Liquid ejection head and liquid ejection device

Abstract

The liquid ejection head and the liquid ejection device of the present invention reduce the generation of structural crosstalk while suppressing an increase in flow path resistance. The liquid ejection head of the present invention is characterized by including: a first pressure chamber that extends in a first direction and applies pressure to the liquid; a second pressure chamber that extends in the first direction and applies pressure to the liquid; a first nozzle flow path that extends in the first direction and is provided with a first nozzle for ejecting the liquid; a first communication flow path that extends in a second direction intersecting the first direction and communicates with the first pressure chamber and the first nozzle flow path; a second communication flow path that extends in the second direction and communicates with the second pressure chamber and the first nozzle flow path, the width of the first nozzle flow path in the first direction is greater than the width of the first communication flow path in the second direction, and the width of the first nozzle flow path in a third direction intersecting the first direction and the second direction is smaller than the width of the first communication flow path in the third direction.

Description

Technical Field

[0001] The present invention relates to a liquid ejection head and a liquid ejection device. Background Art

[0002] Heretofore, there has been proposed a liquid ejection head that ejects a liquid such as ink from a plurality of nozzles. For example, in Patent Document 1, there is disclosed a liquid ejection head that changes the pressure of a liquid in a pressure chamber by using a piezoelectric element, thereby ejecting the liquid from the nozzle. The liquid ejection head has a plurality of nozzle flow paths provided with nozzles, and these plurality of nozzle flow paths are arranged along a predetermined direction. Further, there are provided a plurality of communication flow paths that communicate with the nozzle flow paths, and these plurality of communication flow paths are also arranged along a predetermined direction.

[0003] Generally, in a liquid ejection head, it is preferable to increase the width in a predetermined direction for both the nozzle flow path and the communication flow path. This is because, by increasing this width, the cross-sectional area of the nozzle flow path and the communication flow path becomes larger, and thus the flow path resistance can be reduced. However, particularly in the case where the nozzle flow paths or the communication flow paths are arranged at a high density in a predetermined direction for high image quality, if the width is increased, the thickness of the partition wall between adjacent nozzle flow paths or between adjacent communication flow paths becomes insufficient. In this case, vibration in one of the nozzle flow paths or the communication flow paths is transmitted to the other nozzle flow path or the communication flow path, and thus there may be a significant occurrence of so-called structural crosstalk that degrades the ejection characteristics of the ejection from the nozzle corresponding to the other nozzle flow path or the communication flow path. When such significant structural crosstalk occurs in both the nozzle flow path and the communication flow path, it may increase the influence on the ejection from the nozzle.

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2013-184372 Summary of the Invention

[0005] In order to solve the above problems, a liquid ejection head according to a preferred aspect of the present invention includes: a first pressure chamber that extends in a first direction and applies pressure to a liquid; a second pressure chamber that extends in the first direction and applies pressure to the liquid; a first nozzle flow path that extends in the first direction and is provided with a first nozzle for ejecting the liquid; a first communication flow path that extends in a second direction intersecting the first direction and communicates with the first pressure chamber and the first nozzle flow path; and a second communication flow path that extends in the second direction and communicates with the second pressure chamber and the first nozzle flow path, wherein the width of the first nozzle flow path in the first direction is greater than the width of the first communication flow path in the second direction, and the width of the first nozzle flow path in a third direction intersecting the first direction and the second direction is smaller than the width of the first communication flow path in the third direction.

[0006] In order to solve the above problems, a liquid ejection head according to another preferred embodiment of the present invention includes: a first pressure chamber that extends in a first direction and applies pressure to a liquid; a second pressure chamber that extends in the first direction and applies pressure to the liquid; a first nozzle flow path that extends in the first direction and is provided with a first nozzle for ejecting the liquid; a first communication flow path that extends in a second direction intersecting the first direction and communicates with the first pressure chamber and the first nozzle flow path; and a second communication flow path that extends in the second direction and communicates with the second pressure chamber and the first nozzle flow path. The width of the first nozzle flow path in the first direction is greater than the width of the first communication flow path in the second direction, and the cross-sectional area of the first nozzle flow path when observed from the first direction is smaller than the cross-sectional area of the first communication flow path when observed from the second direction.

[0007] In order to solve the above problems, a liquid ejection head according to another preferred embodiment of the present invention includes: a first pressure chamber that extends in a first direction and applies pressure to a liquid; a second pressure chamber that extends in the first direction and applies pressure to the liquid; a first nozzle flow path that extends in the first direction and is provided with a first nozzle for ejecting the liquid; a first communication flow path that extends in a second direction intersecting the first direction and communicates with the first pressure chamber and the first nozzle flow path; and a second communication flow path that extends in the second direction and communicates with the second pressure chamber and the first nozzle flow path. The width of the first nozzle flow path in the first direction is smaller than the width of the first communication flow path in the second direction, and the width of the first nozzle flow path in a third direction intersecting the first direction and the second direction is greater than the width of the first communication flow path in the third direction.

[0008] In order to solve the above problems, a liquid ejection head according to another preferred embodiment of the present invention includes: a first pressure chamber that extends in a first direction and applies pressure to a liquid; a second pressure chamber that extends in the first direction and applies pressure to the liquid; a first nozzle flow path that extends in the first direction and is provided with a first nozzle for ejecting the liquid; a first communication flow path that extends in a second direction intersecting the first direction and communicates with the first pressure chamber and the first nozzle flow path; and a second communication flow path that extends in the second direction and communicates with the second pressure chamber and the first nozzle flow path. The width of the first nozzle flow path in the first direction is smaller than the width of the first communication flow path in the second direction, and the cross-sectional area of the first nozzle flow path when observed from the first direction is greater than the cross-sectional area of the first communication flow path when observed from the second direction. Description of the Drawings

[0009] Figure 1 It is a schematic diagram showing a structural example of a part of the liquid ejection device according to the first embodiment.

[0010] Figure 2 It is a schematic diagram showing the flow path structure inside the liquid ejection head.

[0011] Figure 3 It is Figure 2 a cross-sectional view taken along line a-a of

[0012] Figure 4 It is Figure 2 a cross-sectional view taken along line b-b of

[0013] Figure 5 It is Figure 3 and Figure 4 a partial cross-sectional view taken along line c-c of

[0014] Figure 6 It is Figure 3 and Figure 4 a partial cross-sectional view taken along line d-d of

[0015] Figure 7 It is for the second embodiment Figure 2 a cross-sectional view taken along line a-a of

[0016] Figure 8 It is for the second embodiment Figure 2 a cross-sectional view taken along line b-b of

[0017] Figure 9 It is Figure 7 and Figure 8 a partial cross-sectional view taken along line c-c of

[0018] Figure 10 It is Figure 7 and Figure 8 a partial cross-sectional view taken along line d-d of

[0019] Figure 11 It is a schematic diagram showing a structural example of a part of the liquid ejection device according to the third embodiment.

[0020] Figure 12 It is Figure 11 a cross-sectional view taken along line a-a of

[0021] Figure 13 It is Figure 11 a cross-sectional view taken along line b-b of

[0022] Figure 14 It is for the modification example Figure 2 a cross-sectional view taken along line a-a of

[0023] Figure 15 For the deformation example Figure 2 Cross-sectional view taken along line a-a of

[0024] Figure 16 For the deformation example Figure 2 Cross-sectional view taken along line a-a of

[0025] Figure 17 For the deformation example Figure 2 Cross-sectional view taken along line a-a of

[0026] Figure 18 For Figure 17 Cross-sectional view taken along line e-e of

[0027] Figure 19 Schematic diagram showing a structural example of a part of the liquid ejection device related to the deformation example.

[0028] Figure 20 For Figure 19 Cross-sectional view taken along line a-a of

[0029] Figure 21 For Figure 19 Cross-sectional view taken along line b-b of Detailed implementation mode

[0030] A: First implementation mode

[0031] In the following description, assume X-axis, Y-axis, and Z-axis that intersect each other. The X-axis, Y-axis, and Z-axis are common to all the figures exemplified in the subsequent description. As Figure 1 exemplified, when observed from an arbitrary point, one direction along the X-axis is marked as the X1 direction, and the direction opposite to the X1 direction is marked as the X2 direction. The X1 direction corresponds to the "first direction". Similarly, the directions opposite to each other along the Y-axis starting from an arbitrary point are marked as the Y1 direction and the Y2 direction. The Y2 direction corresponds to the "third direction". In addition, the directions opposite to each other along the Z-axis starting from an arbitrary point are marked as the Z1 direction and the Z2 direction. The Z1 direction corresponds to the "second direction". Moreover, the X-Y plane including the X-axis and the Y-axis corresponds to the horizontal plane. The Z-axis is an axis along the vertical direction, and the Z2 direction corresponds to the downward vertical direction.

[0032] Figure 1 Schematic diagram showing a structural example of a part of the liquid ejection device 100 related to the present implementation mode. The liquid ejection device 100 is an inkjet printing device that ejects liquid droplets of ink or the like onto the medium 11. The medium 11 is, for example, printing paper. The medium 11 can also be a printing object made of any material such as a resin film or a cloth.

[0033] In the liquid ejection device 100, a liquid container 12 is provided. The liquid container 12 stores ink. The liquid container 12 may be, for example, a cartridge that can be attached to and detached from the liquid ejection device 100, a bag-shaped ink bag formed of a flexible film, or an ink tank that can be refilled with ink. In addition, the type of ink stored in the liquid container 12 is arbitrary.

[0034] As Figure 1 shown, the liquid ejection device 100 includes a control unit 21, a conveyance mechanism 22, a moving mechanism 23, and a liquid ejection head 24. The control unit 21 includes, for example, a processing circuit such as a CPU (Central Processing Unit) or an FPGA (Field Programmable Gate Array) and a storage circuit such as a semiconductor memory, and controls each element of the liquid ejection device 100 such as the ejection operation of the liquid ejection head 24. The control unit 21 is an example of a "control unit".

[0035] The conveyance mechanism 22 conveys the medium 11 along the Y axis based on the control of the control unit 21. The moving mechanism 23 reciprocates the liquid ejection head 24 along the X axis based on the control of the control unit 21. The moving mechanism 23 includes a substantially box-shaped conveyance body 231 that houses the liquid ejection head 24 and a jointless conveyor belt 232 to which the conveyance body 231 is fixed. In addition, in the present embodiment, a structure in which a plurality of liquid ejection heads 24 are mounted on the conveyance body 231 or a structure in which the liquid container 12 and the liquid ejection head 24 are mounted on the conveyance body 231 together can also be adopted.

[0036] The liquid ejection head 24 ejects the ink supplied from the liquid container 12 from each of a plurality of nozzles onto the medium 11 based on the control of the control unit 21. By ejecting the ink from the liquid ejection head 24 onto the medium 11 in parallel with the conveyance of the medium 11 performed by the conveyance mechanism 22 and the reciprocation of the conveyance body 231, an image is formed on the surface of the medium 11.

[0037] Figure 2 is a schematic diagram showing the flow path structure inside the liquid ejection head 24 when observing the liquid ejection head 24 from the Z axis. As Figure 2As shown, on the surface of the liquid ejection head 24 facing the medium 11, a plurality of nozzles Na and a plurality of nozzles Nb are formed. The plurality of nozzles Na and the plurality of nozzles Nb are arranged along the Y-axis. The plurality of nozzles Na and the plurality of nozzles Nb each eject ink in the Z-axis direction. Therefore, the Z-axis direction corresponds to the direction in which ink is ejected from the plurality of nozzles Na and the plurality of nozzles Nb, respectively. The nozzle Na is an example of the "first nozzle", and the nozzle Nb is an example of the "second nozzle".

[0038] As Figure 2 shown, the plurality of nozzles Na and the plurality of nozzles Nb are respectively located on the same straight line and constitute a nozzle row L. The nozzle row L is a set of the plurality of nozzles Na and the plurality of nozzles Nb that are arranged in a straight line along the Y-axis. In addition, as Figure 2 shown, the nozzles N including the nozzle Na and the nozzle Nb are arranged at a pitch θ. The pitch θ is the distance between the center of the nozzle Na and the center of the nozzle Nb in the Y-axis direction.

[0039] In the following description, a subscript a is added to the symbol of an element associated with the nozzle Na, and a subscript b is added to the symbol of an element associated with the nozzle Nb. In addition, when it is not necessary to particularly distinguish between the nozzle Na and the nozzle Nb, it is only described as "nozzle N".

[0040] As Figure 2 shown, in the liquid ejection head 24, an independent flow path row 25 is provided. The independent flow path row 25 is a set of a plurality of independent flow paths Pa and a plurality of independent flow paths Pb. The plurality of independent flow paths Pa each extend in the X1 direction and correspond to different nozzles Na. The plurality of independent flow paths Pa are respectively connected to the nozzles Na. Similarly, the plurality of independent flow paths Pb each extend in the X1 direction and correspond to different nozzles Nb. The plurality of independent flow paths Pb are respectively connected to the nozzles Nb. In addition, in the following description, when it is not necessary to particularly distinguish between the independent flow path Pa and the independent flow path Pb, it is only described as "independent flow path P".

[0041] In the present embodiment, the independent flow path Pa and the independent flow path Pb adjacent to each other in the Y-axis direction have the same structure. The detailed structure of the independent flow path Pa and the independent flow path Pb will be described later. In addition, in the present application, the meaning of "adjacent" between element A and element B means that when observing element A and element B along a specific direction, at least a part of element A faces at least a part of element B. It is not necessary for all of element A and all of element B to face each other. As long as at least a part of element A faces at least a part of element B, it can be interpreted as "element A is adjacent to element B".

[0042] As Figure 2As shown, the independent flow path Pa has a pressure chamber Ca1 and a pressure chamber Ca2. The pressure chamber Ca1 and the pressure chamber Ca2 in the independent flow path Pa extend in the X1 direction. In the pressure chamber Ca1 and the pressure chamber Ca2, the ink ejected from the nozzle Na communicating with the independent flow path Pa is stored. When the pressure in the pressure chamber Ca1 and the pressure chamber Ca2 changes, the ink is ejected from the nozzle Na. The pressure chamber Ca1 is an example of the "first pressure chamber", and the pressure chamber Ca2 is an example of the "second pressure chamber".

[0043] Similarly, the independent flow path Pb has a pressure chamber Cb1 and a pressure chamber Cb2. The pressure chamber Cb1 and the pressure chamber Cb2 of the independent flow path Pb extend in the X1 direction. In the pressure chamber Cb1 and the pressure chamber Cb2, the ink ejected from the nozzle Nb communicating with the independent flow path Pb is stored. When the pressure in the pressure chamber Cb1 and the pressure chamber Cb2 changes, the ink is ejected from the nozzle Nb. The pressure chamber Cb1 is an example of the "third pressure chamber", and the pressure chamber Cb2 is an example of the "fourth pressure chamber".

[0044] In addition, in the following description, when it is not necessary to particularly distinguish between the pressure chamber Ca1, the pressure chamber Ca2, the pressure chamber Cb1, and the pressure chamber Cb2, it is only described as the "pressure chamber C".

[0045] As Figure 2 shown, in the liquid ejection head 24, a first common liquid chamber R1 and a second common liquid chamber R2 are provided. The first common liquid chamber R1 and the second common liquid chamber R2 extend in the Y-axis direction so as to straddle the entire range in which a plurality of nozzles N are distributed. When viewed from above in the Z-axis direction, the independent flow path row 25 and the plurality of nozzles N are located between the first common liquid chamber R1 and the second common liquid chamber R2. In the following description, the view from above in the Z-axis direction is simply described as the "top view".

[0046] A plurality of independent flow paths P communicate with the first common liquid chamber R1 in common. Specifically, the end portion E1 in the X2 direction of each independent flow path P is connected to the first common liquid chamber R1. Similarly, a plurality of independent flow paths P communicate with the second common liquid chamber R2 in common. Specifically, the end portion E2 in the X1 direction of each independent flow path P is connected to the second common liquid chamber R2. In the liquid ejection head 24, each independent flow path P communicates the first common liquid chamber R1 and the second common liquid chamber R2 with each other. Thus, the ink supplied from the first common liquid chamber R1 to each independent flow path P is ejected from the nozzle N. The ink that is not ejected is discharged to the second common liquid chamber R2.

[0047] As Figure 2As shown, the liquid ejection head 24 has a circulation mechanism 26. The circulation mechanism 26 is a mechanism that returns the ink discharged from each independent flow path P to the first common liquid chamber R1 into the second common liquid chamber R2. The circulation mechanism 26 includes a first supply pump 261, a second supply pump 262, a storage container 263, a circulation flow path 264, and a supply flow path 265.

[0048] The first supply pump 261 is a pump that supplies the ink stored in the liquid container 12 to the storage container 263. The storage container 263 is a sub-tank that temporarily stores the ink supplied from the liquid container 12.

[0049] The circulation flow path 264 is a flow path that connects the second common liquid chamber R2 and the storage container 263, and discharges the ink from the discharge flow path Ra2 and the discharge flow path Rb2, which will be described later, to the storage container 263 via the second common liquid chamber R2. The circulation flow path 264 and the second common liquid chamber R2 are an example of a "common discharge flow path".

[0050] In the storage container 263, in addition to the ink stored in the liquid container 12 supplied from the first supply pump 261, the ink discharged from each independent flow path P into the second common liquid chamber R2 is also supplied via the circulation flow path 264.

[0051] The second supply pump 262 is a pump that sends out the ink stored in the storage container 263. The ink sent out from the second supply pump 262 is supplied to the first common liquid chamber R1 via the supply flow path 265. The supply flow path 265 supplies the liquid to the supply flow path Ra1 and the supply flow path Rb1, which will be described later, in common. The supply flow path 265 and the first common liquid chamber R1 are an example of a "common supply flow path".

[0052] The multiple independent flow paths P of the independent flow path row 25 include multiple independent flow paths Pa and multiple independent flow paths Pb. The multiple independent flow paths Pa are respectively independent flow paths P that communicate with one nozzle Na of the nozzle row L. Similarly, the multiple independent flow paths Pb are respectively independent flow paths P that communicate with one nozzle Nb of the nozzle row L. The independent flow paths Pa and the independent flow paths Pb are alternately arranged along the Y-axis direction. Thus, the independent flow paths Pa and the independent flow paths Pb are adjacent to each other in the Y-axis direction.

[0053] As Figure 2 shown, the independent flow path Pa has a nozzle flow path Nfa. The nozzle flow path Nfa extends in the X1 direction, and as shown in this figure, when viewed in the Z2 direction, it is located between the pressure chamber Ca1 and the pressure chamber Ca2. The nozzle flow path Nfa communicates with the pressure chamber Ca1 and the pressure chamber Ca2, and is provided with a nozzle Na that ejects the ink supplied from the pressure chamber Ca1. The nozzle flow path Nfa is an example of a "first nozzle flow path".

[0054] As Figure 2 shown, the independent flow path Pb has a nozzle flow path Nfb. The nozzle flow path Nfb extends in the X1 direction, and as shown in this figure, when viewed in the Z2 direction, it is located between the pressure chamber Cb1 and the pressure chamber Cb2. The nozzle flow path Nfb communicates with the pressure chamber Cb1 and the pressure chamber Cb2, and is provided with a nozzle Nb for ejecting the ink supplied from the pressure chamber Cb1. The nozzle flow path Nfb is an example of a "second nozzle flow path".

[0055] The nozzle flow path Nfa and the nozzle flow path Nfb are alternately arranged along the Y-axis direction. The nozzle flow path Nfa and the nozzle flow path Nfb are adjacent to each other with a predetermined interval in the Y-axis direction.

[0056] In the liquid ejection head 24 of the present embodiment, as Figure 2 shown, a plurality of pressure chambers Ca1 corresponding to different nozzles Na of the nozzle row L, and a plurality of pressure chambers Cb1 corresponding to different nozzles Nb of the nozzle row L are arranged in a straight line along the Y-axis direction. Similarly, a plurality of pressure chambers Ca2 corresponding to different nozzles Na of the nozzle row L, and a plurality of pressure chambers Cb2 corresponding to different nozzles Nb of the nozzle row L are arranged in a straight line along the Y-axis direction. The arrangement composed of the plurality of pressure chambers Ca1 and the plurality of pressure chambers Cb1, and the arrangement composed of the plurality of pressure chambers Ca2 and the plurality of pressure chambers Cb2 are arranged side by side with a predetermined interval in the X-axis direction. Here, although the positions of the respective pressure chambers Ca1 in the Y-axis direction, and the positions of the respective pressure chambers Ca2 in the Y-axis direction are the same, they may also be different. Similarly, here, although the positions of the respective pressure chambers Cb1 in the Y-axis direction, and the positions of the respective pressure chambers Cb2 in the Y-axis direction are also the same, they may also be different.

[0057] Next, the detailed structure of the liquid ejection head 24 will be described. Figure 3 is Figure 2 a cross-sectional view taken along the line a-a of Figure 4 is Figure 2 a cross-sectional view taken along the line b-b of Figure 3 shows the cross-section through the independent flow path Pa, and Figure 4 shows the cross-section through the independent flow path Pb.

[0058] As Figure 3 well as Figure 4 shown, the liquid ejection head 24 has a flow path structure body 30, a plurality of piezoelectric elements 41, a housing portion 42, a protection substrate 43, and a wiring substrate 44. The flow path structure body 30 is a structure body in which a flow path having a first common liquid chamber R1, a second common liquid chamber R2, a plurality of independent flow paths P, and a plurality of nozzles N is formed.

[0059] The flow channel structure 30 is a structure formed by laminating a nozzle substrate 31, a connection plate 33, a pressure chamber substrate 34, and a vibration plate 35 in the Z1 direction in sequence. These elements constituting the flow channel structure 30 are manufactured by processing a single crystal substrate using, for example, general processing methods for manufacturing semiconductors.

[0060] On the nozzle substrate 31, a plurality of nozzles N are formed. Each of the plurality of nozzles N is a cylindrical through-hole through which ink passes. As Figure 3 and Figure 4 shown, the nozzle substrate 31 is a plate-like member having a surface Fa1 facing the Z2 direction and a surface Fa2 facing the Z1 direction. The connection plate 33 is a plate-like member having a surface Fc1 facing the Z2 direction and a surface Fc2 facing the Z1 direction.

[0061] Each element constituting the flow channel structure 30 is formed in a long rectangular shape in the Y-axis direction and is joined to each other by, for example, an adhesive. For example, the surface Fa2 of the nozzle substrate 31 is joined to the surface Fc1 of the connection plate 33, the surface Fc2 of the connection plate 33 is joined to the surface Fd1 of the pressure chamber substrate 34, and the surface Fd2 of the pressure chamber substrate 34 is joined to the surface Fe1 of the vibration plate 35.

[0062] In the connection plate 33, a space O12 and a space O22 are formed. The space O12 and the space O22 are each an opening elongated in the Y-axis direction. On the surface Fc1 of the connection plate 33, a vibration absorber 361 for closing the space O12 and a vibration absorber 362 for closing the space O22 are provided. The vibration absorber 361 and the vibration absorber 362 are layered members formed of an elastic material. The connection plate 33 is an example of a "first connection plate".

[0063] The housing portion 42 is a housing for storing ink. The housing portion 42 is joined to the surface Fc2 of the connection plate 33. In the housing portion 42, a space O13 communicating with the space O12 and a space O23 communicating with the space O22 are formed. The space O13 and the space O23 are each a space elongated in the Y-axis direction. The space O12 and the space O13 communicate with each other to constitute a first common liquid chamber R1. Similarly, the space O22 and the space O23 communicate with each other to constitute a second common liquid chamber R2. The vibration absorber 361 constitutes the wall surface of the first common liquid chamber R1 and absorbs the pressure fluctuations of the ink in the first common liquid chamber R1. The vibration absorber 362 constitutes the wall surface of the second common liquid chamber R2 and absorbs the pressure fluctuations of the ink in the second common liquid chamber R2.

[0064] In the housing portion 42, a supply port 421 and a discharge port 422 are formed. The supply port 421 is a pipe communicating with the first common liquid chamber R1 and is connected to the supply flow path 265 of the circulation mechanism 26. The ink sent from the second supply pump 262 to the supply flow path 265 is supplied to the first common liquid chamber R1 via the supply port 421. On the other hand, the discharge port 422 is a pipe communicating with the second common liquid chamber R2 and is connected to the circulation flow path 264 of the circulation mechanism 26. The ink in the second common liquid chamber R2 is supplied to the circulation flow path 264 via the discharge port 422.

[0065] In the pressure chamber substrate 34, a pressure chamber Ca1, a pressure chamber Ca2, a pressure chamber Cb1, and a pressure chamber Cb2 are provided. Each pressure chamber C is the space between the surface Fc2 of the communication plate 33 and the diaphragm 35. Each pressure chamber C is formed in a long strip shape along the X-axis in a plan view and extends in the X1 direction.

[0066] The diaphragm 35 is a plate-like member that can vibrate elastically. The diaphragm 35 is composed of, for example, a first layer of silicon dioxide (SiO2) and a second layer of zirconium oxide (ZrO2) laminated. Alternatively, the diaphragm 35 and the pressure chamber substrate 34 can be integrally formed by selectively removing a part in the thickness direction from a region corresponding to the pressure chamber C in a plate-like member having a predetermined thickness. In addition, the diaphragm 35 can be formed in a single layer.

[0067] On the surface Fe2 of the diaphragm 35, a plurality of piezoelectric elements 41 corresponding to different pressure chambers C are formed. The piezoelectric elements 41 corresponding to the respective pressure chambers C overlap the pressure chambers C in a plan view. Specifically, each piezoelectric element 41 is composed of a first electrode and a second electrode facing each other and a piezoelectric layer formed between the two electrodes laminated. Each piezoelectric element 41 is an energy generating element that generates energy and changes the pressure of the ink in the pressure chamber C by this energy, so that the ink in the pressure chamber C is ejected from the nozzle N. The piezoelectric element 41 deforms itself by receiving a drive signal, thereby vibrating the diaphragm 35. When the diaphragm 35 vibrates, the pressure chamber C expands and contracts. By the expansion and contraction of the pressure chamber C, pressure is applied to the ink from the pressure chamber C. Thereby, the ink is ejected from the nozzle N.

[0068] The protective substrate 43 is a plate-like member provided on the surface Fe2 of the diaphragm 35, which protects the plurality of piezoelectric elements 41 and strengthens the mechanical strength of the diaphragm 35. A plurality of piezoelectric elements 41 are accommodated between the protective substrate 43 and the diaphragm 35. In addition, a wiring substrate 44 is mounted on the surface Fe2 of the diaphragm 35. The wiring substrate 44 is a mounting member for electrically connecting the control unit 21 and the liquid ejection head 24. For example, it is preferable to use a flexible wiring substrate 44 such as an FPC (Flexible Printed Circuit) or an FFC (Flexible Flat Cable). A drive circuit 45 for supplying drive signals to the respective piezoelectric elements 41 is mounted on the wiring substrate 44.

[0069] Next, the structure of the independent flow path P will be described. In the following description, since the independent flow paths Pa and Pb have the same structure as described above, when describing the structure of the independent flow path P, the structure of the independent flow path Pa will be mainly used as a representative for description among the independent flow paths Pa and Pb. In addition, regarding the structure of the independent flow path Pb, by replacing the subscript a of the symbol of each element constituting the independent flow path Pa with the subscript b, the description of each element constituting the independent flow path Pb also holds true. Here, the supply flow path Rb1 is an example of the "second independent supply flow path", and the discharge flow path Rb2 is an example of the "second independent discharge flow path". In addition, the nozzle flow path Nfb is an example of the "second nozzle flow path".

[0070] As Figure 3 shown, the independent flow path Pa has a supply flow path Ra1, a pressure chamber Ca1, a first communication flow path Na1, a nozzle flow path Nfa, a second communication flow path Na2, a pressure chamber Ca2, and a discharge flow path Ra2. The independent flow path Pa is a flow path integrally formed by these elements and is a flow path in which the above elements are connected in the above order.

[0071] The supply flow path Ra1 is a space formed in the communication plate 33. Specifically, as Figure 3 shown, the supply flow path Ra1 extends from the space O12 constituting the first common liquid chamber R1 along the Z axis to the surface Fc2 of the communication plate 33. The end of the supply flow path Ra1 connected to the space O12 is the end E1 of the independent flow path Pa. The supply flow path Ra1 is a flow path that communicates with the pressure chamber Ca1 and guides the ink supplied from the first common liquid chamber R1 to the pressure chamber Ca1. The supply flow path Ra1 is an example of the "first independent supply flow path".

[0072] As Figure 3As shown, the first communication flow path Na1 is a space penetrating the connection plate 33. The first communication flow path Na1 is a long strip-shaped flow path along the Z-axis. The first communication flow path Na1 extends in the Z1 direction and communicates with the pressure chamber Ca1 and the nozzle flow path Nfa. The first communication flow path Na1 is a flow path that guides the ink extruded from the pressure chamber Ca1 to the nozzle flow path Nfa.

[0073] The nozzle flow path Nfa is a flow path provided on the connection plate 33 and extending in the X-axis direction. As Figure 2 shown, when viewed in the Z-axis direction, the nozzle flow path Nfa is located between the first communication flow path Na1 and the second communication flow path Na2. The nozzle flow path Nfa communicates with the first communication flow path Na1 and the second communication flow path Na2, and a nozzle Na is provided. The nozzle flow path Nfa is a flow path that guides the ink supplied from the first communication flow path Na1 and not ejected from the nozzle Na to the second communication flow path Na2.

[0074] As Figure 3 shown, the width Wa in the X1 direction of the nozzle flow path Nfa is longer than the width ha in the Z1 direction of the first communication flow path Na1 and the second communication flow path Na2. That is, the flow path length of the nozzle flow path Nfa is longer than the flow path lengths of the first communication flow path Na1 and the second communication flow path Na2. In the present embodiment, the ratio of the width Wa to the width ha, that is, Wa / ha, is preferably 1.5 or more and 4.0 or less.

[0075] As Figure 3 shown, the second communication flow path Na2 is a space penetrating the connection plate 33. The second communication flow path Na2 is a long strip-shaped flow path along the Z-axis. The second communication flow path Na2 extends in the Z1 direction and communicates with the pressure chamber Ca2 and the nozzle flow path Nfa. The second communication flow path Na2 is a flow path that guides the ink supplied by the nozzle flow path Nfa to the pressure chamber Ca2.

[0076] The discharge flow path Ra2 is a space formed in the connection plate 33. Specifically, the discharge flow path Ra2 extends along the Z-axis from the space O22 constituting the second common liquid chamber R2 to the surface Fc2 of the connection plate 33. The end of the discharge flow path Ra2 connected to the space O22 is the end E2 of the independent flow path Pa. The discharge flow path Ra2 is a flow path that communicates with the pressure chamber Ca2 and guides the ink extruded from the pressure chamber Ca2 to the second common liquid chamber R2. The discharge flow path Ra2 is an example of the "first independent discharge flow path".

[0077] In the above structure, during the operation of the liquid ejection head 24 in the liquid ejection device 100, while circulating the ink, the ink is ejected. Specifically, the ink from the liquid container 12 is supplied to the first common liquid chamber R1 via the supply flow path 265. After that, a drive signal for driving the piezoelectric elements by a drive unit including the drive circuit 45 etc. is output to the piezoelectric element 41 on the pressure chamber Ca1 side and the piezoelectric element 41 on the pressure chamber Ca2 side, so that the piezoelectric element 41 on the pressure chamber Ca1 side and the piezoelectric element 41 on the pressure chamber Ca2 side are driven simultaneously. Thereby, the ink supplied to the first common liquid chamber R1 is ejected from the nozzle Na. In addition, the ink in the nozzle flow path Nfa that is not ejected from the nozzle Na is supplied to the second common liquid chamber R2 via the discharge flow path Ra2. The piezoelectric element 41 on the pressure chamber Ca1 side is an example of the "first energy generating element", and the piezoelectric element 41 on the pressure chamber Ca2 side is an example of the "second energy generating element". In addition, the actions of circulating the ink related to the independent flow path Pa and the actions of circulating the ink related to the independent flow path Pb described above are the same.

[0078] The liquid ejection head 24 of the present embodiment can suppress the thickening of the ink near the nozzle Na and the nozzle Nb and the precipitation of components by circulating the ink during ink ejection, thereby preventing the deterioration of the ink ejection characteristics. Thereby, the ink ejection characteristics can be basically kept fixed, and the deviation of the ejection characteristics can be suppressed, thus improving the ink ejection quality. In addition, the "ejection characteristics" described above are, for example, the ink ejection amount or the ejection speed. This is the same in the following description.

[0079] Figure 5 is Figure 3 and Figure 4 a partial cross-sectional view taken along the c-c line of Figure 6 is Figure 3 and Figure 4 a partial cross-sectional view taken along the d-d line of. In Figure 6 the illustration of the nozzle substrate 31 is omitted.

[0080] The width Da of the nozzle flow path Nfa in the Y2 direction is smaller than the width Da1 of the first communication flow path Na1 in the Y2 direction and smaller than the width Da2 of the second communication flow path Na2 in the Y2 direction. Similarly, the width Db of the nozzle flow path Nfb in the Y2 direction is smaller than the width Db1 of the third communication flow path Nb1 in the Y2 direction and smaller than the width Db2 of the fourth communication flow path Nb2 in the Y2 direction.

[0081] In addition, as Figure 5As shown, the distance between the nozzle flow channels Nfa and Nfb in the Y-axis direction, that is, the thickness D1 of the partition wall disposed between the nozzle flow channels Nfa and Nfb in the Y-axis direction and the thickness D2 of the partition wall disposed between the first communication flow channel Na1 and the third communication flow channel Nb1 in the Y-axis direction, and the thickness D3 of the partition wall disposed between the second communication flow channel Na2 and the fourth communication flow channel Nb2 in the Y-axis direction are relatively thick.

[0082] Moreover, in the present embodiment, when observed in the X-axis direction, the cross-sectional area of the nozzle flow channel Nfa is smaller than that of the first communication flow channel Na1 and the second communication flow channel Na2 when observed in the Z-axis direction as indicated by the vertical lines of Figure 5 . Similarly, when observed in the X-axis direction, the cross-sectional area of the nozzle flow channel Nfb is smaller than that of the third communication flow channel Nb1 and the fourth communication flow channel Nb2 when observed in the Z-axis direction as indicated by the vertical lines of Figure 5 .

[0083] The reason for adopting the above structure will be described. In the following description, for simplicity, only the nozzle flow channels Nfa and Nfb, and the first communication flow channel Na1 and the third communication flow channel Nb1 will be described. Although the second communication flow channel Na2 and the fourth communication flow channel Nb2 are not particularly described, the relationship between the nozzle flow channels Nfa and Nfb is the same as that between the first communication flow channel Na1 and the third communication flow channel Nb1.

[0084] As described above, in the first embodiment, the widths Wa and Wb of the nozzle flow channels Nfa and Nfb in the X1 direction are greater than the widths ha and hb of the first communication flow channel Na1 and the third communication flow channel Nb1 in the Z1 direction. Here, between adjacent nozzle flow channels and between adjacent communication flow channels, vibrations caused by changes in the internal pressure of one flow channel will propagate to the other flow channel, which may cause a phenomenon of deterioration in the ejection characteristics of the nozzles connected to the flow channel (hereinafter referred to as "structural crosstalk"). For this structural crosstalk, since the longer the adjacent widths of those flow channels, the longer the vibration transfer time, the greater the impact. That is, assuming that the widths of each flow channel in the Y-axis direction are the same, compared with between the first communication flow channel Na1 and the third communication flow channel Nb1, structural crosstalk may occur significantly between the nozzle flow channels Nfa and Nfb.

[0085] In view of the above, in the first embodiment, as Figure 5 and Figure 6As shown, the widths Da and Db in the Y-axis direction of the nozzle flow channels Nfa and Nfb are set to relatively small values. Thereby, the thickness D1 of the partition wall between the nozzle flow channels Nfa and Nfb can be made relatively large, so that even if vibration occurs in one of the nozzle flow channels, it is difficult for the vibration to propagate to the other nozzle flow channel. Therefore, the structural crosstalk between the nozzle flow channels Nfa and Nfb can be reduced.

[0086] On the other hand, if the first communication flow channels Na1 and the third communication flow channels Nb1 also reduce the widths in the Y-axis direction in the same manner as the nozzle flow channels Nfa and Nfb, the influence of structural crosstalk can be further reduced. However, since the widths ha and hb in the Z-axis direction of the first communication flow channels Na1 and the third communication flow channels Nb1 are small as described above, the structural crosstalk is not obvious originally. Instead, if the widths in the Y-axis direction of the first communication flow channels Na1 and the third communication flow channels Nb1 are reduced, both the flow channel cross-sectional area of the first communication flow channel Na1 and the flow channel cross-sectional area of the nozzle flow channel Nfa will become smaller, thereby increasing the flow channel resistance of the entire flow channel corresponding to the nozzle Na. The same applies to the nozzle Nb. Therefore, for the first communication flow channels Na1 and the third communication flow channels Nb1, by making the widths Da1 and Db1 in the Y-axis direction larger, an increase in flow channel resistance can be suppressed.

[0087] As described above, according to the first embodiment, it is possible to reduce the structural crosstalk in the nozzle flow channel while suppressing an increase in the flow channel resistance in each communication flow channel.

[0088] B: Second Embodiment

[0089] Figure 7 is a cross-sectional view taken along line a-a of Figure 2 for the second embodiment, Figure 8 is a cross-sectional view taken along line b-b of Figure 2 for the second embodiment. Hereinafter, for the same structures as those in the first embodiment, the same reference numerals are used, and their detailed descriptions are omitted or simplified.

[0090] In the liquid ejection head 24 of the second embodiment, the flow channel lengths and flow channel widths of the nozzle flow channels Nfa and Nfb are different from those in the first embodiment. Specifically, the width Wa in the X1 direction of the nozzle flow channel Nfa is smaller than the width ha in the Z1 direction of the first communication flow channel Na1 and the second communication flow channel Na2. That is, the flow channel length of the nozzle flow channel Nfa is shorter than the flow channel lengths of the first communication flow channel Na1 and the second communication flow channel Na2.

[0091] Figure 9 is Figure 7 andFigure 8 Partial cross-sectional view of the c-c line Figure 10 is Figure 7 and Figure 8 partial cross-sectional view of the d-d line. In Figure 10 the illustration of the nozzle substrate 31 is omitted

[0092] The width Da of the nozzle flow path Nfa in the Y2 direction is greater than the width Da1 of the first communication flow path Na1 in the Y2 direction and greater than the width Da2 of the second communication flow path Na2 in the Y2 direction. Similarly, the width Db of the nozzle flow path Nfb in the Y2 direction is greater than the width Db1 of the third communication flow path Nb1 in the Y2 direction and greater than the width Db2 of the fourth communication flow path Nb2 in the Y2 direction

[0093] In addition, as Figure 9 shown, the distance between the nozzle flow path Nfa and the nozzle flow path Nfb in the Y-axis direction, that is, the thickness D1 of the partition wall provided between the nozzle flow path Nfa and the nozzle flow path Nfb in the Y-axis direction, is smaller compared to the thickness D2 of the partition wall provided between the first communication flow path Na1 and the third communication flow path Nb1 in the Y-axis direction and the thickness D3 of the partition wall provided between the second communication flow path Na2 and the fourth communication flow path Nb2 in the Y-axis direction

[0094] Moreover, in the second embodiment, the cross-sectional area of the nozzle flow path Nfa when viewed in the X-axis direction is greater than the cross-sectional areas of the first communication flow path Na1 and the second communication flow path Na2 when viewed in the Z-axis direction shown by the vertical lines of Figure 9 . Similarly, the cross-sectional area of the nozzle flow path Nfb when viewed in the X-axis direction is greater than the cross-sectional areas of the third communication flow path Nb1 and the fourth communication flow path Nb2 when viewed in the Z-axis direction shown by the vertical lines of Figure 9

[0095] In the second embodiment, the widths Wa and Wb of the nozzle flow path Nfa and the nozzle flow path Nfb in the X1 direction are smaller than the widths ha and hb of the first communication flow path Na1 and the third communication flow path Nb1 in the Z1 direction. Therefore, assuming that the widths of each flow path in the Y-axis direction are the same, structural crosstalk may occur significantly more between the first communication flow path Na1 and the third communication flow path Nb1 compared to between the nozzle flow path Nfa and the nozzle flow path Nfb

[0096] In view of the above, in the second embodiment, as Figure 9 and Figure 10 ​As shown below, the widths Da1 in the Y-axis direction of the first communication flow path Na1 and the third communication flow path Nb1 are set to relatively small values. Accordingly, the thickness D2 of the partition wall between the first communication flow path Na1 and the third communication flow path Nb1 can be made relatively large, so that even if vibration occurs in one of the communication flow paths, it is difficult for the vibration to propagate to the other communication flow path. The same applies to between the second communication flow path Na2 and the fourth communication flow path Nb2. Therefore, structural crosstalk between the first communication flow path Na1 and the third communication flow path Nb1 and between the second communication flow path Na2 and the fourth communication flow path Nb2 is reduced.

[0097] On the other hand, in the second embodiment, for the nozzle flow paths Nfa and Nfb where structural crosstalk is not likely to occur, the widths Da and Db in the Y-axis direction can be made relatively large to suppress an increase in flow path resistance.

[0098] As described above, according to the second embodiment, it is possible to reduce structural crosstalk in the communication flow paths while suppressing an increase in the flow path resistance of the nozzle flow paths.

[0099] C: Third Embodiment

[0100] Figure 11 FIG. is a schematic diagram showing a flow path structure in the liquid ejection head 24 when observing the liquid ejection head 24 according to the third embodiment in the Z-axis direction. As Figure 11 Illustrated, a plurality of nozzles N (Na, Nb) are formed on the surface of the liquid ejection head 24 facing the medium 11. The plurality of nozzles N are arranged along the Y-axis. Ink is ejected from each of the plurality of nozzles N in the Z-axis direction. That is, the Z-axis corresponds to the direction in which ink is ejected from each nozzle N.

[0101] The plurality of nozzles N in the third embodiment are divided into a first nozzle row La and a second nozzle row Lb. The first nozzle row La is a set of a plurality of nozzles Na arranged linearly along the Y-axis. Similarly, the second nozzle row Lb is a set of a plurality of nozzles Nb arranged linearly along the Y-axis. The first nozzle row La and the second nozzle row Lb are arranged side by side at a predetermined interval in the X-axis direction. In addition, the positions of the respective nozzles Na in the Y-axis direction are different from the positions of the respective nozzles Nb in the Y-axis direction. As Figure 11 Illustrated, the plurality of nozzles N including the nozzle Na and the nozzle Nb are arranged at a pitch (period) θ. The pitch θ is the distance between the centers of the nozzle Na and the nozzle Nb in the Y-axis direction.

[0102] As Figure 11As illustrated, in the liquid ejection head 24, an independent flow path row 25 is provided. The independent flow path row 25 is a collection of a plurality of independent flow paths P (Pa, Pb) corresponding to different nozzles N. Each of the plurality of independent flow paths P is a flow path communicating with the nozzle N corresponding to the independent flow path P. Each independent flow path P extends along the X axis. The independent flow path row 25 is composed of a plurality of independent flow paths P arranged side by side along the Y axis. In addition, although in Figure 11 each independent flow path P is simply illustrated in a simple straight line manner, the actual shape of each independent flow path P will be described later.

[0103] Each independent flow path P includes a pressure chamber C (Ca, Cb). The pressure chamber C in each independent flow path P is a space for storing the ink ejected from the nozzle N communicating with the independent flow path P. That is, the ink is ejected from the nozzle N by changing the pressure of the ink in the pressure chamber C.

[0104] As Figure 11 illustrated, in the liquid ejection head 24, a first common liquid chamber R1 and a second common liquid chamber R2 are provided. The first common liquid chamber R1 and the second common liquid chamber R2 each extend in the Y-axis direction over the entire area of the range in which a plurality of nozzles N are distributed. When viewed from above, the independent flow path row 25 and the plurality of nozzles N are located between the first common liquid chamber R1 and the second common liquid chamber R2.

[0105] The plurality of independent flow paths P communicate with the first common liquid chamber R1 in common. Specifically, the end E1 in the X2 direction of each independent flow path P is connected to the first common liquid chamber R1. In addition, the plurality of independent flow paths P communicate with the second common liquid chamber R2 in common. Specifically, the end E2 in the X1 direction of each independent flow path P is connected to the second common liquid chamber R2. As understood from the above description, each independent flow path P connects the first common liquid chamber R1 and the second common liquid chamber R2 to each other. The ink supplied from the first common liquid chamber R1 to each independent flow path P is ejected from the nozzle N corresponding to the independent flow path P. In addition, the portion of the ink supplied from the first common liquid chamber R1 to each independent flow path P that is not ejected from the nozzle N is discharged into the second common liquid chamber R2.

[0106] As Figure 11 illustrated, the liquid ejection device 100 of the third embodiment includes a circulation mechanism 26. The circulation mechanism 26 is a mechanism that returns the ink discharged from each independent flow path P to the first common liquid chamber R1. Specifically, the circulation mechanism 26 includes a first supply pump 261, a second supply pump 262, a storage container 263, a circulation flow path 264, and a supply flow path 265.

[0107] The first supply pump 261 is a pump that supplies the ink stored in the liquid container 12 to the storage container 263. The storage container 263 is a sub-tank that temporarily stores the ink supplied from the liquid container 12. The circulation flow path 264 is a flow path that connects the second common liquid chamber R2 and the storage container 263. In the storage container 263, in addition to the ink stored in the liquid container 12 being supplied by the first supply pump 261, the ink discharged from each independent flow path P to the second common liquid chamber R2 is also supplied via the circulation flow path 264. The second supply pump 262 is a pump that sends out the ink stored in the storage container 263. The ink sent out by the second supply pump 262 is supplied to the first common liquid chamber R1 via the supply flow path 265.

[0108] The multiple independent flow paths P of the independent flow path row 25 include multiple independent flow paths Pa and multiple independent flow paths Pb. The multiple independent flow paths Pa are respectively independent flow paths P that communicate with one nozzle Na of the first nozzle row La. The multiple independent flow paths Pb are respectively independent flow paths P that communicate with one nozzle Nb of the second nozzle row Lb. The independent flow paths Pa and the independent flow paths Pb are alternately arranged along the Y axis. That is, the independent flow paths Pa and the independent flow paths Pb are adjacent in the Y-axis direction.

[0109] The independent flow path Pa includes a first part Pa1 and a second part Pa2. The first part Pa1 of each independent flow path Pa is the flow path between the end E1 connected to the first common liquid chamber R1 in this independent flow path Pa and the nozzle Na communicating with this independent flow path Pa. The first part Pa1 includes a pressure chamber Ca. On the other hand, the second part Pa2 of each independent flow path Pa is the flow path between the nozzle Na communicating with this independent flow path Pa and the end E2 connected to the second common liquid chamber R2 in this independent flow path Pa.

[0110] The independent flow path Pb includes a third part Pb1 and a fourth part Pb2. The third part Pb1 of each independent flow path Pb is the flow path between the end E1 connected to the first common liquid chamber R1 in this independent flow path Pb and the nozzle Nb communicating with this independent flow path Pb. On the other hand, the fourth part Pb2 of each independent flow path Pb is the flow path between the nozzle Nb communicating with this independent flow path Pb and the end E2 connected to the second common liquid chamber R2 in this independent flow path Pb. The fourth part Pb2 includes a pressure chamber Cb.

[0111] As understood from the above description, a plurality of pressure chambers Ca corresponding to different nozzles Na of the first nozzle row La are linearly arranged along the Y axis. Similarly, a plurality of pressure chambers Cb corresponding to different nozzles Nb of the second nozzle row Lb are linearly arranged along the Y axis. The arrangement of the plurality of pressure chambers Ca and the arrangement of the plurality of pressure chambers Cb are arranged side by side at a predetermined interval in the X axis direction. The positions of the respective pressure chambers Ca in the Y axis direction and the positions of the respective pressure chambers Cb in the Y axis direction are different.

[0112] In addition, as Figure 11 understood, the first portions Pa1 of the respective independent flow paths Pa and the third portions Pb1 of the respective independent flow paths Pb are arranged in the Y axis direction, and the second portions Pa2 of the respective independent flow paths Pa and the fourth portions Pb2 of the respective independent flow paths Pb are arranged in the Y axis direction.

[0113] The specific structure of the liquid ejection head 24 will be described in detail below. Figure 12 For Figure 11 a cross-sectional view taken along line a-a of Figure 13 and Figure 11 is a cross-sectional view taken along line b-b of Figure 12 The cross-section through the independent flow path Pa is illustrated in Figure 13 and the cross-section through the independent flow path Pb is illustrated in

[0114] As Figure 12 and Figure 13 exemplified, the liquid ejection head 24 includes a flow path structure body 30, a plurality of piezoelectric elements 41, a housing portion 42, a protective substrate 43, and a wiring substrate 44. The flow path structure body 30 is a structure body in which a flow path including a first common liquid chamber R1, a second common liquid chamber R2, a plurality of independent flow paths P, and a plurality of nozzles N is formed inside.

[0115] The flow path structure body 30 is a structure body in which a nozzle substrate 31, a communication plate 33, a pressure chamber substrate 34, and a diaphragm 35 are laminated in this order in the Z1 direction. Each component constituting the flow path structure body 30 is manufactured, for example, by processing a single crystal substrate using semiconductor manufacturing technology.

[0116] A plurality of nozzles N are formed on the nozzle substrate 31. The plurality of nozzles N are each circular through holes through which ink passes. The nozzle substrate 31 of the first embodiment is a plate-like member including a surface Fa1 in the Z2 direction and a surface Fa2 in the Z1 direction.

[0117] Figure 12 and Figure 13The connecting plate 33 is a plate-like member including a surface Fc1 in the Z2 direction and a surface Fc2 in the Z1 direction.

[0118] The pressure chamber substrate 34 is a plate-like member including a surface Fd1 in the Z2 direction and a surface Fd2 in the Z1 direction. The diaphragm 35 is a plate-like member including a surface Fe1 in the Z2 direction and a surface Fe2 in the Z1 direction.

[0119] Each component constituting the flow path structure 30 is formed into a long rectangular shape in the Y-axis direction and is joined to each other by, for example, an adhesive. For example, the surface Fa2 of the nozzle substrate 31 is joined to the surface Fc1 of the connecting plate 33. In addition, the surface Fc2 of the connecting plate 33 is joined to the surface Fd1 of the pressure chamber substrate 34, and the surface Fd2 of the pressure chamber substrate 34 is joined to the surface Fe1 of the diaphragm 35.

[0120] In the connecting plate 33, a space O12 and a space O22 are formed. The space O12 and the space O22 are each an opening that is long in the Y-axis direction. On the surface Fc1 of the connecting plate 33, a vibration absorber 361 that closes the space O12 and a vibration absorber 362 that closes the space O22 are provided. The vibration absorber 361 and the vibration absorber 362 are layered members formed of an elastic material.

[0121] The housing portion 42 is a housing for storing ink. The housing portion 42 is joined to the surface Fc2 of the connecting plate 33. In the housing portion 42, a space O13 that communicates with the space O12 and a space O23 that communicates with the space O22 are formed. The space O13 and the space O23 are each a space that is long in the Y-axis direction. The space O12 and the space O13 communicate with each other to constitute a first common liquid chamber R1. Similarly, the space O22 and the space O23 communicate with each other to constitute a second common liquid chamber R2. The vibration absorber 361 constitutes the wall surface of the first common liquid chamber R1 and absorbs pressure fluctuations of the ink in the first common liquid chamber R1. The vibration absorber 362 constitutes the wall surface of the second common liquid chamber R2 and absorbs pressure fluctuations of the ink in the second common liquid chamber R2.

[0122] In the housing portion 42, a supply port 421 and a discharge port 422 are formed. The supply port 421 is a pipe that communicates with the first common liquid chamber R1 and is connected to the supply flow path 265 of the circulation mechanism 26. The ink sent to the supply flow path 265 by the second supply pump 262 is supplied to the first common liquid chamber R1 via the supply port 421. On the other hand, the discharge port 422 is a pipe that communicates with the second common liquid chamber R2 and is connected to the circulation flow path 264 of the circulation mechanism 26. The ink in the second common liquid chamber R2 is supplied to the circulation flow path 264 via the discharge port 422.

[0123] In the pressure chamber substrate 34, a plurality of pressure chambers C (Ca, Cb) are formed. Each pressure chamber C is a gap that communicates the surface Fc2 of the communication plate 33 and the surface Fe1 of the diaphragm 35. When viewed from above, each pressure chamber C is formed in a long strip shape along the X axis.

[0124] The diaphragm 35 is a plate-like member that can vibrate elastically. The diaphragm 35 is constituted, for example, by laminating a first layer of silica (SiO2) and a second layer of zirconia (ZrO2). Alternatively, the diaphragm 35 and the pressure chamber substrate 34 can be integrally formed by selectively removing a part in the thickness direction of a plate-like member having a predetermined thickness in a region corresponding to the pressure chamber C. In addition, the diaphragm 35 can be formed in a single layer.

[0125] On the surface Fe2 of the diaphragm 35, a plurality of piezoelectric elements 41 corresponding to different pressure chambers C are provided. The piezoelectric element 41 corresponding to each pressure chamber C overlaps with the pressure chamber C when viewed from above. Specifically, each piezoelectric element 41 is constituted by laminating a first electrode and a second electrode facing each other and a piezoelectric body layer formed between the two electrodes. Each piezoelectric element 41 is an energy generating element that causes the ink in the pressure chamber C to be ejected from the nozzle N by changing the pressure of the ink in the pressure chamber C. That is, by deforming the piezoelectric element 41 by supplying a drive signal, the diaphragm 35 vibrates, and by using the vibration of the diaphragm 35, the pressure chamber C expands and contracts, so that the ink is ejected from the nozzle N.

[0126] The protection substrate 43 is a plate-like member provided on the surface Fe2 of the diaphragm 35, protects the plurality of piezoelectric elements 41, and strengthens the mechanical strength of the diaphragm 35. A plurality of piezoelectric elements 41 are housed between the protection substrate 43 and the diaphragm 35. In addition, a wiring substrate 44 is mounted on the surface Fe2 of the diaphragm 35. The wiring substrate 44 is a mounting member for electrically connecting the control unit 21 and the liquid ejection head 24. For example, it is preferable to use a flexible wiring substrate 44 such as an FPC (Flexible Printed Circuit) or an FFC (Flexible Flat Cable). A drive circuit 45 for supplying a drive signal to each piezoelectric element 41 is mounted on the wiring substrate 44.

[0127] Next, the detailed structure of the independent flow path P will be described. The shape of the independent flow path Pa and the shape of the independent flow path Pb have a rotationally symmetric relationship centered on the axis of symmetry parallel to the Z axis when viewed from above.

[0128] AsFigure 12 As shown, the independent flow path Pa has a supply flow path Ra1, a pressure chamber Ca1, a first communication flow path Na1, a nozzle flow path Nfa, a second communication flow path Na2, a lateral communication flow path Cq1, and a discharge flow path Ra2. The independent flow path Pa is a flow path formed integrally by these elements, and is a flow path in which the aforementioned elements are connected in the aforementioned order.

[0129] The supply flow path Ra1 is a space formed in the connection plate 33. Specifically, as Figure 12 shown, the supply flow path Ra1 extends along the Z-axis from the space O12 constituting the first common liquid chamber R1 to the surface Fc2 of the connection plate 33. The end of the supply flow path Ra1 connected to the space O12 is the end E1 of the independent flow path Pa. The supply flow path Ra1 is a flow path that communicates with the pressure chamber Ca1 and guides the ink supplied from the first common liquid chamber R1 to the pressure chamber Ca1. The supply flow path Ra1 is an example of the "first independent supply flow path".

[0130] As Figure 12 shown, the first communication flow path Na1 is a space penetrating the connection plate 33. The first communication flow path Na1 is a flow path along the Z-axis. The first communication flow path Na1 extends in the Z1 direction and communicates with the pressure chamber Ca1 and the nozzle flow path Nfa. The first communication flow path Na1 is a flow path that guides the ink extruded from the pressure chamber Ca1 to the nozzle flow path Nfa.

[0131] The nozzle flow path Nfa is a flow path provided in the connection plate 33 and extending in the X-axis direction. When observed in the Z-axis direction, the nozzle flow path Nfa is located between the first communication flow path Na1 and the second communication flow path Na2. The nozzle Na is provided on the nozzle flow path Nfa.

[0132] The second communication flow path Na2 is a space provided in the connection plate 33. The second communication flow path Na2 is a flow path along the Z-axis. The second communication flow path Na2 extends in the Z1 direction and communicates with the lateral communication flow path Cq1 and the nozzle flow path Nfa. The second communication flow path Na2 is a flow path that guides the ink supplied from the nozzle flow path Nfa to the lateral communication flow path Cq1.

[0133] The lateral communication flow path Cq1 is a space provided in the connection plate 33. The lateral communication flow path Cq1 is a long strip flow path along the X-axis. The lateral communication flow path Cq1 extends in the X1 direction and communicates with the second communication flow path Na2 and the discharge flow path Ra2. The lateral communication flow path Cq1 is a flow path that guides the ink introduced from the second communication flow path Na2 to the discharge flow path Ra2.

[0134] The discharge channel Ra2 is a space provided in the connection plate 33. The end of the discharge channel Ra2 connected to the space O22 is the end E2 of the independent channel Pa. The discharge channel Ra2 is a channel that communicates with the lateral connection channel Cq1 and guides the ink introduced from the lateral connection channel Cq1 to the second common liquid chamber R2. The discharge channel Ra2 is an example of the "first independent discharge channel".

[0135] As Figure 13 shown, the independent channel Pb has a supply channel Rb1, a lateral connection channel Cq2, a third connection channel Nb1, a nozzle channel Nfb, a fourth connection channel Nb2, a pressure chamber Cb1, and a discharge channel Rb2. The independent channel Pb is a channel formed by integrating these elements, and is a channel in which the aforementioned elements are connected in the aforementioned order.

[0136] The supply channel Rb1 is a space provided in the connection plate 33. The end of the supply channel Rb1 connected to the space O12 is the end E1 of the independent channel Pb. The supply channel Rb1 is a channel that communicates with the lateral connection channel Cq2 and guides the ink supplied from the first common liquid chamber R1 to the lateral connection channel Cq2. The supply channel Rb1 is an example of the "second independent supply channel".

[0137] The lateral connection channel Cq2 is a space provided in the connection plate 33. The lateral connection channel Cq2 is a long channel along the X-axis. The lateral connection channel Cq2 extends in the X1 direction and communicates with the supply channel Rb1 and the third connection channel Nb1. The lateral connection channel Cq2 is a channel that guides the ink supplied from the supply channel Rb1 to the third connection channel Nb1.

[0138] As Figure 13 shown, the third connection channel Nb1 is a space provided in the connection plate 33. The third connection channel Nb1 is a channel along the Z-axis. The third connection channel Nb1 extends in the Z1 direction and communicates with the lateral connection channel Cq2 and the nozzle channel Nfb. The third connection channel Nb1 is a channel that guides the ink supplied from the lateral connection channel Cq2 to the nozzle channel Nfb.

[0139] The nozzle channel Nfb is a channel provided in the connection plate 33 and extending in the X-axis direction. When viewed in the Z-axis direction, the nozzle channel Nfb is located between the third connection channel Nb1 and the fourth connection channel Nb2. The nozzle Nb is provided on the nozzle channel Nfb.

[0140] The fourth communication channel Nb2 is a space penetrating through the connection plate 33. The fourth communication channel Nb2 is a channel along the Z-axis. The fourth communication channel Nb2 extends and exists in the Z1 direction and communicates with the pressure chamber Cb1 and the nozzle channel Nfb. The fourth communication channel Nb2 is a channel that guides the ink supplied from the nozzle channel Nfb to the pressure chamber Cb1.

[0141] The discharge channel Rb2 is a space provided in the connection plate 33. The end of the discharge channel Rb2 connected to the space O22 is the end E2 of the independent channel Pb. The discharge channel Rb2 is a channel that communicates with the pressure chamber Cb1 and guides the ink extruded from the pressure chamber Cb1 to the second common liquid chamber R2. The discharge channel Rb2 is an example of the "second independent discharge channel".

[0142] In Figure 12 and Figure 13 for the adjacent independent channels Pa and Pb, in the pressure chamber Ca1 or the lateral communication channel Cq1 of the independent channel Pa, there is no channel at the adjacent position in the Y-axis direction. In addition, in the pressure chamber Cb1 or the lateral communication channel Cq2 of the independent channel Pb, there is also no channel at the adjacent position in the Y-axis direction. Therefore, compared with the first embodiment and the second embodiment, even if the pitch θ is reduced, structural crosstalk is not likely to occur. Therefore, the pitch θ can be reduced, and the nozzle resolution in the Z-axis direction can be improved, so that a high-quality image can be recorded.

[0143] In the liquid ejection head 24 of the third embodiment, the cross-sectional area of the nozzle channel Nfa when observed in the X-axis direction is smaller than the cross-sectional areas of the first communication channel Na1 and the second communication channel Na2 when observed in the Z-axis direction. In addition, the cross-sectional area of the nozzle channel Nfb when observed in the X-axis direction is smaller than the cross-sectional areas of the third communication channel Nb1 and the fourth communication channel Nb2 when observed in the Z-axis direction.

[0144] The reason for adopting the above structure will be described. In the following description, for simplicity, only the nozzle channels Nfa and Nfb, the first communication channel Na1, and the third communication channel Nb1 will be described. Although the second communication channel Na2 and the fourth communication channel Nb2 are not specifically described, the relationship between the nozzle channels Nfa and Nfb is the same as that of the first communication channel Na1 and the third communication channel Nb1.

[0145] In the third embodiment, regarding the overlapping width of the first communication channel Na1 and the third communication channel Nb1 in the Z1 direction, since the third communication channel Nb1 is shorter than the first communication channel Na1 in the Z1 direction, the width becomes hb2 of the third communication channel Nb1. That is, the overlapping width Wa in the X1 direction of the nozzle channels Nfa and Nfb is greater than the overlapping width hb2 in the Z1 direction of the first communication channel Na1 and the third communication channel Nb1. Therefore, in order to reduce structural crosstalk, the widths of the nozzle channels Nfa and Nfb in the Y-axis direction are set to relatively small values.

[0146] On the other hand, regarding the first communication channel Na1 and the third communication channel Nb1, since the overlapping width in the Z1 direction is small and thus less susceptible to the influence of structural crosstalk, the cross-sectional area in the Y-axis direction is made relatively large. Thereby, an increase in flow channel resistance is suppressed.

[0147] As described above, according to the third embodiment, it is possible to reduce structural crosstalk in the nozzle channels while suppressing an increase in flow channel resistance in each communication channel.

[0148] In addition, when the overlapping width Wa in the X1 direction of the nozzle channels Nfa and Nfb is smaller than the overlapping width hb2 in the Z1 direction of the first communication channel Na1 and the third communication channel Nb1, it is only necessary to make the widths of the nozzle channels Nfa and Nfb in the Y-axis direction large and make the widths of the first communication channel Na1 and the third communication channel Nb1 in the Y-axis direction small.

[0149] D: Other Embodiments

[0150] The liquid ejection head 24 is not limited to the structures illustrated in the foregoing first to third embodiments. The liquid ejection head 24 may also have a structure in which two or more structures arbitrarily selected from the structures illustrated in the first to third embodiments are combined within a non-contradictory range.

[0151] E: Modification Examples

[0152] Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above embodiments and various modifications can be made. Hereinafter, specific modification methods that can be applied to the foregoing methods are exemplified. Modes arbitrarily selected from the following examples can also be appropriately combined within a non-contradictory range. In addition, in the following examples, among the independent channels Pa and Pb having the same structure, the structure of the independent channel Pa is mainly used as a representative for description.

[0153] Modification 1

[0154] Figure 14 For the modification example Figure 2 The liquid ejection head 24 is not limited to Figures 2 to 13 For example, Figure 14 As shown, the liquid ejection head 24 may be configured such that the nozzle flow path Nfa is provided in the nozzle substrate 31. In the case of this configuration, it is preferable that the following relations 1 and 2 are satisfied.

[0155] Relation 1: If ha≤Wa, then A≥B.

[0156] Relationship 2: If ha>Wa, then A<B.

[0157] In addition, the aforementioned "A" is the flow channel cross-sectional area on the XY plane of the first communication flow channel Na1, and "B" is the flow channel cross-sectional area on the ZY plane of the nozzle flow channel Nfa. The definitions of "A" and "B" are the same in the following description.

[0158] Modification 2

[0159] Figure 15 For the modification example Figure 2 Although the above-mentioned method illustrates a structure in which the nozzle flow channel Nfa is provided in the connecting plate 33, it is also possible to Figure 15 As shown, the nozzle flow path Nfa is provided so as to straddle the nozzle substrate 31 and the communication plate 33. In the case of this structure, it is preferable that the above-mentioned relationship 1 and relationship 2 are satisfied.

[0160] Modification 3

[0161] Figure 16 For the modification example Figure 2 Although the above-mentioned method illustrates a structure in which the nozzle substrate 31 is disposed on the connecting plate 33, a connecting plate 46 may be disposed between the nozzle substrate 31 and the connecting plate 33. In this case, Figure 16 As shown, the nozzle flow path Nfa is provided in the communication plate 46. In the case of the structure illustrated in Modification 3, it is preferable to satisfy the above-mentioned Relation 1 and Relation 2. The communication plate 46 is an example of the "second communication plate" in the claims.

[0162] Modification 4

[0163] Figure 17 For the modification example Figure 2 The cross-sectional view of line aa, Figure 18 for Figure 17Partial cross-sectional view of the e-e line. Although in the foregoing manner, a structure in which the width in the Z1 direction of the first communication flow path Na1 and the width in the Z1 direction of the second communication flow path Na2 are the same is illustrated, the widths in the Z1 direction of the first communication flow path Na1 and the second communication flow path Na2 may also be different from each other. In the case of this structure, for example, as Figure 17 shown, the width ha1 in the Z1 direction of the first communication flow path Na1 is greater than the width ha2 in the Z1 direction of the second communication flow path Na2. Further, as Figure 18 shown, the width Da1 in the Y2 direction of the first communication flow path Na1 is less than the width Da2 in the Y2 direction of the second communication flow path Na2. According to this structure, the same operational effects as those of the first embodiment can be obtained. In addition, when the structure according to Modification 4 is adopted in the liquid ejection head 24, it is preferable that the following Relationships 3 to 8 are satisfied. Further, "C" described later is the cross-sectional area of the flow path on the XY plane of the second communication flow path Na2.

[0164] Relationship 3: If ha1 ≤ Wa ≤ ha2, then A ≥ B ≥ C.

[0165] Relationship 4: If ha1 < Wa < ha2, then A > B > C.

[0166] Relationship 5: If Wa ≤ ha2 < ha1, then B ≥ C > A.

[0167] Relationship 6: If Wa < ha1 < ha2, then B > A > C.

[0168] Relationship 7: If ha2 < ha1 ≤ Wa, then C > A ≥ B.

[0169] Relationship 8: If ha2 < Wa < ha1, then C > B > A.

[0170] Modification 5

[0171] Figure 19 is a schematic view showing the flow path structure inside the liquid ejection head 24 when observing the liquid ejection head 24 related to the modification from the Z axis. Figure 20 is Figure 19 a cross-sectional view of the a-a line of Figure 21 is Figure 19 a cross-sectional view of the b-b line of

[0172] Although in the foregoing manner, the liquid ejection head 24 is provided with the pressure chambers Ca1 and Cb1 on the upstream side in the direction in which the ink circulates, and the pressure chambers Ca2 and Cb2 on the downstream side, the pressure chambers Ca2 and Cb2 may be provided on the upstream side, and the pressure chambers Ca1 and Cb1 may be provided on the downstream side.

[0173] In the case of this structure, as Figure 20 shown, the supply flow path Ra1 is a flow path that communicates with the pressure chamber Ca2 and guides the ink supplied from the first common liquid chamber R1 to the pressure chamber Ca2. Similarly, as Figure 21 shown, the supply flow path Rb1 is a flow path that communicates with the pressure chamber Cb2 and guides the ink supplied from the first common liquid chamber R1 to the pressure chamber Cb2. The supply flow path 265 according to Modification 5 supplies the liquid to the supply flow path Ra1 and the supply flow path Rb1 in common.

[0174] In addition, as Figure 20 shown, the discharge flow path Ra2 of the liquid ejection head 24 according to Modification 5 is a flow path that communicates with the pressure chamber Ca1 and guides the ink extruded from the pressure chamber Ca1 to the second common liquid chamber R2. Similarly, as Figure 21 shown, the discharge flow path Rb2 is a flow path that communicates with the pressure chamber Cb1 and guides the ink extruded from the pressure chamber Cb1 to the second common liquid chamber R2. The circulation flow path 264 according to Modification 5 is a flow path that connects the second common liquid chamber R2 and the storage container 263, and discharges the ink in common from the discharge flow path Ra2 and the discharge flow path Rb2 via the second common liquid chamber R2.

[0175] Modification 6

[0176] The energy generating element that changes the pressure of the ink in the pressure chamber C is not limited to the piezoelectric element 41 illustrated in the foregoing manner. For example, a heating element that changes the pressure of the ink by generating bubbles inside the pressure chamber C by using heating may also be used as the energy generating element.

[0177] Modification 7

[0178] Although in the foregoing manner, the serial liquid ejection device 100 that reciprocates the conveyor 231 on which the liquid ejection head 24 is mounted is illustrated, the present invention can also be applied to a line-type liquid ejection device in which a plurality of nozzles N are distributed across the entire width of the medium 11.

[0179] F: Supplementary

[0180] The structure of the liquid ejection device 100 is not limited to Figures 2 to 21The structures exemplified herein, for example, may also be general liquid ejection devices that circulate ink, other than the structures shown in these drawings. Moreover, among the liquid ejection devices 100 exemplified in the foregoing manner, in addition to devices dedicated to printing, they may also be adopted by various devices such as facsimile machines or copiers, and the uses of the present invention are not particularly limited. Of course, the uses of the liquid ejection device are not limited to printing. For example, a liquid ejection device that ejects a solution of a color material can be used as a manufacturing device for forming a color filter of a display device such as a liquid crystal display panel. In addition, a liquid ejection device that ejects a solution of a conductive material can be used as a manufacturing device for forming wirings or electrodes of a wiring substrate. In addition, a liquid ejection device that ejects a solution of an organism-related organic substance can be used, for example, as a manufacturing device for manufacturing a biochip.

[0181] Moreover, the effects described in this specification are ultimately illustrative or exemplary effects and are not limiting. That is, for those skilled in the art, according to the description of this specification, the present invention can achieve the above effects or, instead of the above effects, achieve other obvious effects.

[0182] Although the preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to the examples involved. It is obvious that those with ordinary knowledge in the technical field of the present invention can conceive of various modification examples or correction examples within the scope of the technical idea described in the claims, and for these situations, it is clearly understood that they also belong to the technical scope of the present invention.

[0183] G: Postscript

[0184] From the foregoing exemplified manner, for example, the following structures can be grasped.

[0185] In addition, in this application, when element A and element B "overlap" when observed in a specific direction, it means that at least a part of element A overlaps at least a part of element B when observed along this direction. It is not necessary for all of element A to overlap all of element B. As long as at least a part of element A overlaps at least a part of element B, it can be interpreted as "element A overlaps element B".

[0186] One aspect (Aspect 1) of the present disclosure relates to a liquid ejection head including: a first pressure chamber that extends in a first direction and applies pressure to a liquid; a second pressure chamber that extends in the first direction and applies pressure to the liquid; a first nozzle flow path that extends in the first direction and is provided with a first nozzle for ejecting the liquid; a first communication flow path that extends in a second direction intersecting the first direction and communicates with the first pressure chamber and the first nozzle flow path; and a second communication flow path that extends in the second direction and communicates with the second pressure chamber and the first nozzle flow path. The width of the first nozzle flow path in the first direction is greater than the width of the first communication flow path in the second direction, and the width of the first nozzle flow path in a third direction intersecting the first direction and the second direction is smaller than the width of the first communication flow path in the third direction. According to this aspect, it is possible to reduce structural crosstalk in the first nozzle flow path while suppressing an increase in flow path resistance in the first communication flow path.

[0187] According to a specific example of Aspect 1 (Aspect 2), it further includes: a third pressure chamber that extends in the first direction and applies pressure to the liquid; a fourth pressure chamber that extends in the first direction and applies pressure to the liquid; a second nozzle flow path that extends in the first direction and is provided with a second nozzle for ejecting the liquid; a third communication flow path that extends in the second direction and communicates with the third pressure chamber and the second nozzle flow path; and a fourth communication flow path that extends in the second direction and communicates with the fourth pressure chamber and the second nozzle flow path. The width of the second nozzle flow path in the first direction is greater than the width of the third communication flow path in the second direction, and the width of the second nozzle flow path in the third direction is smaller than the width of the third communication flow path in the third direction. According to this aspect, it is possible to reduce structural crosstalk in the second nozzle flow path while suppressing an increase in flow path resistance in the second communication flow path.

[0188] According to a specific example of Aspect 2 (Aspect 3), the first nozzle flow path and the second nozzle flow path are adjacent in the third direction.

[0189] According to a specific example of Aspect 3 (Aspect 4), the thickness of a partition wall provided between the first nozzle flow path and the second nozzle flow path is thicker than the thickness of a partition wall provided between the first communication flow path and the third communication flow path. According to this aspect, even if vibration occurs in one of the nozzle flow paths in the first nozzle flow path and the second nozzle flow path, it is difficult to propagate to the other nozzle flow path. Therefore, structural crosstalk between the first communication flow path and the third communication flow path is reduced.

[0190] According to a specific example (Mode 5) of any one of Modes 2 to 4, there is further provided: a first independent supply flow path that communicates with the first pressure chamber and supplies liquid to the first pressure chamber; a second independent supply flow path that communicates with the third pressure chamber and supplies liquid to the third pressure chamber; a common supply flow path that supplies liquid to the first independent supply flow path and the second independent supply flow path in common; a first independent discharge flow path that communicates with the second pressure chamber and discharges liquid from the second pressure chamber; a second independent discharge flow path that communicates with the fourth pressure chamber and discharges liquid from the fourth pressure chamber; and a common discharge flow path that discharges liquid from the first independent discharge flow path and the second independent discharge flow path in common.

[0191] According to a specific example (Mode 6) of any one of Modes 2 to 4, there is further provided: a first independent supply flow path that communicates with the second pressure chamber and supplies liquid to the second pressure chamber; a second independent supply flow path that communicates with the fourth pressure chamber and supplies liquid to the fourth pressure chamber; a common supply flow path that supplies liquid to the first independent supply flow path and the second independent supply flow path in common; a first independent discharge flow path that communicates with the third pressure chamber and discharges liquid from the third pressure chamber; a second independent discharge flow path that communicates with the first pressure chamber and discharges liquid from the first pressure chamber; and a common discharge flow path that discharges liquid from the first independent discharge flow path and the second independent discharge flow path in common.

[0192] According to a specific example (Mode 7) of any one of Modes 1 to 6, the width of the first nozzle flow path in the first direction is greater than the width of the second communication flow path in the second direction, and the width of the first nozzle flow path in the third direction is less than the width of the second communication flow path in the second direction. According to this mode, it is possible to reduce structural crosstalk in the first nozzle flow path while suppressing an increase in flow path resistance in the second communication flow path.

[0193] According to a specific example (Mode 8) of any one of Modes 1 to 7, the width of the first communication flow path in the second direction is greater than the width of the second communication flow path in the second direction, and the width of the first communication flow path in the third direction is less than the width of the second communication flow path in the third direction.

[0194] According to a specific example (Mode 9) of any one of Modes 1 to 8, the cross-sectional area of the first nozzle flow path when observed from the first direction is smaller than the cross-sectional area of the first communication flow path when observed from the second direction.

[0195] According to a specific example (Mode 10) of any one of Modes 1 to 9, it further includes: a pressure chamber substrate in which the first pressure chamber and the second pressure chamber are formed; a first communication plate in which the first communication flow path and the second communication flow path are formed; and a nozzle substrate on which the first nozzle is formed.

[0196] According to the specific example (Mode 11) of Mode 10, the first nozzle flow path is formed in the first communication plate.

[0197] According to the specific example (Mode 12) of Mode 10, the first nozzle flow path is formed in the nozzle substrate.

[0198] According to the specific example (Mode 13) of Mode 10, the first nozzle flow path is formed so as to straddle the first communication plate and the nozzle substrate.

[0199] According to the specific example (Mode 14) of Mode 10, it further includes a second communication plate in which the first nozzle flow path is provided, and the second communication plate is disposed between the first communication plate and the nozzle substrate.

[0200] According to the specific example (Mode 15) of Mode 10, the width of the first communication flow path in the second direction is different from the width of the second communication flow path in the second direction.

[0201] According to a specific example (Mode 16) of any one of Modes 1 to 15, it further includes: a first energy generating element that generates energy for applying pressure to the liquid in the first pressure chamber by being applied a driving voltage; and a second energy generating element that generates energy for applying pressure to the liquid in the second pressure chamber by being applied a driving voltage.

[0202] A liquid ejecting head according to one mode (Mode 17) of the present disclosure includes: a first pressure chamber that extends in a first direction and applies pressure to a liquid; a second pressure chamber that extends in the first direction and applies pressure to the liquid; a first nozzle flow path that extends in the first direction and is provided with a first nozzle for ejecting the liquid; a first communication flow path that extends in a second direction intersecting the first direction and communicates with the first pressure chamber and the first nozzle flow path; and a second communication flow path that extends in the second direction and communicates with the second pressure chamber and the first nozzle flow path, the width of the first nozzle flow path in the first direction is greater than the width of the first communication flow path in the second direction, and the cross-sectional area of the first nozzle flow path when observed from the first direction is smaller than the cross-sectional area of the first communication flow path when observed from the second direction.

[0203] A liquid ejection head according to one embodiment (Embodiment 18) of the present disclosure includes: a first pressure chamber that extends in a first direction and applies pressure to a liquid; a second pressure chamber that extends in the first direction and applies pressure to the liquid; a first nozzle flow path that extends in the first direction and is provided with a first nozzle for ejecting the liquid; a first communication flow path that extends in a second direction intersecting the first direction and communicates with the first pressure chamber and the first nozzle flow path; a second communication flow path that extends in the second direction and communicates with the second pressure chamber and the first nozzle flow path, wherein a width of the first nozzle flow path in the first direction is smaller than a width of the first communication flow path in the second direction, and a width of the first nozzle flow path in a third direction intersecting the first direction and the second direction is larger than a width of the first communication flow path in the third direction. According to this embodiment, it is possible to reduce structural crosstalk in the first communication flow path while suppressing an increase in flow path resistance in the first nozzle flow path.

[0204] A liquid ejection head according to one embodiment (Embodiment 19) of the present disclosure includes: a first pressure chamber that extends in a first direction and applies pressure to a liquid; a second pressure chamber that extends in the first direction and applies pressure to the liquid; a first nozzle flow path that extends in the first direction and is provided with a first nozzle for ejecting the liquid; a first communication flow path that extends in a second direction intersecting the first direction and communicates with the first pressure chamber and the first nozzle flow path; a second communication flow path that extends in the second direction and communicates with the second pressure chamber and the first nozzle flow path, wherein a width of the first nozzle flow path in the first direction is smaller than a width of the first communication flow path in the second direction, and a cross-sectional area of the first nozzle flow path when observed from the first direction is larger than a cross-sectional area of the first communication flow path when observed from the second direction.

[0205] A liquid ejection device according to one embodiment (Embodiment 20) of the present disclosure includes: the liquid ejection head according to any one of Embodiments 1 to 19; and a control unit that controls an ejection operation of the liquid ejection head.

[0206] Symbol Description

[0207] 41... piezoelectric element; 264... circulation flow path; 265... supply flow path; pressure chambers... C, Ca, Cb, Ca1, Ca2, Cb1, Cb2; Na1... first communication flow path; Na2... second communication flow path; Nb1... third communication flow path; Nb2... fourth communication flow path; Nfa, Nfb... nozzle flow paths; Ra1, Rb1... supply flow paths; Ra2, Rb2... discharge flow paths.

Claims

1. A liquid ejection head, characterized in that, Comprising: A first pressure chamber that extends in a first direction and applies pressure to a liquid; A second pressure chamber that extends in the first direction and applies pressure to a liquid; A first nozzle flow path that extends in the first direction and is provided with a first nozzle for ejecting a liquid; A first communication flow path that extends in a second direction intersecting the first direction and communicates with the first pressure chamber and the first nozzle flow path; A second communication flow path that extends in the second direction and communicates with the second pressure chamber and the first nozzle flow path, When ejecting a liquid from the first nozzle, a flow of the liquid flowing sequentially through the first pressure chamber, the first communication flow path, the first nozzle flow path, the second communication flow path, and the second pressure chamber is formed, The width of the first nozzle flow path in the first direction is greater than the width of the first communication flow path in the second direction, The width of the first nozzle flow path in a third direction intersecting the first direction and the second direction is smaller than the width of the first communication flow path in the third direction.

2. The liquid ejection head according to claim 1, wherein Further comprising: A third pressure chamber that extends in the first direction and applies pressure to a liquid; A fourth pressure chamber that extends in the first direction and applies pressure to a liquid; A second nozzle flow path that extends in the first direction and is provided with a second nozzle for ejecting a liquid; A third communication flow path that extends in the second direction and communicates with the third pressure chamber and the second nozzle flow path; A fourth communication flow path that extends in the second direction and communicates with the fourth pressure chamber and the second nozzle flow path, The width of the second nozzle flow path in the first direction is greater than the width of the third communication flow path in the second direction, The width of the second nozzle flow path in the third direction is smaller than the width of the third communication flow path in the third direction.

3. The liquid ejecting head according to claim 2, wherein The first nozzle flow path and the second nozzle flow path are adjacent in the third direction.

4. The liquid ejecting head according to claim 3, wherein The thickness of the partition wall provided between the first nozzle flow path and the second nozzle flow path is thicker than the thickness of the partition wall provided between the first communication flow path and the third communication flow path.

5. The liquid ejection head according to any one of claims 2 to 4, characterized in that, Further comprising: A first independent supply flow path that communicates with the first pressure chamber and supplies a liquid to the first pressure chamber; A second independent supply flow path that communicates with the third pressure chamber and supplies a liquid to the third pressure chamber; A common supply flow path that supplies a liquid to the first independent supply flow path and the second independent supply flow path in common; A first independent discharge flow path that communicates with the second pressure chamber and discharges a liquid from the second pressure chamber; A second independent discharge flow path that communicates with the fourth pressure chamber and discharges a liquid from the fourth pressure chamber; A common discharge flow path that discharges a liquid from the first independent discharge flow path and the second independent discharge flow path in common.

6. The liquid ejection head according to any one of claims 2 to 4, characterized in that, Further comprising: A first independent supply flow path that communicates with the second pressure chamber and supplies a liquid to the second pressure chamber; A second independent supply flow path that communicates with the fourth pressure chamber and supplies liquid to the fourth pressure chamber; A common supply flow path that supplies liquid to the first independent supply flow path and the second independent supply flow path in common; A first independent discharge flow path that communicates with the third pressure chamber and discharges liquid from the third pressure chamber; A second independent discharge flow path that communicates with the first pressure chamber and discharges liquid from the first pressure chamber; A common discharge flow path that discharges liquid from the first independent discharge flow path and the second independent discharge flow path in common.

7. The liquid ejection head according to claim 1, wherein the width of the first nozzle flow path in the first direction is greater than the width of the second communication flow path in the second direction, the width of the first nozzle flow path in the third direction is less than the width of the second communication flow path in the second direction.

8. The liquid ejection head according to claim 1, wherein the width of the first communication flow path in the second direction is greater than the width of the second communication flow path in the second direction, the width of the first communication flow path in the third direction is less than the width of the second communication flow path in the third direction.

9. The liquid ejection head according to claim 1, wherein the cross-sectional area of the first nozzle flow path when observed from the first direction is smaller than the cross-sectional area of the second communication flow path when observed from the second direction.

10. The liquid ejection head according to claim 1, wherein, Further provided with: A pressure chamber substrate in which the first pressure chamber and the second pressure chamber are formed; A first communication plate in which the first communication flow path and the second communication flow path are formed; A nozzle substrate on which the first nozzle is formed.

11. The liquid ejection head according to claim 10, wherein the first nozzle flow path is formed in the first communication plate.

12. The liquid ejection head according to claim 10, wherein the first nozzle flow path is formed in the nozzle substrate.

13. The liquid ejection head according to claim 10, wherein the first nozzle flow path is formed so as to straddle the first communication plate and the nozzle substrate.

14. The liquid ejection head according to claim 10, wherein a second communication plate is further provided, and the first nozzle flow path is provided in the second communication plate, and the second communication plate is provided between the first communication plate and the nozzle substrate.

15. The liquid ejection head according to claim 10, wherein the width of the first communication flow path in the second direction is different from the width of the second communication flow path in the second direction.

16. The liquid ejection head according to claim 1, wherein Further provided with: A first energy generating element that generates energy for applying pressure to the liquid in the first pressure chamber by being applied with a driving voltage; A second energy generating element that generates energy for applying pressure to the liquid in the second pressure chamber by being applied with a driving voltage.

17. A liquid ejection head, characterized in that, Provided with: A first pressure chamber that extends in a first direction and applies pressure to liquid; A second pressure chamber that extends in the first direction and applies pressure to liquid; A first nozzle flow path that extends in the first direction and is provided with a first nozzle for ejecting liquid; A first communication flow path that extends in a second direction intersecting the first direction and communicates with the first pressure chamber and the first nozzle flow path; A second communication flow path that extends in the second direction and communicates with the second pressure chamber and the first nozzle flow path, When liquid is ejected from the first nozzle, a flow of liquid is formed that sequentially passes through the first pressure chamber, the first communication flow path, the first nozzle flow path, the second communication flow path, and the second pressure chamber, The width of the first nozzle flow path in the first direction is greater than the width of the first communication flow path in the second direction, The cross-sectional area of the first nozzle flow path when observed from the first direction is smaller than the cross-sectional area of the first communication flow path when observed from the second direction.

18. A liquid ejection head, characterized in that, Comprising: A first pressure chamber that extends in the first direction and applies pressure to the liquid; A second pressure chamber that extends in the first direction and applies pressure to the liquid; A first nozzle flow path that extends in the first direction and is provided with a first nozzle for ejecting liquid; A first communication flow path that extends in a second direction intersecting the first direction and communicates with the first pressure chamber and the first nozzle flow path; A second communication flow path that extends in the second direction and communicates with the second pressure chamber and the first nozzle flow path, When liquid is ejected from the first nozzle, a flow of liquid is formed that sequentially passes through the first pressure chamber, the first communication flow path, the first nozzle flow path, the second communication flow path, and the second pressure chamber, The width of the first nozzle flow path in the first direction is smaller than the width of the first communication flow path in the second direction, The width of the first nozzle flow path in a third direction intersecting the first direction and the second direction is greater than the width of the first communication flow path in the third direction.

19. A liquid ejection head, characterized in that, Comprising: A first pressure chamber that extends in the first direction and applies pressure to the liquid; A second pressure chamber that extends in the first direction and applies pressure to the liquid; A first nozzle flow path that extends in the first direction and is provided with a first nozzle for ejecting liquid; A first communication flow path that extends in a second direction intersecting the first direction and communicates with the first pressure chamber and the first nozzle flow path; A second communication flow path that extends in the second direction and communicates with the second pressure chamber and the first nozzle flow path, When liquid is ejected from the first nozzle, a flow of liquid is formed that sequentially passes through the first pressure chamber, the first communication flow path, the first nozzle flow path, the second communication flow path, and the second pressure chamber, The width of the first nozzle flow path in the first direction is smaller than the width of the first communication flow path in the second direction, The cross-sectional area of the first nozzle flow path when observed from the first direction is greater than the cross-sectional area of the first communication flow path when observed from the second direction.

20. A liquid ejection device, comprising: The liquid ejection head according to any one of claims 1 to 19; A control unit that controls the ejection operation of the liquid ejection head.

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