outlet portion Db1 opens to the tip of the discharge path connecting portion PBout.

[0159] The second discharge common portion Db2 is defined by a second discharge common portion recess 140 having a recessed shape that opens to the surface facing the -Z direction of the flow path substrate 87. The second discharge common portion Db2 extends in the Y-axis direction.

[0160] A portion of the −Z direction surface of the second discharge common part Db2 is defined by a flexible member 164. The flexible member 164 is held between the flow path substrates 86 and 87. The other end of the second lead-out part Db1 communicates with the second discharge common part Db2 at a portion of the second discharge common part Db2 that is not defined by the flexible member 164, that is, at a portion of the second discharge common part Db2 that is defined by the flow path substrate 86.

[0161] The second outlet connection parts Db3 are flow paths that connect the second outlet common part Db2 and the outlets Rout_b of each head chip 44, and in this embodiment, two second outlet connection parts Db3 are provided, which is the same number as the head chips 44. The second outlet connection parts Db3 are provided on the flow path substrate 87. One end of the second outlet connection parts Db3 communicates with the second outlet common part Db2, and the other end communicates with the outlet Rout_b via a communication path 34 (not shown).

[0162] Furthermore, the flow path substrate 86 is provided with a third through portion 165 that penetrates in the Z-axis direction at a position that overlaps with the first discharge common portion Da2 and the second discharge common portion Db2 when viewed in the Z-axis direction. The opening of the third through portion 165 in the -Z direction is covered by a flexible member 163, and the opening of the third through portion 165 in the +Z direction is covered by a flexible member 164. This defines a compliance space 166 inside the third through portion 165. By providing the compliance space 166, the portion of the flexible member 163 that defines the first discharge common portion Da2 and the portion of the flexible member 164 that defines the second discharge common portion Db2 are deformable.

[0163] The liquid jet head H having the flow path member 60 of this embodiment can achieve the same effects as the above-described embodiment.

[0164] In FIG. 22, a filter F is provided in the first inlet portion Sa1. However, instead, a filter may be provided midway between each of the two first inlet connection portions Sa3. Similarly, instead of the filter F in the second inlet portion Sb1, a filter may be provided midway between each of the two second inlet connection portions Sb3. In such a case, negative pressure from one head chip 44 is more likely to act on the other head chip via the first discharge path Da and the second discharge path Db rather than the first supply path Sa and the second supply path Sb. For this reason, by defining a portion of the first discharge common portion Da2 and the second discharge common portion Db2, which are common portions of the first discharge path Da and the second discharge path Db, with a flexible member, pressure fluctuations within these first discharge common portion Da2 and second discharge common portion Db2 can be absorbed by deforming the flexible member, thereby more effectively reducing pressure fluctuations.

[0165] In this embodiment, the first supply common portion Sa2, the second supply common portion Sb2, the first discharge common portion Da2, and the second discharge common portion Db2 are arranged at positions that overlap when viewed in the Z-axis direction. Therefore, the flow path member 60 can be made smaller along the XY plane than when the first supply common portion Sa2, the second supply common portion Sb2, the first discharge common portion Da2, and the second discharge common portion Db2 are arranged along the XY plane.

[0166] Furthermore, one compliance space 166 serves as both the compliance space for deformation of flexible member 163 and the compliance space for deformation of flexible member 164. This allows for a reduction in size of flow path member 60 in the Z-axis direction compared to when separate compliance spaces are provided.

[0167] In this embodiment, the Z-axis direction is an example of a "first direction," and the Y-axis direction is an example of a "second direction." Also, the flow path member 60 is an example of a "flow path structure." Also, the head chip 44A is an example of a "first head chip," the head chip 44B is an example of a "second head chip," the nozzle row La1 of the head chip 44A and the common liquid chamber SRa1 communicating with the nozzle row La1 are examples of a "first nozzle group" and a "first common liquid chamber portion," the nozzle row La2 of the head chip 44B and the common liquid chamber SRa2 communicating with the nozzle row La2 are examples of a "second nozzle group" and a "second common liquid chamber portion," and the nozzle row Lb1 of the head chip 44A and the common liquid chamber SRb1 communicating with the nozzle row Lb1 are examples of a "third nozzle group." In the embodiment, the nozzle array Lb2 of the head chip 44B and the common liquid chamber SRb2 communicating with the nozzle array Lb2 are examples of a "fourth nozzle group" and a "fourth common liquid chamber portion," the first discharge path Da is an example of a "first flow path," the first discharge common portion Da2 is an example of a "first common portion," the second discharge path Db is an example of a "second flow path," the second discharge common portion Db2 is an example of a "second common portion," the flexible member 163 is an example of a "first flexible member," and the flexible member 164 is an example of a "second flexible member." Furthermore, the compliance space 166 is an example of a "common first compliance space." Furthermore, the flow path substrate 85 of the embodiment is an example of a "first flow path substrate," the flow path substrate 87 is an example of a "second flow path substrate," and the flow path substrate 86 is an example of a "third flow path substrate."

[0168] (Embodiment 5) Fig. 23 is a cross-sectional view of a main part of a flow path member 60 according to a fifth embodiment of the present invention. Fig. 24 is a plan view of a flow path substrate 81 as viewed in the +Z direction. Fig. 25 is a plan view of a flow path substrate 82 as viewed in the +Z direction. Fig. 26 is a plan view of a flow path substrate 83 as viewed in the +Z direction. Note that in Fig. 24, the region in which the flexible member 170 is arranged is indicated by a dashed line, and in Fig. 26, the flexible member 180 is illustrated by hatching whose periphery is surrounded by a dashed line. Note that the same reference numerals are used for the same members as in the above-described embodiments, and redundant explanations will be omitted.

[0169] As shown in the figure, the flow path member 60 of this embodiment includes flow path substrates 81 to 83. In addition, in a plan view looking toward the +Z direction, the flow path substrates 81 to 83 have substantially the same outer shape. The flow path member 60 also includes a first supply path Sa and a first discharge path Da.

[0170] The first supply path Sa includes a first introduction portion Sa1, a first common supply portion Sa2, and a plurality of first introduction port connections Sa3 communicating with the first common supply portion Sa2.

[0171] The first introduction part Sa1 is a flow path provided in the flow path substrate 81, and is formed by a flow path extending in the Z-axis direction. One end of the first introduction part Sa1 opens into the tip of the supply path connection part PAin.

[0172] The first supply common portion Sa2 is defined by a first supply common portion recess 110 that opens on a surface facing the +Z direction of the flow path substrate 81. The first supply common portion Sa2 extends in the X-axis direction. The other end of the first introduction portion Sa1 communicates with the bottom surface of the first supply common portion recess 110.

[0173] A part of the surface of the first common supply portion Sa2 facing the +Z direction is defined by the flexible member 170. That is, the flexible member 170 is held between the flow path substrates 81 and .

[0174] The first inlet connection parts Sa3 are flow paths that connect the first supply common part Sa2 and the inlets Rin_a of each head chip 44, and the number of the first inlet connection parts Sa3 provided is the same as the number of the head chips 44. Note that the number of the head chips 44 is not particularly limited. In this embodiment, since one liquid jet head H is provided with two head chips 44 (not shown), the number of the first inlet connection parts Sa3 provided is two, the same number as the head chips 44.

[0175] The first inlet connection part Sa3 is provided on the flow path substrates 82 and 83. One end of the first inlet connection part Sa3 communicates with the first supply common part Sa2 in a portion of the first supply common part Sa2 that is not defined by the flexible member 170, i.e., in a portion that is defined by the flow path substrate 82.

[0176] A recess 171 that opens in the -Z direction is provided in the flow path substrate 82 at a position that overlaps with the first supply common portion Sa2 when viewed in the Z axis direction. The opening of the recess 171 in the -Z direction is covered by a flexible member 170, thereby defining a compliance space 172. The compliance space 172 allows the portion of the flexible member 170 that defines the first supply common portion Sa2 to deform.

[0177] The first discharge path Da includes a first outlet portion Da1, a first common discharge portion Da2 communicating with the first outlet portion Da1, and a plurality of first discharge port connecting portions Da3 communicating with the first common discharge portion Da2.

[0178] The first outlet portion Da1 is a flow path provided in the flow path substrates 81 and 82, and is formed by a flow path extending in the Z-axis direction. One end of the first outlet portion Da1 opens to the tip of the discharge path connection portion PAout. The other end of the first outlet portion Da1 opens to a surface of the flow path substrate 82 facing the +Z direction, and communicates with the first discharge common portion Da2.

[0179] The first discharge common portion Da2 is defined by a first discharge common portion recess 130 that opens on the surface facing the -Z direction of the flow path substrate 83. The first discharge common portion Da2 extends in the X-axis direction.

[0180] Furthermore, a portion of the −Z direction surface of the first discharge common portion Da2 is defined by the flexible member 180. That is, the flexible member 180 is held between the flow path substrates 82 and 83. In this embodiment, the flexible member 180 is provided continuously across the space between the flow path substrates 82 and 83.

[0181] The first outlet connection parts Da3 are flow paths that connect the first common outlet part Da2 and the outlets Rout_a of each head chip 44, and in this embodiment, the same number of first outlet connection parts Da3 as the head chips 44 are provided. In this embodiment, one liquid jet head H is provided with two head chips 44 (not shown), and therefore the number of first outlet connection parts Da3 is two, the same number as the head chips 44. Note that in this embodiment, one head chip 44 has one common liquid chamber SR in which one inlet port Rin_a and one outlet port Rout_a communicate with each other. In other words, the head chip 44 in this embodiment has one nozzle row L.

[0182] The flow path substrate 82 is provided with a recess 181 that opens in the +Z direction at a position that overlaps with the first discharge common portion Da2 as viewed in the Z axis direction. That is, the first discharge common portion Da2 overlaps with both the recess 171 and the recess 181 as viewed in the Z axis direction. Furthermore, the first supply common portion Sa2 overlaps with both the recess 171 and the recess 181 as viewed in the Z axis direction. The opening of the recess 181 in the +Z direction is covered by the flexible member 180, thereby defining a compliance space 182. The compliance space 182 allows the portion of the flexible member 180 that defines the first discharge common portion Da2 to deform. As viewed in the Z axis direction, the compliance spaces 172 and 182 defined on the same flow path substrate 82 are arranged at positions that do not overlap with each other. Therefore, compared to when the compliance spaces 172 and 182 are provided on different substrates, the number of parts can be reduced, reducing costs and simplifying the assembly process. Furthermore, by arranging the compliance spaces 172 and 182 at positions where they do not overlap when viewed in the Z-axis direction, the flow path member 60 can be made smaller in size in the Z-axis direction compared to when they are arranged at positions where they overlap each other.

[0183] Furthermore, recess 171 that defines compliance space 172 and recess 181 that defines compliance space 182 partially overlap each other when viewed in the X-axis direction. By arranging recess 171 and recess 181 in positions where they partially overlap each other when viewed in the X-axis direction in this way, the thickness of flow path substrate 82 in the Z-axis direction can be reduced, and flow path member 60 can be made smaller in size in the Z-axis direction.

[0184] The liquid jet head H having the flow path member 60 of this embodiment has the same effects as the above-described embodiment.

[0185] Furthermore, by arranging the first supply common portion Sa2 and the first discharge common portion Da2 at positions that overlap each other when viewed in the Z-axis direction, the flow path member 60 can be made smaller in the XY plane than when both are arranged side by side in the XY plane.

[0186] Furthermore, by arranging the first supply common portion Sa2 at a position overlapping both the recessed portion 171 and the recessed portion 181 when viewed in the Z-axis direction, the flow path member 60 can be made smaller in the XY plane and the flow path cross section of the first supply common portion Sa2 can be secured relatively large. Similarly, by arranging the first discharge common portion Da2 at a position overlapping both the recessed portion 171 and the recessed portion 181 when viewed in the Z-axis direction, the flow path member 60 can be made smaller in the XY plane and the flow path cross section of the first supply common portion Sa2 can be secured relatively large.

[0187] In this embodiment, the Z-axis direction is an example of a "first direction," and the X-axis direction is an example of a "second direction." The flow path member 60 is an example of a "flow path structure." In this embodiment, either one of the two head chips 44 is an example of a "first head chip," and the nozzle row L of the first head chip and the common liquid chamber SR communicating with the nozzle row L are examples of a "first nozzle group" and a "first common liquid chamber." The other of the two head chips 44 is an example of a "second head chip," and the nozzle row L of the second head chip and the common liquid chamber SR communicating with the nozzle row L are examples of a "second nozzle group" and a "second common liquid chamber."

[0188] Furthermore, one of the first supply path Sa, the first supply common portion Sa2, the flow path substrate 81, the flexible member 170, the recess 171, and the compliance space 172, and the first discharge path Da, the first discharge common portion Da2, the flow path substrate 83, the flexible member 180, the recess 181, and the compliance space 182 is an example of a “first flow path,” a “first common portion,” a “first flow path substrate,” a “first flexible member,” a “first recess,” or a “first compliance space,” and the other is an example of a “second flow path,” a “second common portion,” a “second flow path substrate,” a “second recess,” or a “second compliance space.” Furthermore, the flow path substrate 82 is an example of a “third flow path substrate,” and one of the surface of the flow path substrate 82 facing the −Z direction and the surface facing the +Z direction is an example of a “first surface,” and the other is an example of a “second surface.”

[0189] (Other embodiments) Although the embodiments of the present invention have been described above, the basic configuration of the present invention is not limited to those described above.

[0190] In the above-described embodiments 1-3 and 5, the first supply common portion Sa2 of the first supply path Sa, the second supply common portion Sb2 of the second supply path Sb, the first discharge common portion Da2 of the first discharge path Da, and the second discharge common portion Db2 of the second discharge path Db, which are flow paths commonly connected to multiple head chips 44, are partially defined by flexible members. However, this is not particularly limited. Because the first supply path Sa and the second supply path Sb are provided with filters F, when ink is ejected from the head chip 44, pressure fluctuations are greater on the first discharge path Da and the second discharge path Db side than on the first supply path Sa and the second supply path Sb side. For this reason, it is sufficient to define at least a portion of the first discharge common portion Da2 of the first discharge path Da and the second discharge common portion Db2 of the second discharge path Db with flexible members. In other words, flexible members need not be provided to partially define the first supply common portion Sa2 of the first supply path Sa and the second supply common portion Sb2 of the second supply path Sb. Conversely, it is also possible to provide only a flexible member that defines a portion of the first supply common section Sa2 of the first supply path Sa and the second supply common section Sb2 of the second supply path Sb, and not to provide a flexible member that defines a portion of the first discharge common section Da2 of the first discharge path Da and the second discharge common section Db2 of the second discharge path Db.

[0191] Furthermore, while the head chip 44 in each of the above-described embodiments has been illustrated as having a configuration in which ink circulates through the common liquid chamber SR, this is not particularly limited. For example, the head chip 44 may have a configuration in which ink circulates through the pressure chamber SC. That is, the head chip 44 may be provided with a first common liquid chamber that communicates with one end of the pressure chamber SC and a second common liquid chamber that communicates with the other end of the pressure chamber SC, and the ink from the first common liquid chamber may be supplied to the pressure chamber SC, the ink from the pressure chamber SC may be discharged into the second common liquid chamber, and the ink may be collected from the second common liquid chamber to the outside. In this case, the first common liquid chamber and the second common liquid chamber together correspond to the "common liquid chamber portion."

[0192] The method for fixing the flexible member to the flow path member 60 in the above-described embodiment is not particularly limited, and examples thereof include adhesion with an adhesive, and welding with heat, ultrasonic waves, or the like.

[0193] For example, in the above-described embodiments, the thin-film piezoelectric actuator 484 was used as the driving element for generating a pressure change in the pressure chamber SC, but the invention is not limited to this, and the driving element can be, for example, a thick-film piezoelectric actuator formed by attaching a green sheet or the like, or a longitudinal vibration type piezoelectric actuator in which piezoelectric material and electrode forming material are alternately laminated and expanded and contracted in the axial direction. The driving element can also be a so-called electrostatic actuator in which a heating element is disposed in the pressure chamber SC and bubbles are generated by the heat generated by the heating element to eject droplets from the nozzle N, or a so-called electrostatic actuator in which static electricity is generated between a vibration plate and an electrode, and the electrostatic force deforms the vibration plate to eject droplets from the nozzle N.

[0194] Furthermore, in the above-described liquid ejection device 1, an example was given in which the liquid ejection head H is mounted on a holder 6a and moves in the main scanning direction, but this is not particularly limited to this, and the present invention can also be applied to, for example, a so-called line-type recording device in which the liquid ejection head H is fixed and printing is performed simply by moving a medium S such as paper in the sub-scanning direction.

[0195] (Addendum) From the above-described exemplary embodiments, the following configurations can be understood, for example.

[0196] A preferred embodiment of the liquid jet head according to the present invention includes: a first head chip including a first nozzle group and a first common liquid chamber communicating with the first nozzle group; a second head chip including a second nozzle group and a second common liquid chamber communicating with the second nozzle group; and a flow path structure including a plurality of flow path substrates stacked in a first direction, the flow path structure including: a first flow path having a first common portion communicating with the first common liquid chamber and the second common liquid chamber and extending in a second direction perpendicular to the first direction; and a first flexible member defining a part of the first common portion. This configuration reduces negative pressure in the first common portion generated by ejecting liquid from either the first nozzle group or the second nozzle group, thereby mitigating a water hammer effect on the other nozzle group and suppressing abnormal ejection from the other nozzle group.

[0197] In Aspect 2, which is a specific example of Aspect 1, the flow path structure includes a second flow path having a second common portion that communicates with the first common liquid chamber portion and the second common liquid chamber portion and extends in the second direction, and a second flexible member that defines a portion of the second common portion, and the plurality of flow path substrates include a first flow path substrate that defines the second common portion and, together with the first flexible member, defines a first compliance space, and a second flow path substrate that defines the first common portion and, together with the second flexible member, defines a second compliance space. This allows the flow paths and the compliance spaces to be arranged on the same flow path substrate so as not to overlap in a plan view in the first direction, thereby ensuring a large cross-sectional area of ​​the flow path and preventing the flow path structure from becoming large in size in the first direction.

[0198] In aspect 3, which is a specific example of aspect 2, the plurality of flow path substrates include a third flow path substrate disposed between the first flow path substrate and the second flow path substrate, which defines the first common portion and the second common portion.

[0199] In Aspect 4, which is a specific example of Aspect 1, the flow path structure has a second flexible member that defines a part of the first common portion, and the plurality of flow path substrates include a first flow path substrate that defines a first compliance space together with the first flexible member, a second flow path substrate that defines a second compliance space together with the second flexible member, and a third flow path substrate that is disposed between the first flow path substrate and the second flow path substrate and defines the first common portion together with the first flexible member and the second flexible member. According to this, by providing flexible members on both sides of the third flow path substrate in the first direction, a large compliance capacity can be ensured and a water hammer effect can be further reduced.

[0200] In Aspect 5, which is a specific example of Aspect 1, the flow path structure includes a second flow path having a second common portion that communicates with the first common liquid chamber portion and the second common liquid chamber portion and extends in the second direction, and a second flexible member that defines a portion of the second common portion, wherein the first common portion and the second common portion at least partially overlap each other when viewed in the first direction, and the first flexible member and the second flexible member define a common first compliance space. This allows the flow path structure to be simplified and made smaller by sharing a compliance space that serves as the compliance space for deformation of the first flexible member and the compliance space for deformation of the second flexible member.

[0201] In aspect 6, which is a specific example of aspect 5, the multiple flow path substrates include a first flow path substrate that defines the first common portion, a second flow path substrate that defines the second common portion, and a third flow path substrate that is arranged between the first flow path substrate and the second flow path substrate and that, together with the first flexible member and the second flexible member, defines the first compliance space.

[0202] In Aspect 7, which is a specific example of Aspect 1, the first head chip includes a third nozzle group and a third common liquid chamber portion communicating with the third nozzle group, and the second head chip includes a fourth nozzle group and a fourth common liquid chamber portion communicating with the fourth nozzle group, the flow path structure includes a third flow path having a third common portion communicating with the third common liquid chamber portion and the fourth common liquid chamber portion and extending in the second direction, and a second flexible member defining a portion of the third common portion, and the plurality of flow path substrates include a first flow path substrate defining the first common portion, a second flow path substrate defining the third common portion, and a third flow path substrate disposed between the first flow path substrate and the second flow path substrate and defining a first compliance space together with the first flexible member and the second flexible member. This allows the structure to be simplified and made smaller by sharing the compliance spaces of the first common portion and the third common portion.

[0203] In aspect 8, which is a specific example of aspect 7, the first flow path is a flow path that recovers liquid from the first common liquid chamber portion and the second common liquid chamber portion, and the third flow path is a flow path that recovers liquid from the third common liquid chamber portion and the fourth common liquid chamber portion.

[0204] In Aspect 9, which is a specific example of Aspect 1, the flow path structure includes a second flow path having a second common portion that communicates with the first common liquid chamber portion and the second common liquid chamber portion and extends in the second direction, and a second flexible member that defines a portion of the second common portion, and the plurality of flow path substrates include a first flow path substrate that defines the first common portion, a second flow path substrate that defines the second common portion, and a third flow path substrate disposed between the first flow path substrate and the second flow path substrate, the third flow path substrate having a first surface that has a first recess that defines a first compliance space between itself and the first flexible member, and a second surface opposite to the first surface that has a second recess that defines a second compliance space between itself and the second flexible member. In this manner, the first recess and the second recess for defining the compliance space are formed on both sides of the third flow path substrate in the first direction, thereby reducing the number of parts and achieving miniaturization.

[0205] In Aspect 10, which is a specific example of Aspect 9, the first recess and the second recess partially overlap each other when viewed in the second direction, which allows the flow path structure to be made smaller in size in the first direction.

[0206] In Aspect 11, which is a specific example of Aspect 10, the first common portion overlaps both the first recess and the second recess as viewed in the first direction. This allows the flow path structure to be miniaturized in a direction perpendicular to the first direction, while ensuring a large flow path cross-sectional area.

[0207] In aspect 12, which is a specific example of aspects 2, 5, and 9, the first flow path is a flow path that supplies liquid to the first common liquid chamber section and the second common liquid chamber section, and the second flow path is a flow path that recovers liquid from the first common liquid chamber section and the second common liquid chamber section.

[0208] A liquid ejection device according to a preferred aspect 13 includes the liquid ejection head according to the above aspect 1, and a liquid storage unit that supplies liquid to the liquid ejection head. This can improve print quality by suppressing abnormal ejection of droplets from the nozzle groups. [Explanation of symbols]

[0209] 1...liquid ejection device, 3...liquid storage section, 3A...first liquid container, 3B...second liquid container, TAin...supply tube, TAout...discharge tube, TBin...supply tube, TBout...discharge tube, 4...control section, 5...transport mechanism, 5a...transport roller, 6...movement mechanism, 7...pump, H...liquid ejection head, 30...holder, 31...storage section, 34...communicating passage, 60...flow path member, 63...connection opening, 65...cover member, 81-88...flow path substrate, Da...first discharge path, Da1...first lead-out section, Da2...first discharge common section, Da3...first discharge port connection section, Db...second discharge path, Db1... Second outlet portion, Db2...second exhaust common portion, Db3...second exhaust port connection portion, F...filter, PAin...supply path connection portion, PAout...discharge path connection portion, PBin...supply path connection portion, PBout...discharge path connection portion, S...medium, Sa...first supply path, Sa1...first introduction portion, Sa2...first supply common portion, Sa3...first introduction port connection portion, Sb...second supply path, Sb1...second introduction portion, Sb2...second supply common portion, Sb3...second introduction port connection portion, 110...recess for first supply common portion, 111...penetration portion for first supply common portion, 112...recess, 113...flexible member, 114...compliance space, 120... Recess for second supply common part, 121...through portion for second supply common part, 122...recess, 123...flexible member, 124...compliance space, 130...recess for first discharge common part, 131...through portion for first discharge common part, 132...recess, 133...flexible member, 134...compliance space, 135a...first recess for first supply common part, 136a...first recess for second supply common part, 135b...second recess for first supply common part, 136b...second recess for second supply common part, 140...recess for second discharge common part, 141...through portion for second discharge common part, 142...recess, 143...flexible member, 144...compliance space compliance space, 150...flexible member, 151...flexible member, 152...recess, 153...compliance space, 154...recess, 155...compliance space, 157...flexible member, 158...flexible member, 159...first through-portion, 160...compliance space, 161...second through-portion, 162...compliance space, 163...flexible member, 164...flexible member, 165...third through-portion, 166...compliance space, 170...flexible member, 171...recess, 172...compliance space, 180...flexible member, 181...recess, 182...compliance space,44...head chip, 481...flow path forming substrate, SC...pressure chamber, SR...common liquid chamber, 482...pressure chamber substrate, 483...vibration plate, 484...piezoelectric actuator, 485...case part, 486...protective substrate, 487...nozzle plate, 488...head chip compliance substrate, L, La, Lb...nozzle array, N...nozzle, Rin...inlet, Rout...outlet.

Claims

1. a first head chip including a first nozzle group and a first common liquid chamber portion communicating with the first nozzle group; a second head chip including a second nozzle group and a second common liquid chamber portion communicating with the second nozzle group; a flow path structure including a plurality of flow path substrates stacked in a first direction, the flow path structure having a first flow path having a first common portion that communicates with the first common liquid chamber portion and the second common liquid chamber portion and extends in a second direction perpendicular to the first direction, and a first flexible member that defines a part of the first common portion; A liquid jet head comprising:

2. the flow path structure includes a second flow path having a second common portion that communicates with the first common liquid chamber portion and the second common liquid chamber portion and extends in the second direction, and a second flexible member that defines a part of the second common portion; The plurality of flow path substrates include: a first flow path substrate defining the second common portion and defining a first compliance space together with the first flexible member; a second flow path substrate defining the first common portion and defining a second compliance space together with the second flexible member; The liquid jet head according to claim 1 .

3. the plurality of flow path substrates include a third flow path substrate disposed between the first flow path substrate and the second flow path substrate and defining the first common portion and the second common portion; The liquid jet head according to claim 2 .

4. the flow path structure includes a second flexible member that defines a portion of the first common portion; The plurality of flow path substrates include: a first flow path substrate defining a first compliance space together with the first flexible member; a second flow path substrate defining a second compliance space together with the second flexible member; a third flow path substrate disposed between the first flow path substrate and the second flow path substrate, and defining the first common portion together with the first flexible member and the second flexible member; The liquid jet head according to claim 1 .

5. the flow path structure includes a second flow path having a second common portion that communicates with the first common liquid chamber portion and the second common liquid chamber portion and extends in the second direction, and a second flexible member that defines a part of the second common portion; the first common portion and the second common portion at least partially overlap each other when viewed in the first direction; the first flexible member and the second flexible member define a common first compliance space; The liquid jet head according to claim 1 .

6. The plurality of flow path substrates include: a first flow path substrate defining the first common portion; a second flow path substrate defining the second common portion; a third flow path substrate disposed between the first flow path substrate and the second flow path substrate, and defining the first compliance space together with the first flexible member and the second flexible member; The liquid jet head according to claim 5 .

7. the first head chip includes a third nozzle group and a third common liquid chamber portion communicating with the third nozzle group, the second head chip includes a fourth nozzle group and a fourth common liquid chamber portion communicating with the fourth nozzle group, Equipped with the flow path structure includes a third flow path having a third common portion that communicates with the third common liquid chamber portion and the fourth common liquid chamber portion and extends in the second direction, and a second flexible member that defines a part of the third common portion; The plurality of flow path substrates include: a first flow path substrate defining the first common portion; a second flow path substrate defining the third common portion; a third flow path substrate disposed between the first flow path substrate and the second flow path substrate, and defining a first compliance space together with the first flexible member and the second flexible member; The liquid jet head according to claim 1 .

8. the first flow path is a flow path that recovers liquid from the first common liquid chamber and the second common liquid chamber, the third flow path is a flow path for recovering liquid from the third common liquid chamber and the fourth common liquid chamber; The liquid jet head according to claim 7 .

9. the flow path structure includes a second flow path having a second common portion that communicates with the first common liquid chamber portion and the second common liquid chamber portion and extends in the second direction, and a second flexible member that defines a part of the second common portion; The plurality of flow path substrates include: a first flow path substrate defining the first common portion; a second flow path substrate defining the second common portion; a third flow path substrate disposed between the first flow path substrate and the second flow path substrate, The third flow path substrate has a first surface having a first recess that defines a first compliance space between the first flexible member and the first surface, and a second surface that is a surface opposite to the first surface and has a second recess that defines a second compliance space between the second flexible member and the second surface. The liquid jet head according to claim 1 .

10. The first recess and the second recess partially overlap each other when viewed in the second direction. The liquid jet head according to claim 9 .

11. the first common portion overlaps both the first recess and the second recess when viewed in the first direction; The liquid jet head according to claim 10 .

12. the first flow path is a flow path that supplies liquid to the first common liquid chamber and the second common liquid chamber, the second flow path is a flow path that recovers liquid from the first common liquid chamber and the second common liquid chamber.

10. The liquid jet head according to claim 2, 5 or 9.

13. The liquid jet head according to claim 1 ; a liquid storage unit that supplies liquid to the liquid jet head; A liquid ejection device comprising:

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