Liquid ejection device

Abstract

To provide a liquid discharge head capable of improving cleaning efficiency by wiping and reducing damage, and a device that discharges liquid.SOLUTION: A liquid discharge head includes a nozzle member 101 including a nozzle 110 that discharges liquid. The nozzle member 101 includes a deformable thin layer member 111 including an opening 111a forming the nozzle 110, and a piezoelectric element 112 arranged in the periphery of the opening 111a. In a state where a voltage is not applied to the piezoelectric element 112, in the nozzle member 101, a peripheral part 130 of the nozzle member 110 warps with respect to a discharge side plane of the nozzle member 101.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention ,liquid This relates to a device for expelling bodies. [Background technology]

[0002] As a liquid ejection head, for example, there is one that includes a nozzle member in which a piezoelectric element that bends and deforms is provided in a deformable thin layer member having openings that form nozzles for ejecting liquid.

[0003] Conventionally, a device has been known in which, when ejecting liquid, a piezoelectric element is driven to deform the peripheral portion of an opening in a thin member so that it warps in the liquid ejection direction, or warps in the opposite direction to the liquid ejection direction, thereby controlling the liquid ejection direction (Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-214851 Summary of the Invention [Problem to be solved by the invention]

[0005] In devices that use liquid ejection heads, a wiping operation is performed using a wiping member to clean the ejection surface. It is required to improve the cleaning efficiency of the ejection surface and reduce damage caused by this wiping.

[0006] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to improve the cleaning efficiency and reduce damage caused by wiping the ejection surface. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention Liquid ejection device teeth, a nozzle member having a nozzle for discharging a liquid; The nozzle member is a deformable thin film member having an opening that forms the nozzle; an electromechanical transducer disposed around the opening, When no voltage is applied to the electromechanical transducer, the angle formed between the surface of the nozzle member facing the liquid chamber through which the nozzle communicates and the side wall surface of the liquid chamber is less than 90°. a liquid ejection head; a wiping member that wipes the ejection surface of the liquid ejection head; and means for applying a voltage to the electromechanical converter of the liquid ejection head so that, when the wiping member wipes the ejection surface, an angle formed between a surface of the nozzle member facing a liquid chamber through which the nozzle communicates and a side wall surface of the liquid chamber becomes larger than an angle when no voltage is applied to the electromechanical converter. The composition was as follows. [Effects of the Invention]

[0008] According to the present invention, it is possible to improve the cleaning efficiency and reduce damage caused by wiping the ejection surface. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is an explanatory diagram of a device for discharging liquid according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view illustrating the operation of the embodiment. [Figure 3] FIG. [Figure 4] FIG. 10 is an explanatory diagram of a liquid ejecting device according to a second embodiment of the present invention. [Figure 5] FIG. 2 is a cross-sectional view illustrating the operation of the embodiment. [Figure 6] FIG. [Figure 7] FIG. 10 is an explanatory diagram of a liquid ejecting device according to a third embodiment of the present invention. [Figure 8] 10 is a cross-sectional explanatory view of a liquid ejection head of Comparative Example 1, which is provided for explaining the operation of the embodiment. FIG. [Figure 9] 5A to 5C are cross-sectional explanatory views illustrating an example of a manufacturing process for a liquid ejection head. [Figure 10]FIG. 10 is an explanatory cross-sectional view illustrating a step subsequent to FIG. 9. [Figure 11] 10 is a cross-sectional explanatory view illustrating another example of a liquid ejection head according to Comparative Example 1 in which there is no warping in the peripheral portion of the nozzle. FIG. [Figure 12] 1 is a plan view illustrating a main part of an example of a device for discharging a liquid according to the present invention; [Figure 13] FIG. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. First, a first embodiment of the present invention will be described with reference to Fig. 1. Fig. 1 is an explanatory diagram of a device for discharging liquid according to the first embodiment.

[0011] The liquid ejection device 1 includes a liquid ejection head 100 according to the present invention.

[0012] The liquid ejection head 100 has a nozzle member 101 having nozzles 110 for ejecting liquid, and a liquid chamber forming member 102 that forms a liquid chamber 120 to which the nozzles 110 communicate.

[0013] The nozzle member 101 has a thin layer member (nozzle substrate) 111 which serves as a deformable nozzle plate / vibration plate having openings 111a which form nozzles 110 for ejecting liquid, and a piezoelectric element 112 which serves as an electromechanical transducer and is arranged around the openings 111a of the thin layer member 111. The thin layer member 111 has a laminated structure of a vibration layer 504 and an insulating layer 503 which also has a stress adjustment function.

[0014] The piezoelectric element 112 is formed by sequentially laminating a lower electrode 113, a piezoelectric film 114 as an electromechanical transducer film, and an upper electrode 115 on one surface (the surface of the vibration layer 504) of the thin layer member 111. A protective film 116 that covers the piezoelectric element 112 is provided.

[0015] A liquid-repellent film 117 having liquid repellency is formed on the surface of the protective film 116. The surface of the liquid-repellent film 117 serves as an ejection surface 118.

[0016] The liquid chamber forming member 102 forms a liquid chamber 120 to which the nozzle 110 of the nozzle member 101 (the opening 111a of the thin layer member 111) communicates.

[0017] Here, in the liquid ejection head 100, when no voltage is applied to the piezoelectric element 112, the nozzle member 101 has a peripheral portion 130 of the nozzle 110 warped relative to the ejection-side plane of the nozzle member 101. In other words, the peripheral portion 130 of the nozzle 110 warps relative to the main plane of the nozzle member 101 (the surface having a relatively larger area than the other surfaces).

[0018] In this embodiment, the peripheral portion 130 of the nozzle 110 is a partial region around the nozzle 110 within the portion of the nozzle member 101 that faces the liquid chamber 120. The peripheral portion 130 of the nozzle 110 is warped in the direction opposite to the liquid ejection direction (toward the liquid chamber 120). In this embodiment, the warping of the peripheral portion 130 of the nozzle 110 is adjusted by the insulating layer 503 that constitutes the thin layer member 111 and also serves as a stress adjustment function.

[0019] The liquid ejection device 1 is equipped with a maintenance and recovery mechanism 200 including a wiping member 201 that wipes the ejection surface 118 of the liquid ejection head 100. The wiping member 201 wipes and cleans the ejection surface 118 by moving the wiping member 201 relative to the liquid ejection head 100 using a wiping mechanism drive control means 202.

[0020] The liquid ejection device 1 includes a voltage application means 300 that applies a voltage to the piezoelectric element 112 of the liquid ejection head 100. The voltage application means 300 can apply a predetermined voltage (referred to as a first voltage) that drives the piezoelectric element 112 so that the peripheral portion 130 of the nozzle 110 of the nozzle member 101 warps in the liquid ejection direction.

[0021] In this embodiment, the voltage application means 300 applies a first voltage to the piezoelectric element 112 corresponding to the nozzle 110 having residual liquid adhering to the peripheral portion 130 of the ejection surface 118 when the wiping operation is performed by the wiping member 201.

[0022] Next, the operation of this embodiment will be described with reference to Figures 2 and 3. Figures 2 and 3 are cross-sectional explanatory views provided for explaining the operation.

[0023] The liquid ejecting device 1 performs an operation to maintain and restore the state of the liquid ejection head 100 at a predetermined timing using the maintenance and recovery mechanism 200. At this time, the wiping mechanism drive control means 202 of the maintenance and recovery mechanism 200 moves the wiping member 201 relative to the ejection surface 118 of the liquid ejection head 100, thereby wiping and cleaning the ejection surface 118 of the liquid ejection head 100.

[0024] Here, for the nozzle 110 with residual liquid 400 adhering to the ejection surface 118, the voltage application means 300 applies a first voltage to the piezoelectric element 112. As a result, as shown in FIG. 2(a), the peripheral portion 130 of the nozzle 110 is displaced so as to be warped in the liquid ejection direction.

[0025] 2(b), when the wiping member 201 wipes the ejection surface 118, the pressure with which the wiping member 201 contacts the ejection surface 118 increases in the region of the peripheral portion 130 of the nozzle 110, thereby reliably wiping and removing the residual liquid 400. This allows cleaning to be performed with fewer wiping operations, improving cleaning efficiency.

[0026] In contrast, for nozzles 110 where no residual liquid 400 is attached to the ejection surface 118, the voltage application means 300 does not apply the first voltage to the piezoelectric element 112. As a result, as shown in Figure 3(a), the peripheral portion 130 of the nozzle 110 where no residual liquid 400 is attached to the ejection surface 118 remains warped in the direction opposite to the liquid ejection direction.

[0027] 3(b), when the wiping member 201 wipes the ejection surface 118, the wiping member 201 does not come into contact with the ejection surface 118, or the contact pressure is low, in the region of the peripheral portion 130 of the nozzle 110. This reduces damage to the liquid-repellent film 117 caused by the wiping action.

[0028] Next, a second embodiment of the present invention will be described with reference to Fig. 4. Fig. 4 is an explanatory diagram of a device for discharging liquid according to the second embodiment.

[0029] The liquid ejection device 1 includes a liquid ejection head 100 according to the present invention.

[0030] The liquid ejection head 100 has a nozzle member 101 having nozzles 110 for ejecting liquid, and a liquid chamber forming member 102 that forms a liquid chamber 120 to which the nozzles 110 communicate.

[0031] The nozzle member 101 has a thin layer member (nozzle substrate) 111 which serves as a deformable nozzle plate / vibration plate having an opening 111a which forms a nozzle 110 for ejecting liquid, and a piezoelectric element 112 which serves as an electromechanical transducer and is arranged around the opening 111a of the thin layer member 111.

[0032] The piezoelectric element 112 is formed by sequentially laminating a lower electrode 113, a piezoelectric film 114 as an electromechanical transducer film, and an upper electrode 115 on one surface of a thin layer member 111. A protective film 116 that covers the piezoelectric element 112 is provided.

[0033] A liquid-repellent film 117 having liquid repellency is formed on the surface of the protective film 116. The surface of the liquid-repellent film 117 serves as an ejection surface 118.

[0034] The liquid chamber forming member 102 forms a liquid chamber 120 to which the nozzle 110 of the nozzle member 101 (the opening 111a of the thin layer member 111) communicates.

[0035] Here, in the liquid ejection head 100, when no voltage is applied to the piezoelectric element 112, the nozzle member 101 has a peripheral portion 130 of the nozzle 110 warped relative to the ejection-side plane of the nozzle member 101. In other words, the peripheral portion 130 of the nozzle 110 warps relative to the main plane of the nozzle member 101 (the surface having a relatively larger area than the other surfaces).

[0036] In this embodiment, the peripheral portion 130 of the nozzle 110 is a partial region around the nozzle 110 within the portion of the nozzle member 101 that faces the liquid chamber 120. The peripheral portion 130 of the nozzle 110 is warped in the liquid ejection direction (the direction opposite to the liquid chamber 120). Again, the warping of the peripheral portion 130 of the nozzle 110 in this embodiment is adjusted by the insulating layer 503 that also serves as a stress adjustment function and that constitutes the thin layer member 111.

[0037] The liquid ejection device 1 is equipped with a maintenance and recovery mechanism 200 including a wiping member 201 that wipes the ejection surface 118 of the liquid ejection head 100. The wiping member 201 wipes and cleans the ejection surface 118 by moving the wiping member 201 relative to the liquid ejection head 100 using a wiping mechanism drive control means 202.

[0038] The liquid ejection device 1 includes a voltage application means 300 that applies a voltage to the piezoelectric element 112 of the liquid ejection head 100. The voltage application means 300 can apply a predetermined voltage (referred to as a second voltage) that drives the piezoelectric element 112 so that the peripheral portion 130 of the nozzle 110 of the nozzle member 101 warps in the direction opposite to the liquid ejection direction (towards the liquid chamber 120).

[0039] In this embodiment, when the wiping operation is performed by the wiping member 201, the voltage application means 300 applies a second voltage to the piezoelectric element 112 corresponding to the nozzle 110 to which no residual liquid adheres on the peripheral portion 130 of the ejection surface 118.

[0040] Next, the operation of this embodiment will be described with reference to Figures 5 and 6. Figures 5 and 6 are cross-sectional explanatory views provided for explaining the operation.

[0041] The liquid ejecting device 1 performs an operation to maintain and restore the state of the liquid ejection head 100 at a predetermined timing using the maintenance and recovery mechanism 200. At this time, the wiping mechanism drive control means 202 of the maintenance and recovery mechanism 200 moves the wiping member 201 relative to the ejection surface 118 of the liquid ejection head 100, thereby wiping and cleaning the ejection surface 118 of the liquid ejection head 100.

[0042] Here, for the nozzle 110 with residual liquid 400 adhering to the ejection surface 118, the voltage application means 300 does not apply the second voltage to the piezoelectric element 112. As a result, as shown in Figure 5(a), the peripheral portion 130 of the nozzle 110 remains warped in the direction opposite to the liquid ejection direction.

[0043] 5(b), when the wiping member 201 wipes the ejection surface 118, the pressure with which the wiping member 201 contacts the ejection surface 118 increases in the region of the peripheral portion 130 of the nozzle 110, thereby reliably wiping and removing the residual liquid 400. This allows cleaning to be performed with fewer wiping operations, improving cleaning efficiency.

[0044] On the other hand, for nozzles 110 where no residual liquid 400 is attached to the ejection surface 118, a second voltage is applied to the piezoelectric element 112 by the voltage application means 300. As a result, as shown in Figure 6(a), the peripheral portion 130 of the nozzle 110 where no residual liquid 400 is attached to the ejection surface 118 is displaced to a state where it is warped in the direction opposite to the liquid ejection direction.

[0045] 6(b), when the wiping member 201 wipes the ejection surface 118, the wiping member 201 does not come into contact with the ejection surface 118, or the contact pressure is small, in the region of the peripheral portion 130 of the nozzle 110. This reduces damage to the liquid-repellent film 117 caused by the wiping action.

[0046] Next, a third embodiment of the present invention will be described with reference to Fig. 7. Fig. 7 is an explanatory diagram of a device for discharging liquid according to the third embodiment.

[0047] As in the first embodiment, when no voltage is applied to the piezoelectric element 112 of the liquid ejection head 100, the peripheral portion 130 of the nozzle 110 of the nozzle member 101 is warped in the direction opposite to the liquid ejection direction relative to the ejection side plane of the nozzle member 101.

[0048] In this embodiment, the peripheral portion 130 of the nozzle 110 is the entire area of ​​the portion of the nozzle member 101 that faces the liquid chamber 120. As described above, the peripheral portion 130 of the nozzle 110 is warped in the direction opposite to the liquid ejection direction (toward the liquid chamber 120).

[0049] Therefore, the angle θ formed between the surface 101a of the nozzle member 101 on the liquid chamber 120 side and the side wall surface 120a of the liquid chamber 120 is less than 90°.

[0050] In this embodiment as well, when the wiping member 201 performs a wiping operation, for nozzles 110 having residual liquid adhering to the peripheral portion 130 of the nozzle 110, the peripheral portion 130 is deflected in the liquid ejection direction.

[0051] Next, the operation of this embodiment will be described with reference to Comparative Example 1 in FIG.

[0052] In Comparative Example 1, the angle θ formed between the surface 101a of the nozzle member 101 on the liquid chamber 120 side and the side wall surface 120a of the liquid chamber 120 is set to 90° or more.

[0053] In a liquid ejection head in which a piezoelectric element 112 is arranged in the peripheral portion 130 of the nozzle 110 of the nozzle member 101 and liquid is ejected by vibrating the nozzle member 101, as in this embodiment and comparative example 1, stress is applied to the joint between the nozzle member 101 and the liquid chamber forming member 102.

[0054] In other words, when a liquid ejection operation is performed, a voltage is applied to the piezoelectric element 112, causing the peripheral portion 130 of the nozzle 110 to displace in a direction that increases the angle θ formed by the joint between the surface 101a of the nozzle member 101 facing the liquid chamber 120 and the side wall surface 120a of the liquid chamber 120.

[0055] Here, as in Comparative Example 1 shown in Figure 8, when the angle θ formed between the surface 101a of the nozzle member 101 facing the liquid chamber 120 and the side wall surface 120a of the liquid chamber 120 is 90° or more, the angle θ will exceed 90° when the liquid ejection operation is performed.

[0056] In this way, when the angle θ exceeds 90°, tensile stress is applied to the nozzle member 101 at the joint. If tensile stress is repeatedly applied in conjunction with the liquid ejection operation, it can cause cracks in the thin layer member 111 of the nozzle member 101, and become a factor in shortening the life of the liquid ejection head 100.

[0057] Therefore, as in this embodiment, the peripheral portion 130 of the nozzle 110 is warped so that the angle θ formed between the surface 101a of the nozzle member 101 facing the liquid chamber 120 and the side wall surface 120a of the liquid chamber 120 is less than 90°. This reduces the tensile stress applied when performing a liquid ejection operation, and extends the life of the liquid ejection head.

[0058] Next, an example of a manufacturing process for a liquid ejection head will be described with reference to Figures 9 and 10. Figures 9 and 10 are cross-sectional explanatory views illustrating the process.

[0059] As shown in Figure 9(a), a drive circuit 501 such as a CMOS circuit that drives the piezoelectric element 112 and an interlayer wiring layer 502 that connects the drive circuit 501 and the piezoelectric element 112 are formed on a silicon substrate 500 that becomes the liquid chamber forming member 102, as shown in Figure 9(b).

[0060] Next, as shown in FIG. 9( c ), an insulating layer 503 is formed to protect the drive circuit 501 and the interlayer wiring layer 502 , and then a vibration layer 504 that will become the thin layer member 111 is formed on the insulating layer 503 .

[0061] Then, as shown in FIG. 9(d), a contact portion 505A is formed on the interlayer wiring layer 502 to electrically connect the piezoelectric element 112 via the insulating layer 503 and the vibration layer 504, and a contact portion 505B is formed to connect to the drive circuit 501 via the insulating layer 503.

[0062] 9(e), an electrode film such as Pt is formed on the vibration layer 504, and photolithography and etching are performed to form the lower electrode 113. Also, an electrode pad 506 of the contact portion 505B that supplies power to the drive circuit 501 is formed. Then, after masking, a film of piezoelectric material is formed by a CVD or PVD process, and the mask is removed to form the piezoelectric film 114. Various materials such as PZT can be selected as the piezoelectric material.

[0063] Then, as shown in Figure 9(f), a mask for the upper electrode and wiring is applied to the piezoelectric film 114, and a film of electrode material is formed thereon, after which the mask is removed, and the upper electrode 115 is formed, while ensuring conductivity between the upper electrode 115 and one of the contact portions 505A.

[0064] Next, as shown in FIG. 10( a ), a protective layer 116 is formed on the entire surface of the front surface of the vibration layer 504 , including the surfaces of the piezoelectric elements 112 and the electrode pads 506 .

[0065] 10(b), photolithography and etching are performed from the rear surface side of the silicon substrate 500 to form the liquid chamber 120, thereby forming the liquid chamber forming member 102. At this time, the insulating layer 503 serves as an etch stop.

[0066] Next, as shown in FIG. 10( c ), photolithography is performed on the protective layer 116 to form an opening 116 a that will become part of the nozzle 110 , and a groove 116 b is formed in a portion that corresponds to the electrode pad 506 .

[0067] 10(d), the vibration layer 504 is etched using the protective film 116 as a mask to form an opening 504a that forms part of the nozzle 110. At this time, the electrode pad 506 is protected with a resist to prevent it from being etched.

[0068] Thereafter, the liquid ejection head is completed by assembling it together with components such as a separately manufactured common liquid chamber substrate.

[0069] Here, a specific example of the method for manufacturing the liquid ejection head according to the first embodiment of the present invention will be described.

[0070] 9 and 10, the protective layer 116 was a 0.5 μm thick BCB layer, the piezoelectric film 114 was a 2 μm thick AlN film, and the vibration layer 504 was a 2 μm thick Si layer. Then, a 1 μm thick SiO layer was formed between the vibration layer 504 and the lower electrode 113 as the insulating layer 503 with a stress adjustment function.

[0071] Because the SiO2 layer has compressive stress against the Si layer of the vibration layer 504, after the process is completed, the peripheral portion 130 of the nozzle 110 is warped in the direction opposite to the liquid ejection direction (toward the liquid chamber 120). Note that the warping is not shown explicitly in Figures 9 and 10 for the sake of simplicity.

[0072] This makes it possible to prevent the wiping member 201 from coming into contact with the nozzle 110 when performing a wiping operation, or to reduce the contact pressure of the wiping member 201. As a result, it is possible to reduce the repeated wiping load on the liquid-repellent film 117, and extend the life of the liquid-repellent film 117.

[0073] On the other hand, for nozzles 110 where a normal meniscus is not formed, in order to reliably remove dirt by wiping, a voltage (first voltage) is applied in the direction that contracts the piezoelectric element 112. As a result, as described above, the peripheral portion 130 of the nozzle 110 warps in the liquid ejection direction, which ensures reliable contact with the wiping member 201 and removal of dirt during wiping, and allows a normal meniscus to be formed with fewer wiping attempts.

[0074] Here, in the first embodiment, the layer structure is such that the peripheral portion 130 of the nozzle 110 warps in the direction opposite to the liquid ejection direction when no voltage is applied to the piezoelectric element 112. In contrast to this, by controlling the film thickness and residual stress of the layer structure in the nozzle 110 portion of the nozzle member 101, it is also possible to achieve a layer structure in which the peripheral portion 130 of the nozzle 110 warps in the liquid ejection direction when no voltage is applied to the piezoelectric element 112, as in the second embodiment.

[0075] Next, another example of a liquid ejection head according to Comparative Example 1, which is free from warping around the nozzles, will be described with reference to Fig. 11. Fig. 11 is a cross-sectional explanatory view illustrating this other example of the liquid ejection head.

[0076] This liquid ejection head uses an SOI substrate. In the manufacturing process of the liquid ejection head described above with reference to Figures 9 and 10, the parts corresponding to the silicon substrate 500, insulating layer 503, and vibration layer 504 are constructed from an SOI substrate. Therefore, the silicon substrate 500 is Si, the insulating layer 503 is SiO2, and the vibration layer 504 is Si.

[0077] In this way, by using an SOI substrate as the substrate that forms the liquid chamber 120 together with the drive circuit 501, the stray capacitance and leakage current generated in the drive circuit 501 can be reduced, thereby realizing faster printing processing and power saving by the liquid ejection head 100, while also improving the voltage resistance and reliability of the drive circuit.

[0078] Next, a specific example and a comparative example of the third embodiment will be described with reference to FIG.

[0079] As described above, when the ejection operation is repeated, stress is repeatedly applied to the joint between the liquid chamber side wall 120a and the thin layer member 111. When a voltage is applied to the piezoelectric element 112, the peripheral portion 130 of the nozzle 110 is displaced in a direction that increases the angle θ of the joint.

[0080] If this angle θ exceeds 90°, tensile stress is applied to the thin layer member 111 at the joint. Repeated application of tensile stress can cause cracks in the thin layer member 111, shortening its lifespan.

[0081] As Comparative Example 1, the liquid ejection head 100 of Comparative Example 1 as shown in FIG. 8 was fabricated using a 0.5 μm thick BCB layer as the protective layer 116, a 2 μm thick AlN piezoelectric element 112, and a 2 μm thick Si thin layer member 111.

[0082] When a square wave of ±150 V was applied to the liquid ejection head 100 of Comparative Example 1, a failure occurred due to a crack in the thin layer member 111 after a 1E9 pulse was input.

[0083] Therefore, in Example 1, the protective layer 116 was a 0.5 μm thick BCB layer, the piezoelectric element 112 was 2 μm thick AlN, and the thin layer member 111 was 2 μm thick Si.Furthermore, a 1 μm thick SiO2 layer was interposed between the thin layer member 111 and the lower electrode 113.

[0084] As a result, as explained in the third embodiment, the angle θ formed between the liquid chamber side wall 120a and the surface 101a of the thin member 111 on the liquid chamber side becomes less than 90°.

[0085] When a square wave of ±150 V was applied to the liquid ejection head 100 of Example 1, a failure occurred due to a crack in the thin layer member 111 after a 3E10 pulse was input. As a result, it can be seen that the head life is longer in Example 1 than in Comparative Example 1.

[0086] Next, an example of a liquid ejection device according to the present invention will be described with reference to Figures 12 and 13. Figure 12 is an explanatory plan view of the main parts of the device, and Figure 13 is an explanatory side view of the main parts of the device.

[0087] This liquid ejection device 1 is a serial type device, and a carriage 403 is moved back and forth in the main scanning direction by a main scanning movement mechanism 493. The main scanning movement mechanism 493 includes a guide member 401, a main scanning motor 405, a timing belt 408, etc. The guide member 401 is hung between left and right side plates 491A and 491B and movably holds the carriage 403. The main scanning motor 405 then moves the carriage 403 back and forth in the main scanning direction via a timing belt 408 hung between a drive pulley 406 and a driven pulley 407.

[0088] This carriage 403 is equipped with a liquid ejection unit 440 that integrates the liquid ejection head 100 according to the present invention and a head tank 441. The liquid ejection head 1 of the liquid ejection unit 440 ejects liquid of each color, for example, yellow (Y), cyan (C), magenta (M), and black (K). The liquid ejection head 1 has a nozzle row made up of multiple nozzles that is arranged in a sub-scanning direction perpendicular to the main scanning direction, and is mounted with the ejection direction facing downward.

[0089] A supply mechanism 494 for supplying the liquid stored outside the liquid ejection head 1 to the liquid ejection head 100 supplies the liquid stored in the liquid cartridge 450 to the head tank 441 .

[0090] The supply mechanism 494 is composed of a cartridge holder 451 which is a filling section to which the liquid cartridge 450 is attached, a tube 456, a liquid delivery unit 452 including a liquid delivery pump, etc. The liquid cartridge 450 is detachably attached to the cartridge holder 451. The liquid is delivered from the liquid cartridge 450 to the head tank 441 by the liquid delivery unit 452 via the tube 456.

[0091] This device is provided with a transport mechanism 495 for transporting paper 410. The transport mechanism 495 includes a transport belt 412, which is a transport means, and a sub-scanning motor 416 for driving the transport belt 412.

[0092] The conveyor belt 412 attracts the paper 410 and conveys it at a position facing the liquid ejection head 100. The conveyor belt 412 is an endless belt that is stretched between a conveyor roller 413 and a tension roller 414. The paper can be attracted by electrostatic attraction or air suction.

[0093] The conveyor belt 412 moves in a circular motion in the sub-scanning direction when the conveyor roller 413 is rotationally driven by a sub-scanning motor 416 via a timing belt 417 and a timing pulley 418 .

[0094] Furthermore, a maintenance and recovery mechanism 200 for performing maintenance and recovery of the liquid ejection head 1 is disposed on one side of the conveyor belt 412 on one side of the carriage 403 in the main scanning direction.

[0095] The maintenance and recovery mechanism 200 is made up of, for example, a cap member 421 that caps the ejection surface (nozzle surface) 118 of the liquid ejection head 100, a wiping member 201 that wipes the nozzle surface, and the like.

[0096] The main scanning movement mechanism 493, the supply mechanism 494, the maintenance and recovery mechanism 200, and the transport mechanism 495 are attached to a housing including side plates 491A and 491B and a back plate 491C.

[0097] In this device configured as described above, a sheet of paper 410 is fed onto and attracted to the conveyor belt 412, and the sheet of paper 410 is conveyed in the sub-scanning direction by the circular movement of the conveyor belt 412.

[0098] Therefore, by driving the liquid ejection head 100 in accordance with an image signal while moving the carriage 403 in the main scanning direction, liquid is ejected onto the stationary paper 410 to form an image.

[0099] Furthermore, the wiping member 201 of the maintenance and recovery mechanism 200 wipes and cleans the ejection surface 118 of the liquid ejection head 100. At this time, if necessary, the warping of the peripheral portion 130 of the nozzle 110 is controlled as described in the first to third embodiments. [Explanation of symbols]

[0100] 1. Liquid discharging device 100 Liquid ejection head 101 Nozzle member 102 Liquid chamber forming member 110 nozzle 111 Thin-Layered Members 111a aperture 112 Piezoelectric element 116 Protective layer 117 Liquid repellent film 118 Discharge surface 120 Liquid chamber 130 Periphery of the nozzle 200 Maintenance and Recovery Mechanism 201 Wiping member 300 Voltage application means 403 Carriage 440 Liquid Dispensing Unit 503 Insulation Layer 504 Vibration layer

Claims

[Claim 1] A nozzle member having a nozzle for discharging a liquid, The nozzle member is a deformable thin film member having an opening that forms the nozzle; an electromechanical transducer disposed around the opening, When no voltage is applied to the electromechanical transducer, the angle formed between the surface of the nozzle member facing the liquid chamber through which the nozzle communicates and the side wall surface of the liquid chamber is less than 90°. a liquid ejection head; a wiping member that wipes the ejection surface of the liquid ejection head; and means for applying a voltage to the electromechanical converter of the liquid ejection head so that, when the wiping member wipes the ejection surface, an angle formed between a surface of the nozzle member facing a liquid chamber through which the nozzle communicates and a side wall surface of the liquid chamber becomes larger than an angle when no voltage is applied to the electromechanical converter. A liquid ejection device comprising:

Images