Liquid discharge head and liquid discharge apparatus

Abstract

A liquid ejecting head and a liquid ejecting apparatus are provided. The liquid ejecting head includes first and second pressure chambers extending in a first direction and applying pressure to a liquid, a nozzle flow channel extending in the first direction and communicating with a nozzle that ejects the liquid, a first communication flow channel extending in a second direction intersecting the first direction and communicating the first pressure chamber with the nozzle flow channel, a second communication flow channel extending in the second direction and communicating the second pressure chamber with the nozzle flow channel, a supply flow channel that supplies the liquid to the first pressure chamber, and a discharge flow channel that discharges the liquid from the second pressure chamber. A wall surface of the second pressure chamber includes a first wall surface extending in the first direction and being farthest from the nozzle in the second direction. A wall surface of the second communication flow channel includes a second wall surface extending in the second direction and being farthest from the nozzle in the first direction, and a third wall surface opposite the second wall surface in the first direction. A first inclined portion provided between the first and third wall surfaces has a first structure surface extending in a third direction between the first and second directions.

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; a second connecting channel extending in the second direction and communicating between the second pressure chamber and the nozzle channel; a supply channel supplying liquid to the first pressure chamber; and a discharge channel. The outlet channel discharges liquid from the second pressure chamber. The wall of the second pressure chamber includes a first wall extending in the first direction and being furthest from the nozzle in the second direction. The wall of the second connecting channel includes a second wall and a third wall. The second wall extends in the second direction and is furthest from the nozzle in the first direction. The third wall is located on the side opposite to the second wall in the first direction. A first inclined portion is provided between the first wall and the third wall. The first inclined portion has a first structural surface extending 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; a second connecting channel extending in the second direction and communicating between the second pressure chamber and the nozzle channel; a supply channel supplying liquid to the first pressure chamber; and a discharge channel discharging liquid from... The second pressure chamber discharges liquid. The wall of the second pressure chamber includes a first wall extending in the first direction and being furthest from the nozzle in the second direction. The wall of the second communicating channel includes a second wall and a third wall. The second wall extends in the second direction and is furthest from the nozzle in the first direction. The third wall is located on the side opposite to the second wall in the first direction. A first inclined portion is provided between the first wall and the third wall. The first inclined portion has a first structural surface extending 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 A plan view showing an example of the structure of a liquid ejector head 1.

[0011] Figure 5 This is a cross-sectional view showing an example of the structure of a piezoelectric element PZq.

[0012] Figure 6 A cross-sectional view showing an example of the structure of a liquid ejector head 1.

[0013] Figure 7 A cross-sectional view showing an example of the structure of a liquid ejector head 1.

[0014] Figure 8 A cross-sectional view illustrating an example of the structure of the liquid ejector head 1Z involved in the reference example.

[0015] Figure 9 A plan view illustrating an example of the structure of the circulating flow channel RJA involved in Modification Example 1.

[0016] Figure 10 This is a structural diagram of an example of the liquid ejection device 100B involved in Modification Example 2. Detailed Implementation

[0017] 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.

[0018] A. Implementation Method

[0019] The following is for reference Figure 1 The liquid ejection device 100 according to this embodiment will be described.

[0020] 1. Overview of the liquid ejection device

[0021] Figure 1 This 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, for example, printing paper, any printing object such as resin film or fabric can also be used as the medium PP.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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. For example, 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 belt 922 to which the housing 921 is fixed. Alternatively, the liquid container 93 and the circulation mechanism 94 can also be stored together with the liquid nozzles 1 in the housing 921.

[0027] 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.

[0028] 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 the direction intersecting the +X and +Y directions. For example, the +Z direction is the 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 4 This will be described in the following text.

[0029] 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.

[0030] 2. Overview of the liquid nozzle

[0031] The following is for reference Figures 2 to 5 The general outline of liquid ejector head 1 will be described.

[0032] in addition, Figure 2 This is an exploded perspective view of liquid ejector head 1. Figure 3 for Figure 2 The sectional view along line III-III in the middle. Figure 4 This is a plan view of the liquid ejector head when viewed from the -Z direction.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] Furthermore, the connecting plate 2 has M nozzle channels RN, RR1, RR2, RK1, RK2, RX1, and RX2, each corresponding to one of the M nozzles N. Alternatively, a single connecting channel RX1 or RX2 shared by the M nozzles N can be provided on the connecting plate 2.

[0038] Specifically, the connecting channel RX1 is configured to communicate with the supply channel RA1 and extend along the X-axis in the -X direction when viewed from the supply channel RA1. Furthermore, the connecting channel RK1 is configured to communicate with the connecting channel RX1 and extend along the Z-axis in the -X direction when viewed from the connecting channel RX1. Additionally, the connecting channel RR1 is configured to extend along the Z-axis in the -X direction when viewed from the connecting channel RK1.

[0039] Furthermore, the connecting channel RX2 is configured to communicate with the discharge channel RA2 and extend along the X-axis in the +X direction when viewed from the discharge channel RA2. Additionally, the connecting channel RK2 is configured to communicate with the connecting channel RX2 and extend along the Z-axis in the +X direction when viewed from the connecting channel RX2. Furthermore, the connecting channel RR2 is configured to extend along the Z-axis in the +X direction when viewed from the connecting channel RK2 and in the -X direction when viewed from the connecting channel RR1.

[0040] Furthermore, 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 the nozzle channel RN.

[0041] 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.

[0042] 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.

[0043] 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. Pressure chamber CB1 is configured to connect the connecting channel RK1 and the connecting channel RR1, and when viewed from the Z-axis direction, the +X side end of the connecting channel RK1 is connected to the -X side end of the connecting channel RR1 and extends in the X-axis direction. Similarly, pressure chamber CB2 is configured to connect the connecting channel RK2 and the connecting channel RR2, and when viewed from the Z-axis direction, the -X side end of the connecting channel RK2 is connected to the +X side end of the connecting channel RR2 and extends in the X-axis direction.

[0044] 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.

[0045] In addition, although the details will be described below, the pressure chamber substrate 3 is provided with inclined portions TP1A and TP1B corresponding to the pressure chamber CB1, and inclined portions TP2A and TP2B are provided corresponding to the pressure chamber CB2.

[0046] In addition, 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.

[0047] like Figure 4 As illustrated, the supply channel RA1 and the discharge channel RA2 are connected by M circulation channels RJ corresponding one-to-one with the M nozzles N. As described above, each circulation channel RJ includes a connecting channel RX1 connected to the supply channel RA1, a connecting channel RK1 connected to the connecting channel RX1, 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, a connecting channel RK2 connected to the pressure chamber CB2, and a connecting channel RX2 connecting the connecting channel RK2 and the discharge channel RA2. Furthermore, in this embodiment, as an example, it is envisioned that each circulation channel RJ extends in the X-axis direction.

[0048] 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.

[0049] 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.

[0050] Figure 5 This is an enlarged cross-sectional view of the vicinity of the piezoelectric element PZq.

[0051] like Figure 5 As 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.

[0052] 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.

[0053] like Figure 2 as well as Figure 3As 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 5 As illustrated, the drive circuit 81 supplies a drive signal Com to the upper electrode ZUq of the piezoelectric element PZq via wiring 810.

[0054] 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.

[0055] like Figure 2 as well as Figure 3 As 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.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] 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.

[0060] 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 RX1 and 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, connecting channel RX2, discharge channel RA2, and discharge channel RB2.

[0061] 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.

[0062] like Figure 2 and 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, the connecting channel RX1, and the connecting channel RK1. The plastic sheet 61 is formed of an elastic material and absorbs pressure fluctuations of the ink within the supply channel RA1, the connecting channel RX1, 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, the connecting channel RX2, and the connecting channel RK2. The plastic sheet 62 is formed of an elastic material and absorbs pressure fluctuations of the ink within the discharge channel RA2, the connecting channel RX2, and the connecting channel RK2.

[0063] 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.

[0064] 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.

[0065] 3. Shape of the pressure chamber

[0066] The following is for reference Figure 6 and Figure 7 The shape of the pressure chamber CBq is described.

[0067] Figure 6 This is a cross-sectional view of the nozzle channel RN, connecting channel RR1, pressure chamber CB1, connecting channel RK1, and connecting channel RX1 in the circulating channel RJ.

[0068] like Figure 6 As illustrated, 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.

[0069] Furthermore, the connecting channel RK1, when viewed from the Y-axis direction, has a wall surface HKa1 on the -X side and a wall surface HKb1 on the +X side. Here, wall surface HKb1 is the wall surface that is furthest from the nozzle N in the X-axis direction among the walls constituting the connecting channel RK1, and it is a wall surface that extends along the Z-axis direction when viewed from the Y-axis direction. Wall surface HKa1, when viewed from the Y-axis direction, is the wall surface opposite to wall surface HKb1 among the two walls constituting the connecting channel RK1 that extend along the Z-axis direction.

[0070] In addition, the pressure chamber CB1 has a wall HC1 when viewed from the Y-axis direction. Here, the wall HC1 is the wall that is furthest from the nozzle N in the Z-axis direction among the walls constituting the pressure chamber CB1, and it is a wall that extends along the X-axis direction when viewed from the Y-axis direction.

[0071] like Figure 6 As illustrated, an inclined portion TP1A is provided on the pressure chamber base plate 3 between the wall surface HRb1 and the wall surface HC1. Here, the inclined portion TP1A has a wall surface HP11, a wall surface HP12 and a wall surface HP13.

[0072] The wall HP11 extends along the W11 direction when viewed from the Y-axis and connects to the wall HC1. Here, the W11 direction refers to the direction between the +X and -Z directions. Specifically, the W11 direction is the direction after rotating the +X direction counterclockwise by an angle θ11 when viewed from the +Y direction. Here, the angle θ11 is an angle greater than 0 degrees and less than 90 degrees, preferably greater than 30 degrees and less than 60 degrees.

[0073] Furthermore, wall HP13 extends along the W11 direction when viewed from the Y-axis and connects to wall HRb1. Additionally, wall HP12 extends along the W12 direction when viewed from the Y-axis and connects to wall HP11 and wall HP13. Here, the W12 direction refers to the direction between the +X direction and the W11 direction. Specifically, the W12 direction is the direction after rotating the +X direction counterclockwise by an angle θ12 when viewed from the +Y direction. Here, angle θ12 is an angle greater than 0 degrees and less than angle θ11. Alternatively, wall HP12 can also extend along the +X direction when viewed from the Y-axis.

[0074] like Figure 6As illustrated, an inclined portion TP1B is provided on the pressure chamber base plate 3 between wall surface HKb1 and wall surface HC1. Here, the inclined portion TP1B has a wall surface HP14. Wall surface HP14 extends along the W13 direction when viewed from the Y-axis direction and connects wall surface HKb1 and wall surface HC1. Here, the W13 direction is the direction between the -X direction and the -Z direction. Specifically, the W13 direction is the direction after rotating the -X direction clockwise by an angle θ13 when viewed from the +Y direction. Here, the angle θ13 is an angle greater than 0 degrees and less than 90 degrees, preferably greater than 30 degrees and less than 60 degrees. For example, the angle θ13 can also be approximately the same as the angle θ11.

[0075] Figure 7 This is a cross-sectional view of the nozzle channel RN, connecting channel RR2, pressure chamber CB2, connecting channel RK2, and connecting channel RX2 in the circulating channel RJ.

[0076] like Figure 7 As illustrated, 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. Additionally, 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.

[0077] Furthermore, the connecting channel RK2, when viewed from the Y-axis direction, has a wall surface HKa2 on the +X side and a wall surface HKb2 on the -X side. Here, wall surface HKb2 is the wall surface that is furthest from the nozzle N in the X-axis direction among the walls constituting the connecting channel RK2, and it is a wall surface that extends along the Z-axis direction when viewed from the Y-axis direction. Wall surface HKa2, when viewed from the Y-axis direction, is the wall surface opposite to wall surface HKb2 among the two walls constituting the connecting channel RK2 that extend along the Z-axis direction.

[0078] In addition, the pressure chamber CB2 has a wall HC2 when viewed from the Y-axis direction. Here, the wall HC2 is the wall that is furthest from the nozzle N in the Z-axis direction among the walls constituting the pressure chamber CB2, and is a wall that extends along the X-axis direction when viewed from the Y-axis direction.

[0079] like Figure 7As illustrated, an inclined portion TP2A is provided on the pressure chamber substrate 3 between the wall surface HRb2 and the wall surface HC2. Here, the inclined portion TP2A has a wall surface HP21, a wall surface HP22 and a wall surface HP23.

[0080] The wall HP21 extends along the W21 direction when viewed from the Y-axis and connects to the wall HC2. Here, the W21 direction is the direction between the -X and -Z directions. Specifically, the W21 direction is the direction after rotating the -X direction clockwise by an angle θ21 when viewed from the +Y direction. Here, the angle θ21 is an angle greater than 0 degrees and less than 90 degrees, preferably greater than 30 degrees and less than 60 degrees. For example, the angle θ21 can also be approximately the same as the angle θ11.

[0081] Furthermore, wall HP23 extends along the W21 direction when viewed from the Y-axis and connects to wall HRb2. Additionally, wall HP22 extends along the W22 direction when viewed from the Y-axis and connects to wall HP21 and wall HP23. Here, the W22 direction is the direction between the -X direction and the W21 direction. Specifically, the W22 direction is the direction after rotating the -X direction clockwise by an angle θ22 when viewed from the +Y direction. Here, angle θ22 is an angle greater than 0 degrees and less than angle θ21. For example, angle θ22 can also be approximately the same as angle θ12.

[0082] Furthermore, the wall surface HP22 can also extend along the -X direction when viewed from the Y-axis direction. Additionally, the inclined portion TP2A can have approximately the same shape as the inclined portion TP1A. Specifically, the inclined portions TP1A and TP2A can, for example, be configured to be surface-symmetrical with reference to a plane passing through the nozzle N and parallel to the YZ plane.

[0083] like Figure 7 As illustrated, an inclined portion TP2B is provided on the pressure chamber base plate 3 between wall surface HKb2 and wall surface HC2. Here, the inclined portion TP2B has a wall surface HP24. Wall surface HP24 extends along the W23 direction when viewed from the Y-axis direction and connects wall surface HKb2 and wall surface HC2. Here, the W23 direction is the direction between the +X direction and the -Z direction. Specifically, the W23 direction is the direction after rotating the +X direction counterclockwise by an angle θ23 when viewed from the +Y direction. Here, the angle θ23 is an angle greater than 0 degrees and less than 90 degrees, preferably greater than 30 degrees and less than 60 degrees. For example, angle θ23 may also be approximately the same as angle θ21. Alternatively, for example, angle θ23 may also be approximately the same as angle θ13.

[0084] Alternatively, the inclined portion TP2B may have a shape substantially the same as that of the inclined portion TP1B. Specifically, the inclined portions TP1B and TP2B may, for example, be configured to be surface-symmetrical with reference to a plane passing through the nozzle N and parallel to the YZ plane.

[0085] 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.

[0086] 4. Reference Example

[0087] To clarify the effects of this embodiment, the following will refer to... Figure 8 The liquid ejector head 1Z described in the reference example will now be explained. Except for the fact that a pressure chamber substrate 3Z is provided instead of a pressure chamber substrate 3, the liquid ejector head 1Z is constructed in the same manner as the liquid ejector head 1 of the embodiment. Furthermore, except for the fact that the inclined portions TP1A, TP1B, TP2A, and TP2B are not provided, the pressure chamber substrate 3Z is constructed in the same manner as the pressure chamber substrate 3 of the embodiment. Additionally, the circulation channel RJZ of the liquid ejector head 1Z differs from the circulation channel RJ of the embodiment in that a pressure chamber CB1Z is provided instead of a pressure chamber CB1, and a pressure chamber CB2Z is ​​provided instead of a pressure chamber CB2.

[0088] Figure 8 This is a cross-sectional view of the nozzle channel RN, connecting channel RR2, pressure chamber CB2Z, connecting channel RK2, and connecting channel RX2, which are disposed in the circulation channel RJZ of the liquid nozzle 1Z involved in the reference example.

[0089] like Figure 8 As illustrated, the pressure chamber CB2Z includes two walls HC21 and HC22 that constitute the pressure chamber CB2Z and extend along the Z-axis. Here, wall HC21 is the +X side wall of the two walls constituting the pressure chamber CB2Z and extending along the Z-axis, and it connects to wall HC2 and wall HRb2. Similarly, wall HC22 is the -X side wall of the two walls constituting the pressure chamber CB2Z and extending along the Z-axis, and it connects to wall HC2 and wall HRb2.

[0090] In the liquid ejector head 1Z described in the reference example, when ink flows from the supply channel RA1 through the circulation channel RJZ to the discharge channel RA2, the ink flow rate decreases in region Ar1 (the boundary between wall HC2 and wall HC21) and region Ar2 (the boundary between wall HC2 and wall HC22), causing ink retention. Therefore, the likelihood of air bubbles generated in the circulation channel RJZ remaining in regions Ar1 and Ar2 increases. Furthermore, even when the piezoelectric element PZ2 is driven by the drive signal Com2 to eject ink from the nozzle N into the pressure chamber CB2Z, the pressure that the piezoelectric element PZ2 intends to expel is absorbed by the air bubbles remaining in regions Ar1 and Ar2 within the pressure chamber CB2Z, resulting in a so-called ejection anomaly where ink is difficult to eject from the nozzle N. Moreover, in the event of an ejection anomaly, the image quality of the image formed on the medium PP deteriorates.

[0091] Similarly, in the liquid ejector head 1Z involved in the reference example, there is also a situation where the pressure that the piezoelectric element PZ1 wants to press out the ink is absorbed by the air bubbles trapped in the pressure chamber CB1Z, making it difficult to eject the ink from the nozzle N.

[0092] In contrast, in the liquid ejector head 1 according to this embodiment, inclined portions TP2A and TP2B are provided in the pressure chamber CB2. Therefore, compared with liquid ejector head 1Z, the possibility of air bubbles remaining in the pressure chamber CB2 can be reduced in the liquid ejector head 1 according to this embodiment. Furthermore, in the liquid ejector head 1 according to this embodiment, compared with liquid ejector head 1Z, inclined portions TP1A and TP1B are provided in the pressure chamber CB1. Therefore, compared with liquid ejector head 1Z, the possibility of air bubbles remaining in the pressure chamber CB1 can be reduced in the liquid ejector head 1 according to this embodiment. Therefore, compared with liquid ejector head 1Z, the possibility of ejection abnormalities due to air bubbles can be reduced in the liquid ejector head 1 according to this embodiment. Thus, compared with liquid ejector head 1Z, the liquid ejector head 1 according to this embodiment can form images of higher quality for the medium PP.

[0093] 5. Summary of Implementation Methods

[0094] 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 ink; a pressure chamber CB2 extending in the -X direction and applying pressure to 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; a connecting flow channel RR2 extending in the -Z direction and communicating between the pressure chamber CB2 and the nozzle flow channel RN; a supply flow channel RA1 supplying ink to the pressure chamber CB1; and a discharge flow channel. The flow channel RA2 discharges ink from the pressure chamber CB2. The wall of the pressure chamber CB2 includes a wall HC2, which extends in the -X direction and is furthest from the nozzle N in the -Z direction. The wall of the flow channel RR2 includes a wall HRa2 and a wall HRb2, which extends in the -Z direction and is furthest from the nozzle N in the -X direction. The wall HRb2 is located on the opposite side of the wall HRa2 in the -X direction. An inclined portion TP2A is provided between the wall HC2 and the wall HRb2. The inclined portion TP2A has a wall HP21, which extends in the W21 direction between the -X and -Z directions.

[0095] That is, since the liquid ejector head 1 according to this embodiment has an inclined portion TP2A in the pressure chamber CB2, compared with the method where the inclined portion TP2A is not provided in the pressure chamber CB2, the flow of ink from the connecting channel RR2 toward the pressure chamber CB2 and the flow of ink from the pressure chamber CB2 toward the connecting channel RR2 can be smoother. Therefore, compared with the method where the inclined portion TP2A is not provided in the pressure chamber CB2, the liquid ejector head 1 according to this embodiment can reduce the possibility of air bubbles being trapped in the connecting channel RR2 and the pressure chamber CB2. Thus, compared with the method where the inclined portion TP2A is not provided in the pressure chamber CB2, the liquid ejector head 1 according to this embodiment can reduce the possibility of ejection abnormalities due to air bubbles.

[0096] 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.

[0097] 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 HC2 is an example of a "first wall surface", wall surface HRa2 is an example of a "second wall surface", wall surface HRb2 is an example of a "third wall surface", inclined portion TP2A is an example of a "first inclined portion", wall surface HP21 is an example of a "first structural 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 W21 direction is an example of a "third direction".

[0098] Furthermore, the liquid ejector head 1 according to this embodiment is characterized in that it has a connecting channel RK2, which extends in the -Z direction and connects the connecting channel RR2 and the discharge channel RA2. The wall of the connecting channel RK2 includes a wall HKb2, which extends in the -Z direction and is furthest from the nozzle N in the -X direction. An inclined portion TP2B is provided between the wall HKb2 and the wall HC2. The inclined portion TP2B has a wall HP24 extending in the W23 direction between the +X direction and the -Z direction.

[0099] That is, since the liquid ejector head 1 according to this embodiment has an inclined portion TP2B in the pressure chamber CB2, compared with the method where the inclined portion TP2B is not provided in the pressure chamber CB2, the flow of ink from the connecting channel RK2 toward the pressure chamber CB2 and the flow of ink from the pressure chamber CB2 toward the connecting channel RK2 can be smoother. Therefore, compared with the method where the inclined portion TP2B is not provided in the pressure chamber CB2, the liquid ejector head 1 according to this embodiment can reduce the possibility of air bubbles being trapped in the connecting channel RK2 and the pressure chamber CB2. Thus, compared with the method where the inclined portion TP2B is not provided in the pressure chamber CB2, the liquid ejector head 1 according to this embodiment can reduce the possibility of ejection abnormalities due to air bubbles.

[0100] In addition, in this embodiment, the connecting channel RK2 is an example of a "third connecting channel", the wall HKb2 is an example of a "fourth wall", the inclined part TP2B is an example of a "second inclined part", the wall HP24 is an example of a "second structural surface", the +X direction is an example of a "fourth direction", and the W23 direction is an example of a "fifth direction".

[0101] Furthermore, in the liquid ejector head 1 of this embodiment, the angle θ21 formed by the -X direction and the W21 direction can also be approximately the same as the angle θ23 formed by the +X direction and the W23 direction.

[0102] In this case, according to this embodiment, the manufacture of the liquid ejector head 1 becomes easier compared to the case where angles θ21 and θ23 are different angles.

[0103] Furthermore, the liquid ejector head 1 according to this embodiment is characterized in that the inclined portion TP2A has a wall surface HP22, which extends in the -X direction or in the W22 direction between the -X direction and the W21 direction. In this case, the wall surface HP22 may also be provided between the wall surface HP21 and the wall surface HRb2. Alternatively, in this case, a wall surface HP23 extending along the W21 direction may also be provided between the wall surface HP22 and the wall surface HRb2.

[0104] That is, since the liquid ejector head 1 according to this embodiment has a wall surface HP22 in the inclined portion TP2A, compared with the method where the wall surface HP22 is not provided in the inclined portion TP2A, the flow of ink from the connecting channel RR2 toward the pressure chamber CB2 and the flow of ink from the pressure chamber CB2 toward the connecting channel RR2 can be made smoother. Therefore, compared with the method where the wall surface HP22 is not provided in the inclined portion TP2A, the liquid ejector head 1 according to this embodiment can reduce the possibility of air bubbles being trapped in the connecting channel RR2 and the pressure chamber CB2.

[0105] In particular, the inclined section TP2A is a structural element used to switch the ink flow direction from the +X direction to the -Z direction when ink is ejected from the nozzle N, and to switch the ink flow direction from the +Z direction to the -X direction when the ink circulates in the circulation channel RJ without ink being ejected from the nozzle N. In this embodiment, by providing a wall surface HP22 extending in the W22 direction with a smaller inclination relative to the X-axis direction in the inclined section TP2A, the ink flow direction can be smoothly switched from the +X direction to the -Z direction when ink is ejected from the nozzle N. Furthermore, in this embodiment, by providing a wall surface HP23 extending in the W21 direction with a larger inclination relative to the X-axis direction in the inclined section TP2A, the ink flow direction can be smoothly switched from the +Z direction to the -X direction when the ink circulates in the circulation channel RJ without ink being ejected from the nozzle N.

[0106] In addition, in this embodiment, wall surface HP22 is an example of a "third structural surface", and direction W22 is an example of a "sixth direction".

[0107] Furthermore, the liquid ejector head 1 according to this embodiment is characterized in that the wall of the pressure chamber CB1 includes a wall HC1, which extends in the -X direction and is furthest from the nozzle N in the -Z direction; the wall of the connecting channel RR1 includes a wall HRa1 and a wall HRb1, which extends in the -Z direction and is furthest from the nozzle N in the +X direction; the wall HRb1 is located on the opposite side of the wall HRa1 in the -X direction; and an inclined portion TP1A is provided between the wall HC1 and the wall HRb1, the inclined portion TP1A having a wall HP11 extending in the W11 direction between the -Z and +X directions.

[0108] That is, since the liquid ejector head 1 according to this embodiment has an inclined portion TP1A in the pressure chamber CB1, compared with the method where the inclined portion TP1A is not provided in the pressure chamber CB1, the flow of ink from the connecting channel RR1 towards the pressure chamber CB1 and the flow of ink from the pressure chamber CB1 towards the connecting channel RR1 can be smoother. Therefore, compared with the method where the inclined portion TP1A is not provided in the pressure chamber CB1, the liquid ejector head 1 according to this embodiment can reduce the possibility of air bubbles being trapped in the connecting channel RR1 and the pressure chamber CB1. Thus, compared with the method where the inclined portion TP1A is not provided in the pressure chamber CB1, the liquid ejector head 1 according to this embodiment can reduce the possibility of ejection abnormalities due to air bubbles.

[0109] In addition, in this embodiment, wall HC1 is an example of a "fifth wall", wall HRa1 is an example of a "sixth wall", wall HRb1 is an example of a "seventh wall", inclined part TP1A is an example of a "third inclined part", wall HP11 is an example of a "fourth structural surface", and the W11 direction is another example of a "fifth direction".

[0110] In addition, in the liquid ejector head 1 of this embodiment, the inclined portion TP2A and the inclined portion TP1A may have approximately the same shape.

[0111] In this embodiment, when the inclined portions TP2A and TP1A have approximately the same shape, the manufacture of the liquid ejector head 1 becomes easier compared to the case where the inclined portions TP2A and TP1A have different shapes.

[0112] Furthermore, in this embodiment, when the inclined portions TP2A and TP1A have approximately the same shape, the flow path shape of the ink from pressure chamber CB1 through the connecting flow channel RR1 and the nozzle flow channel RN to nozzle N can be made approximately the same as the flow path shape of the ink from pressure chamber CB2 through the connecting flow channel RR2 and the nozzle flow channel RN to nozzle N. Therefore, in this embodiment, when the inclined portions TP2A and TP1A have approximately the same shape, compared to when the inclined portions TP2A and TP1A have different shapes, 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.

[0113] Furthermore, the liquid ejector head 1 according to this embodiment is characterized in that it has a connecting channel RK1, which extends in the -Z direction and connects the pressure chamber CB1 and the supply channel RA1. The wall of the connecting channel RK1 includes a wall HKb1 that extends in the -Z direction and is furthest from the nozzle N in the +X direction. An inclined portion TP1B is provided between the wall HKb1 and the wall HC1. The inclined portion TP1B has a wall HP14 that extends in the W13 direction.

[0114] That is, because the liquid ejector head 1 according to this embodiment has an inclined portion TP1B in the pressure chamber CB1, compared with the method where the inclined portion TP1B is not provided in the pressure chamber CB1, the flow of ink from the connecting channel RK1 to the pressure chamber CB1 and the flow of ink from the pressure chamber CB1 to the connecting channel RK1 can be smoother. Therefore, compared with the method where the inclined portion TP1B is not provided in the pressure chamber CB1, the liquid ejector head 1 according to this embodiment can reduce the possibility of air bubbles being trapped in the connecting channel RK1 and the pressure chamber CB1. Thus, compared with the method where the inclined portion TP1B is not provided in the pressure chamber CB1, the liquid ejector head 1 according to this embodiment can reduce the possibility of ejection abnormalities due to air bubbles.

[0115] In addition, in this embodiment, the connecting channel RK1 is an example of a "fourth connecting channel", the wall HKb1 is an example of an "eighth wall", the inclined part TP1B is an example of a "fourth inclined part", the wall HP14 is an example of a "fifth structural surface", and the W13 direction is another example of a "third direction".

[0116] 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, connecting flow channel RR2, supply flow channel RA1 and discharge flow channel RA2; and a nozzle substrate 60, which is provided with nozzle N.

[0117] Therefore, according to this embodiment, pressure chamber CB1, pressure chamber CB2, nozzle flow channel RN, connecting flow channel RR1, connecting flow channel RR2, supply flow channel RA1, discharge flow channel RA2, and nozzle N can be manufactured using semiconductor manufacturing technology. Thus, according to this embodiment, pressure chamber CB1, pressure chamber CB2, nozzle flow channel RN, connecting flow channel RR1, connecting flow channel RR2, supply flow channel RA1, discharge flow channel RA2, and nozzle N can be miniaturized and made more dense.

[0118] Furthermore, the liquid ejector head 1 according to this embodiment is characterized in that the inclined portion TP2A is provided on the pressure chamber substrate 3.

[0119] Therefore, according to this embodiment, the tilted portion TP2A can be manufactured using semiconductor manufacturing technology. Consequently, according to this embodiment, the tilted portion TP2A can be miniaturized and its density increased.

[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 in the above-described embodiments, such as Figure 4 As shown, the pressure chamber CBq is illustrated as a rectangle when viewed from the Z-axis direction, but the invention is not limited to this shape. The shape of the pressure chamber CBq when viewed from the Z-axis direction can be any shape. For example, a parallelogram or trapezoid can also be used as the shape of the pressure chamber CBq when viewed from the Z-axis direction. Furthermore, the shape of the circulation channel RJ when viewed from the Z-axis direction is not limited to... Figure 4 The shape shown. The shape of the circulation channel RJ when viewed from the Z-axis direction can also be any shape.

[0131] Figure 9 This is a plan view of the circulating flow channel RJA involved in this modified example, viewed from the Z-axis direction.

[0132] like Figure 9 As shown, in this modified example, the circulating flow channel RJA differs from the circulating flow channel RJ in the embodiment in that it has pressure chambers CB1A and CB2A instead of pressure chambers CB1 and CB2. Pressure chamber CB1A is configured such that its width dY1A in the Y-axis direction at the -Z side of the connecting flow channel RK1 is greater than its width dY1B in the Y-axis direction at the -Z side of the connecting flow channel RR1. Similarly, pressure chamber CB2A is configured such that its width dY2A in the Y-axis direction at the -Z side of the connecting flow channel RK2 is greater than its width dY2B in the Y-axis direction at the -Z side of the connecting flow channel RR2. Here, the widths dY2A and dY1A can be approximately the same, or the widths dY2B and dY1B can be approximately the same.

[0133] According to this modification, since the width dYqB of the pressure chamber CBq near the connecting channel RRq is narrower in the Y-axis direction than the width dYqA of the pressure chamber CBq near the connecting channel RKq, the ink flow velocity in the connecting channel RRq can be made greater than the ink flow velocity in the connecting channel RKq. Therefore, according to this modification, the possibility of air bubbles remaining in the path from the pressure chamber CBq through the connecting channel RRq and the nozzle channel RN to the nozzle N can be reduced. Thus, according to this modification, the possibility of ejection abnormalities due to air bubbles can be reduced.

[0134] Variation Example 2

[0135] Although the above-described embodiments and variations 1 illustrate a serial liquid ejection device 100 in which a seamless belt 922 equipped with a liquid ejection head 1 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.

[0136] Figure 10 This figure illustrates an example of the structure of the liquid ejection device 100B according to this modification. The liquid ejection device 100B differs from the liquid ejection device 100 according to the embodiment in that it has a control device 90B instead of a control device 90, a housing 921B instead of a housing 921, and lacks a connectorless tape 922. The control device 90B differs from the control device 90 in that it does not output a signal to control the connectorless tape 922. The housing 921B 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 921B may also mount either a liquid ejection head 1A or a liquid ejection head 1B instead of a liquid ejection head 1.

[0137] Variation Example 3

[0138] Although the above-described embodiments and modifications 1 and 2 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.

[0139] Variation Example 4

[0140] The liquid ejection apparatus illustrated in the above embodiments and modifications 1 to 3 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 a manufacturing apparatus for color filters in liquid crystal display devices. Furthermore, a liquid ejection apparatus that ejects a solution of conductive material can be used as a manufacturing apparatus for wiring and electrodes in wiring boards.

[0141] Symbol Explanation

[0142] 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; HKa1…Wall; HKa2…Wall; HKb1…Wall; HKb2…Wall; N…Nozzle; PZ1…Piezoelectric element; PZ2…Piezoelectric element; RA1…Supply channel; RA2…Discharge channel; RK1…Connecting channel; RK2…Connecting channel; RN…Nozzle channel; RR1…Connecting channel; RR2…Connecting channel; TP1A…Inclined section; TP1B…Inclined section; TP2A…Inclined section; TP2B…Inclined section.

Claims

1. A liquid ejector head, characterized in that, have: 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; A nozzle flow channel extends in the first direction and communicates with a nozzle that ejects liquid. 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; A supply channel that supplies liquid to the first pressure chamber; The discharge channel discharges liquid from the second pressure chamber; A third connecting channel extends in the second direction and connects the second pressure chamber with the discharge channel. The wall of the second pressure chamber includes a first wall extending in the first direction and being furthest from the nozzle in the second direction. The wall of the second communicating channel includes a second wall and a third wall. The second wall extends in the second direction and is furthest from the nozzle in the first direction. The third wall is located on the opposite side of the second wall in the first direction. A first inclined portion is provided between the first wall surface and the third wall surface. The wall of the third connecting channel includes a fourth wall, which extends in the second direction and is furthest from the nozzle in the first direction. The first inclined portion has a first structural surface that extends upward in a third direction between the first direction and the second direction. A second inclined portion is provided between the first wall surface and the fourth wall surface. The second inclined portion has a second structural surface that extends in a fifth direction between a fourth direction opposite to the first direction and the second direction. The first inclined portion and the second inclined portion have asymmetrical shapes.

2. The liquid ejector head as described in claim 1, characterized in that, The angle formed by the first direction and the third direction is approximately the same as the angle formed by the fourth direction and the fifth direction.

3. The liquid ejector head as described in claim 1, characterized in that, The first inclined portion has a third structural surface that extends in a sixth direction between the first direction and the third direction.

4. The liquid ejector head as described in claim 1, characterized in that, The first inclined portion has a third structural surface that extends in the first direction.

5. The liquid ejector head as described in claim 3 or 4, characterized in that, The third structural surface is disposed between the first structural surface and the third wall surface.

6. The liquid ejector head as described in claim 1, characterized in that, The wall of the first pressure chamber includes a fifth wall, which extends in the first direction and is furthest from the nozzle in the second direction. The first communicating channel has a wall surface including a sixth wall surface and a seventh wall surface. The sixth wall surface extends in the second direction and is furthest from the nozzle in a fourth direction opposite to the first direction. The seventh wall surface is located on the side opposite to the sixth wall surface in the first direction. A third inclined portion is provided between the fifth wall surface and the seventh wall surface. The third inclined portion has a fourth structural surface that extends in a fifth direction between the second direction and the fourth direction.

7. The liquid ejector head as described in claim 6, characterized in that, The first inclined portion and the third inclined portion have approximately the same shape.

8. The liquid ejector head as described in claim 6 or 7, characterized in that, It also includes a fourth connecting channel, which extends in the second direction and connects the first pressure chamber to the supply channel. The wall of the fourth connecting channel includes an eighth wall, which extends in the second direction and is furthest from the nozzle in the fourth direction. A fourth inclined portion is provided between the fifth wall surface and the eighth wall surface. The fourth inclined portion has a fifth structural surface, which extends upward from the third portion.

9. The liquid ejector head as described in claim 1, characterized in that, have: A pressure chamber base plate having a first pressure chamber and a second pressure chamber; A connecting plate is provided with the nozzle flow channel, the first connecting flow channel, the second connecting flow channel, the supply flow channel, and the discharge flow channel; A nozzle substrate having the nozzle provided thereon.

10. The liquid ejector head as described in claim 9, characterized in that, The first inclined portion is disposed on the pressure chamber substrate.

11. 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.

12. 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.

13. The liquid ejector head as described in claim 12, characterized in that, The waveforms of the first driving signal and the second driving signal are approximately the same.

14. A liquid ejector head, characterized in that, have: 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; A nozzle flow channel extends in the first direction and communicates with a nozzle that ejects liquid. 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; A supply channel that supplies liquid to the first pressure chamber; The discharge channel discharges liquid from the second pressure chamber; A third connecting channel extends in the second direction and connects the second pressure chamber with the discharge channel. The wall of the second pressure chamber includes a first wall extending in the first direction and being furthest from the nozzle in the second direction. The wall of the second communicating channel includes a second wall and a third wall. The second wall extends in the second direction and is furthest from the nozzle in the first direction. The third wall is located on the opposite side of the second wall in the first direction. A first inclined portion is provided between the first wall surface and the third wall surface. The wall of the third connecting channel includes a fourth wall, which extends in the second direction and is furthest from the nozzle in the first direction. The first inclined portion has: A first structural surface extends upward on a third direction between the first direction and the second direction; A third structural surface extends in a sixth direction between the first direction and the third direction. A second inclined portion is provided between the first wall surface and the fourth wall surface. The second inclined portion has a second structural surface that extends in a fifth direction between a fourth direction opposite to the first direction and the second direction.

15. A liquid ejection device, characterized in that, have: 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; A nozzle flow channel extends in the first direction and communicates with a nozzle that ejects liquid. 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; A supply channel that supplies liquid to the first pressure chamber; The discharge channel discharges liquid from the second pressure chamber; A third connecting channel extends in the second direction and connects the second pressure chamber with the discharge channel. The wall of the second pressure chamber includes a first wall extending in the first direction and being furthest from the nozzle in the second direction. The wall of the second communicating channel includes a second wall and a third wall. The second wall extends in the second direction and is furthest from the nozzle in the first direction. The third wall is located on the opposite side of the second wall in the first direction. A first inclined portion is provided between the first wall surface and the third wall surface. The wall of the third connecting channel includes a fourth wall, which extends in the second direction and is furthest from the nozzle in the first direction. The first inclined portion has a first structural surface that extends upward in a third direction between the first direction and the second direction. A second inclined portion is provided between the first wall surface and the fourth wall surface. The second inclined portion has a second structural surface that extends in a fifth direction between a fourth direction opposite to the first direction and the second direction. The first inclined portion and the second inclined portion have asymmetrical shapes.

Images