Liquid discharge head, and liquid discharge device

Abstract

To solve the problem that when a temperature sensor is provided outside of a liquid discharge head, a difference between a temperature measured by the temperature sensor and a temperature of ink in a pressure chamber becomes larger compared to a difference between a temperature in the liquid discharge head and the temperature of the ink in the pressure chamber.SOLUTION: A liquid discharge head 510 includes: a piezoelectric element 300 including a first electrode 60, a second electrode 80 and a piezoelectric crystal 70; a diaphragm 50 deformed by driving the piezoelectric crystal 300; a pressure chamber substrate 10 provided with a pressure chamber 12 whose capacity changes due to deformation of the diaphragm 50; a wiring board 120; an individual lead electrode 91 for electrically connecting the wiring board 120 and the first electrode 60; a common lead electrode 92 for electrically connecting the wiring board 120 and the second electrode 80; and resistance wiring 401 electrically connected to the wiring board 120 and detecting a temperature of the pressure chamber 12.SELECTED DRAWING: Figure 5

Description

[Technical field]

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

[0002] Patent Document 1 discloses a liquid ejection head having a piezoelectric element, a pressure chamber, and a nozzle communicating with the pressure chamber. This liquid ejection head is provided in a printer, which is an example of a liquid ejection device, and a control unit drives the piezoelectric element to change the volume of the pressure chamber, and ink, which is an example of a liquid supplied to the pressure chamber, is ejected from the nozzle. In addition, the printer is provided with a temperature sensor on the side of the carriage to which the liquid ejection head is attached, which measures the environmental temperature outside the liquid ejection head. The control unit then controls the drive of the piezoelectric element based on the environmental temperature measured by the temperature sensor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2011-104916 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a liquid ejection device such as that disclosed in Patent Document 1, a temperature sensor is provided outside the liquid ejection head. Therefore, there is a risk that the difference between the temperature measured by the temperature sensor and the temperature of the ink in the pressure chamber will be larger than the difference between the temperature in the liquid ejection head and the temperature of the ink in the pressure chamber. In this case, there is a risk that the liquid ejection device will not be able to control the ejection of the liquid ejection head in a manner appropriate to the temperature of the ink in the pressure chamber. [Means for solving the problem]

[0005] The liquid ejection head includes a first electrode, a second electrode, and a piezoelectric body, and in a stacking direction in which the first electrode, the second electrode, and the piezoelectric body are stacked, the piezoelectric body is provided between the first electrode and the second electrode, a vibration plate provided on one side of the stacking direction relative to the piezoelectric element, the vibration plate deforming when the piezoelectric element is driven, a pressure chamber substrate provided on the one side of the stacking direction relative to the vibration plate, the pressure chamber substrate having a plurality of pressure chambers whose volume changes when the vibration plate is deformed, a wiring board, first wiring electrically connecting the wiring board and the first electrode, second wiring electrically connecting the wiring board and the second electrode, and a temperature detection unit electrically connected to the wiring board and for detecting the temperature of the pressure chambers.

[0006] The liquid ejection device includes the liquid ejection head and a control unit that controls the ejection operation of liquid from the liquid ejection head. [Brief description of the drawings]

[0007] [Figure 1] 1 is a block diagram showing a schematic configuration of a liquid ejection device including a liquid ejection head according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is an exploded perspective view showing a detailed configuration of the liquid ejection head. [Diagram 3] FIG. 2 is a plan view showing a liquid ejection head. [Figure 4] 4 is a cross-sectional view showing the IV-IV cross section of the liquid ejection head shown in FIG. [Diagram 5] FIG. 5 is a detailed view of a main part of the liquid ejection head shown in FIG. [Figure 6] 6 is a cross-sectional view showing the liquid ejection head shown in FIG. 3 along the line VI-VI. [Figure 7] FIG. 11 is a detailed view of a main part of a liquid ejection head according to a second embodiment. [Figure 8] FIG. 11 is a detailed view of a main part of a liquid ejection head according to a third embodiment. [Figure 9] FIG. 11 is a plan view showing a liquid ejection head according to a fourth embodiment. [Figure 10] FIG. 11 is a plan view showing a modified example of the liquid ejection head according to the fourth embodiment. [Figure 11] FIG. 11 is a plan view showing a modified example of the liquid ejection head according to the fourth embodiment. [Figure 12] FIG. 11 is a plan view showing a liquid ejection head according to a fifth embodiment. [Figure 13] FIG. 11 is a detailed view of a main part of a liquid ejection head according to another embodiment. [Figure 14] FIG. 11 is a cross-sectional view of a liquid ejection head according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, the present invention will be described based on an embodiment. In each drawing, the same members are given the same reference numerals, and duplicated explanations will be omitted.

[0009] In each figure, X, Y, and Z represent three spatial axes that are mutually orthogonal. In this specification, the directions along these axes are the X-axis direction, the Y-axis direction, and the Z-axis direction. When specifying a direction, the positive direction is "+" and the negative direction is "-", and the direction notation is both positive and negative, with the direction indicated by the arrow in each figure being the + direction and the opposite direction to the arrow being the - direction. The Z direction indicates the vertical direction, with the +Z direction being vertically downward and the -Z direction being vertically upward. Furthermore, the three spatial axes X, Y, and Z that are not limited to positive and negative directions will be described as the X-axis, Y-axis, and Z-axis.

[0010] 1. Embodiment 1 In this embodiment, the liquid ejection device 500 is configured as an inkjet printer, and forms an image by ejecting ink onto printing paper P. Ink is an example of a liquid. Note that instead of printing paper P, any type of medium, such as a resin film or fabric, may be used as the target onto which the ink is ejected.

[0011] As shown in FIG. 1, the liquid ejection device 500 includes a liquid ejection head 510, an ink tank 550, a transport mechanism 560, a moving mechanism 570, and a control unit 580.

[0012] The liquid ejection head 510 has a large number of nozzles 21, and ejects ink in the +Z direction to form an image on the printing paper P. The liquid ejection head 510 also has resistive wiring 401, which is an example of a temperature detection unit. A detailed configuration of the liquid ejection head 510 will be described later. The ejected ink may be, for example, a total of four colors of ink, namely black, cyan, magenta, and yellow. Note that the ink may be ejected in any color, such as light cyan, light magenta, and white, without being limited to the above four colors. The liquid ejection head 510 is mounted on a carriage 572, which will be described later, of the moving mechanism 570, and moves back and forth in the main scanning direction together with the movement of the carriage 572. In this embodiment, the main scanning direction is the +X direction and the -X direction.

[0013] The ink tank 550 contains ink to be ejected from the liquid ejection head 510. The ink tank 550 is not mounted on the carriage 572. The ink tank 550 and the liquid ejection head 510 are connected by a resin tube 552, and ink is supplied from the ink tank 550 to the liquid ejection head 510 via the tube 552. Instead of the ink tank 550, a bag-shaped liquid pack made of a flexible film may be used.

[0014] The transport mechanism 560 transports the print paper P in the sub-scanning direction, which is a direction perpendicular to the X-axis direction, which is the main scanning direction, and which corresponds to the +Y direction and -Y direction in this embodiment. The transport mechanism 560 includes a transport rod 564 to which three transport rollers 562 are attached, and a transport motor 566 that rotates the transport rod 564. The transport motor 566 rotates the transport rod 564, thereby rotating the multiple transport rollers 562 and transporting the print paper P in the +Y direction in the sub-scanning direction. The number of transport rollers 562 is not limited to three, and may be any number. Also, a configuration may be provided with multiple transport mechanisms 560.

[0015] The movement mechanism 570 includes a conveyor belt 574, a movement motor 576, and a pulley 577 in addition to the above-mentioned carriage 572. The carriage 572 mounts the liquid ejection head 510 in a state in which it is capable of ejecting ink. The carriage 572 is attached to the conveyor belt 574. The conveyor belt 574 is stretched between the movement motor 576 and the pulley 577. The movement motor 576 is driven to rotate, so that the conveyor belt 574 moves back and forth in the main scanning direction. As a result, the carriage 572 attached to the conveyor belt 574 also moves back and forth in the main scanning direction.

[0016] The control unit 580 controls the entire liquid ejection device 500. For example, the control unit 580 controls the reciprocating movement of the carriage 572 in the main scanning direction, the transporting movement of the printing paper P in the sub-scanning direction, and the ejection movement of the liquid ejection head 510. In this embodiment, the control unit 580 detects the temperature of the pressure chamber 12, which will be described later, based on a measurement value measured by a temperature detection unit included in the liquid ejection head 510. The control unit 580 also functions as a drive control unit for the piezoelectric element 300, which will be described later. That is, the control unit 580 controls the ejection of ink onto the printing paper P by outputting a drive signal based on the detected temperature of the pressure chamber 12 to the liquid ejection head 510 to drive the piezoelectric element 300. The control unit 580 may be configured, for example, with one or more processing circuits such as a CPU (Central Processing Unit) or an FPGA (Field Programmable Gate Array) and one or more storage circuits such as a semiconductor memory.

[0017] 2, the liquid ejection head 510 ejects ink droplets in the Z-axis direction, more specifically, in the +Z direction. The liquid ejection head 510 has, as its components, a pressure chamber substrate 10, a communication plate 15, a nozzle plate 20, a compliance substrate 45, a vibration plate 50 (described later), a piezoelectric element 300 (described later), a protective substrate 30, a case member 40, and a wiring substrate 120. The pressure chamber substrate 10, the communication plate 15, the nozzle plate 20, the compliance substrate 45, the vibration plate 50, the piezoelectric element 300, the protective substrate 30, and the case member 40 can also be considered as an example of a laminated member that forms the liquid ejection head 510 by being laminated.

[0018] The pressure chamber substrate 10 is made of, for example, a silicon substrate, a glass substrate, an SOI substrate, various ceramic substrates, etc. The pressure chamber substrate 10 can also be considered an example of a substrate.

[0019] As shown in FIG. 3, the pressure chamber substrate 10 has two pressure chamber rows in the X-axis direction, in which a plurality of pressure chambers 12 are arranged along the Y-axis direction. In other words, the liquid ejection head 510 has a plurality of pressure chambers 12, and the plurality of pressure chambers 12 form a pressure chamber row in which the plurality of pressure chambers 12 are arranged along the Y-axis direction. The Y-axis direction is an example of a first direction, and the X-axis direction is an example of a second direction. The pressure chamber row is an example of a pressure chamber group. Of the two pressure chamber rows, the pressure chamber row on the +X direction side is also called the first pressure chamber row, and the pressure chamber row separated from the first pressure chamber row in the -X direction in the X-axis direction is also called the second pressure chamber row. The +X direction is an example of one of the second directions, and the -X direction is an example of the other of the second directions. Although FIG. 3 is a plan view of the liquid ejection head 510, the configuration around the pressure chamber substrate 10 is described, and for convenience of explanation, the protective substrate 30 and the case member 40 are also omitted.

[0020] The multiple pressure chambers 12 constituting each pressure chamber row are arranged on a straight line along the Y axis direction so that they are positioned at the same position in the X axis direction. Pressure chambers 12 adjacent to each other in the Y axis direction are partitioned by partition walls 11 shown in Fig. 6. Of course, the arrangement of the pressure chambers 12 is not particularly limited. For example, the arrangement of the multiple pressure chambers 12 lined up in the Y axis direction may be a so-called staggered arrangement in which every other pressure chamber 12 is shifted in the X axis direction.

[0021] Furthermore, the pressure chamber 12 in this embodiment is formed, for example, in a rectangular shape, with the length in the X-axis direction being longer than the length in the Y-axis direction when viewed in a plan view from the +Z direction. Of course, the shape of the pressure chamber 12 when viewed in a plan view from the +Z direction is not particularly limited, and may be a parallelogram, polygon, circle, oval, or the like. Note that the oval shape referred to here refers to a shape that is based on a rectangular shape and has semicircular ends at both longitudinal ends, and includes a rounded rectangular shape, an elliptical shape, an egg shape, and the like.

[0022] As shown in FIGS. 2 and 4, on the +Z direction side of the pressure chamber substrate 10, a communication plate 15, a nozzle plate 20, and a compliance substrate 45 are laminated in this order.

[0023] The communicating plate 15 is provided with nozzle communicating passages 16 that communicate between the pressure chambers 12 and the nozzles 21. The communicating plate 15 is also provided with a first manifold portion 17 and a second manifold portion 18 that constitute a part of a manifold 100 that serves as a common liquid chamber to which the multiple pressure chambers 12 communicate. The first manifold portion 17 is provided so as to penetrate the communicating plate 15 in the Z-axis direction. The second manifold portion 18 is provided so as to open on the surface on the +Z direction side, without penetrating the communicating plate 15 in the Z-axis direction.

[0024] Furthermore, in the communicating plate 15, a supply communication passage 19 that communicates with one end of the pressure chamber 12 in the X-axis direction is provided independently for each pressure chamber 12. The supply communication passage 19 communicates between the second manifold portion 18 and each pressure chamber 12, and supplies ink in the manifold 100 to each pressure chamber 12.

[0025] The communicating plate 15 may be a silicon substrate, a glass substrate, an SOI substrate, various ceramic substrates, a metal substrate, or the like. An example of a metal substrate is a stainless steel substrate. It is preferable that the communicating plate 15 is made of a material having substantially the same thermal expansion coefficient as that of the pressure chamber substrate 10. This makes it possible to suppress warping of the pressure chamber substrate 10 and the communicating plate 15 caused by the difference in thermal expansion coefficient when the temperatures of the pressure chamber substrate 10 and the communicating plate 15 change.

[0026] The nozzle plate 20 is provided on the side of the communication plate 15 opposite to the pressure chamber substrate 10, i.e., on the +Z direction side. Nozzles 21 that communicate with each pressure chamber 12 via nozzle communication paths 16 are formed in the nozzle plate 20.

[0027] In this embodiment, the multiple nozzles 21 are arranged in a line along the Y-axis direction. The nozzle plate 20 has two nozzle rows, each row having the multiple nozzles 21 arranged therein, spaced apart in the X-axis direction. The two nozzle rows correspond to a first pressure chamber row and a second pressure chamber row, respectively. The multiple nozzles 21 in each row are arranged to be at the same position in the X-axis direction. The arrangement of the nozzles 21 is not particularly limited. For example, the nozzles 21 arranged in a line in the Y-axis direction may be arranged at positions shifted in the X-axis direction by every other nozzle 21.

[0028] The material of the nozzle plate 20 is not particularly limited, and may be, for example, a silicon substrate, a glass substrate, an SOI substrate, various ceramic substrates, or a metal substrate. Examples of metal substrates include stainless steel substrates. Furthermore, organic materials such as polyimide resins may be used as the material of the nozzle plate 20. However, it is preferable that the nozzle plate 20 is made of a material having a thermal expansion coefficient substantially equal to that of the communication plate 15. This makes it possible to suppress warping of the nozzle plate 20 and the communication plate 15 caused by the difference in thermal expansion coefficient when the temperature of the nozzle plate 20 and the communication plate 15 changes.

[0029] The compliance substrate 45 is provided together with the nozzle plate 20 on the side of the communication plate 15 opposite to the pressure chamber substrate 10, i.e., on the surface on the +Z direction side. The compliance substrate 45 is provided around the nozzle plate 20 and seals the openings of the first manifold portion 17 and the second manifold portion 18 provided in the communication plate 15. In this embodiment, the compliance substrate 45 includes a sealing film 46 made of a flexible thin film and a fixed substrate 47 made of a hard material such as metal. The region of the fixed substrate 47 facing the manifold 100 is an opening 48 that is completely removed in the thickness direction. Therefore, one surface of the manifold 100 is a compliance portion 49 sealed only by the sealing film 46 having flexibility.

[0030] On the other hand, on the side of the pressure chamber substrate 10 opposite to the nozzle plate 20, i.e., on the surface on the -Z direction side, a vibration plate 50 and a piezoelectric element 300 that flexes and deforms the vibration plate 50 to cause a pressure change in the ink in the pressure chamber 12 are laminated, as will be described later in detail. In other words, the vibration plate 50 is provided in the +Z direction of the Z axis direction with respect to the piezoelectric element 300, and the pressure chamber substrate 10 is provided in the +Z direction of the Z axis direction with respect to the vibration plate 50. The Z axis direction is an example of the lamination direction, the +Z direction is an example of one of the lamination directions, and the -Z direction is an example of the other of the lamination directions. Note that FIG. 4 is a diagram for explaining the overall configuration of the liquid ejection head 510, and the configuration of the piezoelectric element 300 is shown in a simplified manner.

[0031] A protective substrate 30 having approximately the same size as the pressure chamber substrate 10 is further bonded to the surface of the pressure chamber substrate 10 on the -Z direction side by an adhesive or the like. The protective substrate 30 has a holding portion 31 which is a space for protecting the piezoelectric elements 300. The holding portion 31 is provided independently for each row of the piezoelectric elements 300 arranged side by side in the Y axis direction, and two holding portions 31 are formed side by side in the X axis direction. In addition, the protective substrate 30 is provided with a through hole 32 penetrating in the Z axis direction between the two holding portions 31 arranged side by side in the X axis direction.

[0032] In addition, a case member 40 is fixed onto the protective substrate 30. The case member 40 defines, together with the pressure chamber substrate 10, a manifold 100 that communicates with the multiple pressure chambers 12. The case member 40 has substantially the same shape as the above-mentioned communicating plate 15 when viewed in a plan view from the -Z direction, and is joined to the protective substrate 30 and also to the above-mentioned communicating plate 15.

[0033] Such a case member 40 has an accommodation section 41 on the protective substrate 30 side, which is a space deep enough to accommodate the pressure chamber substrate 10 and the protective substrate 30. This accommodation section 41 has an opening area larger than the surface of the protective substrate 30 that is joined to the pressure chamber substrate 10. Then, with the pressure chamber substrate 10 and the protective substrate 30 accommodated in the accommodation section 41, the opening surface of the accommodation section 41 on the nozzle plate 20 side is sealed by a communicating plate 15.

[0034] Additionally, third manifold portions 42 are defined on both outer sides of the accommodation portion 41 in the X-axis direction in the case member 40. The manifold 100 of this embodiment is configured by the first manifold portion 17 and the second manifold portion 18 provided in the communication plate 15, and the third manifold portion 42. The manifold 100 is provided continuously along the Y-axis direction, and the supply communication passages 19 that communicate between each pressure chamber 12 and the manifold 100 are arranged side by side in the Y-axis direction.

[0035] Moreover, the case member 40 is provided with a supply port 44 that communicates with the manifolds 100 and supplies ink to each manifold 100. Furthermore, the case member 40 is provided with a connection port 43 that communicates with the through hole 32 of the protection substrate 30 and through which the wiring substrate 120 is inserted.

[0036] In the liquid ejection head 510 of this embodiment, ink is taken in from the supply port 44 connected to the ink tank 550 via the tube 552, and the inside is filled with ink from the manifold 100 to the nozzles 21. Then, a voltage based on a drive signal is applied from the head circuit 121 to each of the piezoelectric elements 300 corresponding to the pressure chambers 12. This causes the vibration plate 50 to bend and deform together with the piezoelectric elements 300, increasing the pressure inside each pressure chamber 12, and ink droplets are ejected from each nozzle 21.

[0037] Hereinafter, a detailed description will be given of the configuration formed and laminated on the -Z direction side of the pressure chamber substrate 10, including the above-mentioned vibration plate 50 and piezoelectric element 300. The liquid ejection head 510 has, in addition to the vibration plate 50 and the piezoelectric element 300, an individual lead electrode 91, a common lead electrode 92, a measurement lead electrode 93, and a resistance wiring 401, as configurations formed and laminated on the -Z direction side of the pressure chamber substrate 10.

[0038] 4 to 6, the vibration plate 50 is composed of an elastic film 51 made of silicon oxide provided on the pressure chamber substrate 10 side, and an insulating film 52 made of zirconium oxide provided on the elastic film 51. The liquid flow paths of the pressure chambers 12, etc. are formed by anisotropically etching the pressure chamber substrate 10 from the surface on the +Z direction side, and the surface on the -Z direction side of the liquid flow paths of the pressure chambers 12, etc. is composed of the elastic film 51.

[0039] The configuration of the diaphragm 50 is not particularly limited. The diaphragm 50 may be composed of, for example, either the elastic film 51 or the insulating film 52, or may include other films in addition to the elastic film 51 and the insulating film 52. Examples of materials for the other films include silicon, silicon nitride, and the like.

[0040] The piezoelectric element 300 is an example of a piezoelectric actuator that generates a pressure change in the ink in the pressure chamber 12. This piezoelectric element 300 has a first electrode 60, a piezoelectric body 70, and a second electrode 80 that are sequentially stacked from the +Z direction side, which is the vibration plate 50 side, toward the -Z direction side. In other words, the piezoelectric element 300 includes the first electrode 60, the second electrode 80, and the piezoelectric body 70, and the piezoelectric body 70 is provided between the first electrode 60 and the second electrode 80 in the Z axis direction in which the first electrode 60, the second electrode 80, and the piezoelectric body 70 are stacked.

[0041] Both the first electrode 60 and the second electrode 80 are electrically connected to the wiring board 120, and a voltage corresponding to a drive signal supplied from a head circuit 121 mounted on the wiring board 120 is applied to the piezoelectric body 70. A drive voltage that varies depending on the amount of ink ejected is supplied to the first electrode 60, and a constant holding voltage is supplied to the second electrode 80 regardless of the amount of ink ejected. The amount of ink ejected is the amount of volume change required for the pressure chamber 12. This generates a potential difference between the first electrode 60 and the second electrode 80, and the piezoelectric body 70 is deformed. That is, when the piezoelectric element 300 is driven, the vibration plate 50 is deformed or vibrated, and the volume of the pressure chamber 12 is changed, so that pressure is applied to the ink contained in the pressure chamber 12, and the ink is ejected from the nozzle 21 through the nozzle communication passage 16.

[0042] In the piezoelectric element 300, a portion where piezoelectric strain occurs in the piezoelectric body 70 when a voltage is applied between the first electrode 60 and the second electrode 80 is referred to as an active portion 310. In contrast, a portion where piezoelectric strain does not occur in the piezoelectric body 70 is referred to as an inactive portion 320. In other words, in the piezoelectric element 300, a portion where the piezoelectric body 70 is sandwiched between the first electrode 60 and the second electrode 80 is the active portion 310, and a portion where the piezoelectric body 70 is not sandwiched between the first electrode 60 and the second electrode 80 is the inactive portion 320. Furthermore, when the piezoelectric element 300 is driven, a portion that actually displaces in the Z-axis direction is referred to as a flexible portion, and a portion that does not displace in the Z-axis direction is referred to as a non-flexible portion. That is, of the piezoelectric element 300, a portion that faces the pressure chamber 12 in the Z-axis direction is a flexible portion, and a portion outside the pressure chamber 12 is a non-flexible portion. The active section 310 is also called an active section, and the inactive section 320 is also called a non-active section.

[0043] In general, one of the electrodes of the active portions 310 is configured as an individual electrode independent for each active portion 310, and the other electrode is configured as a common electrode common to the multiple active portions 310. In this embodiment, the first electrode 60 constitutes the individual electrode, and the second electrode 80 constitutes the common electrode.

[0044] Specifically, the first electrode 60 is provided on the +Z direction side of the piezoelectric body 70 in the Z axis direction, and is separated for each pressure chamber 12 to form an independent individual electrode for each active section 310. That is, the first electrode 60 is provided individually for the multiple pressure chambers 12. The first electrode 60 is formed with a width narrower than the width of the pressure chamber 12 in the Y axis direction. That is, in the Y axis direction, the end of the first electrode 60 is located inside the region facing the pressure chamber 12.

[0045] Further, the +X-direction end 60a and the -X-direction end 60b of the first electrode 60 are each disposed outside the pressure chamber 12. For example, in the first pressure chamber row, as shown in Fig. 5, the end 60a of the first electrode 60 is disposed at a position on the +X-direction side of the end 12a of the pressure chamber 12 in the +X direction. The end 60b of the first electrode 60 is disposed at a position on the -X-direction side of the end 12b of the pressure chamber 12 in the -X direction.

[0046] The material of the first electrode 60 is not particularly limited, and may be, for example, a conductive material such as a metal such as platinum (Pt), iridium (Ir), gold (Au), or titanium (Ti), or a conductive metal oxide such as indium tin oxide (ITO). Alternatively, the first electrode 60 may be formed by laminating a plurality of materials such as platinum (Pt), iridium (Ir), gold (Au), or titanium (Ti). In this embodiment, the first electrode 60 is made of platinum (Pt).

[0047] 3, the piezoelectric body 70 has a predetermined length in the X-axis direction and is provided continuously along the Y-axis direction. That is, the piezoelectric body 70 is provided continuously with a predetermined thickness along the arrangement direction of the pressure chambers 12. The thickness of the piezoelectric body 70 is not particularly limited, but is formed to a thickness of about 1000 nanometers to 4000 nanometers.

[0048] 5, the length of the piezoelectric body 70 in the X-axis direction is longer than the length of the pressure chamber 12 in the X-axis direction, which is the longitudinal direction of the pressure chamber 12. Therefore, the piezoelectric body 70 extends to the outside of the pressure chamber 12 on both sides of the pressure chamber 12 in the X-axis direction. In this manner, the strength of the vibration plate 50 is improved by the piezoelectric body 70 extending to the outside of the pressure chamber 12 in the X-axis direction. Therefore, when the active portion 310 is driven to displace the piezoelectric element 300, the occurrence of cracks and the like in the vibration plate 50 and the piezoelectric element 300 can be suppressed.

[0049] 5, in the first pressure chamber row, the end 70a in the +X direction of the piezoelectric body 70 is located on the +X direction side, that is, outside the end 60a of the first electrode 60. In other words, the end 60a of the first electrode 60 is covered by the piezoelectric body 70. On the other hand, the end 70b in the -X direction of the piezoelectric body 70 is located on the +X direction side, that is, inside the end 60b of the first electrode 60, and the end 60b of the first electrode 60 is not covered by the piezoelectric body 70.

[0050] 3 and 6, the piezoelectric body 70 has grooves 71 that correspond to the partition walls 11 and are thinner than other regions. The grooves 71 in this embodiment are formed by completely removing the piezoelectric body 70 in the Z-axis direction. That is, the piezoelectric body 70 having a portion thinner than other regions includes the piezoelectric body 70 being completely removed in the Z-axis direction. Of course, the piezoelectric body 70 may be formed thinner on the bottom surface of the grooves 71 than other portions.

[0051] The length of the groove 71 in the Y-axis direction, i.e., the width of the groove 71, is equal to or greater than the width of the partition wall 11. In this embodiment, the width of the groove 71 is greater than the width of the partition wall 11.

[0052] Such groove portion 71 is formed to have a rectangular shape when viewed from the -Z direction side. Of course, the shape of groove portion 71 when viewed from the -Z direction side is not limited to a rectangular shape, and may be a polygonal shape having 5 or more sides, a circular shape, an elliptical shape, or the like.

[0053] By providing the groove portion 71 in the piezoelectric body 70, the rigidity of the portion of the vibration plate 50 facing the end portion of the pressure chamber 12 in the Y-axis direction, i.e., the arm portion of the vibration plate 50, is reduced, thereby allowing the piezoelectric element 300 to be displaced more effectively.

[0054] The piezoelectric body 70 may be a crystal film of a perovskite structure made of a ferroelectric ceramic material exhibiting an electromechanical conversion action formed on the first electrode 60, that is, a so-called perovskite crystal. The material of the piezoelectric body 70 may be, for example, a ferroelectric piezoelectric material such as lead zirconate titanate (PZT) or a material to which a metal oxide such as niobium oxide, nickel oxide, or magnesium oxide is added. Specifically, lead titanate (PbTiO3), lead zirconate titanate (Pb(Zr,Ti)O3), lead zirconate (PbZrO3), lead lanthanum titanate ((Pb,La),TiO3), lead lanthanum zirconate titanate ((Pb,La)(Zr,Ti)O3), or magnesium zirconium niobate titanate (Pb(Zr,Ti)(Mg,Nb)O3) may be used. In this embodiment, lead zirconate titanate (PZT) is used as the piezoelectric body 70.

[0055] Furthermore, the material of the piezoelectric body 70 is not limited to lead-based piezoelectric materials that contain lead, and lead-free piezoelectric materials that do not contain lead can also be used. Examples of lead-free piezoelectric materials include bismuth ferrate ((BiFeO3), abbreviated as "BFO"), barium titanate ((BaTiO3), abbreviated as "BT"), potassium sodium niobate ((K,Na)(NbO3), abbreviated as "KNN"), potassium sodium lithium niobate ((K,Na,Li)(NbO3)), potassium sodium lithium tantalate niobate ((K,Na,Li)(Nb,Ta)O3), bismuth potassium titanate ((Bi1 / 2K1 / 2)TiO3, abbreviated as "BKT"), bismuth sodium titanate ((Bi1 / 2Na1 / 2)TiO3, abbreviated as "BNT"), manganese, and the like. Examples of such oxides include bismuth phosphate (BiMnO3, abbreviated as "BM"), composite oxides containing bismuth, potassium, titanium, and iron and having a perovskite structure (x[(BixK1-x)TiO3]-(1-x)[BiFeO3], abbreviated as "BKT-BF"), composite oxides containing bismuth, iron, barium, and titanium and having a perovskite structure ((1-x)[BiFeO3]-x[BaTiO3], abbreviated as "BFO-BT"), and oxides to which metals such as manganese, cobalt, and chromium have been added ((1-x)[Bi(Fe1-yMy)O3]-x[BaTiO3] (M is Mn, Co, or Cr)).

[0056] As shown in FIG. 3, FIG. 5, and FIG. 6, the second electrode 80 is provided on the −Z direction side of the Z axis direction, which is the opposite side of the first electrode 60, with respect to the piezoelectric body 70, and constitutes a common electrode common to the multiple active parts 310. That is, the second electrode 80 is provided in common to the multiple pressure chambers 12. The second electrode 80 is provided continuously in the Y axis direction with a predetermined length in the X axis direction. This second electrode 80 is also provided on the inner surface of the groove portion 71, that is, on the side surface of the groove portion 71 of the piezoelectric body 70 and on the insulating film 52 which is the bottom surface of the groove portion 71. Note that, with respect to the inside of the groove portion 71, the second electrode 80 may be provided only on a part of the inner surface of the groove portion 71, and may not be provided over the entire inner surface of the groove portion 71.

[0057] 5, in the first pressure chamber row, the end 80a in the +X direction of the second electrode 80 is disposed on the +X direction side so as to be outside the end 60a of the first electrode 60 covered by the piezoelectric body 70. That is, the end 80a of the second electrode 80 is located on the +X direction side outside the end 12a of the pressure chamber 12 and on the +X direction side outside the end 60a of the first electrode 60. In this embodiment, the end 80a of the second electrode 80 substantially coincides with the end 70a of the piezoelectric body 70 in the X-axis direction. Therefore, the end of the active portion 310 in the +X direction, i.e., the boundary between the active portion 310 and the inactive portion 320, is defined by the end 60a of the first electrode 60.

[0058] On the other hand, the -X direction end 80b of the second electrode 80 is disposed on the -X direction side, which is outer than the -X direction end 12b of the pressure chamber 12, but is disposed on the +X direction side, which is inner than the end 70b of the piezoelectric body 70. As described above, the end 70b of the piezoelectric body 70 is located on the inside, which is the +X direction side, of the end 60b of the first electrode 60. Therefore, the end 80b of the second electrode 80 is located on the piezoelectric body 70, which is on the +X direction side of the end 60b of the first electrode 60. Therefore, on the -X direction side of the end 80b of the second electrode 80, there is a portion where the surface of the piezoelectric body 70 is exposed.

[0059] In this way, the end 80b of the second electrode 80 is positioned on the +X direction side of the end 70b of the piezoelectric body 70 and the end 60b of the first electrode 60, and therefore the -X direction end of the active portion 310, i.e., the boundary between the active portion 310 and the inactive portion 320, is defined by the end 80b of the second electrode 80.

[0060] The material of the second electrode 80 is not particularly limited, but similar to the first electrode 60, a conductive material such as metals such as platinum (Pt), iridium (Ir), gold (Au), and titanium (Ti), or a conductive metal oxide such as indium tin oxide abbreviated as ITO, is used. Alternatively, the second electrode 80 may be formed by laminating a plurality of materials such as platinum (Pt), iridium (Ir), gold (Au), and titanium (Ti). In this embodiment, iridium (Ir) is used as the second electrode 80.

[0061] Further, outside the end 80b of the second electrode 80, that is, on the further -X direction side of the end 80b of the second electrode 80, a wiring portion 85 is provided which is in the same layer as the second electrode 80 but is electrically discontinuous with the second electrode 80. The wiring portion 85 is formed over the first electrode 60 extending from the piezoelectric body 70 in the -X direction beyond the piezoelectric body 70 with a gap therebetween so as not to contact the end 80b of the second electrode 80. This wiring portion 85 is provided independently for each active portion 310. That is, a plurality of wiring portions 85 are arranged at predetermined intervals along the Y-axis direction. The wiring portion 85 may be formed in a layer different from the second electrode 80, but is preferably formed in the same layer as the second electrode 80. This simplifies the manufacturing process of the wiring portion 85 and reduces costs.

[0062] In addition, the first electrode 60 and the second electrode 80 constituting the piezoelectric element 300 are electrically connected to an individual lead electrode 91 and to a common lead electrode 92, which is a common electrode for driving, respectively. The individual lead electrode 91 is an example of a first wiring, and the common lead electrode 92 is an example of a second wiring. A flexible wiring board 120 is electrically connected to the ends of the individual lead electrode 91 and the common lead electrode 92 opposite to the ends connected to the piezoelectric element 300. The wiring board 120 has a plurality of wirings formed thereon for connecting to the control unit 580 and a power supply circuit (not shown). In this embodiment, the wiring board 120 is formed of, for example, an FPC (Flexible Printed Circuit). Note that, instead of the FPC, any flexible board such as an FFC (Flexible Flat Cable) may be used.

[0063] In this embodiment, the individual lead electrodes 91 and the common lead electrode 92 are extended so as to be exposed in through holes 32 formed in the protective substrate 30, and are electrically connected to the wiring substrate 120 within the through holes 32. A head circuit 121 having a switching element for driving the piezoelectric element 300 is mounted on the wiring substrate 120.

[0064] In this embodiment, the individual lead electrode 91 and the common lead electrode 92 are made of the same layer, but are formed so as to be electrically discontinuous. This simplifies the manufacturing process and reduces costs compared to when the individual lead electrode 91 and the common lead electrode 92 are formed separately. Of course, the individual lead electrode 91 and the common lead electrode 92 may be formed in different layers.

[0065] The material of the individual lead electrode 91 and the common lead electrode 92 is not particularly limited as long as it is a material having electrical conductivity, and for example, gold (Au), copper (Cu), titanium (Ti), tungsten (W), nickel (Ni), chromium (Cr), platinum (Pt), aluminum (Al), etc. can be used. In this embodiment, gold (Au) is used for the individual lead electrode 91 and the common lead electrode 92. In addition, the individual lead electrode 91 and the common lead electrode 92 may have an adhesion layer that improves adhesion with the first electrode 60, the second electrode 80, and the diaphragm 50.

[0066] The individual lead electrodes 91 are provided for each active portion 310, that is, for each first electrode 60. As shown in Fig. 5, for example, in the first pressure chamber row, the individual lead electrodes 91 are connected via wiring portions 85 to the vicinity of the ends 60b of the first electrodes 60 provided on the outer side of the piezoelectric body 70, and are drawn out in the -X direction onto the pressure chamber substrate 10, actually onto the diaphragm 50.

[0067] On the other hand, as shown in Fig. 3, for example, in the first pressure chamber row, the common lead electrode 92 is drawn in the -X direction from above the second electrode 80 constituting the common electrode on the piezoelectric body 70 to above the vibration plate 50 at both ends in the Y axis direction. The common lead electrode 92 also has an extension portion 92a and an extension portion 92b. As shown in Figs. 3 and 5, for example, in the first pressure chamber row, the extension portion 92a is provided extending along the Y axis direction in a region corresponding to the end portion 12a of the pressure chamber 12, and the extension portion 92b is provided extending along the Y axis direction in a region corresponding to the end portion 12b of the pressure chamber 12. These extension portions 92a and 92b are provided continuously in the Y axis direction for the multiple active portions 310.

[0068] Moreover, the extension portion 92a and the extension portion 92b extend in the X-axis direction from the inside of the pressure chamber 12 to the outside of the pressure chamber 12. In this embodiment, the active portion 310 of the piezoelectric element 300 extends to the outside of the pressure chamber 12 at both ends of the pressure chamber 12 in the X-axis direction, and the extension portion 92a and the extension portion 92b extend on this active portion 310 to the outside of the pressure chamber 12.

[0069] As shown in FIG. 5, a resistive wiring 401 (first resistive wiring) is provided on the surface of the vibration plate 50 on the -Z direction side. The resistive wiring 401 is an example of a temperature detection unit for detecting the temperature of the pressure chamber 12. The temperature detection unit of this embodiment utilizes the characteristic that the electric resistance value of metals, semiconductors, etc. changes with temperature. The material of the resistive wiring 401 is not particularly limited as long as the electric resistance value has temperature dependency, and for example, gold (Au), platinum (Pt), iridium (Ir), aluminum (Al), copper (Cu), titanium (Ti), tungsten (W), nickel (Ni), chromium (Cr), etc. can be used. Among these, platinum (Pt) can be suitably adopted as the material of the resistive wiring 401 from the viewpoint of large resistance value change with temperature and high stability and accuracy. The electric resistance value is an example of a measured value of the temperature detection unit to be measured. In this embodiment, the resistive wiring 401 is formed in the same layer as the first electrode 60, and is laminated on the surface of the diaphragm 50 in the -Z direction so as to be electrically discontinuous with the first electrode 60. Therefore, the material of the resistive wiring 401 is platinum (Pt), the same as the first electrode 60. This simplifies the manufacturing process and reduces costs compared to when the resistive wiring 401 is formed separately from the first electrode 60. Of course, the resistive wiring 401 may be formed in a layer different from the first electrode 60.

[0070] 3, the resistive wiring 401 is continuous, and one end of the resistive wiring 401 on the +X direction side in the X-axis direction is connected to the measurement lead electrode 93a, and the other end of the resistive wiring 401 on the -X direction side in the X-axis direction is connected to the measurement lead electrode 93b. This electrically connects the resistive wiring 401 to the wiring board 120, and the control unit 580 can measure the electrical resistance value of the resistive wiring 401. The measurement lead electrodes 93 including the measurement lead electrodes 93a and 93b are an example of a connection part of the resistive wiring 401 with the wiring board 120. In this embodiment, the resistive wiring 401 is covered with the piezoelectric body 70, and is located between the vibration plate 50 and the piezoelectric body 70 in the Z-axis direction.

[0071] The resistance wiring 401 includes a first pressure chamber column side meandering pattern on the +X direction side in the X axis direction, and a second pressure chamber column side meandering pattern on the -X direction side in the X axis direction. The first pressure chamber column side meandering pattern meanders along the Y axis direction at a position overlapping with the supply communication passage 19 communicating with each pressure chamber 12 constituting the first pressure chamber column when viewed from the -Z direction. The second pressure chamber column side meandering pattern meanders along the Y axis direction at a position overlapping with the supply communication passage 19 communicating with each pressure chamber 12 constituting the second pressure chamber column when viewed from the -Z direction. That is, the resistance wiring 401 includes a first pressure chamber column side meandering pattern corresponding to the first pressure chamber column formed by the multiple pressure chambers 12, and a second pressure chamber column side meandering pattern corresponding to the second pressure chamber column formed by the multiple pressure chambers 12. 4 and 5, the distance in the Z-axis direction between the end of the pressure chamber 12 on the -Z direction side and the resistance wiring 401 is shorter than the dimension in the Z-axis direction of the pressure chamber 12. Also, for example, in the first pressure chamber row, the maximum distance in the X-axis direction between the end 12a of the pressure chamber 12 in the +X direction and the resistance wiring 401 is shorter than the dimension in the X-axis direction of the pressure chamber 12. For this reason, the electrical resistance value of the resistive wiring 401 is likely to change in response to a change in temperature of the pressure chamber 12 .

[0072] In this embodiment, the measurement lead electrodes 93 including the measurement lead electrodes 93a and 93b are made of the same layer as the individual lead electrodes 91 and the common lead electrode 92, but are formed so as to be electrically discontinuous. This simplifies the manufacturing process and reduces costs compared to when the measurement lead electrodes 93 are formed separately from the individual lead electrodes 91 and the common lead electrode 92. Of course, the measurement lead electrodes 93 may be formed in a layer different from the individual lead electrodes 91 and the common lead electrode 92.

[0073] The material of the measurement lead electrode 93 is not particularly limited as long as it is a material having electrical conductivity, and for example, gold (Au), copper (Cu), titanium (Ti), tungsten (W), nickel (Ni), chromium (Cr), platinum (Pt), aluminum (Al), etc. can be used. In this embodiment, gold (Au) is used for the measurement lead electrode 93. Therefore, the material of the measurement lead electrode 93 is the same as that of the individual lead electrode 91 and the common lead electrode 92. In addition, the measurement lead electrode 93 may have an adhesion layer that improves adhesion with the resistance wiring 401 and the diaphragm 50.

[0074] In this embodiment, the measurement lead electrode 93 is extended so as to be exposed in the through hole 32 formed in the protection substrate 30, and is electrically connected to the wiring substrate 120 in this through hole 32. This allows the control unit 580 to acquire the electrical resistance value of the resistance wiring 401 via the wiring substrate 120. In this embodiment, the control unit 580 stores in advance the correspondence between the electrical resistance value of the resistance wiring 401 and the temperature. Then, when driving the piezoelectric element 300, the control unit 580 measures the electrical resistance value of the resistance wiring 401, and detects the temperature of the pressure chamber 12 based on the correspondence between the electrical resistance value of the resistance wiring 401 and the temperature.

[0075] For example, if the temperature detection unit is provided outside the liquid ejection head 510, the difference between the temperature measured by the temperature detection unit and the temperature in the pressure chamber 12 may be larger than the difference between the temperature in the liquid ejection head 510 and the temperature in the pressure chamber 12. In this case, the liquid ejection device 500 may not be able to control the ejection of the liquid ejection head 510 to suit the temperature of the ink in the pressure chamber 12. In this embodiment, the resistance wiring 401 is provided by laminating it on the vibration plate 50, which is a component of the liquid ejection head 510. That is, the resistance wiring 401 is provided inside the liquid ejection head 510. According to this, since the liquid ejection head 510 has the resistance wiring 401, the difference between the temperature detected based on the measured electric resistance value of the resistance wiring 401 and the temperature in the pressure chamber 12 can be made smaller than when the temperature of the external environment of the liquid ejection head 510 is measured. Also, according to this, the liquid ejection device 500 can easily control the ejection of the liquid ejection head 510 to suit the temperature of the ink in the pressure chamber 12.

[0076] As described above, according to the liquid ejection head 510 according to the first embodiment and the liquid ejection apparatus 500 according to the first embodiment, the following effects can be obtained.

[0077] The liquid ejection head 510 includes a first electrode 60, a second electrode 80, and a piezoelectric body 70, and has a piezoelectric element 300 in which the first electrode 60, the second electrode 80, and the piezoelectric body 70 are stacked in the Z-axis direction, with the piezoelectric body 70 being provided between the first electrode 60 and the second electrode 80, a vibration plate 50 provided on the +Z direction side of the Z-axis direction with respect to the piezoelectric element 300, and a pressure chamber substrate 10 provided on the +Z direction side of the vibration plate 50 in the Z-axis direction, the pressure chamber substrate 10 having a plurality of pressure chambers 12 whose volume changes due to deformation of the vibration plate 50 caused by driving of the piezoelectric element 300, a wiring board 120, individual lead electrodes 91 electrically connecting the wiring board 120 and the first electrode 60, a common lead electrode 92 electrically connecting the wiring board 120 and the second electrode 80, and a resistance wiring 401 electrically connected to the wiring board 120 and for detecting the temperature of the pressure chambers 12. According to this, since the liquid ejection head 510 has the resistive wiring 401, the difference between the temperature detected based on the measured value of the resistive wiring 401 and the temperature inside the pressure chamber 12 can be made smaller compared to the case where the temperature of the external environment of the liquid ejection head 510 is measured.

[0078] The resistance wiring 401 is formed from the same material as the first electrode 60. This makes it easy to form the resistance wiring 401 in the same process as the first electrode 60.

[0079] The first electrodes 60 are provided individually for the multiple pressure chambers 12 aligned in the Y-axis direction, and the second electrode 80 is provided commonly to the multiple pressure chambers 12, with the first electrode 60 provided on the +Z side of the piezoelectric body 70 in the Z-axis direction, and the second electrode 80 provided on the -Z side of the piezoelectric body 70 in the Z-axis direction. This makes it easy to drive the piezoelectric element 300 in accordance with the required amount of ink ejection.

[0080] The wiring board 120 includes a head circuit 121, which applies a drive voltage that changes in accordance with the amount of ink ejected to the first electrode 60 via an individual lead electrode 91, and is capable of applying a constant holding voltage, regardless of the amount of ink ejected, to the second electrode 80 via a common lead electrode 92. This makes it easy to drive the piezoelectric element 300 in accordance with the required amount of ink ejected.

[0081] The individual lead electrode 91 is provided between the common lead electrode 92 and the measurement lead electrode 93 in the Y-axis direction. This allows the first electrode 60, the second electrode 80, and the resistance wiring 401 to be connected to the wiring board 120 efficiently.

[0082] The liquid ejection device 500 includes a liquid ejection head 510 and a control unit 580 that controls the ink ejection operation from the liquid ejection head 510. This makes it possible to easily realize a configuration that is capable of controlling the ejection operation of the liquid ejection head 510.

[0083] 2. Embodiment 2 Next, a description will be given of the resistance wiring 451 provided in the liquid ejection head 510 according to the second embodiment of the present disclosure. Note that the same reference numerals will be used to designate parts common to the liquid ejection head 510 according to the first embodiment, and description thereof will be omitted.

[0084] The resistive wiring 401 in the first embodiment is laminated on the surface of the vibration plate 50 in the -Z direction so as to be in the same layer as the first electrode 60 and electrically discontinuous with the first electrode 60. In contrast to this, the resistive wiring 451 in the present embodiment is provided on the surface of the piezoelectric body 70 in the -Z direction as shown in FIG. 7. The resistive wiring 451 is an example of a temperature detection unit for detecting the temperature of the pressure chamber 12. The material of the resistive wiring 451 is not particularly limited as long as the material has a temperature-dependent electrical resistance value, and for example, gold (Au), platinum (Pt), iridium (Ir), aluminum (Al), copper (Cu), titanium (Ti), tungsten (W), nickel (Ni), chromium (Cr), etc. can be used. In the present embodiment, the resistive wiring 451 is laminated on the surface of the piezoelectric body 70 in the -Z direction so as to be in the same layer as the second electrode 80 and electrically discontinuous with the second electrode 80. Therefore, the material of the resistance wiring 451 is iridium (Ir), the same as that of the second electrode 80. This simplifies the manufacturing process and reduces costs compared to the case where the resistance wiring 451 is formed separately from the second electrode 80. Of course, the resistance wiring 451 may be formed in a layer different from that of the second electrode 80.

[0085] As described above, according to the liquid ejection head 510 of the second embodiment, the resistance wiring 451 is formed from the same material as the second electrode 80, and therefore the resistance wiring 451 can be easily formed in the same process as the second electrode 80.

[0086] 3. Embodiment 3 Next, a description will be given of a resistance wiring 461 provided in a liquid ejection head 510 according to a third embodiment of the present disclosure. Note that the same reference numerals will be used to designate parts common to the liquid ejection head 510 according to the first embodiment, and description thereof will be omitted.

[0087] The resistive wiring 401 in the first embodiment is formed in the same layer as the first electrode 60, and is laminated on the surface of the vibration plate 50 in the -Z direction so as to be electrically discontinuous with the first electrode 60. In contrast, the resistive wiring 461 in the present embodiment is provided on the surface of the piezoelectric body 70 in the -Z direction, as shown in FIG. 8. The resistive wiring 461 is an example of a temperature detection unit for detecting the temperature of the pressure chamber 12. The material of the resistive wiring 461 is not particularly limited as long as it is a material whose electrical resistance value has temperature dependency, and for example, gold (Au), platinum (Pt), iridium (Ir), aluminum (Al), copper (Cu), titanium (Ti), tungsten (W), nickel (Ni), chromium (Cr), etc. can be used.

[0088] In this embodiment, the resistive wiring 461 is formed on the same layer as the measurement lead electrode 93 including the measurement lead electrode 93a and the measurement lead electrode 93b, and is laminated on the surface of the piezoelectric body 70 in the -Z direction so as to be electrically continuous with the measurement lead electrode 93. That is, the resistive wiring 461 is the same wiring as the measurement lead electrode 93. Therefore, the resistive wiring 461 in this embodiment is formed from the same layer as the individual lead electrode 91 and the common lead electrode 92, but is formed so as to be electrically discontinuous. Therefore, the material of the resistive wiring 461 is gold (Au), which is the same material as the individual lead electrode 91 and the common lead electrode 92. This simplifies the manufacturing process and reduces costs compared to the case where the resistive wiring 461 is formed separately from the individual lead electrode 91 and the common lead electrode 92. Of course, the resistive wiring 461 may be formed on a layer different from the individual lead electrode 91, the common lead electrode 92, and the measurement lead electrode 93.

[0089] As described above, according to the liquid ejection head 510 of embodiment 3, the resistance wiring 461 is formed from the same material as either the individual lead electrode 91 or the common lead electrode 92, so that the resistance wiring 461 is easily formed in the same process as either the individual lead electrode 91 or the common lead electrode 92.

[0090] 4. Embodiment 4 Next, a description will be given of the resistance wiring provided in the liquid ejection head 510 according to the fourth embodiment of the present disclosure. Note that the same reference numerals will be used to designate parts common to the liquid ejection head 510 according to the first embodiment, and description thereof will be omitted.

[0091] The resistance wiring 401 of the first embodiment includes a first pressure chamber row side meandering pattern corresponding to the first pressure chamber row formed by the multiple pressure chambers 12, and a second pressure chamber row side meandering pattern corresponding to the second pressure chamber row formed by the multiple pressure chambers 12. That is, the liquid ejection head 510 of the first embodiment includes one resistance wiring 401 corresponding to the first pressure chamber row and the second pressure chamber row. In contrast, the liquid ejection head 510 of the present embodiment may include multiple temperature detection units provided corresponding to multiple pressure chamber groups formed by the multiple pressure chambers 12, as shown in Figs. 9 to 11. In this way, the liquid ejection head 510 can detect the temperatures of the multiple pressure chambers 12 divided into multiple groups.

[0092] 9, the pressure chamber group formed by the multiple pressure chambers 12 located on the -Y side of the center of the first pressure chamber row in the Y axis direction will be referred to as a first pressure chamber group G1, the pressure chamber group formed by the multiple pressure chambers 12 located on the +Y side of the center of the first pressure chamber row in the Y axis direction will be referred to as a second pressure chamber group G2, the pressure chamber group formed by the multiple pressure chambers 12 located on the -Y side of the center of the second pressure chamber row in the Y axis direction will be referred to as a third pressure chamber group G3, and the pressure chamber group formed by the multiple pressure chambers 12 located on the +Y side of the center of the second pressure chamber row in the Y axis direction will be referred to as a fourth pressure chamber group G4. Note that the -Y direction is an example of one side of the first direction, and the +Y direction is an example of the other side of the first direction.

[0093] 9, the liquid ejection head 510 may include a resistive wiring 402 (second resistive wiring) having a meandering pattern that meanders along the Y-axis direction at a position overlapping with the supply communication passage 19 that communicates with each pressure chamber 12 constituting the first pressure chamber row when viewed from the -Z direction, and a resistive wiring 403 (third resistive wiring) having a meandering pattern that meanders along the Y-axis direction at a position overlapping with the supply communication passage 19 that communicates with each pressure chamber 12 constituting the second pressure chamber row when viewed from the -Z direction. The resistive wiring 402 and the resistive wiring 403 are examples of a temperature detection unit for detecting the temperature of the pressure chamber 12. The measurement lead electrode 93 may include a measurement lead electrode 93a, a measurement lead electrode 93b, a measurement lead electrode 93c, and a measurement lead electrode 93d.

[0094] The resistive wiring 402 is continuous, with one end of the resistive wiring 402 connected to the measurement lead electrode 93a, and the other end of the resistive wiring 402 connected to the measurement lead electrode 93c. The resistive wiring 403 is continuous, with one end of the resistive wiring 403 connected to the measurement lead electrode 93b, and the other end of the resistive wiring 403 connected to the measurement lead electrode 93d. This electrically connects the resistive wiring 402 to the wiring board 120, and the control unit 580 becomes able to measure the electrical resistance value of the resistive wiring 402. The resistive wiring 403 is also electrically connected to the wiring board 120, and the control unit 580 becomes able to measure the electrical resistance value of the resistive wiring 403.

[0095] In this case, the multiple pressure chamber groups include a first pressure chamber row and a second pressure chamber row. As a result, when the temperature of ink in the pressure chambers 12 constituting the first pressure chamber row and the temperature of ink in the pressure chambers 12 constituting the second pressure chamber row are different, the liquid ejection head 510 of this embodiment can drive the piezoelectric elements 300 corresponding to the temperature of ink in the pressure chambers 12 constituting each pressure chamber row. Also, as a result, the liquid ejection device 500 can more easily perform ejection control of the liquid ejection head 510 suited to the temperature of ink in the pressure chambers 12.

[0096] 10, the liquid ejection head 510 may include a resistance wiring 404 (fourth resistance wiring) having a meandering pattern that meanders along the Y-axis direction at a position overlapping with the supply communication passage 19 communicating with each pressure chamber 12 constituting the first pressure chamber group G1, and a meandering pattern that meanders along the Y-axis direction at a position overlapping with the supply communication passage 19 communicating with each pressure chamber 12 constituting the third pressure chamber group G3, as viewed from the -Z direction, and a resistance wiring 405 (fifth resistance wiring) having a meandering pattern that meanders along the Y-axis direction at a position overlapping with the supply communication passage 19 communicating with each pressure chamber 12 constituting the second pressure chamber group G2, and a meandering pattern that meanders along the Y-axis direction at a position overlapping with the supply communication passage 19 communicating with each pressure chamber 12 constituting the fourth pressure chamber group G4, as viewed from the -Z direction. The resistance wiring 404 and the resistance wiring 405 are examples of temperature detection units for detecting the temperature of the pressure chambers 12. Moreover, the measurement lead electrode 93 may include a measurement lead electrode 93a, a measurement lead electrode 93b, a measurement lead electrode 93c, and a measurement lead electrode 93d.

[0097] The resistive wiring 404 is continuous, with one end of the resistive wiring 404 connected to the measurement lead electrode 93a, and the other end of the resistive wiring 404 connected to the measurement lead electrode 93b. The resistive wiring 405 is continuous, with one end of the resistive wiring 405 connected to the measurement lead electrode 93c, and the other end of the resistive wiring 405 connected to the measurement lead electrode 93d. This electrically connects the resistive wiring 404 to the wiring board 120, and the control unit 580 becomes able to measure the electrical resistance value of the resistive wiring 404. The resistive wiring 405 is also electrically connected to the wiring board 120, and the control unit 580 becomes able to measure the electrical resistance value of the resistive wiring 405.

[0098] In this case, the multiple pressure chamber groups include a first pressure chamber group G1 and a second pressure chamber group G2. Alternatively, the multiple pressure chamber groups include a third pressure chamber group G3 and a fourth pressure chamber group G4. With this, when the temperature of ink in the pressure chambers 12 constituting the pressure chamber group on one side of the pressure chamber row is different from the temperature of ink in the pressure chambers 12 constituting the pressure chamber group on the other side of the pressure chamber row, the liquid ejection head 510 of this embodiment can drive the piezoelectric element 300 corresponding to the temperature of ink in the pressure chambers 12 constituting each pressure chamber group. Also, with this, the liquid ejection device 500 can more easily perform ejection control of the liquid ejection head 510 suited to the temperature of ink in the pressure chambers 12.

[0099] 11, the liquid ejection head 510 may include a resistance wiring 406 (sixth resistance wiring) having a serpentine pattern that meanders along the Y-axis direction at a position overlapping with the supply communication passages 19 communicating with each of the pressure chambers 12 constituting the first pressure chamber group G1 when viewed from the -Z direction, a resistance wiring 407 (seventh resistance wiring) having a serpentine pattern that meanders along the Y-axis direction at a position overlapping with the supply communication passages 19 communicating with each of the pressure chambers 12 constituting the second pressure chamber group G2 when viewed from the -Z direction, a resistance wiring 408 (eighth resistance wiring) having a serpentine pattern that meanders along the Y-axis direction at a position overlapping with the supply communication passages 19 communicating with each of the pressure chambers 12 constituting the third pressure chamber group G3, and a resistance wiring 409 (ninth resistance wiring) having a serpentine pattern that meanders along the Y-axis direction at a position overlapping with the supply communication passages 19 communicating with each of the pressure chambers 12 constituting the fourth pressure chamber group G4 when viewed from the -Z direction. The resistive wiring 406, the resistive wiring 407, the resistive wiring 408, and the resistive wiring 409 are examples of a temperature detection unit for detecting the temperature of the pressure chamber 12. The measurement lead electrode 93 may include a measurement lead electrode 93a, a measurement lead electrode 93b, a measurement lead electrode 93c, a measurement lead electrode 93d, a measurement lead electrode 93e, a measurement lead electrode 93f, a measurement lead electrode 93g, and a measurement lead electrode 93h.

[0100] The resistive wiring 406 is continuous, one end of the resistive wiring 406 is connected to the measurement lead electrode 93e, and the other end of the resistive wiring 406 is connected to the measurement lead electrode 93a. The resistive wiring 407 is continuous, one end of the resistive wiring 407 is connected to the measurement lead electrode 93c, and the other end of the resistive wiring 407 is connected to the measurement lead electrode 93g. The resistive wiring 408 is continuous, one end of the resistive wiring 408 is connected to the measurement lead electrode 93f, and the other end of the resistive wiring 408 is connected to the measurement lead electrode 93b. The resistive wiring 409 is continuous, one end of the resistive wiring 409 is connected to the measurement lead electrode 93d, and the other end of the resistive wiring 409 is connected to the measurement lead electrode 93h. As a result, the resistive wiring 406 is connected to the wiring board 120, and the control unit 580 can measure the electrical resistance value of the resistive wiring 406. Furthermore, resistance wiring 407 is connected to wiring board 120, and control unit 580 is able to measure the electrical resistance value of resistance wiring 407. Furthermore, resistance wiring 408 is connected to wiring board 120, and control unit 580 is able to measure the electrical resistance value of resistance wiring 408. Furthermore, resistance wiring 409 is connected to wiring board 120, and control unit 580 is able to measure the electrical resistance value of resistance wiring 409.

[0101] In this case, the multiple pressure chamber groups include a first pressure chamber group G1, a second pressure chamber group G2, a third pressure chamber group G3, and a fourth pressure chamber group G4. With this, the liquid ejection head 510 of this embodiment can drive the piezoelectric element 300 corresponding to the temperature of ink in the pressure chambers 12 constituting each pressure chamber group when, for example, the temperature of ink in the pressure chambers 12 constituting the first pressure chamber group G1, the temperature of ink in the pressure chambers 12 constituting the third pressure chamber group G3, the temperature of ink in the pressure chambers 12 constituting the second pressure chamber group G2, and the temperature of ink in the pressure chambers 12 constituting the fourth pressure chamber group G4 are different. Also, with this, the liquid ejection device 500 can more easily perform ejection control of the liquid ejection head 510 suitable for the temperature of ink in the pressure chambers 12.

[0102] 5. Embodiment 5 Next, a description will be given of a measurement lead electrode 93 and a resistance wiring 410 provided in a liquid ejection head 510 according to a fifth embodiment of the present disclosure. Note that the same reference numerals are used to designate parts common to the liquid ejection head 510 according to the first embodiment, and description thereof will be omitted.

[0103] The measurement lead electrode 93 in the first embodiment includes the measurement lead electrode 93a and the measurement lead electrode 93b, and one end of the resistance wiring 401 is connected to the measurement lead electrode 93a and the other end of the resistance wiring 401 is connected to the measurement lead electrode 93b. In contrast, as shown in Fig. 12, the measurement lead electrode 93 in this embodiment includes the measurement lead electrode 93i and the measurement lead electrode 93j. The measurement lead electrode 93 including the measurement lead electrode 93i and the measurement lead electrode 93j is an example of a connection portion of the resistance wiring 410 with the wiring board 120.

[0104] The liquid ejection head 510 of this embodiment also has a resistive wiring 410. The resistive wiring 410 is an example of a temperature detection unit for detecting the temperature of the pressure chamber 12. The resistive wiring 410 is continuous, and one end of the resistive wiring 410 on the +X side in the X-axis direction is connected to the measurement lead electrode 93i, and the other end of the resistive wiring 410 on the -X side in the X-axis direction is connected to the measurement lead electrode 93j. This electrically connects the resistive wiring 410 to the wiring board 120, and the control unit 580 becomes able to measure the electrical resistance value of the resistive wiring 410.

[0105] In this embodiment, the measurement lead electrode 93 is provided between the individual lead electrode 91 and the common lead electrode 92 in the Y-axis direction. This allows the first electrode 60, the second electrode 80, and the resistance wiring 410 to be connected to the wiring board 120 efficiently.

[0106] Furthermore, as in this embodiment, the measurement lead electrode 93 may be provided between the individual lead electrode 91 and the common lead electrode 92 in the Y-axis direction, while multiple temperature detection units corresponding to multiple pressure chamber groups may be provided as in embodiments 2 to 4.

[0107] The liquid ejection head 510 and the liquid ejection device 500 according to the above embodiment of the present invention are basically configured as described above, but it is of course possible to modify or omit a portion of the configuration without departing from the gist of the present invention. Furthermore, the above embodiment and other embodiments described below can be combined with each other within a range that does not cause technical contradiction. Other embodiments will be described below.

[0108] In each of the above embodiments, the control unit 580 may not have the function of measuring the electrical resistance value of the resistive wiring 401 and detecting the temperature of the pressure chamber 12. The liquid ejection head 510 may have the function of measuring the electrical resistance value of the resistive wiring 401 and detecting the temperature of the pressure chamber 12. In this case, for example, the liquid ejection head 510 may include a temperature detection circuit having a memory unit SA that stores in advance the correspondence between the measured value in the temperature detection unit and the temperature, a measurement value acquisition unit MA that measures the measured value in the temperature detection unit, and a temperature acquisition unit TA that acquires the temperature when the piezoelectric element 300 is driven based on the correspondence stored in the memory unit SA and the measured value acquired by the measurement value acquisition unit MA. The measured value in the temperature detection unit may be an electrical resistance value, and in this case, the measurement value acquisition unit MA may be a resistance acquisition unit MA. Alternatively, the liquid ejection head 510 may include the memory unit SA, the measurement value acquisition unit MA, and the temperature acquisition unit TA in the head circuit 121. Then, the liquid ejection head 510 may measure the electrical resistance value of the resistance wiring 401 when driving the piezoelectric element 300, and detect the temperature of the pressure chamber 12 based on the correspondence between the electrical resistance value of the resistance wiring 401 and the temperature.

[0109] In each of the above embodiments, there is no particular limitation on the method for measuring the electrical resistance value of the resistive wiring 401. For example, a known two-terminal measurement method or four-terminal measurement method can be used.

[0110] In each of the above embodiments, the resistance wiring may not be provided corresponding to all of the pressure chambers 12. For example, in embodiment 1, the resistance wiring 401 may be provided corresponding to the multiple pressure chambers 12 that make up the first pressure chamber row, and may not be provided corresponding to the pressure chambers 12 that make up the second pressure chamber row. Alternatively, the resistance wiring 401 may be provided corresponding to some of the multiple pressure chambers 12 that make up the first pressure chamber row, and some of the pressure chambers 12 that make up the second pressure chamber row.

[0111] In each of the above embodiments, the meandering pattern of the resistance wiring does not have to meander along the Y-axis direction at a position overlapping with the supply communication passage 19 communicating with the corresponding pressure chamber 12 when viewed from the -Z direction. For example, in embodiment 1, the first pressure chamber row side meandering pattern of the resistance wiring 401 may meander along the X-axis direction at a position overlapping with the supply communication passage 19 communicating with each pressure chamber 12 constituting the first pressure chamber row when viewed from the -Z direction.

[0112] In each of the above-described embodiments, the resistance wiring does not have to be meandering as long as it is provided at a position that overlaps with the supply communication passage 19 that communicates with the corresponding pressure chamber 12 when viewed from the -Z direction.

[0113] In each of the above embodiments, the resistance wiring may be provided so as to pass through a position overlapping with the corresponding pressure chamber 12 when viewed from the -Z direction. For example, in embodiment 1, the resistance wiring 401 may be provided so as to pass through a position that is on the outer side in the Y-axis direction with respect to the first electrode 60 when viewed from the -Z direction and that overlaps with the pressure chamber 12.

[0114] In each of the above embodiments, the first electrode 60 may be a common electrode, and the second electrode 80 may be an individual electrode. In this case, the first electrode 60 is provided on the +Z side of the piezoelectric body 70 in the Z-axis direction, and is provided in common to the multiple pressure chambers 12. The second electrode 80 is provided on the -Z side of the piezoelectric body 70 in the Z-axis direction, and is provided individually for the multiple pressure chambers 12. In this case, the first electrode 60 is connected to a common lead electrode 92, and the second electrode 80 is connected to an individual lead electrode 91.

[0115] In each of the above embodiments, the temperature detector may not be a resistive wire, and may be, for example, a thermocouple, as long as it can detect the temperature of the pressure chamber 12 based on the measured value in the temperature detector. For example, in the first embodiment, when the resistive wire 401 is replaced with a thermocouple, a temperature measurement junction where one ends of two kinds of metal wires constituting the thermocouple are connected to each other may be disposed at a position overlapping with the supply communication path 19 communicating with the multiple pressure chambers 12 constituting the first pressure chamber row and the second pressure chamber row, as viewed from the -Z direction. Then, by electrically connecting the other end of one metal wire to the measurement lead electrode 93a and electrically connecting the other end of the other metal wire to the measurement lead electrode 93b, the control unit 580 can measure the thermoelectromotive force of the thermocouple, which is the potential difference between the other end of one metal wire and the other end of the other metal wire. The control unit 580 may measure the thermoelectromotive force of the thermocouple when driving the piezoelectric element 300, and detect the temperature of the pressure chamber 12 based on the thermoelectromotive force of the thermocouple and the temperature near the wiring board 120 detected by a temperature sensor separately provided on the wiring board 120. In this case, the two types of metal wiring constituting the thermocouple may be laminated in the same layer as any one of the first electrode 60, the second electrode 80, the individual lead electrode 91, and the common lead electrode 92. For example, as shown in FIG. 13, in the first embodiment, one metal wiring 471a of the two types of metal wiring constituting the thermocouple 471 is laminated on the surface of the piezoelectric body 70 in the -Z direction so as to be in the same layer as the second electrode 80 and electrically discontinuous with the second electrode 80. The other metal wiring 471b constituting the thermocouple 471 may be laminated on the surface of the metal wiring 471a in the -Z direction so as to be in the same layer as the individual lead electrode 91 and the common lead electrode 92 and to be electrically discontinuous with the individual lead electrode 91 and the common lead electrode 92. Furthermore, the material of the second electrode 80 may be platinum (Pt), the material of the metal wiring 471a may be platinum (Pt), and the material of the metal wiring 471b may be gold (Au).

[0116] In each of the above embodiments, the nozzle 21 may be connected to the discharge flow path, and ink may be discharged from the nozzle 21 while circulating liquid from the supply flow path to the discharge flow path via the nozzle 21. For example, as shown in FIG. 14, in addition to the supply port 44 located on the -X direction side, a discharge port 200 located on the +X direction side may be provided, and two nozzle communication paths 16 may be connected by a flow path extending in the X-axis direction, and the nozzle 21 may be provided in the middle of the connection portion. In this case, the flow of ink is controlled by a pump (not shown) so that the ink supplied from the supply port 44 flows in the order of the pressure chamber 12 on the -X direction side, the nozzle communication path 16, and the pressure chamber 12 on the +X direction side, and is discharged from the discharge port 200. By performing a circulation operation consisting of a series of supply and discharge of ink as described above while discharging ink from the nozzle 21, it is possible to suppress an increase in viscosity due to ink evaporation in the vicinity of the nozzle 21. 14 has been described as a case in which two pressure chambers 12 communicate with one nozzle 21 and ink is ejected from one nozzle 21 by driving two piezoelectric elements 300, but one pressure chamber 12 may also communicate with one nozzle 21. For example, in FIG. 14, the piezoelectric element 300 on the +X direction side may not be provided. [Explanation of symbols]

[0117] 10...pressure chamber substrate, 11...partition wall, 12...pressure chamber, 15...communication plate, 16...nozzle communication passage, 17...first manifold portion, 18...second manifold portion, 19...supply communication passage, 20...nozzle plate, 21...nozzle, 30...protective substrate, 31...holding portion, 32...through hole, 40...case member, 41...accommodation portion, 42...third manifold portion, 43...connection port, 44...supply port, 45...compliance substrate, 46...sealing film, 47...fixed substrate, 48...opening, 49...compliance portion, 50...diaphragm, 51...elastic film, 52...insulating film, 60...first electrode, 70...piezoelectric body, 71...groove portion, 80...second electrode, 85...wiring portion, 91...individual lead electrode, 92...common lead electrode, 93,93a,93b,93c,93d,93e,93f,93 g, 93h, 93i, 93j...measurement lead electrodes, 100...manifold, 120...wiring board, 121...head circuit, 300...piezoelectric element, 310...active portion, 320...inactive portion, 401, 402, 403, 404, 405, 406, 407, 408, 409, 410, 451, 461...resistance wiring, 500...liquid ejection device, 510...liquid ejection head, 55 0...ink tank, 552...tube, 560...transport mechanism, 562...transport roller, 564...transport rod, 566...transport motor, 570...moving mechanism, 572...carriage, 574...transport belt, 576...moving motor, 577...pulley, 580...control unit, G1...first pressure chamber group, G2...second pressure chamber group, G3...third pressure chamber group, G4...fourth pressure chamber group.

Claims

1. a piezoelectric element including a first electrode, a second electrode, and a piezoelectric body, the piezoelectric body being provided between the first electrode and the second electrode in a stacking direction in which the first electrode, the second electrode, and the piezoelectric body are stacked; a vibration plate provided on one side of the piezoelectric element in the stacking direction, the vibration plate being deformed by driving the piezoelectric element; a pressure chamber substrate provided on one side of the vibration plate in the stacking direction, the pressure chamber substrate having a plurality of pressure chambers whose volumes change in response to deformation of the vibration plate; A wiring board; a first wiring electrically connecting the wiring board and the first electrode; a second wiring electrically connecting the wiring board and the second electrode; a temperature detection section electrically connected to the wiring board for detecting a temperature of the pressure chamber, the temperature detection section being arranged to detect a temperature of the pressure chamber.

2. The liquid ejection head according to claim 1 , wherein the temperature detection portion is made of the same material as the first electrode.

3. The liquid ejection head according to claim 1 , wherein the temperature detection portion is made of the same material as the second electrode.

4. The liquid ejection head according to claim 1 , wherein the temperature detection portion is made of the same material as either the first wiring or the second wiring.

5. 5. The liquid ejection head according to claim 1, further comprising a plurality of the temperature detection units provided corresponding to a plurality of pressure chamber groups formed by the plurality of the pressure chambers.

6. When a direction intersecting the stacking direction is defined as a first direction, 6. The liquid ejection head according to claim 5, wherein the plurality of pressure chambers form a pressure chamber row in which the plurality of pressure chambers are aligned in the first direction, and the plurality of pressure chamber groups include a first pressure chamber group formed by the plurality of pressure chambers located on one side of the pressure chamber row in the first direction, and a second pressure chamber group formed by the plurality of pressure chambers located on the other side of the pressure chamber row in the first direction.

7. When a direction intersecting the stacking direction is a first direction, and a direction intersecting the stacking direction and the first direction is a second direction, 6. The liquid ejection head according to claim 5, wherein the plurality of pressure chamber groups include a first pressure chamber row in which the plurality of pressure chambers are aligned in the first direction, and a second pressure chamber row separated from the first pressure chamber row in the second direction and in which the plurality of pressure chambers are aligned in the first direction.

8. When a direction intersecting the stacking direction is a first direction, and a direction intersecting the stacking direction and the first direction is a second direction, the plurality of pressure chambers form a first pressure chamber row in which the plurality of pressure chambers are aligned in the first direction, and a second pressure chamber row spaced apart from the first pressure chamber row in the second direction and in which the plurality of pressure chambers are aligned in the first direction, 6. The liquid ejection head according to claim 5, wherein the plurality of pressure chamber groups include a first pressure chamber group formed by a plurality of the pressure chambers located on one side of the first pressure chamber row in the first direction, a second pressure chamber group formed by a plurality of the pressure chambers located on the other side of the first pressure chamber row in the first direction, a third pressure chamber group formed by a plurality of the pressure chambers located on the one side of the second pressure chamber row in the first direction, and a fourth pressure chamber group formed by a plurality of the pressure chambers located on the other side of the second pressure chamber row in the first direction.

9. When a direction intersecting the stacking direction is defined as a first direction, the first electrodes are provided individually for the plurality of pressure chambers aligned in the first direction, the second electrode is provided in common to the plurality of pressure chambers, the first electrode is provided on the one side of the piezoelectric body in the stacking direction, 9. The liquid ejection head according to claim 1, wherein the second electrode is provided on the other side of the piezoelectric body in the stacking direction.

10. The liquid ejection head according to claim 9, characterized in that the wiring board is provided with a head circuit, and the head circuit is capable of applying a drive voltage that varies in accordance with the amount of liquid ejected to the first electrode via the first wiring, and applying a constant holding voltage to the second electrode via the second wiring regardless of the amount of liquid ejected.

11. 11. The liquid ejection head according to claim 9, wherein the first wiring is provided in the first direction between the second wiring and a connection portion of the temperature detection portion to the wiring board.

12. 11. The liquid ejection head according to claim 9, wherein a connection portion of the temperature detection portion to the wiring board is provided between the first wiring and the second wiring in the first direction.

13. A resistance acquisition unit that acquires an electrical resistance value of the temperature detection unit; 13. The liquid ejection head according to claim 1, further comprising: a temperature acquisition unit that acquires a temperature when the piezoelectric element is driven based on the electrical resistance value acquired by the resistance acquisition unit.

14. The liquid ejection head according to claim 13 , wherein the resistance acquisition unit acquires the electrical resistance value by either a two-terminal measurement method or a four-terminal measurement method.

15. The temperature sensor further includes a storage unit that stores in advance a correspondence relationship between temperature and electrical resistance value of the material of the temperature sensor, The liquid ejection head according to claim 14 , wherein the temperature acquisition unit acquires the temperature when the piezoelectric element is driven based on the correspondence relationship stored in the memory unit and the electrical resistance value acquired by the resistance acquisition unit.

16. A liquid ejection head according to any one of claims 1 to 15, a control unit that controls the liquid ejection operation from the liquid ejection head.

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