Liquid ejecting head and liquid ejecting apparatus

Abstract

To wire a first detection resistor and a second detection resistor for temperature detection so as to reduce resistance values.SOLUTION: A liquid ejecting head comprises: a pressure chamber substrate provided with a first pressure chamber line including a plurality of pressure chambers and with a second pressure chamber line including a plurality of pressure chambers; a plurality of individual electrodes individually provided to the plurality of pressure chambers; at least one common electrode provided in common to the plurality of pressure chambers; piezoelectric bodies driven to apply a pressure to a liquid inside the plurality of pressure chambers; a first detection resistor designed to change a resistance value in response to a temperature of the liquid inside the plurality of pressure chambers included in the first pressure chamber line; a second detection resistor designed to change a resistance value in response to on a temperature of the liquid inside the plurality of pressure chambers included in the second pressure chamber line; a wiring board; a first coupling terminal that couples one end of the first detection resistor and one end of the second detection resistor in common to the wiring board; and a second coupling terminal that couples another end of the first detection resistor and another end of the second detection resistor in common to the wiring board.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] Since the resistor is wired near the pressure chamber, it is affected by noise caused by the drive current flowing through the drive wiring for driving the piezoelectric element. In addition, in the technology described in Patent Document 1, the resistor is arranged in a meandering manner. Therefore, the resistance of the resistor increases as the wiring length increases. This reduces the current value flowing through the resistor. As a result, the degree of influence of noise of the drive current on the current flowing through the resistor increases. In order to relatively reduce the influence of noise, it is possible to pass a relatively large current through the resistor, but this is not desirable because there is a possibility of an overvoltage state occurring. Therefore, a technology for wiring the resistor so as to reduce the resistance value has been desired. [Means for solving the problem]

[0005] According to one aspect of the present disclosure, there is provided a liquid ejection head, the liquid ejection head comprising: a pressure chamber substrate on which a first pressure chamber row including a plurality of pressure chambers arranged in a first direction and a second pressure chamber row including a plurality of pressure chambers arranged in the first direction are arranged in a second direction intersecting the first direction, a plurality of individual electrodes provided individually for the plurality of pressure chambers in the first pressure chamber row and the second pressure chamber row, at least one common electrode provided in common to the plurality of pressure chambers in the first pressure chamber row and the second pressure chamber row, piezoelectric bodies provided between the plurality of individual electrodes and the at least one common electrode, and driven to apply pressure to liquid inside the plurality of pressure chambers, and a piezoelectric element between the plurality of individual electrodes and the at least one common electrode. the first detection resistor being formed of the same material as at least one of the individual electrodes and at least one common electrode, and having a resistance value that changes in response to the temperature of liquid inside the multiple pressure chambers included in the first pressure chamber row; a second detection resistor being formed of the same material as at least one of the multiple individual electrodes and the at least one common electrode, and having a resistance value that changes in response to the temperature of liquid inside the multiple pressure chambers included in the second pressure chamber row; a wiring board; a first connection terminal that commonly connects one end of the first detection resistor and one end of the second detection resistor to the wiring board; and a second connection terminal that commonly connects the other end of the first detection resistor and the other end of the second detection resistor to the wiring board. [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 of FIG. [Figure 8] FIG. 11 is an explanatory diagram showing the configuration of a liquid ejection head according to another embodiment 2 in a plan view. [Figure 9] 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". The direction intersecting the arrangement direction is also referred to as the "second 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. The second electrode 153 in the first pressure chamber row L1 is also called the "first common electrode". The second electrode 153 in the second pressure chamber row L2 is also called the "second common electrode". 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, it is possible to prevent unnecessary power consumption when only 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 connection portion 172c of the common electrode 172 in the first pressure chamber row L1 is also referred to as the "third connection terminal." The connection portion 172c of the common electrode 172 in the second pressure chamber row L2 is also referred to as the "fourth connection terminal." The connection portion 172d of the common electrode 172 in the first pressure chamber row L1 is also referred to as the "fifth connection terminal." The connection portion 172d of the common electrode 172 in the second pressure chamber row L2 is also referred to as the "sixth connection terminal." The individual electrode 171 in the first pressure chamber row L1 is also referred to as the "seventh connection terminal." The individual electrode 171 in the second pressure chamber row L2 is also referred to as the "eighth connection terminal."

[0053] The wiring board 200 is formed of, for example, a flexible board (FPC: Flexible Printed Circuit).

[0054] 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.

[0055] 4, the temperature detection unit 410 includes a first detection resistor 411, a second detection resistor 412, a first detection lead electrode 415, and a second detection lead electrode 416. The resistance measurement unit 452 acquires the resistance value of the combined resistance of these resistors.

[0056] 4, the first detection resistor 411 is disposed so as to surround the periphery of the first pressure chamber row L1 except for the side of the first pressure chamber row L1 adjacent to the second pressure chamber row L2. The first detection resistor 411 is disposed at a position where its resistance value changes depending on the temperature of the liquid inside the pressure chamber 12 of the first pressure chamber row L1. The second detection resistor 412 is disposed so as to surround the periphery of the second pressure chamber row L2 except for the side of the second pressure chamber row L2 adjacent to the first pressure chamber row L1. The second detection resistor 412 is disposed at a position where its resistance value changes depending on the temperature of the liquid inside the pressure chamber 12 of the second pressure chamber row L2.

[0057] 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.

[0058] 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.

[0059] 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.

[0060] 4, the first detection lead electrode 415 connects the -Y side end of the first detection resistor 411 and the -Y side end of the second detection resistor 412 together to the wiring board 200 near the -Y side ends of the first pressure chamber row L1 and the second pressure chamber row L2. The second detection lead electrode 416 connects the +Y side end of the first detection resistor 411 and the +Y side end of the second detection resistor 412 together to the wiring board 200 near the +Y side ends of the first pressure chamber row L1 and the second pressure chamber row L2. The first detection lead electrode 415 is also called the "first connection terminal". The second detection lead electrode 416 is also called the "second connection terminal".

[0061] The first detection lead electrode 415 and the second detection lead electrode 416 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 415 and the second detection lead electrode 416 are formed of the same material as the individual electrode 171 and the common electrode 172. The first detection lead electrode 415 and the second detection lead electrode 416 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 415 and the second detection lead electrode 416 are not electrically connected to the individual electrode 171 and the common electrode 172. With this configuration, the manufacturing process can be simplified and costs can be reduced compared to the case where the first detection lead electrode 415 and the second detection lead electrode 416 are formed in a different layer from the individual electrode 171 and the common electrode 172.

[0062] Just as a portion of each of the individual electrode 171 and the common electrode 172 is disposed on the piezoelectric body 155 (see FIG. 6), a portion of the first detection lead electrode 415 and a portion of the second detection lead electrode 416 are disposed on the piezoelectric body 155.

[0063] 4, one end of the first detection resistor 411 and one end of the second detection resistor 412 are commonly connected to the wiring board 200, and the other end of the first detection resistor 411 and the other end of the second detection resistor 412 are commonly connected to the wiring board 200. That is, the first detection resistor 411 and the second detection resistor 412 are connected to the wiring board 200 in parallel.

[0064] In this embodiment, in order to reduce the combined resistance of the first detection resistor 411 and the second detection resistor 412, the first detection resistor 411 and the second detection resistor 412 are connected in parallel. For example, the resistance value of the first detection resistor 411 is R1, and the resistance value of the second detection resistor 412 is R2. The combined resistance Rtp when the first detection resistor 411 and the second detection resistor 412 are connected in parallel is R1·R2 / (R1+R2). In order to facilitate understanding of the technology, the resistance values ​​of the first detection lead electrode 415 and the second detection lead electrode 416 are not taken into consideration.

[0065] Assume that the first detection resistor 411 and the second detection resistor 412 are connected in series. Connecting in series means that one end of the first detection resistor 411 and one end of the second detection resistor 412 are individually connected to the wiring board 200, and the other end of the first detection resistor 411 and the other end of the second detection resistor 412 are connected to each other. The other end of the first detection resistor 411 and the other end of the second detection resistor 412 are not connected to the wiring board 200. In this case, the combined resistance Rts of the first detection resistor 411 and the second detection resistor 412 is R1+R2.

[0066] In this way, the combined resistance Rtp when the first detection resistor 411 and the second detection resistor 412 are connected in parallel is lower than the combined resistance Rts when the first detection resistor 411 and the second detection resistor 412 are not connected in parallel.

[0067] The reason why it is desirable to reduce the combined resistance of the first detection resistor 411 and the second detection resistor 412 is as follows. In order to detect the temperature of the ink in the pressure chamber 12, the first detection resistor 411 and the second detection resistor 412 are arranged in the vicinity of the pressure chamber 12. Therefore, the first detection resistor 411 and the second detection resistor 412 are affected by noise caused by the current flowing through the individual electrode 171 and the common electrode 172, which are the drive wiring of the piezoelectric element 150. In order to relatively reduce the influence of the noise, it is possible to pass a relatively large current through the detection resistor, but this is not desirable because it may cause an overvoltage state. Therefore, in this embodiment, by reducing the combined resistance of the first detection resistor 411 and the second detection resistor 412, the current value flowing through the first detection resistor 411 and the second detection resistor 412 can be increased compared to the embodiment in which the first detection resistor 411 and the second detection resistor 412 are connected in series. This reduces the effect of noise due to the drive current of the piezoelectric element 150.

[0068] As shown in FIG. 4, in this embodiment, the width of the first detection lead electrode 415 in the arrangement direction (Y-axis direction) is larger than the width of the individual electrode 171. By increasing the width of the first detection lead electrode 415, the cross-sectional area of ​​the first detection lead electrode 415 can be increased. By increasing the cross-sectional area of ​​the first detection lead electrode 415, the resistance value of the first detection lead electrode 415 can be reduced compared to a mode in which the width of the first detection lead electrode 415 is the same as the width of the individual electrode 171. By decreasing the resistance value of the first detection lead electrode 415, the combined resistance of the temperature detection unit 410 can be reduced. As a result, the current value flowing through the temperature detection unit 410 can be increased. This reduces the effect of noise due to the drive current of the piezoelectric element 150.

[0069] In this embodiment, the distance in the arrangement direction (Y-axis direction) between the first detection lead electrode 415 and the connection portion 172c in the first pressure chamber row L1 is set shorter than the distance in the arrangement direction between the first detection lead electrode 415 and the connection portion 172c in the second pressure chamber row L2. The distance in the arrangement direction between the second detection lead electrode 416 and the connection portion 172d in the first pressure chamber row L1 is set longer than the distance in the arrangement direction between the second detection lead electrode 416 and the connection portion 172d in the second pressure chamber row L2. Since the distance between the first detection lead electrode 415 and the connection portion 172c of the common electrode 172 in the first pressure chamber row L1 is short at one end side (-Y side) in the arrangement direction of the first pressure chamber row L1, the distance between the second detection lead electrode 416 and the connection portion 172d is set longer at the other end side (+Y side) in the arrangement direction of the first pressure chamber row L1. With this configuration, the difference between the magnitude of the electromagnetic induction noise caused by the common electrode 172 to the first lead electrode for detection 415 and the magnitude of the electromagnetic induction noise caused by the common electrode 172 to the second lead electrode for detection 416 is reduced. In other words, a balance can be maintained between the influence of noise on the first lead electrode for detection 415 and the influence of noise on the second lead electrode for detection 416.

[0070] The length of the first detection lead electrode 415 in the extending direction (extension direction) is longer than the length of the connection portion 172c in the first pressure chamber row L1 in the extending direction and is longer than the length of the connection portion 172c in the second pressure chamber row L2 in the extending direction. In the example shown in Fig. 4, the extension direction (X-axis direction) of the first detection lead electrode 415 does not strictly match the extension direction of the connection portion 172c in the first pressure chamber row L1 and the connection portion 172c in the second pressure chamber row L2. "Along the X-axis direction" includes a range of directions inclined ±30° with respect to the X-axis direction, and the extension direction of the connection portion 172c in the first pressure chamber row L1 and the connection portion 172c in the second pressure chamber row L2 is along the X-axis direction.

[0071] Since the length in the extension direction of the connection portion 172c in the first pressure chamber row L1 and the length in the extension direction of the connection portion 172c in the second pressure chamber row L2 are not unnecessarily long, the effect of inductive noise on the first detection lead electrode 415 is reduced.

[0072] B. Other embodiments: B1. Alternative embodiment 1: In the embodiment, an example has been described in which the temperature management unit 550 determines the temperature of the ink in the pressure chamber 12 using the resistance value of the detection resistor of the temperature detection unit 410 obtained from the resistance measurement unit 452 and a conversion table TB pre-stored in the memory 502.

[0073] In the liquid ejection head 100, there are cases where only one of the first pressure chamber row L1 and the second pressure chamber row L2 is driven. Therefore, instead of the conversion table TB, a first conversion table TB1 and a second conversion table TB2 may be stored in advance in the memory 502. The first conversion table TB1 includes information representing the correspondence between the resistance value of the detection resistor of the temperature detection unit 410 and the temperature when the first pressure chamber row L1 and the second pressure chamber row L2 are driven. The second conversion table TB2 includes information representing the correspondence between the resistance value of the detection resistor of the temperature detection unit 410 and the temperature when either the first pressure chamber row L1 or the second pressure chamber row L2 is driven.

[0074] When driving the first pressure chamber row L1 and the second pressure chamber row L2, the temperature management section 550 can obtain the temperature of the ink in the pressure chamber 12 using the resistance value of the detection resistor of the temperature detection section 410 obtained from the resistance measurement section 452 and the first conversion table TB1. When driving either the first pressure chamber row L1 or the second pressure chamber row L2, the temperature management section 550 can obtain the temperature of the ink in the pressure chamber 12 using the resistance value of the detection resistor of the temperature detection section 410 obtained from the resistance measurement section 452 and the second conversion table TB2. The temperature management section 550 is also referred to as a correspondence relationship acquisition section. The first conversion table TB1 is also referred to as a first correspondence relationship. The second conversion table TB2 is also referred to as a second correspondence relationship.

[0075] Even when driving either the first pressure chamber row L1 or the second pressure chamber row L2, the resistance measurement section 452 acquires the combined resistance of the temperature detection section 410 including the first detection resistor 411 and the second detection resistor 412. Therefore, by using either the first conversion table TB1 or the second conversion table TB2 prepared in advance, the accuracy of temperature detection can be improved.

[0076] B2. Alternative embodiment 2: In the alternative embodiment 1, an example has been described in which the first conversion table TB1, which is an example of the first correspondence relationship, and the second conversion table TB2, which is an example of the second correspondence relationship, are used to obtain the temperature of the ink in the pressure chamber 12. However, the first calculation formula F1 and the second calculation formula F2 may be used to obtain the temperature of the ink in the pressure chamber 12. The first calculation formula F1 is a calculation formula for calculating the temperature of the ink based on the resistance value of the detection resistor of the temperature detection unit 410 when the first pressure chamber row L1 and the second pressure chamber row L2 are driven. The second calculation formula is a calculation formula for calculating the temperature of the ink based on the resistance value of the detection resistor of the temperature detection unit 410 when either the first pressure chamber row L1 or the second pressure chamber row L2 is driven. The first calculation formula F1 and the second calculation formula F2 are stored in advance in the memory 502. The first calculation formula F1 is also referred to as the "first correspondence relationship". The second calculation formula F2 is also referred to as the "second correspondence relationship".

[0077] When driving the first pressure chamber row L1 and the second pressure chamber row L2, the temperature management section 550 can determine the temperature of the ink in the pressure chamber 12 using the resistance value of the detection resistor of the temperature detection section 410 acquired from the resistance measurement section 452 and the first calculation formula F1. When driving either the first pressure chamber row L1 or the second pressure chamber row L2, the temperature management section 550 can determine the temperature of the ink in the pressure chamber 12 using the resistance value of the detection resistor of the temperature detection section 410 acquired from the resistance measurement section 452 and the second calculation formula F2. By using either the first calculation formula F1 or the second calculation formula F2 prepared in advance, the accuracy of temperature detection can be improved.

[0078] B3. Alternative embodiment 3: 8 is an explanatory diagram showing in plan view the configuration of a liquid ejection head 100 in another embodiment 2. In another embodiment 2, a first detection lead electrode 415 and a third detection lead electrode 417 connected in parallel connect the -Y side end of the first detection resistor 411 and the -Y side end of the second detection resistor 412 together to the wiring board 200 near the -Y side ends of the first pressure chamber row L1 and the second pressure chamber row L2.

[0079] Further, the second detection lead electrode 416 and the fourth detection lead electrode 418 connected in parallel connect the +Y side end of the first detection resistor 411 and the +Y side end of the second detection resistor 412 together to the wiring board 200 near the +Y side ends of the first pressure chamber row L1 and the second pressure chamber row L2. The third detection lead electrode 417 is also called the "first parallel connection terminal". The fourth detection lead electrode 418 is also called the "second parallel connection terminal".

[0080] The combined resistance of the first detection lead electrode 415 and the third detection lead electrode 417 connected in parallel is lower than the resistance when one first detection lead electrode 415 is used (see FIG. 4). The combined resistance of the second detection lead electrode 416 and the fourth detection lead electrode 418 connected in parallel is lower than the resistance when one second detection lead electrode 416 (see FIG. 4) is used. Thus, the combined resistance of the temperature detection unit 410 can be reduced. As a result, the value of the current flowing through the temperature detection unit 410 can be increased. This reduces the effect of noise due to the drive current of the piezoelectric element 150.

[0081] B4. Alternative embodiment 4: 4 and 6. By increasing the cross-sectional area of ​​the first detection resistor 411 and the second detection resistor 412, the resistance value of each of the first detection resistor 411 and the second detection resistor 412 can be reduced. As a result, the current value flowing through the first detection resistor 411 and the second detection resistor 412 can be increased. This reduces the effect of noise due to the drive current of the piezoelectric element 150.

[0082] B5. Alternative embodiment 5: Also, instead of providing the second electrodes 153 individually for the first pressure chamber row L1 and the second pressure chamber row L2, one common electrode (third common electrode) corresponding to both the first pressure chamber row L1 and the second pressure chamber row L2 may be provided. In other words, the two second electrodes 153 in Fig. 4 may be connected. In this case, the connection portion of the common electrode corresponding to both the first pressure chamber row L1 and the second pressure chamber row L2 with the wiring substrate is also referred to as the "ninth connection terminal".

[0083] B6. Alternative Embodiment 6: 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. 9 is an explanatory diagram showing another configuration of the liquid ejection head 100 in a plan view. In the example shown in FIG. 9, 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 obtained by rotating the X axis by 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 obtained by rotating the X axis by 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, the liquid ejection head comprising: a pressure chamber substrate on which a first pressure chamber row including a plurality of pressure chambers arranged in a first direction and a second pressure chamber row including a plurality of pressure chambers arranged in the first direction are arranged in a second direction intersecting the first direction, a plurality of individual electrodes provided individually for the plurality of pressure chambers in each of the first pressure chamber row and the second pressure chamber row, at least one common electrode provided in common to the plurality of pressure chambers in each of the first pressure chamber row and the second pressure chamber row, piezoelectric bodies provided between the plurality of individual electrodes and the at least one common electrode, and driven to apply pressure to liquid inside the plurality of pressure chambers, and a piezoelectric element between the plurality of individual electrodes and the at least one common electrode. the first detection resistor being formed of the same material as at least one of the individual electrodes and at least one common electrode, and having a resistance value that changes in response to the temperature of liquid inside the multiple pressure chambers included in the first pressure chamber row; a second detection resistor being formed of the same material as at least one of the multiple individual electrodes and the at least one common electrode, and having a resistance value that changes in response to the temperature of liquid inside the multiple pressure chambers included in the second pressure chamber row; a wiring board; a first connection terminal that commonly connects one end of the first detection resistor and one end of the second detection resistor to the wiring board; and a second connection terminal that commonly connects the other end of the first detection resistor and the other end of the second detection resistor to the wiring board. According to this embodiment, the first detection resistor for detecting the temperature of the first pressure chamber row and the second detection resistor for detecting the temperature of the second pressure chamber are commonly connected to the wiring board at one end and commonly connected to the wiring connection at the other end. That is, the first detection resistor and the second detection resistor are connected in parallel. Therefore, the first detection resistor and the second detection resistor can be wired so that the combined resistance of the first detection resistor and the second detection resistor is lower than in an embodiment in which the first detection resistor and the second detection resistor are connected in series.

[0087] (2) In the liquid ejection head of the above aspect, the at least one common electrode may include a first common electrode corresponding to the first pressure chamber row and a second common electrode corresponding to the second pressure chamber row, and may further include a third connection terminal connecting a portion of the first common electrode to the wiring substrate, and a fourth connection terminal connecting a portion of the second common electrode to the wiring substrate. According to this aspect, by providing a common electrode for each of the first pressure chamber row and the second pressure chamber row, it is possible to prevent unnecessary power consumption when only the first pressure chamber row or the second pressure chamber row is driven.

[0088] (3) In the liquid ejection head of the above aspect, a fifth connection terminal for connecting another portion of the first common electrode to the wiring substrate, and a sixth connection terminal for connecting another portion of the second common electrode to the wiring substrate may be further provided.

[0089] (4) In the liquid ejection head of the above embodiment, the distance between the first connection terminal and the third connection terminal in the first direction may be shorter than the distance between the first connection terminal and the fourth connection terminal in the first direction, and the distance between the second connection terminal and the fifth connection terminal in the first direction may be longer than the distance between the second connection terminal and the sixth connection terminal in the first direction. According to this embodiment, at one end side in the first direction, the distance between the first connection terminal and the fourth connection terminal is longer than the distance between the first connection terminal and the third connection terminal, and therefore, by setting the distance between the second connection terminal and the fifth connection terminal shorter than the distance between the second connection terminal and the sixth connection terminal at the other end side in the first direction, it is possible to maintain a balance between the effect of electromagnetic induction noise on the first connection terminal and the effect of electromagnetic induction noise on the second connection terminal.

[0090] (5) In the liquid ejection head of the above aspect, the width of the first connection terminal in the first direction may be larger than the width of the third connection terminal in the first direction. According to this embodiment, the width of the first connection terminal that commonly connects the first resistor and the second resistor to the wiring board is increased, and the cross-sectional area of ​​the first connection terminal is widened, thereby reducing the resistance value of the first connection terminal.

[0091] (6) The liquid ejection head of the above aspect may further include a first parallel connection terminal connected in parallel to the first connection terminal and commonly connecting one end of the first detection resistor and one end of the second detection resistor to the wiring board, and a second parallel connection terminal connected in parallel to the second connection terminal and commonly connecting the other end of the first detection resistor and the other end of the second detection resistor to the wiring board. According to this embodiment, the combined resistance of the first connection terminal and the first parallel connection terminal can be made lower than the resistance of the first connection terminal when one first connection terminal is used, and the combined resistance of the second connection terminal and the second parallel connection terminal can be made lower than the resistance of the second connection terminal when one second connection terminal is used.

[0092] (7) The liquid ejection head of the above embodiment may further include a plurality of seventh connection terminals that connect a plurality of individual electrodes corresponding to the plurality of pressure chambers included in the first pressure chamber row to the wiring board, and a plurality of eighth connection terminals that connect a plurality of individual electrodes corresponding to the plurality of pressure chambers included in the second pressure chamber row to the wiring board. According to this aspect, when only the first pressure chamber row or the second pressure chamber row is driven, unnecessary power consumption can be prevented.

[0093] (8) In the liquid ejection head of the above aspect, the width of the first connection terminal in the first direction may be larger than the width of the seventh connection terminal in the first direction. According to this embodiment, the width of the first connection terminal that commonly connects the first resistor and the second resistor to the wiring board is increased, and the cross-sectional area of ​​the first connection terminal is widened, thereby reducing the resistance value of the first connection terminal.

[0094] (9) In the liquid ejection head of the above aspect, the length of the first connection terminal in the extension direction may be longer than the length of the third connection terminal in the extension direction and may also be longer than the length of the fourth connection terminal in the extension direction. According to this embodiment, the third connection terminal and the fourth connection terminal are not unnecessarily long, and the influence of induction noise on the first connection terminal can be reduced.

[0095] (10) In the liquid ejection head of the above aspect, the at least one common electrode may include a third common electrode corresponding to both the first pressure chamber row and the second pressure chamber row, and may further include a ninth connection terminal that connects a portion of the third common electrode to the wiring substrate.

[0096] (11) 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 a combined resistance of the first detection resistor and the second detection resistor via the first connection terminal and the second connection terminal, 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.

[0097] (12) The liquid ejection device according to the above aspect may further include a drive waveform determination unit that determines drive waveforms to be applied to the individual electrodes based on the temperature acquired by the temperature acquisition unit. According to this aspect, the piezoelectric element can be driven in response to the temperature.

[0098] (13) In the liquid ejection device of the above aspect, the liquid ejection device may further include a correspondence relationship acquisition unit that acquires a first correspondence relationship representing the correspondence between temperature and resistance value when driving the first pressure chamber row and the second pressure chamber row, and a second correspondence relationship representing the correspondence between temperature and resistance value when driving either the first pressure chamber row or the second pressure chamber row, wherein the temperature acquisition unit may acquire the temperature in the vicinity of the pressure chamber based on the resistance value acquired by the resistance value acquisition unit and the first correspondence relationship when driving the first pressure chamber row and the second pressure chamber row, and may acquire the temperature in the vicinity of the pressure chamber based on the resistance value acquired by the resistance value acquisition unit and the second correspondence relationship when driving either the first pressure chamber row or the second pressure chamber row. According to this embodiment, even if either the first pressure chamber row or the second pressure chamber row is driven, the resistance value acquisition unit acquires the combined resistance of the first detection resistor and the second detection resistor, and therefore, by using either the first relationship or the second correspondence relationship, the accuracy of temperature detection can be improved.

[0099] 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]

[0100] Reference Signs List 1...liquid ejection device, 10...pressure chamber substrate, 11...partition wall, 12...pressure chamber, 12a...end, 12b...end, 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 ejection head, 130... vibration plate, 131... flexible layer, 133... protective layer, 150... piezoelectric element, 151... first electrode, 151a... end, 151b... end, 153... second electrode, 155... piezoelectric body, 157... groove, 170... wiring portion, 171... individual electrode, 172... common electrode, 172a... extension portion, 172b... extension portion, 172c... connection portion, 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, 412...second detection resistor, 415...first detection lead electrode, 416...second detection lead electrode, 417...third detection lead electrode, 418...fourth 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, Rtp...composite resistance, Rts...composite resistance, TB...conversion table, TB1...first conversion table, TB2...second conversion table

Claims

1. A liquid ejection head, a pressure chamber substrate in which a first pressure chamber row including a plurality of pressure chambers arranged in a first direction and a second pressure chamber row including a plurality of pressure chambers arranged in the first direction are arranged along a second direction intersecting the first direction; a plurality of individual electrodes provided in the first pressure chamber row and the second pressure chamber row, respectively; at least one common electrode provided in common to a plurality of pressure chambers in each of the first pressure chamber row and the second pressure chamber row; a piezoelectric element provided between each of the individual electrodes and the at least one common electrode, the piezoelectric element being driven to apply pressure to liquid within each of the pressure chambers; a first detection resistor that is formed from the same material as at least one of the plurality of individual electrodes and the at least one common electrode, and whose resistance value changes in response to the temperature of liquid inside the plurality of pressure chambers included in the first pressure chamber row; a second detection resistor that is formed from the same material as at least one of the plurality of individual electrodes and the at least one common electrode, and whose resistance value changes in response to the temperature of liquid inside the plurality of pressure chambers included in the second pressure chamber row; A wiring board; a first connection terminal for commonly connecting one end of the first detection resistor and one end of the second detection resistor to the wiring substrate; a second connection terminal for commonly connecting the other end of the first detection resistor and the other end of the second detection resistor to the wiring substrate; A liquid ejection head comprising:

2. The liquid ejection head according to claim 1 . the at least one common electrode includes a first common electrode corresponding to the first pressure chamber row and a second common electrode corresponding to the second pressure chamber row, a third connection terminal for connecting a portion of the first common electrode to the wiring substrate; a fourth connection terminal for connecting a portion of the second common electrode to the wiring substrate; Further equipped , a liquid ejection head.

3. 3. The liquid ejection head according to claim 2, a fifth connection terminal for connecting another part of the first common electrode to the wiring substrate; a sixth connection terminal for connecting another part of the second common electrode to the wiring substrate; The liquid ejection head further comprises:

4. 4. The liquid ejection head according to claim 3, a distance between the first connection terminal and the third connection terminal in the first direction is shorter than a distance between the first connection terminal and the fourth connection terminal in the first direction; a distance between the second connection terminal and the fifth connection terminal in the first direction is longer than a distance between the second connection terminal and the sixth connection terminal in the first direction; Liquid ejection head.

5. 3. The liquid ejection head according to claim 2, a width of the first connection terminal in the first direction is greater than a width of the third connection terminal in the first direction; Liquid ejection head.

6. 3. The liquid ejection head according to claim 2, a first parallel connection terminal connected in parallel to the first connection terminal and commonly connecting one end of the first detection resistor and one end of the second detection resistor to the wiring board; a second parallel connection terminal connected in parallel to the second connection terminal and commonly connecting the other end of the first detection resistor and the other end of the second detection resistor to the wiring board; Further comprising: Liquid ejection head.

7. 2. The liquid ejection head according to claim 1, a plurality of seventh connection terminals that connect a plurality of individual electrodes corresponding to the plurality of pressure chambers included in the first pressure chamber row to the wiring substrate, respectively; a plurality of eighth connection terminals that connect a plurality of individual electrodes corresponding to the plurality of pressure chambers included in the second pressure chamber row to the wiring substrate, respectively; Further comprising: Liquid ejection head.

8. 8. The liquid ejection head according to claim 7, The width of the first connection terminal in the first direction is larger than the width of the seventh connection terminal in the first direction. Liquid ejection head.

9. 3. The liquid ejection head according to claim 2, a length of the first connection terminal in the extension direction is longer than a length of the third connection terminal in the extension direction and is longer than a length of the fourth connection terminal in the extension direction; Liquid ejection head.

10. The liquid ejection head according to claim 1 . the at least one common electrode includes a third common electrode corresponding to both the first pressure chamber row and the second pressure chamber row, a ninth connection terminal for connecting a portion of the third common electrode to the wiring substrate; Liquid ejection head.

11. A liquid ejection device, A liquid ejection head according to any one of claims 1 to 10, a resistance value acquiring unit that acquires a resistance value of a combined resistance of the first detection resistor and the second detection resistor via the first connection terminal and the second connection terminal; 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:

12. The liquid ejection device according to claim 11, 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; Further comprising: Liquid discharge device.

13. The liquid ejection device according to claim 11, a first correspondence relationship representing a correspondence between a temperature and a resistance value when the first pressure chamber row and the second pressure chamber row are driven; a correspondence relationship acquisition unit that acquires a second correspondence relationship that represents a correspondence between a temperature and a resistance value when either one of the first pressure chamber row or the second pressure chamber row is driven; Further equipped with The temperature acquisition unit is when the first pressure chamber row and the second pressure chamber row are driven, a temperature in the vicinity of the pressure chamber is acquired based on the resistance value acquired by the resistance value acquisition unit and the first correspondence relationship; when driving either the first pressure chamber row or the second pressure chamber row, the resistance value acquisition unit acquires a temperature in the vicinity of the pressure chamber based on the acquired resistance value and the second correspondence relationship. Liquid discharge device.

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