Liquid discharge head, image formation device and liquid discharge device

Abstract

To provide a configuration of a liquid discharge head that can adjust a fluid resistance value while suppressing an increase in size.SOLUTION: A liquid discharge head 21 comprises: a nozzle 22 which discharges a liquid; a pressure generating chamber 40 which communicates with the nozzle 22; a common liquid chamber 42 which supplies the liquid to the pressure generating chamber 40; and a fluid resistance part 41 which delivers the liquid supplied from the common liquid chamber 42 to the pressure generating chamber 40. The fluid resistance part 41 extends in a direction crossing a nozzle surface 25a where the nozzle 22 opens, and is formed in steps.SELECTED DRAWING: Figure 4

Description

[Technical field]

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

[0002] 2. Description of the Related Art A known liquid ejection head mounted on an inkjet image forming apparatus or the like applies pressure to liquid filled in a pressure generating chamber, and ejects the liquid from a nozzle communicating with the pressure generating chamber.

[0003] In such a liquid ejection head, an actuator such as a piezoelectric element is used as a means for applying pressure to the liquid in the pressure generating chamber. When applying pressure to the liquid in the pressure generating chamber, stable pressure driving by the actuator is required, but if liquid vibration occurs when refilling the pressure generating chamber with liquid, the meniscus (the interface between the liquid and air) may vibrate significantly and prevent stable pressure driving.

[0004] For this reason, in the past, a fluid resistance section with a small flow path width has been provided between the pressure generating chamber and a common liquid chamber that supplies liquid to the pressure generating chamber, thereby increasing the fluid resistance value and suppressing liquid vibrations during refilling.

[0005] The fluid resistance value of the fluid resistance portion needs to be set to an appropriate resistance value depending on the properties of the liquid, the ejection performance of the liquid, the amount of liquid supplied, and the like.

[0006] For example, Patent Document 1 (JP 2023-34649 A) ​​describes adjusting the fluid resistance value by changing the opening area and length of individual communication holes that function as fluid resistance portions.

[0007] However, simply lengthening the fluid resistance portion in order to increase the fluid resistance value results in an increase in the size of the liquid ejection head, which causes a problem of restrictions on installation space. Summary of the Invention [Problem to be solved by the invention]

[0008] Therefore, an object of the present invention is to provide a liquid ejection head configuration that is capable of adjusting the fluid resistance value while suppressing an increase in size. [Means for solving the problem]

[0009] In order to solve the above problems, the liquid ejection head of the present invention comprises a nozzle for ejecting liquid, a pressure generating chamber connected to the nozzle, a common liquid chamber for supplying liquid to the pressure generating chamber, and a fluid resistance portion for transporting liquid supplied from the common liquid chamber to the pressure generating chamber, wherein the fluid resistance portion extends in a direction intersecting a nozzle surface in which the nozzle opens and is formed in a stepped shape. Effect of the Invention

[0010] According to the present invention, it is possible to adjust the fluid resistance value while suppressing an increase in the size of the liquid ejection head. [Brief description of the drawings]

[0011] [Figure 1] 1 is a diagram showing an overall configuration of an image forming apparatus according to a first embodiment of the present invention. [Diagram 2] 2 is a control block diagram of the image forming apparatus according to the first embodiment of the present invention. FIG. [Diagram 3] FIG. 2 is a plan view of the liquid ejection unit according to the first embodiment of the present invention. [Figure 4] 1 is a cross-sectional view of a liquid ejection head according to a first embodiment of the present invention. [Diagram 5] FIG. 4 is a cross-sectional view of a liquid ejection head according to a second embodiment of the present invention. [Figure 6] FIG. 4 is a cross-sectional view of a liquid ejection head according to a third embodiment of the present invention. [Figure 7] FIG. 1 is a diagram illustrating an example of a serial type liquid ejection unit. [Figure 8] FIG. 4 is a cross-sectional view of a liquid ejection head according to a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The present invention will be described below with reference to the accompanying drawings. In each drawing for explaining the present invention, components such as members and components having the same function or shape are given the same reference numerals as far as they can be distinguished, and the description thereof will be omitted after it has been described once.

[0013] <Configuration of Image Forming Apparatus> First, a liquid ejection apparatus according to the present invention will be described taking an inkjet type image forming apparatus as an example of a liquid ejection apparatus.

[0014] FIG. 1 is a diagram showing the overall configuration of an image forming apparatus 100 according to a first embodiment of the present invention.

[0015] As shown in FIG. 1, the image forming apparatus 100 includes a sheet supplying section 1 that supplies sheets, a sheet transporting section 2 that transports the sheets, an image forming section 3 that forms an image on the sheet, a drying section 4 that dries the sheets, and a sheet collecting section 5 that collects the sheets.

[0016] The sheet supply unit 1 has a supply roller 11 and a tension adjustment mechanism 12. A long sheet S is wound around the supply roller 11 in a roll shape. When the supply roller 11 rotates, the sheet S is unwound from the supply roller 11. The tension adjustment mechanism 12 is a mechanism that adjusts the tension of the sheet S so that the sheet S is supplied with a constant tension. Specifically, the tension adjustment mechanism 12 has a plurality of rollers around which the sheet S is stretched. By moving some of the plurality of rollers that the tension adjustment mechanism 12 has, the tension of the sheet S is adjusted, and the sheet S is supplied with a constant tension.

[0017] The sheet conveying section 2 has a plurality of conveying rollers 15 as a conveying means for conveying the sheet S. The sheet conveying means may be a conveying belt or the like in addition to the conveying rollers 15. With the sheet S stretched across each of the conveying rollers 15, the conveying rollers 15 rotate, whereby the sheet S is conveyed to the image forming section 3.

[0018] The image forming section 3 has a liquid ejection unit 13 and a transport guide member 14. The liquid ejection unit 13 is a means for ejecting liquid such as ink onto the sheet S. The transport guide member 14 is a guide member disposed below the liquid ejection unit 13 so as to face the same. When the sheet S is transported onto the transport guide member 14, the sheet S is guided along the transport guide member 14. Then, an image is formed on the sheet S by ejecting liquid from the liquid ejection unit 13 onto the sheet S on the transport guide member 14.

[0019] The drying section 4 has a heating roller 16 that heats the sheet S. The heating roller 16 is a cylindrical roller having a heating source such as a halogen heater inside. The sheet S is heated and dried by being conveyed while being in contact with the outer circumferential surface of the heating roller 16. The heating means for heating the sheet S may be a contact type heating means such as the heating roller 16, or a non-contact type heating means such as a hot air generator that blows hot air onto the sheet S.

[0020] The sheet collection section 5 has a collection roller 17 and a tension adjustment mechanism 18. When the sheet S is transported to the sheet collection section 5, the collection roller 17 winds up the sheet S into a roll and collects it. The tension adjustment mechanism 18 has multiple rollers, similar to the tension adjustment mechanism 12 of the sheet supply section 1. The tension of the sheet S is adjusted by moving some of the multiple rollers of the tension adjustment mechanism 18, and the sheet S is wound up by the collection roller 17 with a constant tension.

[0021] <Control configuration of image forming apparatus> FIG. 2 is a control block diagram of the image forming apparatus 100 according to the first embodiment of the present invention.

[0022] As shown in FIG. 2, image forming apparatus 100 includes a CPU (Central Processing Unit) 501, a ROM (Read Only Memory) 502, a RAM (Random Access Memory) 503, a NVRAM (Non-Volatile Random Access Memory) 504, an external device connection I / F 505, a network I / F 506, a bus line 507, and an operation panel 508.

[0023] The CPU 501 controls the overall operation of the image forming apparatus 100. Specifically, the CPU 501 controls the ejection operation of the liquid ejection unit 13, the rotation speeds of the supply roller 11, the recovery roller 17, and the transport roller 15, the temperature of the heating roller 16, and the tension adjustment operation of the tension adjustment mechanisms 12 and 18. The ROM 502 stores programs used to drive the CPU 501, such as the IPL. The RAM 503 is used as a work area for the CPU 501. The NVRAM 504 stores various data such as programs, and retains the various data even when the power to the image forming apparatus 100 is cut off.

[0024] The external device connection I / F 505 is connected to a PC (Personal Computer) via a USB (Universal Serial Bus) cable or the like, and communicates control signals and data of images to be printed with the PC. The network I / F 506 is an interface for communicating data using a communication network such as the Internet. The bus line 507 is an address bus and a data bus for electrically connecting each component such as the CPU 501.

[0025] The operation panel 508 displays current setting values ​​and a selection screen, etc., and is configured with a touch panel that receives input from an operator, an alarm lamp, etc. The CPU 501 controls various operations of the image forming apparatus 100 based on information such as image information, sheet conveying speed, and sheet type input through the operation panel 508.

[0026] <Configuration of liquid ejection unit> FIG. 3 is a plan view of the liquid ejection unit 13 according to the first embodiment of the present invention.

[0027] 3, the liquid ejection unit 13 is configured with full line type head arrays 20 for four colors, such as black, cyan, magenta, and yellow, in that order from the upstream side in the sheet conveying direction A in which the sheet S is conveyed. Each head array 20 has a base portion 23 and a plurality of liquid ejection heads 21 held by the base portion 23. Each liquid ejection head 21 has a plurality of nozzles 22 that eject liquid. In the line type head array 20, the position of each liquid ejection head 21 is fixed at a position facing the sheet S, so that when the sheet S is conveyed, liquid is ejected from each liquid ejection head 21 onto the conveyed sheet S, thereby forming an image on the sheet S.

[0028] In this example, the multiple liquid ejection heads 21 extend long in the sheet width direction B perpendicular to the sheet transport direction A, and are arranged in a staggered manner while being offset from one another in the sheet transport direction A. Among the nozzles 22 of the liquid ejection heads 21 that are arranged offset from one another, the nozzles 22 at the ends of the nozzle rows are arranged at positions that overlap one another in the sheet transport direction A. For this reason, an image can be formed across the entire image formation area on the sheet S in the sheet width direction B. Note that the arrangement, number, and color of the ejected liquid of the liquid ejection heads 21 are not limited to the example shown in FIG.

[0029] <Configuration of Liquid Ejection Head> 4 is a cross-sectional view of the liquid ejection head 21 according to the first embodiment of the present invention. Here, a cross section of the liquid ejection head 21 taken at the position of the nozzle 22 in the short side direction is shown.

[0030] As shown in FIG. 4, the liquid ejection head 21 includes a nozzle plate 25, a flow path plate 26, a frame member 27, a vibration plate 28, a piezoelectric actuator 30, and a flexible wiring member 29.

[0031] The nozzle plate 25 is a plate-shaped member having a plurality of nozzles 22 .

[0032] The flow passage plate 26 is a plate-like member that forms the pressure generating chamber 40 and the fluid resistance portion 41 by being laminated in plurality. The flow passage plate 26 has a liquid chamber hole 26a that forms the pressure generating chamber 40 and a flow passage hole 26b that forms the fluid resistance portion 41. The liquid chamber holes 26a of the plurality of flow passage plates 26 that are laminated on each other overlap and communicate with each other to form the pressure generating chamber 40. Also, the flow passage holes 26b of each flow passage plate 26 overlap and communicate with each other to form the fluid resistance portion 41. A plurality of pressure generating chambers 40 and fluid resistance portions 41 are provided across the longitudinal direction of the liquid ejection head 21 (the direction perpendicular to the paper surface in FIG. 4). Also, a nozzle plate 25 is joined to the laminated flow passage plates 26, so that a part of the wall surface of the pressure generating chamber 40 is formed by the nozzle plate 25. Therefore, the pressure generating chamber 40 communicates with the nozzle 22.

[0033] The frame member 27 is a member that also serves as a frame for the liquid ejection head 21, and forms a common liquid chamber 42. The common liquid chamber 42 communicates with each pressure generating chamber 40 via a fluid resistance portion 41.

[0034] The vibration plate 28 is a deformable plate-like member. The vibration plate 28 is joined to the flow path plate 26 on the opposite side to the nozzle plate 25 across the pressure generating chamber 40. Therefore, the wall surface of the pressure generating chamber 40 on the opposite side to the nozzle plate 25 side is formed by the vibration plate 28. The vibration plate 28 is also interposed between the stacked flow path plates 26, and forms part of the fluid resistance portion 41.

[0035] The piezoelectric actuator 30 includes a base substrate 31 and a piezoelectric element 32 bonded to the base substrate 31. The piezoelectric element 32 is a laminated piezoelectric element in which piezoelectric materials and internal electrodes are alternately laminated. The internal electrodes of the piezoelectric element 32 are connected to a flexible wiring member 29 via external electrodes (end surface electrodes). In addition, the surface of the piezoelectric element 32 opposite to the surface bonded to the base substrate 31 is bonded to the surface of the vibration plate 28 opposite to the surface on the pressure generating chamber 40 side.

[0036] In the liquid ejection head 21 having such a configuration, when a voltage lower than a reference potential (intermediate potential) is applied to the piezoelectric element 32, the piezoelectric element 32 contracts in its lamination direction, and the vibration plate 28 deforms so as to bend toward the opposite side to the nozzle 22. As a result, the volume of the pressure generating chamber 40 expands, generating a negative pressure in the pressure generating chamber 40, and liquid flows into the pressure generating chamber 40 from the common liquid chamber 42.

[0037] Next, when the voltage applied to the piezoelectric element 32 is increased and the piezoelectric element 32 expands in its stacking direction, the vibration plate 28 deforms toward the nozzle 22, contracting the volume of the pressure generating chamber 40. As a result, the liquid in the pressure generating chamber 40 is pressurized, and the liquid is ejected from the nozzle 22.

[0038] Thereafter, by returning the voltage applied to the piezoelectric element 32 to the reference potential, the vibration plate 28 is restored to its initial position, and the volume of the pressure generating chamber 40 expands, generating negative pressure. As a result, liquid is supplied from the common liquid chamber 42 into the pressure generating chamber 40, filling it. At this time, the liquid passes through the fluid resistance portion 41, suppressing liquid vibration during refilling. The fluid resistance portion 41 has a smaller cross-sectional area in a direction perpendicular to the liquid flow direction than the pressure generating chamber 40 and the common liquid chamber 42. Therefore, when the liquid tries to pass through the fluid resistance portion 41, the fluid resistance value of the liquid increases, suppressing liquid vibration during refilling. As a result, the vibration of the meniscus surface of the nozzle 22 is attenuated. Then, after the meniscus surface is stabilized, the operation proceeds to the next liquid ejection.

[0039] <Configuration of fluid resistance part> Here, in the configuration according to the first embodiment of the present invention, the fluid resistance portion 41 is formed in a stepped shape. More specifically, the positions of the flow path holes 26b adjacent to each other in the stacking direction of the stacked flow path plates 26 are shifted in a direction perpendicular to the stacking direction, thereby forming the fluid resistance portion 41 in a stepped shape. Note that the "stacking direction" here refers to the direction in which the multiple flow path plates 26 are stacked, in other words, the direction perpendicular to the nozzle surface 25a of the nozzle plate 25 in which the nozzles 22 open.

[0040] In this way, in the first embodiment of the present invention, the fluid resistance portions 41 are formed in a stepped shape, and are arranged so as to extend alternately in a direction perpendicular to and parallel to the nozzle face 25a. Therefore, in the first embodiment of the present invention, it is possible to prevent the liquid ejection head 21 from becoming large in size, compared to a configuration having a linear fluid resistance portion 41 as shown in FIG.

[0041] That is, in the configuration shown in FIG. 8, the linear fluid resistance portion 41 is arranged to extend in a direction parallel to the nozzle surface 25a. Therefore, if the fluid resistance portion 41 is simply lengthened in order to increase the fluid resistance value, the liquid ejection head 21 will be enlarged in the direction parallel to the nozzle surface 25a by the amount of the length of the fluid resistance portion 41. In contrast, in the first embodiment of the present invention, the fluid resistance portion 41 is formed in a stepped shape that alternately extends in a direction perpendicular to the nozzle surface 25a and in a direction parallel to the nozzle surface 25a, so that the enlargement in the direction parallel to the nozzle surface 25a can be suppressed. In addition, by forming the fluid resistance portion 41 in a stepped shape, the fluid resistance value can be effectively increased and the length of the fluid resistance portion 41 itself can be shortened compared to the case where the linear fluid resistance portion 41 is simply lengthened. Therefore, the liquid ejection head 21 can be made smaller in size. Moreover, in the case of the first embodiment of the present invention, the fluid resistance section 41 can be easily formed in a stepped shape simply by shifting the positions of the flow path holes 26b of the stacked flow path plates 26, so that the fluid resistance value can be appropriately and inexpensively adjusted depending on the properties of the liquid, the liquid ejection performance, the amount of liquid supplied, etc.

[0042] <Configuration of other embodiments> Next, another embodiment of the present invention will be described. Below, differences from the first embodiment of the present invention will be mainly described, and descriptions of the same parts will be omitted as appropriate.

[0043] Second embodiment of the present invention FIG. 5 is a cross-sectional view of a liquid ejection head 21 according to a second embodiment of the present invention.

[0044] 5, the fluid resistance portion 41 is formed in a stepped shape extending in a diagonal direction with respect to the nozzle surface 25a. In this case, the misalignment direction of the flow path holes 26b adjacent to each other in the stacking direction is continuously set to the same direction, so that the fluid resistance portion 41 is generally diagonal with respect to the nozzle surface 25a.

[0045] Third embodiment of the present invention FIG. 6 is a cross-sectional view of a liquid ejection head 21 according to a third embodiment of the present invention.

[0046] 6, the fluid resistance portion 41 is formed in a stepped S-shape. In this case, the misalignment direction of the flow path holes 26b adjacent to each other in the stacking direction is partially opposite to each other, so that the fluid resistance portion 41 is generally S-shaped.

[0047] In this way, the fluid resistance portion 41 according to the embodiment of the present invention may be shaped to extend in a diagonal direction relative to the nozzle surface 25a as shown in FIG. 5, or may be S-shaped as shown in FIG. 6. Regardless of the shape of the fluid resistance portion 41, the fluid resistance value can be increased while suppressing the increase in size of the liquid ejection head 21 compared to the configuration shown in FIG. 8. That is, the fluid resistance portion 41 according to the present invention may have at least a portion extending in a direction intersecting the nozzle surface 25a and formed in a stepped shape. Note that the "direction intersecting the nozzle surface 25a" here includes a direction perpendicular to the nozzle surface 25a as well as a direction oblique to the nozzle surface 25a.

[0048] Furthermore, in each embodiment shown in Figures 4, 5, and 6, adjacent flow path holes 26b are shifted horizontally in each figure (short direction of the liquid ejection head 21) to form a step-like fluid resistance portion 41, but the direction in which the flow path holes 26b are shifted is not limited to the horizontal direction and may be a direction perpendicular to the paper surface of each figure (longitudinal direction of the liquid ejection head 21).

[0049] Further, the present invention is not limited to the line type liquid ejection unit 13 as shown in Fig. 3, but can also be applied to a serial type liquid ejection unit 60 as shown in Fig. 7. Hereinafter, the configuration and operation of the serial type liquid ejection unit 60 will be briefly described with reference to Fig. 7.

[0050] A serial type liquid ejection unit 60 shown in FIG. 7 includes a carriage 62 on which a liquid ejection head 61 is mounted, a guide member 63 for guiding the carriage 62 in the sheet width direction B, and a drive device 64 for moving the carriage 62.

[0051] The driving device 64 includes, for example, a motor 65 as a driving source, a driving pulley 66, a driven pulley 67, and a timing belt 68. When the motor 65 is driven and the driving pulley 66 rotates, the timing belt 68 stretched around the pulleys 66 and 67 moves in an orbit, whereby the carriage 62 moves in the sheet width direction B along the guide member 63.

[0052] As the carriage 62 moves in the sheet width direction B, liquid is ejected from the liquid ejection head 61 onto the stationary sheet S, forming an image for one line on the sheet S. Then, after the image for one line has been formed, the sheet S advances a predetermined amount, and at that position the carriage 62 moves again while ejecting liquid from the liquid ejection head 61, forming an image for the next line. Thereafter, the sheet S is similarly transported intermittently by a predetermined amount, and the reciprocating movement of the carriage 62 and the ejection of liquid are repeated, forming an image on the sheet S.

[0053] By applying the present invention to such a serial type liquid ejection unit 60, it becomes possible to adjust the fluid resistance value while suppressing an increase in size of the liquid ejection head 61. That is, by making the fluid resistance portion 41 step-shaped extending in a direction intersecting the nozzle face 25a, rather than being linear extending only in a direction parallel to the nozzle face 25a, it is possible to effectively increase the fluid resistance value while suppressing the length of the fluid resistance portion 41, and therefore it becomes possible to miniaturize the liquid ejection head 61.

[0054] Furthermore, the "liquid ejection device" according to the present invention includes various liquid ejection devices, as long as the device has a liquid ejection head and ejects liquid onto a sheet by driving the liquid ejection head, in addition to an inkjet type image forming device, which is an example of a liquid ejection device. Therefore, the "liquid ejection device" according to the present invention is not limited to a device that visualizes meaningful images such as characters and figures using ejected liquid. For example, the "liquid ejection device" also includes a device that forms a pattern that has no meaning in itself, a device that creates a three-dimensional image, and even a treatment liquid ejection device that ejects a treatment liquid onto the surface of a sheet for the purpose of modifying the surface of the sheet.

[0055] Furthermore, the "liquid ejection device" according to the present invention may include a post-processing device in addition to means for feeding, conveying, and discharging a sheet and a pre-processing device. Furthermore, the "liquid ejection device" may eject liquid while moving a liquid ejection head, or may eject liquid while keeping the liquid ejection head stationary. Specific examples include a line-type liquid ejection device as shown in FIG. 3 and a serial-type liquid ejection device as shown in FIG. 7.

[0056] Furthermore, the "sheet" onto which the liquid is ejected includes any material to which the liquid can adhere at least temporarily, and includes any material to which the liquid can adhere and stick, and any material to which the liquid can adhere and penetrate. Specific examples include recording media such as paper, recording paper, film, and cloth, and electronic boards. The "sheet" may be made of any material to which the liquid can adhere even temporarily, such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, and ceramics. The "sheet" may be a long sheet wound into a roll (such as roll paper), or a sheet cut to a predetermined size in the sheet transport direction (such as cut paper).

[0057] Furthermore, the "liquid ejection device" according to the present invention is not limited to a device that ejects liquid onto an object onto which the liquid can be attached, but may be a device that ejects liquid into air or liquid.

[0058] The "liquid" discharged by the "liquid discharge device" according to the present invention may have a viscosity or surface tension that allows it to be discharged from a liquid discharge head, and is not particularly limited. However, it is preferable that the viscosity of the liquid is 30 mPa·s or less at room temperature and pressure, or by heating or cooling. More specifically, the liquid may be a solution, suspension, emulsion, etc., containing a solvent such as water or an organic solvent, a colorant such as a dye or a pigment, a functionalizing material such as a polymerizable compound, a resin, or a surfactant, a biocompatible material such as DNA, an amino acid, a protein, or calcium, an edible material such as a natural dye, etc. These can be used for applications such as inkjet ink, a surface treatment liquid, a component of an electronic element or a light-emitting element, a liquid for forming an electronic circuit resist pattern, and a material liquid for three-dimensional modeling.

[0059] To summarize the above-described aspects of the present invention, the present invention includes at least the following aspects.

[0060] [First aspect] The first aspect is a liquid ejection head comprising a nozzle for ejecting liquid, a pressure generating chamber connected to the nozzle, a common liquid chamber for supplying liquid to the pressure generating chamber, and a fluid resistance section for directing liquid supplied from the common liquid chamber to the pressure generating chamber, the fluid resistance section extending in a direction intersecting a nozzle face in which the nozzle opens and being formed in a stepped shape.

[0061] [Second aspect] In a second aspect, in the first aspect, the fluid resistance portion is formed by stacking a plurality of flow path plates, each of which has a flow path hole that allows liquid to pass through, and the fluid resistance portion is formed in a stepped shape by shifting the positions of the flow path holes adjacent to each other in the stacking direction of the flow path plates in a direction perpendicular to the stacking direction.

[0062] [Third aspect] A third aspect is based on the first or second aspect, wherein the fluid resistance portions are formed in a stepped shape and extend alternately in a direction perpendicular to and parallel to the nozzle surface.

[0063] [Fourth aspect] In a fourth aspect, in the second aspect, the fluid resistance portion is formed in a stepped shape extending in an oblique direction with respect to the nozzle face such that the misalignment direction of the flow path holes relative to each other is continuously in the same direction.

[0064] [Fifth aspect] In a fifth aspect, in the second aspect, the flow path holes are offset in positions in partially opposite directions, and the fluid resistance portion is formed in a stepped S-shape.

[0065] [Sixth aspect] A sixth aspect is an image forming apparatus including the liquid ejection head according to any one of the first to fifth aspects.

[0066] [Seventh aspect] A seventh aspect is a liquid ejection device including the liquid ejection head according to any one of the first to fifth aspects. [Explanation of symbols]

[0067] 21 Liquid ejection head 22 Nozzle 25 Nozzle plate 25a Nozzle surface 26 Flow Plate 26b Flow passage hole 40 Pressure chamber 41 Fluid resistance section 42 Common liquid chamber 100 Image forming device (liquid ejection device) [Prior art documents] [Patent documents]

[0068] [Patent Document 1] JP 2023-34649 A

Claims

1. A nozzle for discharging a liquid; a pressure generating chamber communicating with the nozzle; a common liquid chamber for supplying liquid to the pressure generating chamber; a fluid resistance portion that transfers the liquid supplied from the common liquid chamber to the pressure generating chamber, The liquid ejection head is characterized in that the fluid resistance portion extends in a direction intersecting a nozzle face in which the nozzles are opened, and is formed in a stepped shape.

2. The fluid resistance portion is formed by stacking a plurality of flow path plates, The flow path plate has flow path holes for passing a liquid, 2. The liquid ejection head according to claim 1, wherein the fluid resistance portion is formed in a stepped shape by shifting the positions of the flow path holes adjacent to each other in a stacking direction of the flow path plates in a direction perpendicular to the stacking direction.

3. The liquid ejection head according to claim 1 , wherein the fluid resistance portion is formed in a stepped shape and extends alternately in a direction perpendicular to and parallel to the nozzle surface.

4. 3. The liquid ejection head according to claim 2, wherein the fluid resistance portion is formed in a stepped shape extending in an oblique direction with respect to the nozzle surface, so that the misalignment direction of the flow path holes relative to each other is continuously in the same direction.

5. 3. The liquid ejection head according to claim 2, wherein the fluid resistance portion is formed in a stepped S-shape such that the misalignment directions of the flow path holes are partially opposite to each other.

6. An image forming apparatus comprising the liquid ejection head according to claim 1 .

7. A liquid ejection apparatus comprising the liquid ejection head according to claim 1 .

Images