Liquid ejecting head and liquid ejecting apparatus

Abstract

To reduce the influence of noise on a resistor for temperature detection while inhibiting adsorption of moisture.SOLUTION: A liquid ejecting head comprises: a pressure chamber substrate including a pressure chamber line having a plurality of pressure chambers arranged in a first direction; a plurality of individual electrodes; piezoelectric bodies laminated on the plurality of individual electrodes and driven to apply a pressure to a liquid inside the plurality of pressure chambers; a common electrode including at least one electrode laminated on the piezoelectric bodies; and a detection resistor disposed on a lower side of the piezoelectric bodies in the lamination direction and at a position not overlapping the plurality of individual electrodes, formed from the same material as the plurality of individual electrodes and the common electrode, and configured to change a resistance value in response to a temperature of the liquid inside the plurality of pressure chambers. The detection resistor includes an overlapping region, which overlaps the common electrode, and a non-overlapping region, which does not overlap the common electrode, at a cross-section where the pressure chamber substrate is sectioned at a position where the pressure chamber is present on a plane parallel to the longitudinal direction of the plurality of pressure chambers and the lamination direction.SELECTED DRAWING: Figure 4

Description

[Technical field]

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

[0002] Patent Document 1 describes that in a liquid ejection head equipped with a piezoelectric element, in order to detect the temperature of the liquid in a pressure chamber, wiring of a resistor whose resistance value changes in response to temperature change is arranged near the pressure chamber. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-124599 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the technology described in Patent Document 1, the resistor is arranged covered with the piezoelectric body (see FIG. 5). In this case, the resistor is affected by noise caused by the drive current flowing through the drive wiring for driving the piezoelectric element. In order to relatively reduce the effect of noise, it is conceivable to limit the range in which the common electrode is arranged on the piezoelectric body so that the range in which the common electrode is provided does not overlap the position in which the resistor is arranged. Here, the common electrode provided on the upper part of the piezoelectric body has a function of suppressing moisture adsorption to the piezoelectric body. From the viewpoint of suppressing moisture adsorption, it is not desirable to limit the range of the common electrode unnecessarily. Therefore, a technology that reduces the effect of noise on the resistor while suppressing moisture adsorption has been desired. [Means for solving the problem]

[0005] According to one embodiment of the present disclosure, there is provided a liquid ejection head, the liquid ejection head comprising: a pressure chamber substrate provided with a pressure chamber array including a plurality of pressure chambers arranged in a first direction, a plurality of individual electrodes provided individually for the plurality of pressure chambers, a piezoelectric body laminated on each of the plurality of individual electrodes and driven to apply pressure to liquid inside the plurality of pressure chambers, a common electrode provided in common to the plurality of pressure chambers and including at least one electrode laminated on the piezoelectric body, and a detection resistor disposed below the piezoelectric body in a lamination direction in which the plurality of individual electrodes, the piezoelectric body, and the common electrode are laminated, at a position not overlapping with the plurality of individual electrodes, the detection resistor being made of the same material as at least one of the plurality of individual electrodes and the common electrode, and the resistance value of which changes depending on the temperature of the liquid inside the plurality of pressure chambers, in a cross section of the pressure chamber substrate cut at a position where the pressure chambers are present in a plane parallel to the longitudinal direction and the lamination direction of the plurality of pressure chambers, the detection resistor includes an overlapping region that overlaps with the common electrode and a non-overlapping region that does not overlap with the common electrode. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is a schematic diagram illustrating a schematic configuration of a liquid ejection device. [Diagram 2] 2 is a block diagram showing a schematic configuration of the functions of a control unit and a liquid ejection head. FIG. [Diagram 3] FIG. 2 is an exploded perspective view showing the configuration of a liquid ejection head. [Figure 4] FIG. 2 is an explanatory diagram showing the configuration of a liquid ejection head in a plan view. [Diagram 5] 5 is a cross-sectional view showing the VV cross section of the liquid ejection head of FIG. [Figure 6] 4 is an enlarged cross-sectional view of the vicinity of a piezoelectric element in a first pressure chamber row. FIG. [Figure 7] 7 is a cross-sectional view showing the VII-VII cross section of the liquid ejection head in FIG. [Figure 8] 4 is an enlarged cross-sectional view of the vicinity of the piezoelectric element according to the first alternative embodiment. FIG. [Figure 9] 11 is an enlarged cross-sectional view of the vicinity of a piezoelectric element according to another embodiment 2. FIG. [Figure 10] FIG. 13 is an explanatory diagram of the arrangement of second electrodes according to another embodiment 3. [Figure 11] FIG. 13 is an explanatory diagram showing, in plan view, the configuration of a liquid ejection head according to another embodiment 6. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] A. Embodiment: Fig. 1 is a schematic diagram showing the general configuration of a liquid ejection device 1 equipped with a liquid ejection head 100. In Fig. 1, an XYZ orthogonal coordinate system is set for ease of understanding. The X-axis and Y-axis are along a horizontal plane, and the Z-axis is along the vertical direction. However, this is not limited to this depending on the direction in which the liquid ejection device 1 is placed. Orthogonal includes the range of 90°±10°. A similar XYZ orthogonal coordinate system is set in Fig. 2 and subsequent drawings.

[0008] The liquid ejection device 1 is an inkjet printer that ejects ink, as an example of a liquid, to print an image on a medium, which is printing paper P. The medium onto which the liquid ejection device 1 ejects ink is not limited to printing paper P, and may be plastic, film, fiber, fabric, leather, metal, glass, wood, ceramics, etc.

[0009] The liquid ejection device 1 includes a liquid ejection head 100 for ejecting liquid, a liquid container 310, a head moving mechanism 320, a transport mechanism 330, and a control unit 500.

[0010] The liquid ejection head 100 has a plurality of nozzles 21 that eject liquid, and ejects liquid supplied from a liquid container 310 onto printing paper P. The plurality of nozzles 21 are arranged along the Y-axis direction. The structure of the liquid ejection head 100 will be described in detail later.

[0011] Liquid container 310 stores the liquid to be ejected from liquid ejection head 100. The liquid stored in liquid container 310 is supplied to liquid ejection head 100 via a resin tube 312. Liquid container 310 is, for example, a bag-shaped liquid pack made of a flexible film.

[0012] The head moving mechanism 320 includes a carriage 322 that carries the liquid ejection head 100, a drive belt 324 to which the carriage 322 is fixed, and a movement motor 326 and a pulley 327 that move the drive belt 324 back and forth in the main scanning direction. The movement motor 326 moves the drive belt 324 back and forth in the main scanning direction, causing the carriage 322 and the liquid ejection head 100 to move back and forth in the main scanning direction. The main scanning direction is the +X direction and the -X direction. The sub-scanning direction is a direction that intersects with the main scanning direction and is the +Y direction and the -Y direction. In the illustrated example, liquid is ejected from the nozzle 21 in the +Z direction.

[0013] The transport mechanism 330 includes three transport rollers 332, a transport rod 334 to which the transport rollers 332 are attached, and a transport motor 336. The transport motor 336 drives and rotates the transport rod 334, whereby the printing paper P is transported in the sub-scanning direction.

[0014] 2 is a block diagram showing a schematic configuration of the functions of the control unit 500 and the liquid ejection head 100. The liquid ejection head 100 includes a piezoelectric element 150, a temperature detection unit 410, and a temperature detection circuit 450. The detailed configuration of the liquid ejection head 100 will be described later. The temperature detection circuit 450 may be provided outside the liquid ejection head 100.

[0015] The piezoelectric element 150 is a driving element for applying pressure to the liquid in a pressure chamber of the liquid ejection head 100, which will be described later.

[0016] The temperature detection unit 410 is configured with resistive wiring used for temperature detection. In this specification, the resistive wiring used for detecting temperature is called a detection resistor. The temperature detection unit 410 will be described in detail later.

[0017] The temperature detection circuit 450 estimates the temperature of the liquid in the pressure chamber by utilizing the characteristic that the electrical resistance value of resistive wiring made of metal, semiconductor, or the like changes with temperature.

[0018] The temperature detection circuit 450 includes a power supply unit 451 and a resistance measurement unit 452. The power supply unit 451 is, for example, a constant current circuit. The power supply unit 451 passes a constant current through the temperature detection unit 410 under control of the temperature management unit 550. The resistance measurement unit 452 acquires the resistance value of the detection resistor of the temperature detection unit 410 based on the current value of the constant current passed by the power supply unit 451 to the temperature detection unit 410 and the voltage value across both ends of the detection resistor included in the temperature detection unit 410. The resistance measurement unit 452 outputs the acquired resistance value of the detection resistor of the temperature detection unit 410 to the temperature management unit 550. The resistance measurement unit 452 is also referred to as a "resistance value acquisition unit."

[0019] The control unit 500 controls the entire liquid ejection device 1. The control unit 500 is a microcomputer including a CPU (Central Processing Unit) 501 and a memory 502. Various programs executed by the CPU 501 are stored in the memory 502. A conversion table TB, which will be described later, is also stored in the memory 502. The CPU 501 executes the programs stored in the memory 502 to function as a head control unit 520 and a temperature management unit 550. Note that the control unit 500 may be realized by one or more processing circuits, such as a field programmable gate array (FPGA) or an application specific integrated circuit (ASIC), instead of a CPU.

[0020] The head control unit 520 controls the reciprocating movement of the carriage 322 in the main scanning direction and the transport movement of the print paper P in the sub-scanning direction. The head control unit 520 also controls the ejection of liquid onto the print paper P by driving the piezoelectric element 150. In this embodiment, the head control unit 520 determines a drive waveform for driving the piezoelectric element 150 based on the temperature of the liquid in the pressure chamber obtained from the temperature management unit 550, and drives the piezoelectric element 150 with a drive signal of the determined drive waveform. Thus, the piezoelectric element 150 can be driven in accordance with the temperature of the liquid in the pressure chamber. The head control unit 520 is also referred to as a "drive waveform determination unit."

[0021] The temperature management unit 550 acquires the temperature in the vicinity of the pressure chamber using the resistance value of the detection resistor of the temperature detection unit 410 acquired from the resistance measurement unit 452 and the conversion table TB. In this embodiment, the temperature of the liquid in the pressure chamber can be detected by the acquired temperature in the vicinity of the pressure chamber. For example, the acquired temperature in the vicinity of the pressure chamber may be treated as the temperature of the liquid in the pressure chamber. Alternatively, a value obtained from the acquired temperature in the vicinity of the pressure chamber by a predetermined method may be treated as the temperature of the liquid in the pressure chamber. The conversion table TB includes information indicating the correspondence between the electrical resistance value of the detection resistor and the temperature. The temperature management unit 550 outputs the acquired temperature of the liquid in the pressure chamber to the head control unit 520. The temperature management unit 550 may calculate the temperature of the liquid in the pressure chamber using the resistance value of the detection resistor of the temperature detection unit 410 and a temperature calculation formula stored in advance in the storage unit 584. The temperature management unit 550 is also called a "temperature acquisition unit".

[0022] The detailed configuration of the liquid ejection head 100 will be described with reference to Fig. 3 to Fig. 5. Fig. 3 is an exploded perspective view showing the configuration of the liquid ejection head 100. Fig. 4 is an explanatory diagram showing the configuration of the liquid ejection head 100 in a plan view. In this specification, "plan view" means a state in which an object is viewed along the stacking direction. Fig. 5 is a cross-sectional view showing the VV cross section of the liquid ejection head 100 in Fig. 4.

[0023] 3, the liquid ejection head 100 includes a pressure chamber substrate 10, a communication substrate 15, a nozzle substrate 20, a compliance substrate 25, a protective substrate 30, a case member 40, a vibration plate 130, a plurality of piezoelectric elements 150, a plurality of individual electrodes 171, a common electrode 172, a plurality of wirings 175, a wiring substrate 200, a temperature detection unit 410, and a temperature detection circuit 450. Note that in FIG. 3, the vibration plate 130 (see FIG. 5), the piezoelectric elements 150 (see FIG. 5), the temperature detection unit 410 (see FIG. 4), and the temperature detection circuit 450 (see FIG. 5) are omitted from illustration.

[0024] The pressure chamber substrate 10, the communication substrate 15, the nozzle substrate 20, the compliance substrate 25, the protective substrate 30, the case member 40, the vibration plate 130, and the piezoelectric element 150 are laminated members. The liquid ejection head 100 is formed by stacking these laminated members. The direction in which the laminated members that form the liquid ejection head 100 are stacked is also called the "stacking direction." In this embodiment, the stacking direction coincides with the Z-axis direction. With respect to a predetermined reference position, the +Z direction side is also called the "lower side," and the -Z direction side is also called the "upper side."

[0025] The pressure chamber substrate 10 is formed of a silicon single crystal substrate. Alternatively, the pressure chamber substrate 10 may be formed of a metal such as stainless steel (SUS) or nickel (Ni), a ceramic material such as zirconia (ZrO2) or alumina (Al2O3), a glass ceramic material, or an oxide material such as magnesium oxide (MgO) or lanthanum aluminate (LaAlO3).

[0026] As shown in FIG. 4, a plurality of pressure chambers 12 are formed in the pressure chamber substrate 10. The pressure chambers 12 are spaces for applying pressure to liquid. In the example shown in FIG. 4, a first pressure chamber row L1 including a plurality of pressure chambers 12 arranged along the Y-axis direction and a second pressure chamber row L2 including a plurality of pressure chambers 12 arranged along the Y-axis direction are formed in the pressure chamber substrate 10. The direction in which the plurality of pressure chambers 12 are arranged (Y-axis direction) is referred to as the arrangement direction. The first pressure chamber row L1 and the second pressure chamber row L2 are arranged to be aligned along a direction (X-axis direction) intersecting the arrangement direction. The pressure chambers 12 belonging to the first pressure chamber row L1 and the pressure chambers 12 belonging to the second pressure chamber row L2 are arranged to be staggered in position in the arrangement direction (Y-axis direction). The arrangement direction in which the plurality of pressure chambers 12 are arranged is also referred to as the "first direction".

[0027] 3, the communication substrate 15 is disposed below the pressure chamber substrate 10. The communication substrate 15 is fixed to the lower surface of the pressure chamber substrate 10 by an adhesive. The communication substrate 15 is formed of, for example, a silicon single crystal substrate.

[0028] As shown in FIG. 5, the communication substrate 15 is formed with an ink supply path 16, a first common liquid chamber 17, a second common liquid chamber 18, and a nozzle communication port 19. The ink supply path 16 is a through hole penetrating the communication substrate 15 in the Z-axis direction. The ink supply path 16 connects the pressure chamber 12 formed in the pressure chamber substrate 10 and the second common liquid chamber 18. The ink supply path 16 is a flow path for introducing liquid into the pressure chamber 12. The first common liquid chamber 17 is formed as a through hole penetrating the communication substrate 15 in the Z-axis direction. The second common liquid chamber 18 is formed as a recess provided on the lower surface (the surface on the -Z side) of the communication substrate 15. The second common liquid chamber 18 connects the ink supply path 16 and the first common liquid chamber 17. The first common liquid chamber 17 and the second common liquid chamber 18, together with a liquid chamber portion 42 formed in the case member 40 described later, constitute a manifold M1 that serves as a common liquid chamber. The nozzle communication ports 19 are through holes that penetrate the communication substrate 15 in the Z-axis direction. The nozzle communication ports 19 connect the pressure chambers 12 and the nozzles 21. The nozzle communication ports 19 are flow paths that discharge liquid from the pressure chambers 12. The communication substrate 15 is formed with the nozzle communication ports 19 in a number corresponding to the number of the nozzles 21.

[0029] 3, the nozzle substrate 20 and the compliance substrate 25 are disposed below the communication substrate 15. The nozzle substrate 20 and the compliance substrate 25 are fixed to the lower surface of the communication substrate 15 with an adhesive. The nozzle substrate 20 is formed of, for example, a silicon single crystal substrate. A plurality of nozzles 21 are formed on the nozzle substrate 20.

[0030] The compliance substrate 25 is disposed around the nozzle substrate 20. As shown in Fig. 5, the compliance substrate 25 covers the respective openings of the first common liquid chamber 17 and the second common liquid chamber 18 provided in the communication substrate 15. The compliance substrate 25 includes a sealing film 26 made of a flexible thin film, and a fixed substrate 27 made of a hard material such as metal.

[0031] 5, the protective substrate 30 is disposed above the pressure chamber substrate 10 via the diaphragm 130. The protective substrate 30 is fixed to the upper surface of the diaphragm 130 with an adhesive. The diaphragm 130 disposed between the pressure chamber substrate 10 and the protective substrate 30 will be described later. The protective substrate 30 is formed from the same material as the pressure chamber substrate 10.

[0032] The protective substrate 30 is provided to protect the piezoelectric element 150 and to reinforce the strength of the pressure chamber substrate 10 and the vibration plate 130. A recess 33 and a through hole 39 are formed in the protective substrate 30. The recess 33 is a recess that opens to the +Z side. The recess 33 is not connected to a liquid flow path. Therefore, liquid does not flow through the recess 33. The through hole 39 is a through hole that penetrates the protective substrate 30 in the Z-axis direction. A wiring substrate 200 is inserted into the through hole 39.

[0033] 3, the case member 40 is disposed above the communication substrate 15. The case member 40 is made of, for example, a resin material.

[0034] 5, the case member 40 has a liquid chamber portion 42, a connection port 43, and two liquid circulation ports 44. As described above, the liquid chamber portion 42, together with the first common liquid chamber 17 and the second common liquid chamber 18 formed in the communication substrate 15, constitute a manifold M1 which serves as a common liquid chamber. The connection port 43 is a through hole which penetrates the case member 40 in the Z-axis direction. The protection substrate 30 is inserted into the connection port 43. The liquid circulation port 44 is a through hole which penetrates the case member 40 in the Z-axis direction. Liquid flows into the liquid ejection head 100 from the liquid circulation port 44.

[0035] The diaphragm 130 is laminated on the upper side of the pressure chamber substrate 10 at a position overlapping with the multiple pressure chambers 12 when viewed in the lamination direction. The diaphragm 130 has a flexible layer 131 and a protective layer 133. The flexible layer 131 is formed on the pressure chamber substrate 10. The flexible layer 131 is formed of, for example, silicon dioxide (SiO2). The protective layer 133 is formed on the flexible layer 131. The protective layer 133 is an insulating film formed of, for example, zirconium oxide (ZrO2).

[0036] The piezoelectric element 150 is disposed on the upper side of the pressure chamber substrate 10 together with the vibration plate 130. More specifically, the piezoelectric element 150 is disposed on the vibration plate 130 inside a recess 33 formed in the protection substrate 30. The piezoelectric element 150 vibrates the vibration plate 130 to apply pressure to the liquid in the pressure chamber 12. When pressure is applied to the liquid in the pressure chamber 12, the liquid is ejected from the nozzle 21 via the nozzle communication port 19.

[0037] 6 is an enlarged cross-sectional view of the vicinity of the piezoelectric element 150 in the first pressure chamber row L1. The piezoelectric element 150 in the first pressure chamber row L1 will be described below as an example, but the second pressure chamber row L2 also has a similar configuration. The piezoelectric element 150 has a first electrode 151, a second electrode 153, and a piezoelectric body 155. The first electrode 151, the piezoelectric body 155, and the second electrode 153 are stacked in this order along the stacking direction.

[0038] The first electrodes 151 are individual electrodes provided in the multiple pressure chambers 12 individually. The first electrodes 151 are formed of a conductive material such as gold (Au), platinum (Pt), iridium (Ir), titanium (Ti), tungsten (W), etc. When viewed in the stacking direction, the first electrodes 151 are disposed at positions overlapping the corresponding pressure chambers 12 on the upper surface of the vibration plate 130. As shown in FIG. 4, the width of the first electrodes 151 is smaller than the width of the pressure chambers 12 in the short side direction (Y-axis direction).

[0039] 6, the +X side end 151a of the first electrode 151 is located outside (on the +X side) of the +X side end 12a of the pressure chamber 12. The -X side end 151b of the first electrode 151 is located outside (on the -X side) of the -X side end 12b of the pressure chamber 12. In other words, the length of the first electrode 151 is longer than the length of the pressure chamber 12 in the longitudinal direction (X-axis direction).

[0040] The piezoelectric body 155 is disposed extending along the arrangement direction (Y-axis direction) of the pressure chambers 12. The piezoelectric body 155 is formed of, for example, lead zirconate titanate (PZT), but may be formed of other materials such as potassium sodium niobate and barium titanate. The piezoelectric body 155 is formed to a thickness in the range of, for example, 1000 nanometers to 4000 nanometers.

[0041] 6, the +X side end 155a of the piezoelectric body 155 is located outside (on the +X side) of the +X side end 12a of the pressure chamber 12. The -X side end 155b of the piezoelectric body 155 is located outside (on the -X side) of the -X side end 12b of the pressure chamber 12. In other words, the length of the piezoelectric body 155 is longer than the length of the pressure chamber 12 in the longitudinal direction (X-axis direction). In this way, the strength of the vibration plate 130 is improved by the piezoelectric body 155 extending to the outside of the pressure chamber 12 in the longitudinal direction.

[0042] 7 is a cross-sectional view taken along line VI-VI in FIG. 4. A groove 157 is formed between two adjacent piezoelectric bodies 155. As shown in FIG. 4, the groove 157 has a rectangular shape when viewed in the stacking direction. As shown in FIG. 7, the groove 157 is provided at a position corresponding to each partition 11. The partition 11 is a wall portion that divides two adjacent pressure chambers 12. The width of the groove 157 in the Y-axis direction is set to be equal to or greater than the width of the partition 11. The groove 157 is formed by forming a layer of the piezoelectric body 155 on the vibration plate 130 and the first electrode 151, and then removing the piezoelectric body 155 in the corresponding region.

[0043] The second electrode 153 is a common electrode provided in common to the multiple pressure chambers 12. As shown in FIG. 4, the second electrode 153 is arranged extending along the arrangement direction (Y-axis direction) of the pressure chambers 12. The second electrode 153 is arranged in the first pressure chamber row L1 and the second pressure chamber row L2 over a range overlapping with all of the multiple pressure chambers 12 belonging to the pressure chamber row. The second electrode 153 may be formed of the same material as the first electrode 151, or may be formed of a different material. As shown in FIG. 7, the second electrode 153 is also provided on the side surface of the groove portion 157 of the piezoelectric body 155 and on the protective layer 133 which is the bottom surface of the groove portion 157. In this embodiment, by providing the second electrode 153 in each of the first pressure chamber row L1 and the second pressure chamber row L2, unnecessary power consumption can be prevented when only one of the first pressure chamber row L1 or the second pressure chamber row L2 is driven.

[0044] The first electrode 151 and the second electrode 153 are both electrically connected to a drive circuit 201 provided on a wiring board 200 (see FIG. 5). A drive signal is applied to the first electrode 151. The drive signal varies depending on the amount of liquid ejected. In this embodiment, the waveform of the drive signal varies depending on the temperature of the liquid in the pressure chamber 12. A reference voltage signal is applied to the second electrode 153. The reference voltage signal is constant regardless of the amount of liquid ejected. The amount of liquid ejected is the amount of volume change required for the pressure chamber 12. When a potential difference occurs between the first electrode 151 and the second electrode 153, the piezoelectric body 155 is deformed. The deformation of the piezoelectric body 155 causes the vibration plate 130 to vibrate, changing the volume of the pressure chamber 12. The change in volume of the pressure chamber 12 applies pressure to the liquid contained in the pressure chamber 12, and the liquid is ejected from the nozzle 21 through the nozzle communication port 19.

[0045] 4 and 6, individual electrode 171 and common electrode 172, which will be described later, function as drive wiring for applying a voltage to piezoelectric body 155 to drive piezoelectric body 155. Individual electrode 171 connects first electrode 151 to wiring board 200. Wiring 175 connects individual electrode 171 and first electrode 151 in the vicinity of end 151b on the -X side of first electrode 151. Thus, first electrode 151, which is an individual electrode, is electrically connected to wiring board 200.

[0046] 4, in each of the first pressure chamber row L1 and the second pressure chamber row L2, the common electrode 172 connects the second electrode 153, which is the corresponding common electrode, to the wiring substrate 200. The common electrode 172 has an extension portion 172a, an extension portion 172b, a connection portion 172c, and a connection portion 172d.

[0047] 4 and 6, the extension 172a extends along the short side direction (Y axis direction) of the pressure chamber 12 at a position corresponding to the end 12a on the +X side of the pressure chamber 12. The extension 172b extends along the short side direction (Y axis direction) of the pressure chamber 12 at a position corresponding to the end 12b on the -X side of the pressure chamber 12.

[0048] The connection portion 172c is disposed near the end of the extension portion 172b on the -Y side, and extends from the extension portion 172b toward the wiring board 200. The connection portion 172c extends along a direction having a predetermined inclination with respect to the X-axis. For example, the connection portion 172c extends along the axial direction when the X-axis is rotated 20 degrees clockwise in the XY plane. An end of the connection portion 172c is connected to the wiring board 200. Therefore, one end of the second electrode 153, which is a common electrode, is electrically connected to the wiring board 200.

[0049] Connection portion 172d is disposed near the end of extension portion 172b on the +Y side, and extends from extension portion 172b toward wiring substrate 200. Connection portion 172d extends in the same direction as connection portion 172c. An end of connection portion 172d is connected to wiring substrate 200. Therefore, the other end of second electrode 153, which is a common electrode, is electrically connected to wiring substrate 200.

[0050] 5, the individual electrodes 171 and the common electrode 172 are arranged such that a portion thereof is exposed in a through hole 39 formed in the protective substrate 30. The individual electrodes 171 and the common electrode 172 are electrically connected to the wiring substrate 200 in the through hole 39.

[0051] The individual electrodes 171 and the common electrode 172 are formed from a conductive material such as gold (Au), copper (Cu), titanium (Ti), tungsten (W), nickel (Ni), chromium (Cr), platinum (Pt), or aluminum (Al). The individual electrodes 171 and the common electrode 172 are formed in the same layer. However, the individual electrodes 171 and the common electrode 172 are not electrically connected. Compared to a case in which the individual electrodes 171 and the common electrode 172 are formed in different layers, the manufacturing process can be simplified and costs can be reduced.

[0052] The wiring board 200 is formed of, for example, a flexible board (FPC: Flexible Printed Circuit).

[0053] 5, a driving circuit 201 and a temperature detection circuit 450 (described later) are provided on the wiring board 200. The driving circuit 201 generates a driving signal for driving the piezoelectric element 150 based on a control signal supplied from a head control unit 520 of the control unit 500.

[0054] 4, the temperature detection unit 410 includes a first detection resistor 411, a second detection resistor 412, a first detection lead electrode 413, and a second detection lead electrode 414. The resistance measurement unit 452 acquires the resistance value of the combined resistance of these resistors.

[0055] As shown in FIG. 4, the first detection resistor 411 includes a first portion 411a, a second portion 411b, and a third portion 411c. The first portion 411a is a portion extending along the longitudinal direction (X-axis direction) of the pressure chamber 12 in the vicinity of the first pressure chamber row L1. The second portion 411b is a portion extending along the longitudinal direction of the pressure chamber 12 in the vicinity of the first pressure chamber row L1 on the opposite side to the side where the first portion 411a is arranged with respect to the first pressure chamber row L1. The third portion 411c is a portion extending along the arrangement direction (Y-axis direction) without bending in the vicinity of the first pressure chamber row L1, and connecting the first portion 411a and the second portion 411b. Therefore, the first detection resistor 411 is arranged so as to surround the periphery of the first pressure chamber row L1. The vicinity of the first pressure chamber row L1 refers to a position where the distance from each of the first portion 411a, the second portion 411b, and the third portion 411c to the first pressure chamber row L1 is within a predetermined distance and where the resistance value of the first detection resistor 411 changes depending on the temperature of the liquid inside the pressure chamber 12 of the first pressure chamber row L1. In this way, the first detection resistor 411 is disposed at a position where the resistance value changes depending on the temperature of the liquid inside the pressure chamber 12 of the first pressure chamber row L1.

[0056] The second detection resistor 412 includes a first portion 412a, a second portion 412b, and a third portion 412c, similar to the first detection resistor 411. The second detection resistor 412 is disposed in the vicinity of the second pressure chamber row L2 so as to surround the periphery of the second pressure chamber row L2. The vicinity of the second pressure chamber row L2 refers to a position where the distance from each of the first portion 412a, the second portion 412b, and the third portion 412c to the third pressure chamber row L3 is within a predetermined distance, and where the resistance value of the second detection resistor 412 changes depending on the temperature of the liquid inside the pressure chamber 12 of the second pressure chamber row L2. In this way, the second detection resistor 412 is disposed at a position where the resistance value changes depending on the temperature of the liquid inside the pressure chamber 12 of the second pressure chamber row L2.

[0057] The -X side end of the second portion 411b of the first detection resistor 411 and the +X side end of the second portion 412b of the second detection resistor 412 are connected near the -Y side ends of the first pressure chamber row L1 and the second pressure chamber row L2. Therefore, the first detection resistor 411 and the second detection resistor 412 form a single resistance wiring.

[0058] The first detection lead electrode 413 connects an end of the first portion 411a of the first detection resistor 411 to the wiring board 200 near the end of the first pressure chamber row L1 on the -Y side. The second detection lead electrode 414 connects an end of the first portion 412a of the second detection resistor 412 to the wiring board 200 near the end of the second pressure chamber row L2 on the -Y side. Thus, one end and the other end of a single resistive wiring formed by the first detection resistor 411 and the second detection resistor 412 are electrically connected to the wiring board 200.

[0059] The first detection lead electrode 413 and the second detection lead electrode 414 are disposed in the same layer as the individual electrode 171 and the common electrode 172 in the lamination direction. The first detection lead electrode 413 and the second detection lead electrode 414 are formed of the same material as the individual electrode 171 and the common electrode 172. The first detection lead electrode 413 and the second detection lead electrode 414 are formed together with the individual electrode 171 and the common electrode 172 in the process of forming the individual electrode 171 and the common electrode 172. However, the first detection lead electrode 413 and the second detection lead electrode 414 are not electrically connected to the individual electrode 171 and the common electrode 172. Compared to the case where the first detection lead electrode 413 and the second detection lead electrode 414 are formed in a layer different from the individual electrode 171 and the common electrode 172, the manufacturing process can be simplified and costs can be reduced.

[0060] 6, the first detection resistor 411 is provided on the -Z side surface of the diaphragm 130. Specifically, the first detection resistor 411 is disposed between the diaphragm 130 and the piezoelectric body 155 in the stacking direction (Z-axis direction) and is covered by the piezoelectric body 155. The second detection resistor 412 is similar.

[0061] The first detection resistor 411 and the second detection resistor 412 are disposed in the same layer as the first electrode 151 in the stacking direction. The first detection resistor 411 and the second detection resistor 412 are formed of the same material as the first electrode 151. The first detection resistor 411 and the second detection resistor 412 are formed of, for example, gold (Au), platinum (Pt), iridium (Ir), titanium (Ti), tungsten (W), or the like, similar to the first electrode 151. These materials are conductive and have temperature-dependent electrical resistance values.

[0062] The first detection resistor 411 and the second detection resistor 412 are formed together with the first electrode 151 in the process of forming the first electrode 151. However, the first detection resistor 411 and the second detection resistor 412 are not electrically connected to the first electrode 151. Compared to the case where the first detection resistor 411 and the second detection resistor 412 are formed in a layer different from the first electrode 151, the manufacturing process can be simplified and costs can be reduced.

[0063] Next, a characteristic configuration of this embodiment will be described. In the following, the first detection resistor 411 will be described as an example, but the second detection resistor 412 also has a similar configuration.

[0064] A part of the first detection resistor 411 overlaps with the second electrode 153, which is a common electrode. In addition, another part of the first detection resistor 411 does not overlap with the second electrode 153. In the example shown in FIG. 6, the area overlapping with the second electrode 153 is illustrated as a first area R1, and the area not overlapping with the second electrode 153 is illustrated as a second area R2. The first area R1 is also called an "overlapping area". The second area R2 is also called a "non-overlapping area". As shown in FIG. 4, in a range where the first detection resistor 411 is arranged along the arrangement direction (Y-axis direction), a part of the first detection resistor 411 overlaps with the second electrode 153, and another part of the first detection resistor 411 does not overlap with the second electrode 153. In a range where the first detection resistor 411 is arranged along the longitudinal direction (X-axis direction) of the pressure chamber 12, the first detection resistor 411 is arranged so as not to overlap with the second electrode 153.

[0065] By arranging the first detection resistor 411 in this manner, it is possible to suppress adsorption of moisture and reduce the influence of noise on the first detection resistor 411. As a result, it is possible to improve the accuracy of temperature detection.

[0066] As shown in FIG. 6, in the longitudinal direction (X-axis direction) of the pressure chamber 12, the length of the first region R1 is shorter than the length of the second region R2, so that the effect of noise on the first detection resistor 411 can be reduced compared to a configuration in which the length of the first region R1 is longer than the length of the second region R2 in the longitudinal direction.

[0067] Furthermore, in the longitudinal direction (X-axis direction) of the pressure chamber 12, the second region R2 is located farther from the pressure chamber 12 than the first region R1. This is because, at a position away from the pressure chamber 12, even if the second electrode 153 is not disposed on the upper part of the piezoelectric body 155, the effect of moisture adsorption to the piezoelectric body 155 is small.

[0068] 4 and 6, the width of the first detection resistor 411 in the X-axis direction is increased in the range extending along the Y-axis direction, so that the cross-sectional area of ​​the first detection resistor 411 can be increased. The same is true for the second detection resistor 412. Therefore, the resistance values ​​of the first detection resistor 411 and the second detection resistor 412 can be reduced.

[0069] Furthermore, since the first detection resistor 411 is arranged without bending, the wiring length of the first detection resistor 411 is shorter than in a mode in which the first detection resistor 411 is bent. The same is true for the second detection resistor 412. Therefore, the resistances of the first detection resistor 411 and the second detection resistor 412 are lower than in a mode in which the first detection resistor 411 is bent. As the resistances of the first detection resistor 411 and the second detection resistor 412 are lower, the value of the current flowing through the first detection resistor 411 and the second detection resistor 412 is larger. When the second electrode 153 overlaps over the entire range of the first detection resistor 411 and the second detection resistor 412 as in the conventional case, not only does the drive current of the piezoelectric element 150 become noise in the current flowing through the first detection resistor 411 and the second detection resistor 412, but the current flowing through the first detection resistor 411 and the second detection resistor 412 becomes noise in the drive current of the piezoelectric element 150.

[0070] However, in the embodiment, the first detection resistor 411 is arranged such that a portion of the first detection resistor 411 overlaps with the second electrode 153, which is a common electrode, and another portion of the first detection resistor 411 does not overlap with the second electrode 153. The same is true for the second detection resistor 412. By arranging the first detection resistor 411 and the second detection resistor 412 in this manner, it is possible to reduce the effect of noise on the first detection resistor 411 and the second detection resistor 412 due to the drive current of the piezoelectric element 150, compared to an embodiment in which the first detection resistor 411 and the second detection resistor 412 do not include a region that does not overlap with the second electrode 153, which is a common electrode.

[0071] B. Other embodiments: B1. Alternative embodiment 1: 8 is an enlarged cross-sectional view of the vicinity of the piezoelectric element 150 in the first pressure chamber row L1 according to Alternative Embodiment 1. The following mainly describes configurations different from the embodiment. Descriptions of configurations similar to the embodiment will be omitted. In Alternative Embodiment 1, the length of the first region R1 is set to be longer than the length of the second region R2 in the longitudinal direction (X-axis direction) of the pressure chamber 12. Compared to an embodiment in which the length of the first region R1 is shorter than the length of the second region R2 in the longitudinal direction, the range in which the second electrode 153 covers the piezoelectric body 155 is wider, and therefore moisture adsorption can be further suppressed.

[0072] Also, similarly to the embodiment, the influence of noise on the first detection resistor 411 can be reduced compared to a mode in which the first detection resistor 411 does not include a range in which it does not overlap with the second electrode 153.

[0073] B2. Alternative embodiment 2: 9 is an enlarged cross-sectional view of the vicinity of the piezoelectric element 150 in the first pressure chamber row L1 in the alternative embodiment 2. The following will focus on configurations that differ from the embodiment, and a description of configurations that are the same as the embodiment will be omitted.

[0074] In another embodiment 2, a first non-electrode layer 163 is provided on the upper side (-Z side) of the piezoelectric body 155 in a range overlapping with the second region R2, which is a non-overlapping region. Furthermore, a second non-electrode layer 165 is provided on the upper side of the first non-electrode layer 163. The first non-electrode layer 163 and the second non-electrode layer 165 are also referred to as "non-electrode layers."

[0075] The first non-electrode layer 163 is formed in the same layer as the second electrode 153. However, the first non-electrode layer 163 is not electrically connected to the second electrode 153. The material forming the first non-electrode layer 163 is the same as that of the second electrode 153. The first non-electrode layer 163 is formed together with the second electrode 153 in the process of forming the second electrode 153. Compared to the case where the first non-electrode layer 163 is formed in a layer different from the second electrode 153, the manufacturing process can be simplified and costs can be reduced.

[0076] The second non-electrode layer 165 is formed in the same layer as the individual electrode 171 and the common electrode 172. However, the second non-electrode layer 165 is not electrically connected to the individual electrode 171 and the common electrode 172. The material forming the second non-electrode layer 165 is the same as that of the individual electrode 171 and the common electrode 172. The second non-electrode layer 165 is formed together with the common electrode 172 in the process of forming the common electrode 172. Compared to the case where the second non-electrode layer 165 is formed from the common electrode 172, the manufacturing process can be simplified and costs can be reduced.

[0077] By providing the first non-electrode layer 163 and the second non-electrode layer 165, the layer thickness in the area where the second electrode 153 and the common electrode 172 are stacked is matched to the layer thickness in the area of ​​the second region R2, which is the non-overlapping area. It is preferable to make the layer thickness in the area where the second electrode 153 and the common electrode 172 are stacked to the layer thickness in the area of ​​the second region R2, which is the non-overlapping area, the same. For example, a plate-shaped sealing member may be placed on the common electrode 172, and by providing the first non-electrode layer 163 and the second non-electrode layer 165, the sealing member can be easily placed.

[0078] B3. Alternative embodiment 3: In the embodiment, as shown in FIG. 6, an example has been described in which the lengths of the first region R1 and the second region R2 in the longitudinal direction of the pressure chamber 12 are constant.

[0079] FIG. 10 is an explanatory diagram of the arrangement of the second electrode 153 according to the third alternative embodiment. In the example shown in FIG. 10, the range set as the first region R1 in the embodiment is represented as the range Rb1, and the range set as the second region R2 is represented as the range Rb2. In the third alternative embodiment, the first detection resistor 411 and the second electrode 153 overlap in the range Rb1. That is, the range Rb1 is set as the first region R1. In the range Rb2, a rectangular cutout is provided in the second electrode 153 along the short side direction (Y-axis direction) of the pressure chamber 12. As a result, along the short side direction (Y-axis direction) of the pressure chamber 12, a region where the first detection resistor 411 and the second electrode 153 overlap and a region where the first detection resistor 411 and the second electrode 153 overlap are alternately arranged. That is, in the range Rb2, the first region R1 and the second region R2 are alternately set along the short side direction of the pressure chamber 12.

[0080] In the range Rb2, the position on the Y axis where the second region R2 is set corresponds to the position of the pressure chamber 12 on the Y axis. Since the pressure chambers 12 are arranged in the Y axis direction at regular intervals, the second region R2 and the first region R1 are alternately arranged in the range Rb2. Therefore, in a cross section of the pressure chamber substrate 10 cut at a position where no pressure chamber 12 exists on a plane parallel to the longitudinal direction and stacking direction of the pressure chamber 12 at the position indicated by the cross section line S1, the first detection resistor 411 does not include the second region R2. Also, in a cross section of the pressure chamber substrate 10 cut at a position where no pressure chamber 12 exists on a plane parallel to the longitudinal direction and stacking direction of the pressure chamber 12 at the position indicated by the cross section line S2, the first detection resistor 411 includes the second region R2.

[0081] In a range where the first electrode 151, which is an individual electrode, and the first detection resistor 411 do not overlap, the first detection resistor 411 is not affected by noise even if the first detection resistor 411 overlaps with the second electrode 153, which is a common electrode. Therefore, in a range where there is no influence of noise, by disposing the second electrode 153 on the piezoelectric body 155, adsorption of moisture can be efficiently suppressed.

[0082] B4. Alternative embodiment 4: Also, instead of providing the second electrodes 153 for the first pressure chamber row L1 and the second pressure chamber row L2 individually, one common electrode may be provided for both the first pressure chamber row L1 and the second pressure chamber row L2. In other words, the two second electrodes 153 in FIG. 4 may be connected to each other.

[0083] B5. Alternative embodiment 5: In the embodiment, an example has been described in which the individual electrodes 171, the connection portions 172c, and the connection portions 172d extend in the same direction (see FIG. 4). Alternatively, the arrangement of the individual electrodes 171, the connection portions 172c, and the connection portions 172d may be different from that shown in FIG.

[0084] FIG. 11 is an explanatory diagram showing another configuration of the liquid ejection head 100 in a plan view. In the example shown in FIG. 11, at the end on the +Y side and the end on the -Y side of the pressure chamber substrate 10, the individual electrode 171, the connection portion 172c, and the connection portion 172d extend along a direction having a predetermined inclination with respect to the X axis. More specifically, at the end on the +Y side of the pressure chamber substrate 10, the individual electrode 171 and the connection portion 172d extend along the axial direction when the X axis is rotated 20 degrees clockwise in the XY plane. At the end on the -Y side of the pressure chamber substrate 10, the individual electrode 171 and the connection portion 172c extend along the axial direction when the X axis is rotated 20 degrees counterclockwise in the XY plane. At the center of the pressure chamber substrate 10 in the Y axis direction, the individual electrode 171 extends along the X axis direction.

[0085] The present disclosure is not limited to the above-mentioned embodiment, and can be realized in various configurations without departing from the spirit of the present disclosure. For example, the technical features in the embodiments corresponding to the technical features in each aspect described in the Summary of the Invention column can be appropriately replaced or combined to solve some or all of the above-mentioned problems or to achieve some or all of the above-mentioned effects. Furthermore, if the technical feature is not described as essential in this specification, it can be appropriately deleted.

[0086] C. Other forms: (1) According to one aspect of the present disclosure, there is provided a liquid ejection head, comprising: a pressure chamber substrate provided with a pressure chamber array including a plurality of pressure chambers arranged in a first direction, a plurality of individual electrodes provided individually for the plurality of pressure chambers, a piezoelectric body laminated on each of the plurality of individual electrodes and driven to apply pressure to liquid inside the plurality of pressure chambers, a common electrode provided in common to the plurality of pressure chambers and including at least one electrode laminated on the piezoelectric body, and a detection resistor disposed below the piezoelectric body in a lamination direction in which the plurality of individual electrodes, the piezoelectric body, and the common electrode are laminated, at a position not overlapping with the plurality of individual electrodes, the detection resistor being formed of the same material as at least one of the plurality of individual electrodes and the common electrode, and the resistance value of which changes depending on the temperature of the liquid inside the plurality of pressure chambers, in a cross section of the pressure chamber substrate cut at a position where the pressure chambers are present in a plane parallel to the longitudinal direction and the lamination direction of the plurality of pressure chambers, the detection resistor includes an overlapping region that overlaps with the common electrode and a non-overlapping region that does not overlap with the common electrode. According to this embodiment, the influence of noise on the detection resistor can be reduced, as compared with an embodiment in which the detection resistor does not include a region where the detection resistor does not overlap with the common electrode.

[0087] (2) In the liquid ejection head of the above aspect, the overlapping region may be located closer to the pressure chamber in the longitudinal direction than the non-overlapping region. At a position away from the pressure chamber, the non-overlapping region is disposed at a position away from the pressure chamber, and the influence of moisture adsorption to the piezoelectric body is reduced even if a common electrode is not disposed above the piezoelectric body.

[0088] (3) In the liquid ejection head of the above aspect, a length of the overlapping region in the longitudinal direction may be longer than a length of the non-overlapping region in the longitudinal direction. According to this embodiment, since the overlapping regions are longer than the non-overlapping regions in the longitudinal direction, adsorption of moisture can be suppressed more effectively than in an embodiment in which the overlapping regions are shorter than the non-overlapping regions in the longitudinal direction.

[0089] (4) In the liquid ejection head of the above aspect, a length of the overlapping region in the longitudinal direction may be shorter than a length of the non-overlapping region in the longitudinal direction. According to this embodiment, since the overlapping region is shorter than the non-overlapping region in the longitudinal direction, the effect of noise on the resistor can be reduced compared to an embodiment in which the overlapping region is longer than the non-overlapping region in the longitudinal direction.

[0090] (5) In the liquid ejection head of the above embodiment, in a region overlapping with the non-overlapping region, a non-electrode layer formed of the same material as the common electrode and not electrically connected to the common electrode may be provided on the upper side of the piezoelectric body in the stacking direction. According to this aspect, by providing the non-electrode layer, the thickness of the layer in the area where the detection resistor is arranged can be made to match the thickness of the layer in the area where the common electrode is laminated.

[0091] (6) In the liquid ejection head of the above aspect, the thickness of the layer in the area where the non-electrode layer is provided may be the same as the thickness of the layer in the area where the common electrode is provided. According to this aspect, by providing the non-electrode layer, the thickness of the layer in the non-overlapping region can be made to match the thickness of the layer in the region where the common electrode is provided.

[0092] (7) In the liquid ejection head of the above aspect, in a cross section of the pressure chamber substrate cut at a position where no pressure chamber is present on a plane parallel to the longitudinal direction of the pressure chamber and the stacking direction, the detection resistor may not include the non-overlapping region. According to this embodiment, since the individual electrodes do not overlap with the detection resistors, even if there is an area where the detection resistors overlap with the common electrode, the detection resistors are not affected by noise. Therefore, in the area where there is no noise effect, the common electrode can be disposed on the piezoelectric body to suppress moisture adsorption.

[0093] (8) The liquid ejection head of the above aspect may further include a wiring board, and the detection resistor may include a first portion extending along the longitudinal direction in the vicinity of the pressure chamber row and having one end connected to the wiring board, a second portion extending along the longitudinal direction in the vicinity of the pressure chamber on the side opposite to the pressure chamber row on which the first portion is located and having one end connected to the wiring board, and a third portion extending along the first direction in the vicinity of the pressure chamber without bending and connecting the other end of the first portion and the other end of the second portion.

[0094] (9) According to another aspect of the present disclosure, there is provided a liquid ejection device including the liquid ejection head of the above aspect, a resistance value acquisition unit that acquires a resistance value of the detection resistor, and a temperature acquisition unit that acquires a temperature in the vicinity of the pressure chamber based on the resistance value acquired by the resistance value acquisition unit. According to this embodiment, it is possible to reduce the influence of noise and improve the accuracy of temperature detection.

[0095] (10) The liquid ejection device according to the above aspect may further include a drive waveform determination section that determines drive waveforms to be applied to the individual electrodes based on the temperature acquired by the temperature acquisition section. According to this aspect, the piezoelectric element can be driven in response to the temperature.

[0096] The present disclosure is not limited to the above-described liquid ejection apparatus, but can be realized in various forms such as a liquid ejection system, a multifunction peripheral including a liquid ejection apparatus, and the like. [Explanation of symbols]

[0097] 1...liquid ejection device, 10...pressure chamber substrate, 11...partition wall, 12...pressure chamber, 12a, 12b...end portion, 15...communication substrate, 16...ink supply path, 17...first common liquid chamber, 18...second common liquid chamber, 19...nozzle communication port, 20...nozzle substrate, 21...nozzle, 25...compliance substrate, 26...sealing film, 27...fixed substrate, 30...protection substrate, 33...recess, 39...through hole, 40...case member, 42...liquid chamber portion, 43...connection port, 44...liquid flow port, 100...liquid Discharge head, 130... vibration plate, 131... flexible layer, 133... protective layer, 150... piezoelectric element, 151... first electrode, 151a, 151b... end portion, 153... second electrode, 155... piezoelectric body, 157... groove portion, 163... first non-electrode layer, 165... second non-electrode layer, 170... wiring portion, 171... individual electrode, 172... common electrode, 172a, 172b... extension portion, 172c, 172d... connection portion, 175... wiring, 200... wiring board, 201... drive circuit, 310... liquid Container, 312...tube, 320...head moving mechanism, 322...carriage, 324...drive belt, 326...movement motor, 327...pulley, 330...transport mechanism, 332...transport roller, 334...transport rod, 336...transport motor, 410...temperature detection unit, 411...first detection resistor, 411a...first portion, 411b...second portion, 411c...third portion, 412...second detection resistor, 412a...first portion, 412b...second portion, 41 2c...third portion, 413...first detection lead electrode, 414...second detection lead electrode, 450...temperature detection circuit, 451...power supply section, 452...resistance measurement section, 500...control section, 501...CPU, 502...memory, 520...head control section, 550...temperature management section, 584...storage section, L1...first pressure chamber row, L2...second pressure chamber row, M1...manifold, P...printing paper, R1...first area, R2...second area, S1, S2...section line, TB...conversion table

Claims

1. A liquid ejection head, a pressure chamber substrate provided with a pressure chamber array including a plurality of pressure chambers arranged in a first direction; A plurality of individual electrodes provided in the plurality of pressure chambers; a piezoelectric body that is laminated on each of the individual electrodes and is driven to apply pressure to the liquid inside the pressure chambers; a common electrode including at least one electrode provided in common to the plurality of pressure chambers and laminated on the piezoelectric body; a detection resistor that is disposed below the piezoelectric body in a stacking direction in which the individual electrodes, the piezoelectric body, and the common electrode are stacked, at a position not overlapping with the individual electrodes, is made of the same material as at least one of the individual electrodes and the common electrode, and has a resistance value that changes in response to the temperature of the liquid inside the pressure chambers; Equipped with in a cross section of the pressure chamber substrate cut at a position where the pressure chambers are present on a plane parallel to a longitudinal direction of the plurality of pressure chambers and the stacking direction, the detection resistor includes an overlapping region that overlaps with the common electrode and a non-overlapping region that does not overlap with the common electrode, Liquid ejection head.

2. 2. The liquid ejection head according to claim 1, the overlapping region is located closer to the pressure chamber than the non-overlapping region in the longitudinal direction; Liquid ejection head.

3. 2. The liquid ejection head according to claim 1, The length of the overlapping region in the longitudinal direction is longer than the length of the non-overlapping region in the longitudinal direction. Liquid ejection head.

4. 2. The liquid ejection head according to claim 1, The length of the overlapping region in the longitudinal direction is shorter than the length of the non-overlapping region in the longitudinal direction. Liquid ejection head.

5. 2. The liquid ejection head according to claim 1, a non-electrode layer formed of the same material as the common electrode and not electrically connected to the common electrode is provided on an upper side of the piezoelectric body in the stacking direction in a region overlapping with the non-overlapping region; Liquid ejection head.

6. 6. The liquid ejection head according to claim 5, The thickness of the layer in the area where the non-electrode layer is provided is the same as the thickness of the layer in the area where the common electrode is provided. Liquid ejection head.

7. 2. The liquid ejection head according to claim 1, the detection resistor does not include the non-overlapping region in a cross section of the pressure chamber substrate cut at a position where the pressure chamber does not exist on a plane parallel to the longitudinal direction of the pressure chamber and the stacking direction; Liquid ejection head.

8. 2. The liquid ejection head according to claim 1, The wiring board further includes: The detection resistor is a first portion extending along the longitudinal direction in the vicinity of the pressure chamber row and having one end connected to the wiring substrate; a second portion that is disposed on a side opposite to the pressure chamber row from the side on which the first portion is disposed, extends along the longitudinal direction in the vicinity of the pressure chamber, and has one end connected to the wiring substrate; a third portion extending along the first direction without bending in the vicinity of the pressure chamber and connecting the other end of the first portion and the other end of the second portion; Contains Liquid ejection head.

9. A liquid ejection device, A liquid ejection head according to any one of claims 1 to 8, a resistance value acquiring unit for acquiring a resistance value of the detection resistor; a temperature acquisition unit that acquires a temperature in the vicinity of the pressure chamber based on the resistance value acquired by the resistance value acquisition unit; A liquid ejection device comprising:

10. The liquid ejection device according to claim 9 , a drive waveform determination unit that determines drive waveforms to be applied to the plurality of individual electrodes based on the temperature acquired by the temperature acquisition unit; The liquid ejection device further comprises:

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