Liquid discharge head and liquid discharge apparatus

Abstract

The present application provides a liquid ejection head and a liquid ejection device. The liquid ejection head includes a first pressure chamber extending in a first direction and applying pressure to a liquid, a second pressure chamber extending in the first direction and applying pressure to the liquid, a nozzle flow passage extending in the first direction and communicating with a nozzle ejecting the liquid, a first communication flow passage extending in a second direction intersecting the first direction and communicating the first pressure chamber with the nozzle flow passage, a second communication flow passage extending in the second direction and communicating the second pressure chamber with the nozzle flow passage, a wall surface of the nozzle flow passage including a first wall surface extending in the first direction and provided with the nozzle and a second wall surface extending in the first direction and opposite to the first wall surface, a wall surface of the first communication flow passage including a third wall surface extending in the second direction and farthest from the nozzle in the first direction and a fourth wall surface extending in the second direction and opposite to the third wall surface, and a fifth wall surface extending in a third direction between the first direction and the second direction provided between the second wall surface and the fourth wall surface.

Description

Technical Field

[0001] This invention relates to a liquid ejector head and a liquid ejection device. Background Technology

[0002] A technology relating to a liquid ejector head that causes liquid in a pressure chamber to be ejected from a nozzle, as described in Patent Document 1, has been known for a long time.

[0003] However, in existing technologies, it is possible for air bubbles to become trapped in the flow path from the pressure chamber to the nozzle, making it difficult for the liquid to be ejected from the nozzle, resulting in ejection abnormalities.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2017-013390 Summary of the Invention

[0005] To address the above problems, the preferred embodiment of the present invention involves a liquid ejector head characterized by comprising: a first pressure chamber extending in a first direction and applying pressure to a liquid; a second pressure chamber extending in the first direction and applying pressure to the liquid; a nozzle channel extending in the first direction and communicating with a nozzle for ejecting liquid; a first connecting channel extending in a second direction intersecting the first direction and communicating between the first pressure chamber and the nozzle channel; and a second connecting channel extending in the second direction and communicating between the second pressure chamber and the nozzle channel, wherein the wall surface of the nozzle channel... The first communicating channel includes a first wall and a second wall. The first wall extends in a first direction and is provided with the nozzle. The second wall extends in the first direction and is located on the side opposite to the first wall. The walls of the first communicating channel include a third wall and a fourth wall. The third wall extends in a second direction and is furthest from the nozzle in the first direction. The fourth wall extends in the second direction and is located on the side opposite to the third wall. A fifth wall is provided between the second wall and the fourth wall. The fifth wall extends upward in a third direction between the first direction and the second direction.

[0006] The liquid ejection device according to a preferred embodiment of the present invention is characterized by comprising: a first pressure chamber extending in a first direction and applying pressure to a liquid; a second pressure chamber extending in the first direction and applying pressure to the liquid; a nozzle channel extending in the first direction and communicating with a nozzle for ejecting liquid; a first connecting channel extending in a second direction intersecting the first direction and communicating between the first pressure chamber and the nozzle channel; and a second connecting channel extending in the second direction and communicating between the second pressure chamber and the nozzle channel, wherein the wall of the nozzle channel includes a first wall. The first wall extends in the first direction and is provided with the nozzle. The second wall extends in the first direction and is located on the side opposite to the first wall. The walls of the first communicating channel include a third wall and a fourth wall. The third wall extends in the second direction and is furthest from the nozzle in the first direction. The fourth wall extends in the second direction and is located on the side opposite to the third wall. A fifth wall is provided between the second wall and the fourth wall. The fifth wall extends upward in a third direction between the first direction and the second direction. Attached Figure Description

[0007] Figure 1 This is a structural diagram illustrating an example of a liquid ejection device 100 according to an embodiment of the present invention.

[0008] Figure 2 An exploded perspective view showing an example of the structure of a liquid ejector head 1.

[0009] Figure 3 A cross-sectional view showing an example of the structure of a liquid ejector head 1.

[0010] Figure 4 This is a cross-sectional view showing an example of the structure of a piezoelectric element PZq.

[0011] Figure 5 A cross-sectional view showing an example of the structure of a liquid ejector head 1.

[0012] Figure 6 An illustrative diagram showing an example of the ink flow rate in the circulating channel RJ.

[0013] Figure 7 A cross-sectional view illustrating an example of the structure of the liquid ejector head 1Z involved in the reference example.

[0014] Figure 8 An illustrative diagram illustrating an example of the ink flow rate in a circulating channel involved in the reference example.

[0015] Figure 9 A cross-sectional view showing an example of the structure of the liquid ejector head 1A involved in Modified Example 1.

[0016] Figure 10 An exploded perspective view showing an example of the structure of the liquid ejector head 1B involved in Modified Example 2.

[0017] Figure 11 A plan view showing an example of the structure of the liquid ejector head 1B involved in Modified Example 2.

[0018] Figure 12 A cross-sectional view showing an example of the structure of the liquid ejector head 1B involved in Modified Example 2.

[0019] Figure 13 A cross-sectional view showing an example of the structure of the liquid ejector head 1B involved in Modified Example 2.

[0020] Figure 14 A cross-sectional view showing an example of the structure of the liquid ejector head 1B involved in Modified Example 2.

[0021] Figure 15 A cross-sectional view showing an example of the structure of the liquid ejector head 1B involved in Modified Example 2.

[0022] Figure 16 This is a structural diagram illustrating an example of the liquid ejection device 100C involved in Modification Example 3. Detailed Implementation

[0023] Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings. However, in the drawings, the dimensions and scales of the various parts are appropriately different from the actual figures. Furthermore, since the embodiments described below are preferred examples of the present invention, various technically preferred limitations are imposed; however, unless otherwise specified in the following description, the scope of the present invention is not limited to these embodiments.

[0024] A. Implementation Method

[0025] The following is for reference Figure 1 The liquid ejection device 100 according to this embodiment will be described.

[0026] 1. Overview of the liquid ejection device

[0027] Figure 1This is an explanatory diagram illustrating an example of the liquid ejection apparatus 100 according to this embodiment. The liquid ejection apparatus 100 according to this embodiment is an inkjet printing apparatus that ejects ink onto a medium PP. Although the medium PP is typically printing paper, any printing object such as resin film or fabric can also be used as the medium PP.

[0028] like Figure 1 As illustrated, the liquid dispensing device 100 includes a liquid container 93 for storing ink. The liquid container 93 can be, for example, a cartridge that is detachable from the liquid dispensing device 100, a bag-shaped ink pouch formed of a flexible film, or an ink canister capable of being refilled. Various inks of different colors are stored in the liquid container 93.

[0029] like Figure 1 As illustrated, the liquid ejection device 100 includes a control device 90, a moving mechanism 91, a conveying mechanism 92, and a circulation mechanism 94.

[0030] The control device 90 includes processing circuits such as a CPU or FPGA, and storage circuits such as semiconductor memory, and controls various elements of the liquid dispensing device 100. Here, CPU is short for Central Processing Unit, and FPGA is short for Field Programmable Gate Array.

[0031] Furthermore, under the control of the control device 90, the moving mechanism 91 transports the medium PP in the +Y direction. Additionally, in the following text, the +Y direction and the opposite direction, the -Y direction, will be collectively referred to as the Y-axis direction.

[0032] Furthermore, under the control of the control device 90, the conveying mechanism 92 causes the plurality of liquid nozzles 1 to move back and forth in the +X direction and the opposite direction, i.e., the -X direction. Hereinafter, the +X direction and the -X direction will be collectively referred to as the X-axis direction. Here, the +X direction is the direction intersecting the +Y direction. Typically, the +X direction is the direction orthogonal to the +Y direction. The conveying mechanism 92 includes a housing 921 for storing the plurality of liquid nozzles 1 and a seamless strap 922 for fixing the housing 921. Alternatively, the liquid container 93 can also be stored together with the liquid nozzles 1 in the housing 921.

[0033] Furthermore, under the control of the control device 90, the circulation mechanism 94 supplies the ink stored in the liquid container 93 to the supply channel RB1 provided in the liquid nozzle 1. Additionally, under the control of the control device 90, the circulation mechanism 94 recovers the ink stored in the discharge channel RB2 provided in the liquid nozzle 1 and returns the recovered ink to the supply channel RB1. Furthermore, the supply channel RB1 and the discharge channel RB2 are utilized... Figure 3 This will be described in the following text.

[0034] like Figure 1 As illustrated, in the liquid ejector head 1, a drive signal Com for driving the liquid ejector head 1 and a control signal SI for controlling the liquid ejector head 1 are supplied from the control device 90. Then, under the control of the control signal SI, the liquid ejector head 1 is driven by the drive signal Com, causing ink to be ejected from some or all of the M nozzles N provided on the liquid ejector head 1 in the +Z direction. Here, the value M is a natural number greater than or equal to 1. Furthermore, the +Z direction is a direction intersecting the +X and +Y directions. Typically, the +Z direction is a direction orthogonal to the +X and +Y directions. In the following text, the +Z direction and the direction opposite to the +Z direction, i.e., the -Z direction, are sometimes collectively referred to as the Z-axis direction. Additionally, for the nozzles N, a drive signal Com for driving the liquid ejector head 1 and a control signal SI for controlling the liquid ejector head 1 are supplied from the control device 90. Figure 2 as well as Figure 3 This will be described in the following text.

[0035] The liquid ejector head 1 is linked with the transport of the medium PP implemented by the moving mechanism 91 and the reciprocating movement of the liquid ejector head 1 implemented by the transport mechanism 92, so that ink is ejected from part or all of the M nozzles N, and the ejected ink is sprayed onto the surface of the medium PP, thereby forming the desired image on the surface of the medium PP.

[0036] 2. Overview of the liquid nozzle

[0037] The following is for reference Figures 2 to 4 The general outline of liquid ejector head 1 will be described.

[0038] in addition, Figure 2 This is an exploded perspective view of liquid ejector head 1. Figure 3 for Figure 2 A sectional view along line III-III.

[0039] like Figure 2 as well as Figure 3 As illustrated, the liquid ejector head 1 includes a nozzle substrate 60, a plastic sheet 61 and a plastic sheet 62, a connecting plate 2, a pressure chamber substrate 3, a vibrating plate 4, a storage chamber forming substrate 5, and a wiring substrate 8.

[0040] like Figure 2 As illustrated, the nozzle substrate 60 is a plate-shaped component that is elongated in the Y-axis direction and extends substantially parallel to the XY plane, and has M nozzles N formed thereon. Here, "substantially parallel" means, in addition to the case of perfect parallelism, also includes the concept of parallelism if errors are taken into account. The nozzle substrate 60 is manufactured, for example, by processing a single-crystal silicon substrate using semiconductor manufacturing techniques such as etching. However, known materials and manufacturing methods can be used arbitrarily in the manufacture of the nozzle substrate 60. Furthermore, the nozzles N are through holes provided on the nozzle substrate 60. In this embodiment, as an example, it is envisioned that the M nozzles N in the nozzle substrate 60 are arranged in a nozzle row Ln extending in the Y-axis direction.

[0041] like Figure 2 as well as Figure 3 As illustrated, a connecting plate 2 is provided on the -Z side of the nozzle substrate 60. The connecting plate 2 is a plate-shaped component that is elongated in the Y-axis direction and extends in a manner substantially parallel to the XY plane, and has ink flow channels formed thereon.

[0042] Specifically, a supply channel RA1 and a discharge channel RA2 are formed on the connecting plate 2. The supply channel RA1 is configured to communicate with the supply channel RB1 (described later) and extend in the Y-axis direction. Furthermore, the discharge channel RA2 is configured to communicate with the discharge channel RB2 (described later) and extend in the -X direction along the Y-axis direction when viewed from the supply channel RA1.

[0043] Furthermore, the connecting plate 2 has M connecting channels RK1 corresponding to each of the M nozzles N, M connecting channels RK2 corresponding to each of the M nozzles N, M connecting channels RR1 corresponding to each of the M nozzles N, M connecting channels RR2 corresponding to each of the M nozzles N, and M nozzle channels RN corresponding to each of the M nozzles N. Connecting channels RK1 are configured to communicate with the supply channel RA1 and extend along the Z-axis in the -X direction when viewed from the supply channel RA1. Connecting channels RR1 are configured to extend along the Z-axis in the -X direction when viewed from the connecting channels RK1. Connecting channels RK2 are configured to communicate with the discharge channel RA2 and extend along the Z-axis in the +X direction when viewed from the discharge channel RA2. Furthermore, the connecting channel RR2 is configured to extend along the Z-axis direction in the +X direction when viewed from the connecting channel RK2 and in the -X direction when viewed from the connecting channel RR1. Additionally, the nozzle channel RN is configured to connect the connecting channels RR1 and RR2, and extend along the X-axis direction in the -X direction when viewed from the connecting channel RR1 and in the +X direction when viewed from the connecting channel RR2. The nozzle channel RN is connected to the nozzle N corresponding to it.

[0044] Furthermore, the connecting plate 2 can be manufactured, for example, by processing a single-crystal silicon substrate using semiconductor manufacturing technology. However, in the manufacture of the connecting plate 2, any known materials and manufacturing methods can be used.

[0045] like Figure 2 as well as Figure 3 As illustrated, a pressure chamber substrate 3 is provided on the -Z side of the connecting plate 2. The pressure chamber substrate 3 is a plate-shaped component that is elongated in the Y-axis direction and extends substantially parallel to the XY plane, and has ink flow channels formed thereon.

[0046] Specifically, M pressure chambers CB1 and M pressure chambers CB2, each corresponding to one of the M nozzles N, are formed on the pressure chamber substrate 3. The pressure chambers CB1 are configured to connect the connecting flow channel RK1 and the connecting flow channel RR1, and when viewed from the Z-axis direction, the +X side end of the connecting flow channel RK1 is connected to the -X side end of the connecting flow channel RR1 and extends in the X-axis direction. Similarly, the pressure chambers CB2 are configured to connect the connecting flow channel RK2 and the connecting flow channel RR2, and when viewed from the Z-axis direction, the -X side end of the connecting flow channel RK2 is connected to the +X side end of the connecting flow channel RR2 and extends in the X-axis direction.

[0047] Furthermore, the pressure chamber substrate 3 can be manufactured, for example, by processing a single-crystal silicon substrate using semiconductor manufacturing technology. However, in the manufacture of the pressure chamber substrate 3, any known materials and manufacturing methods can be used.

[0048] Furthermore, in the following text, the ink channel that connects the supply channel RA1 and the discharge channel RA2 will be referred to as the circulation channel RJ. That is, the supply channel RA1 and the discharge channel RA2 are connected by M circulation channels RJ corresponding one-to-one with M nozzles N. As described above, each circulation channel RJ includes a connecting channel RK1 connected to the supply channel RA1, a pressure chamber CB1 connected to the connecting channel RK1, a connecting channel RR1 connected to the pressure chamber CB1, a nozzle channel RN connected to the connecting channel RR1, a connecting channel RR2 connected to the nozzle channel RN, a pressure chamber CB2 connected to the connecting channel RR2, and a connecting channel RK2 connected to both the pressure chamber CB2 and the discharge channel RA2.

[0049] like Figure 2 as well as Figure 3 As illustrated, a vibrating plate 4 is provided on the -Z side of the pressure chamber substrate 3. The vibrating plate 4 is a plate-shaped component that is elongated in the Y-axis direction and extends in a manner substantially parallel to the XY plane, and is a component capable of elastic vibration.

[0050] like Figure 2 as well as Figure 3 As illustrated, M piezoelectric elements PZ1, corresponding to M pressure chambers CB1, and M piezoelectric elements PZ2, corresponding to M pressure chambers CB21, are provided on the -Z side of the vibrating plate 4. In the following text, piezoelectric elements PZ1 and PZ2 are collectively referred to as piezoelectric element PZq. Piezoelectric element PZq is a passive element that deforms according to the potential change of the driving signal Com. In other words, piezoelectric element PZq is an example of an energy conversion element that converts the electrical energy of the driving signal Com into kinetic energy. Furthermore, in the following text, the suffix "q" is sometimes added to the symbol representing the structural element or signal corresponding to piezoelectric element PZq in the liquid ejector head 1.

[0051] Figure 4 This is an enlarged cross-sectional view of the vicinity of the piezoelectric element PZq.

[0052] like Figure 4As illustrated, the piezoelectric element PZq is a laminate in which a piezoelectric body ZMq is positioned between a lower electrode ZDq supplied with a predetermined reference potential VBS and an upper electrode ZUq supplied with a drive signal Com. The piezoelectric element PZq is, for example, the portion where the lower electrode ZDq, the upper electrode ZUq, and the piezoelectric body ZMq overlap when viewed from the -Z direction. Furthermore, a pressure chamber CBq is provided in the +Z direction of the piezoelectric element PZq.

[0053] As described above, the piezoelectric element PZq is driven to deform according to the potential change of the drive signal Com. The vibrating plate 4 vibrates in a manner linked to the deformation of the piezoelectric element PZq. When the vibrating plate 4 vibrates, the pressure inside the pressure chamber CBq changes. Then, due to the pressure change inside the pressure chamber CBq, the ink filled inside the pressure chamber CBq is ejected from the nozzle N through the connecting channel RRq and the nozzle channel RN.

[0054] like Figure 2 as well as Figure 3 As illustrated, a wiring board 8 is mounted on the -Z side surface of the vibrating plate 4. The wiring board 8 is a component for electrically connecting the control device 90 and the liquid nozzle 1. As the wiring board 8, a flexible wiring board such as an FPC or FFC is preferably used, for example. Here, FPC is short for Flexible Printed Circuit, and FFC is short for Flexible Flat Cable. A drive circuit 81 is mounted on the wiring board 8. The drive circuit 81 is a circuit that switches whether to supply a drive signal Com to the piezoelectric element PZq under the control of the control signal SI. Figure 4 As illustrated, the drive circuit 81 supplies a drive signal Com to the upper electrode ZUq of the piezoelectric element PZq via wiring 810.

[0055] Furthermore, in the following text, the drive signal Com supplied to the piezoelectric element PZ1 will sometimes be referred to as drive signal Com1, and the drive signal Com supplied to the piezoelectric element PZ2 will be referred to as drive signal Com2. In this embodiment, it is envisioned that when ink is ejected from the nozzle N, the waveforms of the drive signal Com1 supplied by the drive circuit 81 to the piezoelectric element PZ1 corresponding to the nozzle N and the drive signal Com2 supplied by the drive circuit 81 to the piezoelectric element PZ2 corresponding to the nozzle N are substantially the same. Here, "substantially the same" means, in addition to the case of being completely identical, also includes the concept of being considered identical if errors are taken into account.

[0056] like Figure 2 as well as Figure 3As illustrated, a reservoir forming substrate 5 is provided on the -Z side of the connecting plate 2. The reservoir forming substrate 5 is a long and narrow component in the Y-axis direction, and an ink flow channel is formed thereon.

[0057] Specifically, a supply channel RB1 and a discharge channel RB2 are formed on the storage chamber forming substrate 5. The supply channel RB1 is configured to communicate with the supply channel RA1 and extend along the Y-axis in the -Z direction when viewed from the supply channel RA1. Furthermore, the discharge channel RB2 is configured to communicate with the discharge channel RA2 and extend in the -Z direction when viewed from the discharge channel RA2, and along the Y-axis in the -X direction when viewed from the supply channel RB1.

[0058] Furthermore, the substrate 5 forming the storage chamber is provided with an inlet 51 communicating with the supply channel RB1 and an outlet 52 communicating with the discharge channel RB2. Moreover, ink is supplied from the liquid container 93 to the supply channel RB1 via the inlet 51. In addition, the ink stored in the discharge channel RB2 is recovered via the outlet 52.

[0059] In addition, an opening 50 is provided on the storage chamber forming substrate 5. A pressure chamber substrate 3, a vibrating plate 4, and a wiring substrate 8 are provided inside the opening 50.

[0060] Furthermore, the storage chamber forming substrate 5 is formed, for example, by injection molding of a resin material. However, known materials and manufacturing methods can be used arbitrarily in the manufacture of the storage chamber forming substrate 5.

[0061] In this embodiment, ink supplied from liquid container 93 to inlet 51 flows into supply channel RA1 via supply channel RB1. Then, a portion of the ink flowing into supply channel RA1 flows into pressure chamber CB1 via connecting channel RK1. Furthermore, a portion of the ink flowing into pressure chamber CB1 flows into pressure chamber CB2 via connecting channel RR1, nozzle channel RN, and connecting channel RR2. Then, a portion of the ink flowing into pressure chamber CB2 is discharged from outlet 52 via connecting channel RK2, discharge channel RA2, and discharge channel RB2.

[0062] Furthermore, when piezoelectric element PZ1 is driven by drive signal Com1, a portion of the ink filled inside pressure chamber CB1 is ejected from nozzle N via connecting flow channel RR1 and nozzle flow channel RN. Additionally, when piezoelectric element PZ2 is driven by drive signal Com2, a portion of the ink filled inside pressure chamber CB2 is ejected from nozzle N via connecting flow channel RR2 and nozzle flow channel RN.

[0063] like Figure 2as well as Figure 3 As illustrated, a plastic sheet 61 is provided on the +Z side surface of the connecting plate 2 to block the supply channel RA1 and the connecting channel RK1. The plastic sheet 61 is formed of an elastic material and absorbs pressure fluctuations of the ink in the supply channel RA1 and the connecting channel RK1. Furthermore, a plastic sheet 62 is provided on the +Z side surface of the connecting plate 2 to block the discharge channel RA2 and the connecting channel RK2. The plastic sheet 62 is formed of an elastic material and absorbs pressure fluctuations of the ink in the discharge channel RA2 and the connecting channel RK2.

[0064] As described above, the liquid ejector head 1 of this embodiment circulates ink from the supply channel RA1 through the circulation channel RJ to the discharge channel RA2. Therefore, in this embodiment, even when there is a period in which ink inside the pressure chamber CBq is not ejected from the nozzle N, the ink retention state inside the pressure chamber CBq and the nozzle channel RN can be prevented from continuing. Therefore, in this embodiment, even when there is a period in which ink inside the pressure chamber CBq is not ejected from the nozzle N, the thickening of the ink inside the pressure chamber CBq can be suppressed, thereby preventing the occurrence of ejection abnormalities caused by ink thickening that prevent the ink from being ejected from the nozzle N.

[0065] Furthermore, the liquid ejector head 1 according to this embodiment can eject ink filled inside pressure chamber CB1 and ink filled inside pressure chamber CB2 from nozzle N. Therefore, in the liquid ejector head 1 according to this embodiment, for example, compared to the method of ejecting only ink filled inside one pressure chamber CBq from nozzle N, the amount of ink ejected from nozzle N can be increased.

[0066] 3. The shape of the circulating flow channel,

[0067] The following is for reference Figure 5 as well as Figure 6 The shape of the circulating flow channel RJ is described.

[0068] Figure 5 This is a cross-sectional view of the pressure chamber CB1, connecting channel RR1, nozzle channel RN, connecting channel RR2, and pressure chamber CB2 in the circulating channel RJ.

[0069] like Figure 5As illustrated, the nozzle flow channel RN, when viewed from the Y-axis direction, has a wall surface HNa on the +Z side and a wall surface HNb on the -Z side. Here, wall surface HNa is the wall surface of the nozzle flow channel RN on which the nozzle N is formed, and it is a wall surface that extends along the X-axis direction when viewed from the Y-axis direction. Furthermore, wall surface HNb is the wall surface on the side opposite to wall surface HNa of the two walls constituting the nozzle flow channel RN when viewed from the Y-axis direction, and it is a wall surface that extends along the X-axis direction when viewed from the Y-axis direction.

[0070] Furthermore, the connecting channel RR1, when viewed from the Y-axis direction, has a wall surface HRa1 on the +X side and a wall surface HRb1 on the -X side. Here, wall surface HRa1 is the wall surface that is furthest from the nozzle N in the X-axis direction among the walls constituting the connecting channel RR1, and is a wall surface that extends along the Z-axis direction when viewed from the Y-axis direction. In addition, in this embodiment, "the distance between one object and another object" refers to the shortest distance between one object and another object. Furthermore, wall surface HRb1 is the wall surface opposite to wall surface HRa1 among the two walls constituting the connecting channel RR1 and extending along the Z-axis direction when viewed from the Y-axis direction.

[0071] Furthermore, the connecting channel RR2, when viewed from the Y-axis direction, has a wall surface HRa2 on the -X side and a wall surface HRb2 on the +X side. Here, wall surface HRa2 is the wall surface that is furthest from the nozzle N in the X-axis direction among the walls constituting the connecting channel RR2, and it is a wall surface that extends along the Z-axis direction when viewed from the Y-axis direction. Furthermore, wall surface HRb2 is the wall surface opposite to wall surface HRa2 among the two walls constituting the connecting channel RR2 that extend along the Z-axis direction when viewed from the Y-axis direction.

[0072] Furthermore, the pressure chamber CB1 has a wall HC1 when viewed from the Y-axis direction. Here, the wall HC1 is the +Z side wall of the two walls that constitute the pressure chamber CB1 and extend along the X-axis direction when viewed from the Y-axis direction.

[0073] Furthermore, the pressure chamber CB2 has a wall HC2 when viewed from the Y-axis direction. Here, the wall HC2 is the +Z side wall of the two walls that constitute the pressure chamber CB2 and extend along the X-axis direction when viewed from the Y-axis direction.

[0074] Furthermore, in this embodiment, the nozzle N is positioned approximately at the center of the nozzle flow channel RN. For example, the distance from the nozzle N to the wall surface HRb1 in the X-axis direction can also be approximately the same as the distance from the nozzle N to the wall surface HRb2 in the X-axis direction. Here, "approximately at the center" means, in addition to the case where it is strictly at the center, it also includes the case where it is considered to be at the center if errors are taken into account.

[0075] like Figure 5 As illustrated, an inclined surface HD1 is provided between wall surface HNb and wall surface HRb1, the inclined surface HD1 extending along the W1 direction when viewed from the Y-axis direction. More specifically, the inclined surface HD1 is configured to connect wall surface HNb and wall surface HRb1.

[0076] Here, the W1 direction refers to the direction between the +X direction and the -Z direction. Furthermore, in this embodiment, the inclined surface HD1 is provided such that the angle θ11 between the W1 direction and the +X direction is greater than 30 degrees and less than 60 degrees, and the angle θ12 between the W1 direction and the -Z direction is greater than 30 degrees and less than 60 degrees. In other words, in this embodiment, the angle θ11 between the normal direction of the inclined surface HD1 and the normal direction of the wall HNb is greater than 30 degrees and less than 60 degrees, and the angle θ12 between the normal direction of the inclined surface HD1 and the normal direction of the wall HRb1 is greater than 30 degrees and less than 60 degrees. However, angle θ11 only needs to be greater than 20 degrees and less than 80 degrees, and angle θ12 only needs to be greater than 10 degrees and less than 70 degrees. Alternatively, angles θ11 and θ12 can be set to approximately the same angle, for example, 45 degrees.

[0077] like Figure 5 As illustrated, an inclined surface HD2 is provided between wall surface HNb and wall surface HRb2, which extends along the W2 direction when viewed from the Y-axis direction. More specifically, the inclined surface HD2 is configured to connect wall surface HNb and wall surface HRb2.

[0078] Here, the W2 direction refers to the direction between the -X direction and the -Z direction. Furthermore, in this embodiment, the inclined surface HD2 is provided such that the angle θ21 between the W2 direction and the -X direction is greater than 30 degrees and less than 60 degrees, and the angle θ22 between the W2 direction and the -Z direction is greater than 30 degrees and less than 60 degrees. In other words, in this embodiment, the angle θ21 between the normal direction of the inclined surface HD2 and the normal direction of the wall HNb is greater than 30 degrees and less than 60 degrees, and the angle θ22 between the normal direction of the inclined surface HD2 and the normal direction of the wall HRb2 is greater than 30 degrees and less than 60 degrees. However, angle θ21 only needs to be greater than 20 degrees and less than 80 degrees, and angle θ22 only needs to be greater than 10 degrees and less than 70 degrees. Alternatively, angles θ21 and θ22 can be set to approximately the same angle, for example, 45 degrees. Furthermore, angles θ21 and θ11 can also be set to approximately the same angle. Alternatively, angles θ22 and θ12 can be set to approximately the same angle.

[0079] Furthermore, wall surface HNa is connected to wall surface HRa1, and wall surface HNa is connected to wall surface HRa2. In other words, no inclined surface is provided between wall surface HNa and wall surface HRa1, and no inclined surface is provided between wall surface HNa and wall surface HRa2.

[0080] Furthermore, wall surface HRa1 is connected to wall surface HC1, and wall surface HRa2 is connected to wall surface HC2. In other words, no inclined surface is provided between wall surface HRa1 and wall surface HC1, and no inclined surface is provided between wall surface HRa2 and wall surface HC2.

[0081] Figure 6 This is an explanatory diagram used to illustrate an example where, in the case where the piezoelectric element PZq is not driven by the drive signal Com and the ink is not ejected from the nozzle N, the ink flows from the connecting channel RR1 through the nozzle channel RN to the connecting channel RR2, representing an example of the ink flow rate in the circulating channel RJ. Additionally, in Figure 6 In the diagram, region Ar1 is the region where the ink flow rate is above speed V1, region Ar2 is the region where the ink flow rate is above speed V2 but below speed V1, region Ar3 is the region where the ink flow rate is above speed V3 but below speed V2, and region Ar4 is the region where the ink flow rate is below speed V3. Here, it is assumed that speeds V1 to V3 satisfy "0 ≤ V3 < V2 < V1".

[0082] like Figure 6 As shown, in this embodiment, when viewed from the Y-axis direction, the ink flow rate is faster near the center of the circulation channel RJ compared to the vicinity of the wall of the circulation channel RJ.

[0083] Specifically, in this embodiment, the area near the center of the circulation channel RJ is designated as region Ar1, the area near the wall of the circulation channel RJ is designated as region Ar3, and the area between region Ar1 and region Ar3 is designated as region Ar2. Furthermore, in this embodiment, region Ar4 appears near the junction of wall HNa and wall HRa1, and near the junction of wall HNa and wall HRa2.

[0084] 4. Reference Example

[0085] To clarify the effects of this embodiment, the following will refer to... Figure 7 as well as Figure 8 The liquid ejector head 1Z involved in the reference example will be explained.

[0086] Figure 7 This is a cross-sectional view of the circulation channel in the liquid nozzle 1Z of the reference example, viewed from the Y-axis direction.

[0087] like Figure 7 As shown, except for the point that wall surface HNb is connected to wall surface HRb1 and no inclined surface HD1 is provided between wall surface HNb and wall surface HRb1, and the point that wall surface HNb is connected to wall surface HRb2 and no inclined surface HD2 is provided between wall surface HNb and wall surface HRb2, the liquid nozzle 1Z is constructed in the same manner as the liquid nozzle 1 according to the embodiment. That is, except for the point that corner portion Ed1 is formed at the connection between wall surface HNb and wall surface HRb1, and the point that corner portion Ed2 is formed at the connection between wall surface HNb and wall surface HRb2, the liquid nozzle 1Z according to the reference example is constructed in the same manner as the liquid nozzle 1 according to the embodiment.

[0088] Figure 8 This is an explanatory diagram used to illustrate an example, namely, in the liquid ejector head 1Z of the reference example, where the piezoelectric element PZq is not driven by the drive signal Com and the ink is not ejected from the nozzle N, an example of the flow rate of ink in the circulating channel when the ink flows from the connecting channel RR1 through the nozzle channel RN to the connecting channel RR2.

[0089] like Figure 8As shown, in the liquid ejector head 1Z of the reference example, ink flow is obstructed near corners Ed1 and Ed2. Therefore, in the liquid ejector head 1Z of the reference example, compared to the liquid ejector head 1 of the embodiment, the ink flow rate decreases near corners Ed1 and Ed2. Therefore, in the liquid ejector head 1Z of the reference example, regions Ar4 will appear near corners Ed1 and Ed2. More specifically, in the liquid ejector head 1Z of the reference example, in addition to the areas near the junctions of wall surface HNa and wall surface HRa1, and the junctions of wall surface HNa and wall surface HRa2, regions Ar4 will also appear near wall surface HRb1, wall surface HNb, and wall surface HRb2.

[0090] Therefore, in the liquid ejector head 1Z described in the reference example, compared to the liquid ejector head 1 described in the embodiment, air bubbles are more likely to remain near the wall surface HRb1, the wall surface HNb, and the wall surface HRb2. When air bubbles remain in the circulating flow channels such as the nozzle flow channel RN, even if the piezoelectric element PZq is driven by the drive signal Com, the pressure that the piezoelectric element PZq wants to expel ink is absorbed by the air bubbles, resulting in a so-called ejection abnormality where ink is difficult to eject from the nozzle N. Moreover, in the event of an ejection abnormality, the image quality of the image formed on the medium PP will decrease. In particular, when air bubbles remain in the circulating flow channel RJ between the piezoelectric element PZq and the nozzle N, it becomes difficult for the ink driven by the piezoelectric element PZq to be ejected from the nozzle N. In other words, when air bubbles remain near the wall surface HNb on the +X side compared to the nozzle N or near the wall surface HRb1, the possibility of ejection abnormalities occurring in the ink ejection driven by the piezoelectric element PZ1 is higher. Furthermore, when air bubbles are trapped near the wall surface HNb, closer to the -X side than the nozzle N, or near the wall surface HRb2, there is a higher probability of ejection abnormalities occurring during ink ejection driven by the piezoelectric element PZ2.

[0091] In contrast, in the liquid ejector head 1 of this embodiment, an inclined surface HD1 is provided between the wall surface HNb and the wall surface HRb1, and an inclined surface HD2 is provided between the wall surface HNb and the wall surface HRb2. Therefore, in the liquid ejector head 1 of this embodiment, compared with the liquid ejector head 1Z of the reference example, the decrease in ink flow rate near the wall surface HRb1, near the wall surface HNb, and near the wall surface HRb2 can be suppressed. Therefore, in the liquid ejector head 1 of this embodiment, compared with the liquid ejector head 1Z of the reference example, the possibility of air bubbles remaining in the circulating flow channels RJ such as the nozzle flow channel RN can be reduced, thereby reducing the possibility of ejection abnormalities due to air bubbles. As a result, in the liquid ejector head 1 of this embodiment, compared with the liquid ejector head 1Z of the reference example, a higher quality image can be formed for the medium PP.

[0092] 5. Summary of Implementation Methods

[0093] As explained above, the liquid ejector head 1 according to this embodiment is characterized by comprising: a pressure chamber CB1 extending in the +X direction and applying pressure to the ink; a pressure chamber CB2 extending in the +X direction and applying pressure to the ink; a nozzle flow channel RN extending in the +X direction and communicating with a nozzle N for ejecting ink; a connecting flow channel RR1 extending in the -Z direction intersecting the +X direction and communicating between the pressure chamber CB1 and the nozzle flow channel RN; and a connecting flow channel RR2 extending in the -Z direction and communicating between the pressure chamber CB2 and the nozzle flow channel RN, wherein the wall of the nozzle flow channel RN is covered with... The system includes wall surfaces HNa and HNb. Wall surface HNa extends in the +X direction and is provided with nozzle N. Wall surface HNb extends in the +X direction and is located on the opposite side of wall surface HNa. The wall surface of the flow channel RR1 includes wall surface HRa1 and wall surface HRb1. Wall surface HRa1 extends in the -Z direction and is farthest from nozzle N in the +X direction. Wall surface HRb1 extends in the -Z direction and is located on the opposite side of wall surface HRa1. An inclined surface HD1 is provided between wall surface HNb and wall surface HRb1. The inclined surface HD1 extends in the W1 direction, which is between the +X direction and the -Z direction.

[0094] In other words, the liquid ejector head 1 according to this embodiment has an inclined surface HD1 provided between the wall surface HNb and the wall surface HRb1. Therefore, compared with a method where the inclined surface HD1 is not provided between the wall surface HNb and the wall surface HRb1, the flow of ink from the connecting flow channel RR1 to the nozzle flow channel RN and the flow of ink from the nozzle flow channel RN to the connecting flow channel RR1 are smoother. Therefore, compared with a method where the inclined surface HD1 is not provided between the wall surface HNb and the wall surface HRb1, the liquid ejector head 1 according to this embodiment can reduce the possibility of air bubbles being trapped in the connecting flow channel RR1 and the nozzle flow channel RN. Thus, compared with a method where the inclined surface HD1 is not provided between the wall surface HNb and the wall surface HRb1, the liquid ejector head 1 according to this embodiment can reduce the possibility of ejection abnormalities due to air bubbles.

[0095] Furthermore, since pressure chambers CB1 and CB2 are connected via connecting channel RR1, nozzle channel RN, and connecting channel RR2 in the liquid ejector head 1 according to this embodiment, ink flow can occur between pressure chambers CB1 and CB2. Therefore, compared to a configuration where pressure chambers CB1 and CB2 are not connected, the liquid ejector head 1 according to this embodiment can reduce the possibility of air bubbles remaining in the nozzle channel RN, etc. Thus, compared to a configuration where pressure chambers CB1 and CB2 are not connected, the liquid ejector head 1 according to this embodiment can reduce the possibility of ejection abnormalities due to air bubbles.

[0096] In addition, in this embodiment, pressure chamber CB1 is an example of a "first pressure chamber", pressure chamber CB2 is an example of a "second pressure chamber", connecting channel RR1 is an example of a "first connecting channel", connecting channel RR2 is an example of a "second connecting channel", wall surface HNa is an example of a "first wall surface", wall surface HNb is an example of a "second wall surface", wall surface HRa1 is an example of a "third wall surface", wall surface HRb1 is an example of a "fourth wall surface", inclined surface HD1 is an example of a "fifth wall surface", ink is an example of a "liquid", +X direction is an example of a "first direction", -Z direction is an example of a "second direction", and W1 direction is an example of a "third direction".

[0097] Furthermore, the liquid ejector head 1 according to this embodiment is characterized by comprising: a pressure chamber CB2 extending in the -X direction and applying pressure to the ink; a pressure chamber CB1 extending in the -X direction and applying pressure to the ink; a nozzle flow channel RN extending in the -X direction and communicating with a nozzle N for ejecting ink; a connecting flow channel RR2 extending in the -Z direction and communicating between the pressure chamber CB2 and the nozzle flow channel RN; and a connecting flow channel RR1 extending in the -Z direction and communicating between the pressure chamber CB1 and the nozzle flow channel RN, wherein the wall surface of the nozzle flow channel RN includes a wall surface HNa and a wall surface HNa. HNb, the wall surface HNa extends in the -X direction and is provided with a nozzle N, the wall surface HNb extends in the -X direction and is located on the opposite side of the wall surface HNa, the wall surface of the connecting channel RR2 includes wall surface HRa2 and wall surface HRb2, the wall surface HRa2 extends in the -Z direction and is farthest from the nozzle N in the -X direction, the wall surface HRb2 extends in the -Z direction and is located on the opposite side of the wall surface HRa2, an inclined surface HD2 is provided between the wall surface HNb and the wall surface HRb2, the inclined surface HD2 extends in the W2 direction between the -X direction and the -Z direction.

[0098] Therefore, compared to a method where the inclined surface HD2 is not provided between the wall surface HNb and the wall surface HRb2, the liquid nozzle 1 according to this embodiment can reduce the possibility of air bubbles being trapped in the connecting flow channel RR2 and the nozzle flow channel RN. Thus, compared to a method where the inclined surface HD2 is not provided between the wall surface HNb and the wall surface HRb2, the liquid nozzle 1 according to this embodiment can reduce the possibility of ejection abnormalities due to air bubbles.

[0099] Furthermore, compared to the configuration where the liquid nozzle 1 of this embodiment is not connected to pressure chambers CB1 and CB2, the possibility of air bubbles remaining in the nozzle flow channel RN, etc., can be reduced. Therefore, compared to the configuration where the liquid nozzle 1 of this embodiment is not connected to pressure chambers CB1 and CB2, the possibility of ejection abnormalities due to air bubbles can be reduced.

[0100] In particular, pressure chamber CB2 is located downstream of nozzle N in the ink flow within circulation channel RJ. Air bubbles introduced from nozzle N flow with the ink flow to some extent, and therefore tend to move further downstream of nozzle N than upstream of it. That is, air bubbles are more likely to remain on the -X side of wall HNb and wall HRb2 than on the +X side of wall HNb and wall HRb1. Here, if piezoelectric element PZ2 is not provided downstream of nozzle N, the ejection abnormality caused by air bubbles remaining downstream of nozzle N is not significant. However, as in this embodiment, when piezoelectric element PZ2 is provided downstream of nozzle N, since air bubbles are more likely to remain downstream of nozzle N within circulation channel RJ, significant ejection abnormalities may occur in the ink ejection driven by piezoelectric element PZ2. In contrast, according to this embodiment, since the inclined surface HD2 is provided on the downstream side compared to the nozzle N, even when the piezoelectric element PZ2 is provided on the downstream side compared to the nozzle N, the occurrence of ejection abnormalities can be suppressed.

[0101] In addition, in this embodiment, pressure chamber CB2 is another example of a "first pressure chamber", pressure chamber CB1 is another example of a "second pressure chamber", connecting channel RR2 is another example of a "first connecting channel", connecting channel RR1 is another example of a "second connecting channel", wall surface HRa2 is another example of a "third wall", wall surface HRb2 is another example of a "fourth wall", inclined surface HD2 is another example of a "fifth wall", -X direction is another example of a "first direction", and W2 direction is another example of a "third direction".

[0102] Furthermore, the liquid ejector head 1 according to this embodiment is characterized in that the angle θ11 formed by the normal direction of the wall surface HNb and the normal direction of the inclined surface HD1 is greater than 20 degrees and less than 80 degrees.

[0103] Therefore, in the liquid nozzle 1 according to this embodiment, compared with a method in which no inclined surface HD1 is provided between the wall surface HNb and the wall surface HRb1 and the angle between the normal direction of the wall surface HNb and the normal direction of the wall surface HRb1 is, for example, 90 degrees, the possibility of air bubbles being trapped in the connecting flow channel RR1 and the nozzle flow channel RN can be reduced. Thus, the liquid nozzle 1 according to this embodiment, compared with a method in which no inclined surface HD1 is provided between the wall surface HNb and the wall surface HRb1, can reduce the possibility of ejection abnormalities due to air bubbles.

[0104] Furthermore, the liquid ejector head 1 according to this embodiment is characterized in that the angle θ12 formed by the normal direction of the wall surface HRb1 and the normal direction of the inclined surface HD1 is greater than 10 degrees and less than 70 degrees.

[0105] Therefore, according to this embodiment, compared to a configuration where no inclined surface HD1 is provided between wall surface HNb and wall surface HRb1, and the angle between the normal direction of wall surface HNb and the normal direction of wall surface HRb1 is, for example, 90 degrees, the possibility of air bubbles remaining in the connecting flow channel RR1 and the nozzle flow channel RN can be reduced. Thus, the liquid ejector head 1 according to this embodiment can suppress the possibility of ejection abnormalities due to air bubbles compared to a configuration where no inclined surface HD1 is provided between wall surface HNb and wall surface HRb1.

[0106] Furthermore, the liquid ejector head 1 according to this embodiment is characterized in that the wall surface HNa is connected to the wall surface HRa1.

[0107] Therefore, according to this embodiment, the liquid ejector head 1 can be manufactured more easily than by providing other structural elements between the wall surface HNa and the wall surface HRa1.

[0108] Furthermore, the liquid ejector head 1 according to this embodiment is characterized in that the wall of the pressure chamber CB1 includes a wall surface HC1 extending in the +X direction, and the wall surface HRa1 is connected to the wall surface HC1.

[0109] Therefore, according to this embodiment, the liquid ejector head 1 can be manufactured more easily than by providing other structural elements between the wall surface HRa1 and the wall surface HC1.

[0110] In addition, in this embodiment, wall HC1 is an example of a "sixth wall".

[0111] Furthermore, the liquid nozzle 1 according to this embodiment is characterized in that the wall of the connecting channel RR2 includes a wall HRa2 and a wall HRb2, the wall HRa2 extends in the -Z direction and is furthest from the nozzle N in the +X direction, the wall HRb2 extends in the -Z direction and is located on the side opposite to the wall HRa2, and an inclined surface HD2 is provided between the wall HNb and the wall HRb2, the inclined surface HD2 extending in the W2 direction between the -X direction and the -Z direction.

[0112] Therefore, according to this embodiment, compared to a method in which the inclined surface HD2 is not provided between the wall surface HNb and the wall surface HRb2, the possibility of air bubbles being trapped in the connecting flow channel RR2 and the nozzle flow channel RN can be reduced. Thus, the liquid ejector head 1 according to this embodiment can reduce the possibility of ejection abnormalities due to air bubbles compared to a method in which the inclined surface HD2 is not provided between the wall surface HNb and the wall surface HRb2.

[0113] In addition, in this embodiment, wall surface HRa2 is an example of a "seventh wall surface", wall surface HRb2 is an example of an "eighth wall surface", inclined surface HD2 is an example of a "ninth wall surface", and direction W2 is an example of a "fourth direction".

[0114] Furthermore, the liquid ejector head 1 according to this embodiment is characterized in that the angle θ12 formed by the W1 direction and the -Z direction and the angle θ22 formed by the W2 direction and the -Z direction are approximately the same.

[0115] Therefore, according to this embodiment, the flow path shape of the ink from pressure chamber CB1 through connecting flow path RR1 and nozzle flow path RN to nozzle N can be made substantially the same as the flow path shape of the ink from pressure chamber CB2 through connecting flow path RR2 and nozzle flow path RN to nozzle N. Thus, according to this embodiment, for example, compared to methods where angles θ12 and θ22 are different, the control for ejecting ink filled in pressure chamber CB1 from nozzle N and the control for ejecting ink filled in pressure chamber CB2 from nozzle N can be simplified.

[0116] Furthermore, the liquid ejector head 1 according to this embodiment is characterized by comprising: a supply channel RA1, which is connected to a pressure chamber CB1 and supplies ink to the pressure chamber CB1; and a discharge channel RA2, which is connected to a pressure chamber CB2 and discharges ink from the pressure chamber CB2.

[0117] Therefore, according to this embodiment, ink flow can be generated between pressure chamber CB1 and pressure chamber CB2. Thus, compared to a method where no ink flow is generated between pressure chamber CB1 and pressure chamber CB2, the liquid ejector head 1 according to this embodiment can reduce the possibility of air bubbles remaining in the nozzle flow channel RN, etc. Consequently, compared to a method where no ink flow is generated between pressure chamber CB1 and pressure chamber CB2, the liquid ejector head 1 according to this embodiment can reduce the possibility of ejection abnormalities due to air bubbles.

[0118] Furthermore, the liquid ejector head 1 according to this embodiment is characterized by comprising: a pressure chamber substrate 3, which is provided with pressure chamber CB1 and pressure chamber CB2; a connecting plate 2, which is provided with nozzle flow channel RN, connecting flow channel RR1 and connecting flow channel RR2; and a nozzle substrate 60, which is provided with nozzle N.

[0119] Therefore, according to this embodiment, pressure chamber CB1, pressure chamber CB2, nozzle flow channel RN, connecting flow channel RR1, connecting flow channel RR2, and nozzle N can be manufactured using semiconductor manufacturing technology. Therefore, according to this embodiment, pressure chamber CB1, pressure chamber CB2, nozzle flow channel RN, connecting flow channel RR1, connecting flow channel RR2, and nozzle N can be miniaturized and made more dense.

[0120] Furthermore, the liquid ejector head 1 according to this embodiment is characterized in that the nozzle N is connected to the nozzle flow channel RN at approximately the center of the nozzle flow channel RN.

[0121] Therefore, according to this embodiment, the flow path shape of the ink from pressure chamber CB1 via connecting flow path RR1 and nozzle flow path RN to nozzle N can be made substantially the same as the flow path shape of the ink from pressure chamber CB2 via connecting flow path RR2 and nozzle flow path RN to nozzle N. Thus, according to this embodiment, for example, compared to a method where nozzle N is connected to nozzle flow path RN at a position different from the center of nozzle flow path RN, the control for ejecting ink filled in pressure chamber CB1 from nozzle N and the control for ejecting ink filled in pressure chamber CB2 from nozzle N can be simplified.

[0122] Furthermore, the liquid ejector head 1 according to this embodiment is characterized by comprising: a piezoelectric element PZ1, which applies pressure to the ink in the pressure chamber CB1 according to the supply of a drive signal Com1; and a piezoelectric element PZ2, which applies pressure to the ink in the pressure chamber CB2 according to the supply of a drive signal Com2.

[0123] Therefore, according to this embodiment, compared with a piezoelectric element PZq that only applies pressure to the ink in one pressure chamber CBq, the amount of ink ejected from the nozzle N can be increased.

[0124] In addition, in this embodiment, piezoelectric element PZ1 is an example of a "first element", piezoelectric element PZ2 is an example of a "second element", drive signal Com1 is an example of a "first drive signal", and drive signal Com2 is an example of a "second drive signal".

[0125] Furthermore, the liquid ejector head 1 according to this embodiment is characterized in that the waveforms of the drive signal Com1 and the drive signal Com2 are approximately the same.

[0126] Therefore, according to this embodiment, compared with the different waveforms of drive signal Com1 and drive signal Com2, the control for ejecting ink filled in pressure chamber CB1 from nozzle N and the control for ejecting ink filled in pressure chamber CB2 from nozzle N can be simplified.

[0127] B. Variations

[0128] The methods illustrated above can be modified in a variety of ways. Specific modifications are illustrated below. Two or more methods selected from the following examples can be appropriately combined without contradiction.

[0129] Variation Example 1

[0130] Although the above embodiments illustrate a connection between wall surface HNa and wall surface HRa1 and between wall surface HNa and wall surface HRa2, the present invention is not limited to this configuration. For example, other walls may be provided between wall surface HNa and wall surface HRa1, or between wall surface HNa and wall surface HRa2.

[0131] Figure 9 This is a cross-sectional view of the liquid nozzle 1A involved in this modification. Except for the fact that a connecting plate 2A is provided instead of a connecting plate 2, the liquid nozzle 1A involved in this modification is constructed in the same manner as the liquid nozzle 1.

[0132] like Figure 9 As shown, the connecting plate 2A differs from the connecting plate 2 in the embodiment in that it has hollow portions RX1 and RX2. Here, the hollow portion RX1 communicates with the nozzle flow channel RN and is provided on the +X side of the nozzle flow channel RN. Furthermore, the hollow portion RX2 communicates with the nozzle flow channel RN and is provided on the -X side of the nozzle flow channel RN. Additionally, an inclined surface HX1 may be provided between the wall surface of the hollow portion RX1 and the wall surface HRa1, and the inclined surface HX1 extends along the W2 direction when viewed from the Y-axis direction. Similarly, an inclined surface HX2 may be provided between the wall surface of the hollow portion RX2 and the wall surface HRa2, and the inclined surface HX2 extends along the W1 direction when viewed from the Y-axis direction.

[0133] In this modified example, since an inclined surface HD1 is provided between wall surface HNb and wall surface HRb1, the possibility of bubbles being trapped in the connecting channel RR1 and the nozzle channel RN is reduced compared to the method where no inclined surface HD1 is provided between wall surface HNb and wall surface HRb1. Furthermore, in this modified example, since an inclined surface HD2 is provided between wall surface HNb and wall surface HRb2, the possibility of bubbles being trapped in the connecting channel RR2 and the nozzle channel RN is also reduced compared to the method where no inclined surface HD2 is provided between wall surface HNb and wall surface HRb2.

[0134] Variation Example 2

[0135] Although the above embodiments and variation 1 illustrate a configuration where two piezoelectric elements PZq, PZ1 and PZ2, are provided for each nozzle N, the present invention is not limited to this configuration. For example, one piezoelectric element PZ may be provided for each nozzle N.

[0136] Figure 10 This is an exploded perspective view of the liquid ejector head 1B involved in this modified example.

[0137] like Figure 10 As shown, the liquid nozzle 1B involved in this modified example differs from the liquid nozzle 1 involved in the embodiment in the following aspects: a nozzle substrate 60B is provided instead of a nozzle substrate 60, a connecting plate 2B is provided instead of a connecting plate 2, a pressure chamber substrate 3B is provided instead of a pressure chamber substrate 3, and a vibrating plate 4B is provided instead of a vibrating plate 4.

[0138] The nozzle substrate 60B differs from the nozzle substrate 60 of the embodiment in that it provides nozzle rows Ln1 and Ln2 instead of nozzle rows Ln. Here, nozzle row Ln1 is a set of M1 nozzles N arranged extending in the Y-axis direction. Furthermore, nozzle row Ln2 is a set of M2 nozzles N arranged extending along the Y-axis direction at a position closer to the -X side than nozzle row Ln1. Here, the values ​​M1 and M2 are natural numbers greater than or equal to 1 that satisfy "M1 + M2 = M". In this modified example, a case where the value M is a natural number greater than or equal to 2 is envisioned. Furthermore, in the following text, the nozzles N constituting nozzle row Ln1 are sometimes referred to as nozzle N1, and the nozzles N constituting nozzle row Ln2 are sometimes referred to as nozzle N2.

[0139] Furthermore, the connecting plate 2B differs from the connecting plate 2 in the following aspects: instead of M connecting channels RK1, M connecting channels RK2, M connecting channels RR1, and M connecting channels RR2, it is provided with M1 connecting channels RK1 corresponding to M1 nozzles N1, M2 connecting channels RK2 corresponding to M2 nozzles N2, M1 connecting channels RR1 corresponding to M1 nozzles N1, and M2 connecting channels RR2 corresponding to M2 nozzles N2. In addition, the connecting plate 2B, like the connecting plate 2, has a supply channel RA1 extending in the Y-axis direction and a discharge channel RA2 extending along the Y-axis direction in the -X direction when viewed from the supply channel RA1.

[0140] Furthermore, the pressure chamber substrate 3B differs from the pressure chamber substrate 3 in the embodiment in that, instead of M pressure chambers CB1 and M pressure chambers CB2, it is formed with M1 pressure chambers CB1 corresponding to M1 nozzles N1 and M2 pressure chambers CB2 corresponding to M2 nozzles N2.

[0141] Furthermore, the vibrating plate 4B differs from the vibrating plate 4 in the following aspects: instead of M piezoelectric elements PZ1 and M piezoelectric elements PZ2, it is formed with M1 piezoelectric elements PZ1 corresponding to M1 nozzles N1 and M2 piezoelectric elements PZ2 corresponding to M2 nozzles N2.

[0142] Figure 11 This is a plan view of the liquid ejector head 1B when viewed from the Z-axis direction.

[0143] In this modified example, the liquid nozzle 1B has M circulation channels RJ corresponding to M nozzles N, which are disposed on the nozzle substrate 60B. In the following text, the circulation channel RJ corresponding to nozzle N1 is sometimes referred to as circulation channel RJ1, and the circulation channel RJ corresponding to nozzle N2 is sometimes referred to as circulation channel RJ2. That is, in this modified example, the supply channel RA1 and the discharge channel RA2 are connected through M1 circulation channels RJ1 and M2 circulation channels RJ2.

[0144] Furthermore, in this modified example, circulation channels RJ1 and RJ2 are alternately arranged in the Y-axis direction. Also, in this modified example, M1 circulation channels RJ1 and M2 circulation channels RJ2 are arranged such that the distance between adjacent circulation channels RJ1 and RJ2 in the Y-axis direction is a distance dY.

[0145] As described above, the circulating flow channel RJ1 has a pressure chamber CB1, and the circulating flow channel RJ2 has a pressure chamber CB2. In this modified example, as... Figure 11As shown, pressure chamber CB1 is located on the +X side compared to nozzle N1, and pressure chamber CB2 is located on the -X side compared to nozzle N2. Furthermore, as described above, the nozzle row Ln1 to which nozzle N1 belongs is located on the +X side compared to the nozzle row Ln2 to which nozzle N2 belongs. Therefore, in this modified example, pressure chamber CB1 is located on the +X side compared to pressure chamber CB2.

[0146] Furthermore, in this modified example, the circulating flow channel RJ is configured such that the width of the pressure chamber CBq in the Y-axis direction is width dCY, and the width of the portion outside the pressure chamber CBq is width dRY or less. Moreover, in this modified example, the case where width dRY and width dCY satisfy "dRY < dCY" is envisioned. Furthermore, in this modified example, as an example, the case where M1 circulating flow channels RJ1 and M2 circulating flow channels RJ2 are configured such that the interval dY and width dCY satisfy "dCY > dY" is envisioned.

[0147] Thus, in this modified example, since the positions of pressure chamber CB1 and pressure chamber CB2 in the X-axis direction are different, the spacing of the circulation channel RJ can be reduced compared to the method in which pressure chambers CB1 and CB2 are set in the same position in the X-axis direction.

[0148] Figure 12 This is a cross-sectional view of the liquid ejector head 1B, cut parallel to the XZ plane, passing through the circulation channel RJ1. Furthermore, Figure 13 This is a cross-sectional view of the liquid ejector head 1B cut parallel to the XZ plane, passing through the circulation channel RJ2.

[0149] like Figure 12 as well as Figure 13 As shown, in this modified example, the connecting plate 2B includes a substrate 21 and a substrate 22. Here, substrate 21 and substrate 22 are manufactured, for example, by processing a single-crystal silicon substrate using semiconductor manufacturing techniques such as etching. However, known materials and manufacturing methods can be used arbitrarily in the manufacture of substrate 21 and substrate 22.

[0150] like Figure 12As shown, in this modified example, the circulating flow channel RJ1 includes: a connecting flow channel RK1, which communicates with the supply flow channel RA1 and is formed on substrate 21 and substrate 22; a pressure chamber CB1, which communicates with the connecting flow channel RK1 and is formed on the pressure chamber substrate 3B; a connecting flow channel RR1, which communicates with the pressure chamber CB1 and is formed on substrate 21 and substrate 22; and a nozzle flow channel RN1, which communicates with the connecting flow channel RR1 and the nozzle N1 and is formed on the substrate 21. On substrate 21: flow channel R11, which communicates with nozzle flow channel RN1, is formed on substrate 22; flow channel R12, which communicates with flow channel R11, is formed on substrate 21; flow channel R13, which communicates with flow channel R12, is formed on nozzle substrate 60B; flow channel R14, which communicates with flow channel R13, is formed on substrate 21; flow channel R15, which communicates with flow channel R14 and discharge flow channel RA2, is formed on substrate 22.

[0151] In addition, such as Figure 13 As shown, in this modified example, the circulating flow channel RJ2 includes: a connecting flow channel RK2, which communicates with the discharge flow channel RA2 and is formed on substrate 21 and substrate 22; a pressure chamber CB2, which communicates with the connecting flow channel RK2 and is formed on pressure chamber substrate 3B; a connecting flow channel RR2, which communicates with the pressure chamber CB2 and is formed on substrate 21 and substrate 22; and a nozzle flow channel RN2, which communicates with the connecting flow channel RR2 and nozzle N2 and is formed on substrate 21 and substrate 22. On substrate 21: flow channel R21, which communicates with nozzle flow channel RN2, is formed on substrate 22; flow channel R22, which communicates with flow channel R21, is formed on substrate 21; flow channel R23, which communicates with flow channel R22, is formed on nozzle substrate 60B; flow channel R24, which communicates with flow channel R23, is formed on substrate 21; flow channel R25, which communicates with flow channel R24 and supply flow channel RA1, is formed on substrate 22.

[0152] Figure 14 This is a cross-sectional view of the pressure chamber CB1, connecting channel RR1, nozzle channel RN1, and channel R11 in the circulating channel RJ1.

[0153] like Figure 14As illustrated, the nozzle flow channel RN1, when viewed from the Y-axis direction, has wall surfaces HNa1, HNb1, and HNc1. Here, wall surface HNa1 is the wall surface of the nozzle flow channel RN1 on which the nozzle N1 is formed, and it extends along the X-axis direction when viewed from the Y-axis direction. Furthermore, wall surface HNb1 is the wall surface on the opposite side of wall surface HNa1 when viewed from the Y-axis direction, and it extends along the X-axis direction. Furthermore, wall surface HNc1 is the end of the nozzle flow channel RN1 on the -X side, and it extends along the Z-axis direction when viewed from the Y-axis direction.

[0154] Furthermore, the flow channel R11, when viewed from the Y-axis direction, has a wall surface H11a, a wall surface H11b, and an inclined surface H11. Here, wall surface H11a is a wall surface connected to wall surface HNc1 and extending along the X-axis direction when viewed from the Y-axis direction. Furthermore, wall surface H11b is a wall surface on the opposite side of wall surface H11a when viewed from the Y-axis direction, and also extends along the X-axis direction. Furthermore, the inclined surface H11 is a wall surface disposed between wall surface HNb1 and wall surface H11b, and extending along the W2 direction when viewed from the Y-axis direction.

[0155] Furthermore, in this modified example, the inclined surface HD1 is disposed between the wall surface HNb1 and the wall surface HRb1. Additionally, in this modified example, the wall surface HRa1 is connected to the wall surface HNa1.

[0156] Figure 15 This is a cross-sectional view of the pressure chamber CB2, connecting channel RR2, nozzle channel RN2, and channel R21 in the circulating channel RJ2.

[0157] like Figure 15 As illustrated, the nozzle flow channel RN2, when viewed from the Y-axis direction, has wall surfaces HNa2, HNb2, and HNc2. Here, wall surface HNa2 is the wall surface of the nozzle flow channel RN2 on which the nozzle N2 is formed, and it extends along the X-axis direction when viewed from the Y-axis direction. Furthermore, wall surface HNb2 is the wall surface on the opposite side of wall surface HNa2 when viewed from the Y-axis direction, and it extends along the X-axis direction. Furthermore, wall surface HNc2 is the end of the nozzle flow channel RN2 on the +X side, and it extends along the Z-axis direction when viewed from the Y-axis direction.

[0158] Furthermore, the flow channel R21, when viewed from the Y-axis direction, has a wall surface H21a, a wall surface H21b, and an inclined surface H21. Here, wall surface H21a is a wall surface connected to wall surface HNc2 and extending along the X-axis direction when viewed from the Y-axis direction. Wall surface H21b is a wall surface on the opposite side of wall surface H21a when viewed from the Y-axis direction, and also extends along the X-axis direction. Inclined surface H21 is a wall surface disposed between wall surface HNb2 and wall surface H21b, and extends along the W1 direction when viewed from the Y-axis direction.

[0159] Furthermore, in this modified example, the inclined surface HD2 is disposed between the wall surface HNb2 and the wall surface HRb2. Additionally, in this modified example, the wall surface HRa2 is connected to the wall surface HNa2.

[0160] In this modified example, since an inclined surface HD1 is provided between wall surface HNb1 and wall surface HRb1, the possibility of bubbles being trapped in the connecting flow channel RR1 and the nozzle flow channel RN1 is reduced compared to the method where no inclined surface HD1 is provided between wall surface HNb1 and wall surface HRb1. Furthermore, in this modified example, since an inclined surface HD2 is provided between wall surface HNb2 and wall surface HRb2, the possibility of bubbles being trapped in the connecting flow channel RR2 and the nozzle flow channel RN2 is reduced compared to the method where no inclined surface HD2 is provided between wall surface HNb2 and wall surface HRb2.

[0161] Variation Example 3

[0162] Although the embodiments, variations 1 and 2 described above illustrate a serial liquid ejection device 100 in which a seamless band 922, equipped with liquid ejection head 1, liquid ejection head 1A, or liquid ejection head 1B, reciprocates in the Y-axis direction, the present invention is not limited to this manner. The liquid ejection device may also be a row-type liquid ejection device in which multiple nozzles N are distributed across the entire width of the medium PP.

[0163] Figure 16This figure illustrates an example of the structure of the liquid ejection device 100C according to this modification. The liquid ejection device 100C differs from the liquid ejection device 100 according to the embodiment in that it has a control device 90C instead of a control device 90, a housing 921C instead of a housing 921, and lacks a connectorless tape 922. The control device 90C differs from the control device 90 in that it does not output a signal to control the connectorless tape 922. The housing 921C is configured such that a plurality of liquid ejection heads 1, with the Y-axis direction as the long side direction, are distributed across the entire width of the medium PP. Furthermore, the housing 921C may also mount a liquid ejection head 1A or a liquid ejection head 1B instead of a liquid ejection head 1.

[0164] Variation Example 4

[0165] Although the above-described embodiments and variations 1 to 3 illustrate a piezoelectric element PZ that converts electrical energy into kinetic energy as an energy conversion element for applying pressure to the interior of the pressure chamber CB, the present invention is not limited to this approach. As an energy conversion element for applying pressure to the interior of the pressure chamber CB, a heating element may also be used, which converts electrical energy into heat energy and generates bubbles inside the pressure chamber CB by heating, thereby causing pressure changes inside the pressure chamber CB. The heating element may, for example, be an element that heats up by supplying a drive signal Com.

[0166] Variation Example 5

[0167] The liquid ejection apparatus illustrated in the above embodiments and variations 1 to 4 can be used not only in printing equipment but also in various other devices such as fax machines and copiers. Originally, the application of the liquid ejection apparatus of the present invention was not limited to printing. For example, a liquid ejection apparatus that ejects a solution of color material can be used as an apparatus for manufacturing color filters for forming liquid crystal display devices. Furthermore, a liquid ejection apparatus that ejects a solution of conductive material can be used as an apparatus for manufacturing wiring and electrodes for forming wiring boards.

[0168] Symbol Explanation

[0169] 1…Liquid ejector head; 2…Connecting plate; 3…Pressure chamber substrate; 4…Vibrating plate; 5…Retention chamber forming substrate; 8…Wiring substrate; 60…Nozzle substrate; 100…Liquid ejection device; CB1…Pressure chamber; CB2…Pressure chamber; HC1…Wall; HC2…Wall; HD1…Inclined surface; HD2…Inclined surface; HNa…Wall; HNb…Wall; HRa1…Wall; HRa2…Wall; HRb1…Wall; HRb2…Wall; N…Nozzle; PZ1…Piezoelectric element; PZ2…Piezoelectric element; RA1…Supply channel; RA2…Discharge channel.

Claims

1. A liquid ejector head, characterized in that, have: Pressure chamber substrate; A nozzle substrate having a nozzle for ejecting liquid; A connecting plate is disposed between the pressure chamber substrate and the nozzle substrate. The pressure chamber substrate includes: A first pressure chamber extends in a first direction and applies pressure to the liquid; A second pressure chamber extends in the first direction and applies pressure to the liquid. The connecting plate has: A nozzle flow channel that extends in the first direction and communicates with the nozzle; A first connecting channel extends in a second direction intersecting the first direction and connects the first pressure chamber with the nozzle channel; A second connecting channel extends in the second direction and connects the second pressure chamber with the nozzle channel. The nozzle flow channel has a first wall and a second wall. The first wall extends in the first direction and is provided with the nozzle. The second wall extends in the first direction and is located on the side opposite to the first wall. The walls of the first communicating channel include a third wall and a fourth wall. The third wall extends in the second direction, and the fourth wall extends in the second direction and is located on the side opposite to the third wall. A fifth wall is provided between the second wall and the fourth wall. The fifth wall extends upward in a third direction between the first direction and the second direction, and is a straight inclined surface connecting the second wall and the fourth wall. In the first direction, the distance from the third wall to the nozzle is longer than the distance from the other walls of the first communicating channel to the nozzle.

2. The liquid ejector head as described in claim 1, characterized in that, The angle between the normal direction of the second wall and the normal direction of the fifth wall is greater than 20 degrees and less than 80 degrees.

3. The liquid ejector head as described in claim 1 or 2, characterized in that, The angle between the normal direction of the fourth wall and the normal direction of the fifth wall is greater than 10 degrees and less than 70 degrees.

4. The liquid ejector head as described in claim 1, characterized in that, The first wall surface is connected to the third wall surface.

5. The liquid ejector head as described in claim 1, characterized in that, The wall of the first pressure chamber includes a sixth wall extending in the first direction. The third wall surface is connected to the sixth wall surface.

6. The liquid ejector head as described in claim 1, characterized in that, The walls of the second communicating channel include a seventh wall and an eighth wall. The seventh wall extends in the second direction and is furthest from the nozzle in the first direction. The eighth wall extends in the second direction and is located on the side opposite to the seventh wall. A ninth wall is provided between the second wall and the eighth wall, and the ninth wall extends in a fourth direction between the first direction and the second direction.

7. The liquid ejector head as described in claim 6, characterized in that, The angle between the third direction and the second direction is approximately the same as the angle between the fourth direction and the second direction.

8. The liquid ejector head as described in claim 1, characterized in that, have: A supply channel is provided, which is connected to the first pressure chamber and supplies liquid to the first pressure chamber; The discharge channel communicates with the second pressure chamber and discharges liquid from the second pressure chamber.

9. The liquid ejector head as described in claim 1, characterized in that, have: A supply channel is provided, which communicates with the second pressure chamber and supplies liquid to the second pressure chamber; The discharge channel is connected to the first pressure chamber and discharges liquid from the first pressure chamber.

10. The liquid ejector head as claimed in claim 1, characterized in that, The nozzle is in communication with the nozzle flow channel at approximately the center of the nozzle flow channel.

11. The liquid ejector head as claimed in claim 1, characterized in that, have: The first element applies pressure to the liquid in the first pressure chamber according to the supply of the first drive signal; The second element applies pressure to the liquid in the second pressure chamber according to the supply of the second drive signal.

12. The liquid ejector head as described in claim 11, characterized in that, The waveform of the first driving signal is approximately the same as the waveform of the second driving signal.

13. A liquid ejection device, characterized in that, have: Pressure chamber substrate; A nozzle substrate having a nozzle for ejecting liquid; A connecting plate is disposed between the pressure chamber substrate and the nozzle substrate. The pressure chamber substrate includes: A first pressure chamber extends in a first direction and applies pressure to the liquid; A second pressure chamber extends in the first direction and applies pressure to the liquid. The connecting plate has: A nozzle flow channel that extends in the first direction and communicates with the nozzle; A first connecting channel extends in a second direction intersecting the first direction and connects the first pressure chamber with the nozzle channel; A second connecting channel extends in the second direction and connects the second pressure chamber with the nozzle channel. The nozzle flow channel has a first wall and a second wall. The first wall extends in the first direction and is provided with the nozzle. The second wall extends in the first direction and is located on the side opposite to the first wall. The first communicating channel has a wall surface including a third wall surface and a fourth wall surface. The third wall surface extends in the second direction, and the fourth wall surface extends in the second direction and is located on the side opposite to the third wall surface. A fifth wall is provided between the second wall and the fourth wall. The fifth wall extends upward in a third direction between the first direction and the second direction, and is a straight inclined surface connecting the second wall and the fourth wall. In the first direction, the distance from the third wall to the nozzle is longer than the distance from the other walls of the first communicating channel to the nozzle.

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