JP2010201940A - Recording head and liquid ejecting apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid ejecting apparatus capable of obtaining a sufficient adhering pressure while securing the degree of evenness of an adhering surface with a case. <P>SOLUTION: The liquid ejecting apparatus includes a nozzle plate 17, a flow-channel forming part 30 in which a pressure generating chamber 2 and an ink reservoir 4 are formed and laminated on the nozzle plate 17, a vibrating plate 11 laminated on the flow-channel forming part 30, a piezoelectric element 6 that generates pressure in the pressure generating chamber 2 and a case member 23 onto which a laminate including the nozzle plate 17, the flow-channel forming part 30 and the vibrating plate 11 is pasted. In the region where the laminate is pasted to the case member 23, a damper-chamber forming plate 21 is included as a plate member having a thickness, resulting not only in securing the degree of evenness of the adhering surface with the case member 32, but also in enabling sufficient adhering pressure to be applied on adhering onto the case member 32, thus securing a sufficient adhering strength for adhesion to the recording head with the case member 32. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid ejecting apparatus that ejects liquid from a nozzle opening by vibration of a piezoelectric vibrator or the like.

  A liquid ejecting apparatus using a piezoelectric vibrator (in the following description, an example applied to an ink jet recording head, referred to as “recording head”) is generally provided with a piezoelectric element 6 attached to the upper surface as shown in FIG. An actuator unit 1 formed with a pressure generating chamber 2 corresponding to the piezoelectric element 6, and a flow path unit 5 formed with a nozzle opening 3 and an ink storage chamber 4 and adhered to the lower surface of the actuator unit 1. And pressure is generated in the pressure generating chamber 2 by the vibration of the piezoelectric element 6, and ink droplets are ejected from the nozzle openings 3.

  The actuator unit 1 includes a pressure generating chamber forming plate 10 in which a space for forming the pressure generating chamber 2 is formed, and a vibration plate 11 that is positioned on the upper surface of the pressure generating chamber forming plate 10 and closes the upper surface opening of the space. And a communication hole forming plate 14 located on the lower surface of the pressure generating chamber forming plate 10. The communication hole forming plate 14 is formed with a communication hole 12 for communicating the ink storage chamber 4 and the pressure generating chamber 2 and a nozzle communication path 8 for communicating the pressure generating chamber 2 and the nozzle opening 3.

  In the actuator unit 1, a common lower electrode 19 is formed on the upper surface of the diaphragm 11. A plate-like piezoelectric element 6 is formed on the upper surface of the lower electrode 19, and individual upper electrodes 20 are formed on the upper surface of the piezoelectric element 6. A drive signal is input to the piezoelectric element 6 through the lower electrode 19 and the upper electrode 20.

  On the other hand, the flow path unit 5 includes an ink storage chamber forming plate 16 in which a space for forming the ink storage chamber 4 is formed, and a nozzle that is formed in the lower surface of the ink storage chamber forming plate 16 with the nozzle opening 3 formed therein. The plate 17 and a supply port forming plate 18 located on the upper surface of the ink storage chamber forming plate 16 are configured. The ink storage chamber forming plate 16 is formed with a nozzle communication passage 8 that allows the pressure generation chamber 2 and the nozzle opening 3 to communicate with each other. In addition, the supply port forming plate 18 is provided with an ink supply port 9 for supplying ink from the ink storage chamber 4 to the pressure generation chamber 2 through the communication hole 12, and the pressure generation chamber 2 and the nozzle opening 3. Nozzle communication passage 8 is formed to communicate the.

  Further, the supply port forming plate 18 is formed with a space serving as a damper chamber 7 that relieves pressure fluctuation in the ink storage chamber 4 at a portion corresponding to the ink storage chamber 4. A damper plate 13 that closes the opening of the damper chamber 7 is sandwiched between the supply port forming plate 18 and the ink storage chamber forming plate 16.

  The actuator unit 1 is formed by laminating a diaphragm 11 made of ceramics, a pressure generating chamber forming plate 10 and a communication hole forming plate 14 and firing them integrally. On the other hand, in the flow path unit 5, a supply port forming plate 18, a damper plate 13, an ink storage chamber forming plate 16, and a nozzle plate 17 made of stainless steel are laminated via an adhesive layer 15. The actuator unit 1 and the flow path unit 5 are joined via an adhesive layer 15.

  However, in the recording head, the pressure generation chamber 2 is provided in the actuator unit 1, and the ink storage chamber 4 that supplies ink to the pressure generation chamber 2 and the nozzle opening 3 that discharges ink in the pressure generation chamber 2 include the flow path unit. 5 is provided. Moreover, the actuator unit 1 is made of ceramics, and the flow path unit 5 is made of stainless steel. For this reason, in order to make the pressure generating chamber 2, the ink storage chamber 4 and the nozzle opening 3 communicate with each other, it is necessary to laminate a plurality of parts with an adhesive, which complicates the structure and the manufacturing process and increases costs. It has become. Moreover, there exists a possibility that distortion | strain and peeling may generate | occur | produce by the difference in the thermal contraction rate and linear expansion coefficient of a bonding part. Furthermore, since the ink is in direct contact with the stainless steel and the adhesive, for example, an ink having an etching action on the stainless steel or an ink that elutes the adhesive cannot be used. There are limitations in the field of application.

  Therefore, recently, an ink jet recording head in which all members are formed of ceramics has been studied. As shown in FIG. 36, such a ceramic recording head includes not only the diaphragm 11, the pressure generating chamber forming plate 10, and the communication hole forming plate 14, but also the supply port forming plate 18, the damper plate 13, the ink storage chamber. It is conceivable that the forming plate 16 and the nozzle plate 17 are also formed of ceramics. When the ceramic recording head is manufactured, the vibration plate 11, the pressure generating chamber forming plate 10, the communication hole forming plate 14, the supply port forming plate 18, the damper plate 13, the ink storage chamber forming plate 16, and the nozzle plate 17 are used. It is considered that the respective plates can be joined without using the adhesive layer 15 by laminating and firing the green sheets of ceramic materials corresponding to the above.

  In general, in a recording head, a rectangular cylindrical case is attached to the upper surface of the vibration plate 11, and ink of an ink cartridge is supplied to an ink storage chamber through the case. However, since the ceramic recording head as described above is manufactured by firing a laminate of green sheets, a thin member such as the diaphragm 11 may be warped or damaged by an external force. It is considered easy. Therefore, if the part to be attached to the case is a thin plate, the flatness of the adhesive surface with the case is reduced or sufficient adhesion pressure cannot be obtained, and the recording head and the case are not sufficiently bonded. It is easy to become.

  The present invention has been made in view of such circumstances, and is a liquid jet capable of ensuring the flatness of the bonding surface with the case and obtaining sufficient bonding pressure and sufficiently securing the bonding strength between the recording head and the case. The purpose is to provide a device.

  In order to achieve the above object, a liquid ejecting apparatus of the present invention stores a ceramic nozzle plate having a nozzle opening, a pressure generating chamber communicating with the nozzle opening, and a liquid supplied to the pressure generating chamber. A ceramic flow path forming portion formed in a liquid storage chamber and stacked on the nozzle plate; a ceramic sealing plate stacked on the flow path forming portion and sealing an opening of the pressure generating chamber; and A pressure generating element that generates pressure in the pressure generating chamber; and a case member to which a laminated body including the nozzle plate, the flow path forming unit, and the sealing plate is attached, and is attached to the case member of the laminated body. The gist of the present invention is that a plate member having a thickness is included in the laminate.

  That is, the liquid ejecting apparatus of the present invention includes a plate member having a thickness in the laminated body in a region where the laminated body is attached to the case member. Since the plate member having the above thickness is unlikely to be warped and damaged by firing, the flatness of the adhesion surface with the case member is ensured and sufficient adhesion pressure is applied when adhering to the case member. it can. Accordingly, it is possible to sufficiently secure the bonding strength between the recording head and the case member.

  In the liquid ejecting apparatus of the present invention, the flow path forming portion includes a pressure generation chamber forming plate in which a pressure generation chamber is formed, a nozzle communication path that connects the pressure generation chamber and the nozzle opening, and a liquid storage chamber. A liquid storage chamber forming plate, a supply port for supplying liquid from the liquid storage chamber to the pressure generating chamber, and a supply port forming plate in which a nozzle communication path for communicating the nozzle opening and the pressure generating chamber is formed; When the path forming portion includes a damper chamber forming plate in which a damper chamber for absorbing pressure fluctuation in the liquid storage chamber is formed, and a damper plate sandwiched between the damper chamber and the liquid storage chamber, a laminated structure Thus, a ceramic recording head for firing a laminate of green sheets can be easily made.

  In the liquid ejecting apparatus according to the aspect of the invention, the damper chamber forming plate is provided with a nozzle communication passage for communicating the pressure generation chamber and the nozzle opening, and a communication hole for communicating the pressure generation chamber and the supply port. In the case of the damper chamber forming plate, the damper chamber forming plate, which requires a relatively large thickness, is a plate member having a thickness, so that the structure is not wasted and simple.

  In the liquid ejecting apparatus of the present invention, when the supply port forming plate also serves as the damper plate, the structure becomes simple because the supply port forming plate also serves as the damper plate.

  In the liquid ejecting apparatus of the present invention, when the damper chamber is formed on the pressure generating chamber forming plate, and the pressure generating chamber forming plate also serves as the damper chamber forming plate, the pressure generating chamber forming plate also serves as the damper plate. As a result, the structure is simplified, and the number of plates constituting the recording head can be reduced, which is advantageous in terms of cost and in terms of downsizing the recording head.

  In the liquid ejecting apparatus of the present invention, when the plate member having the above thickness is a pressure generating chamber forming plate, the pressure generating chamber forming plate having a relatively large thickness is used as a plate member having a thickness, thereby providing a structural Is simple and simple.

  In the liquid ejecting apparatus of the present invention, when the adhesive part substrate is laminated as a plate member having a thickness on the plate surface of the diaphragm, the adhesive part substrate ensures the flatness of the adhesive surface with the case member. In addition, sufficient adhesion pressure can be applied to the case member.

  In the liquid ejecting apparatus according to the aspect of the invention, the flow path forming unit includes a flow path forming plate in which the pressure generation chamber and the liquid storage chamber are formed, a nozzle communication path that connects the pressure generation chamber and the nozzle opening, and the liquid in the liquid storage chamber. In the case of including a supply port forming plate in which a supply port for supplying to the pressure generating chamber is formed, the structure is simple because the pressure generating chamber and the liquid storage chamber are formed on one flow path forming plate. In addition, the number of plates constituting the recording head can be reduced, which is advantageous in terms of cost and in terms of downsizing the recording head.

  In the liquid ejecting apparatus of the present invention, when a space is formed in the portion of the bonding portion substrate corresponding to the liquid storage chamber above the diaphragm, and the space absorbs pressure fluctuations in the liquid storage chamber, Since the above space functions as a damper chamber, there is no need to stack damper chamber forming plates and damper plates, the structure is simplified, and the number of plates constituting the recording head is reduced, which is advantageous in terms of cost. This is also advantageous in terms of downsizing the recording head.

  In the liquid ejecting apparatus according to the aspect of the invention, when the case member is a cylindrical body having a substantially cylindrical shape as a whole, and the end surface of the cylindrical body is attached to the peripheral edge of the laminated body, the pressure generating element is attached to the case. It can be housed in a member and protected.

  In the liquid ejecting apparatus according to the aspect of the invention, when there is no space portion in the region bonded to the case member of the pressure generation chamber forming plate, there is a space portion in the vicinity of the bonding portion of the region bonded to the case member. Therefore, it is possible to apply a sufficient adhesion pressure when adhering to the case.

  In the liquid ejecting apparatus of the present invention, when the thickness of the plate member having a thickness is 20 μm or more, the flatness of the bonding surface with the case member is sufficiently secured, and sufficient adhesion is achieved when bonding to the case member. Pressure can be applied.

1 is an exploded perspective view showing a basic structure of a liquid ejecting apparatus according to a first embodiment of the invention. It is AA sectional drawing of the said liquid injection apparatus. It is a top view which shows the nozzle plate which comprises the said liquid ejecting apparatus. It is a top view which shows the state by which the ink storage chamber formation board was laminated | stacked on the said nozzle plate. Furthermore, it is a top view which shows the state by which the supply port formation board was laminated | stacked. Furthermore, it is a top view which shows the state by which the damper chamber formation board was laminated | stacked. Furthermore, it is a top view which shows the state by which the pressure generation chamber formation board was laminated | stacked. Furthermore, it is a top view which shows the state by which the diaphragm was laminated | stacked. Furthermore, it is a top view which shows the state by which the lower electrode was laminated | stacked. Furthermore, it is a top view which shows the state by which the piezoelectric element was laminated | stacked. Furthermore, it is a top view which shows the state by which the upper electrode was laminated | stacked. Furthermore, it is a top view which shows the state by which the terminal was laminated | stacked. It is a perspective view of the laminated body of each said plate. It is AA sectional drawing of the liquid ejecting apparatus of the 2nd Embodiment of this invention. It is a top view which shows the nozzle plate which comprises the said recording head. It is a top view which shows the state by which the ink storage chamber formation board was laminated | stacked on the said nozzle plate. Furthermore, it is a top view which shows the state by which the supply port formation board was laminated | stacked. Furthermore, it is a top view which shows the state by which the pressure generation chamber formation board was laminated | stacked. Furthermore, it is a top view which shows the state by which the diaphragm was laminated | stacked. Furthermore, it is a top view which shows the state by which the lower electrode was laminated | stacked. Furthermore, it is a top view which shows the state by which the piezoelectric element was laminated | stacked. Furthermore, it is a top view which shows the state by which the upper electrode was laminated | stacked. Furthermore, it is a top view which shows the state by which the terminal was laminated | stacked. It is a perspective view of the laminated body of each said plate. It is AA sectional drawing of the liquid ejecting apparatus of the 3rd Embodiment of this invention. It is a top view which shows the nozzle plate which comprises the said recording head. It is a top view which shows the state by which the supply port formation board was laminated | stacked on the said nozzle plate. Furthermore, it is a top view which shows the state by which the flow-path formation board was laminated | stacked. Furthermore, it is a top view which shows the state by which the diaphragm and the adhesion part board | substrate were laminated | stacked. Furthermore, it is a top view which shows the state by which the lower electrode was laminated | stacked. Furthermore, it is a top view which shows the state by which the piezoelectric element was laminated | stacked. Furthermore, it is a top view which shows the state by which the upper electrode was laminated | stacked. Furthermore, it is a top view which shows the state by which the terminal was laminated | stacked. It is a perspective view of the laminated body of each said plate. It is sectional drawing which shows the liquid ejecting apparatus of a prior art example. It is sectional drawing which shows the liquid ejecting apparatus of another prior art example.

  Next, embodiments of the present invention will be described in detail.

  1 and 2 are views showing the basic structure of the liquid ejecting apparatus of the invention. In this embodiment, an example in which the liquid ejecting apparatus of the invention is applied to an ink jet recording head is shown. The recording head includes a nozzle plate 17 having a nozzle opening 3 formed therein, a flow path forming unit 30 in which a flow path of ink discharged from the nozzle opening 3 is formed and stacked on the nozzle plate 17. The vibration plate (sealing plate) 11 is provided on the flow path forming unit 30.

  The flow path forming unit 30 includes a pressure generation chamber forming plate 10 in which a pressure generation chamber 2 communicating with the nozzle opening 3 is formed, and an ink storage chamber 4 in which ink to be supplied to the pressure generation chamber 2 is stored. And a damper chamber forming plate 21 in which a damper chamber 7 for absorbing pressure fluctuation in the ink storage chamber 4 is formed.

  Further, the flow path forming unit 30 closes the upper opening of the ink storage chamber 4 and forms a supply port in which an ink supply port 9 for supplying ink stored in the ink storage chamber 4 to the pressure generation chamber 2 is formed. A plate 18 is provided. The supply port forming plate 18 is sandwiched between the damper chamber 7 and the ink storage chamber 4 so as to close the lower opening of the damper chamber 7 and is elastically deformed by the pressure variation in the ink storage chamber 4 to thereby reduce the pressure variation. 7 also functions as a damper plate to escape.

  The flow path forming unit 30 is configured by laminating the ink storage chamber forming plate 16, the supply port forming plate 18, the damper chamber forming plate 21, and the pressure generating chamber forming plate 10 in this order from the nozzle plate 17 side. . Here, each of the ink storage chamber forming plate 16, the supply port forming plate 18, and the damper chamber forming plate 21 is provided with a nozzle communication passage 8 that allows the nozzle opening 3 and the pressure generating chamber 2 to communicate with each other. The damper chamber forming plate 21 is provided with a communication hole 12 that allows the ink supply port 9 and the pressure generating chamber 2 to communicate with each other.

  On the other hand, a comb-like lower electrode 19 is formed on the upper surface of the diaphragm 11. Each comb tooth portion 19 </ b> A of the lower electrode 19 is formed in a portion covering the upper portion of the pressure generating chamber 2. In addition, a plate-like piezoelectric element 6 is formed on the upper surface of each comb tooth portion 19A of the lower electrode 19, and an individual upper electrode 20 is formed on the upper surface of the piezoelectric element 6. A drive signal is applied to each piezoelectric element 6 through the upper electrode 20 and the lower electrode 19.

  A flow path forming unit 30 is stacked on the nozzle plate 17, and the diaphragm 11 on which the piezoelectric element 6, the lower electrode 19, and the upper electrode 20 are formed is stacked on the flow path forming unit 30. Furthermore, the end surface of the square cylindrical case member 23 is attached to the peripheral edge of the upper surface of the laminated body of the nozzle plate 17, the flow path forming unit 30, and the vibration plate 11. In the figure, 26 is an ink supply port for supplying ink from an ink cartridge (not shown) or the like to the ink storage chamber 4, and 39 is an ink supply path communicating with the ink supply port 26.

  In the recording head, when a drive signal is applied to the piezoelectric element 6, the piezoelectric element 6 contracts in the lateral direction. At this time, the lower surface side of the piezoelectric element 6 fixed to the vibration plate 11 does not contract, but only the upper surface side contracts. Therefore, the piezoelectric element 6 and the vibration plate 11 bend downward and compress the pressure generating chamber 2. Then, as the pressure in the pressure generation chamber 2 rises, the ink in the pressure generation chamber 2 is ejected as ink droplets from the nozzle openings 3, and dots are formed on the recording paper or the like to perform printing. Next, when the piezoelectric element 6 is discharged and returns to the original state, the pressure generation chamber 2 is depressurized, and new ink is supplied from the ink storage chamber 4 to the pressure generation chamber 2 through the ink supply port 9.

  Here, the top view of each plate is shown in FIGS. 3 shows the nozzle plate 17, FIG. 4 shows a state in which the ink storage chamber forming plate 16 is laminated on the nozzle plate 17, FIG. 5 shows a state in which a supply port forming plate 18 is further laminated, and FIG. 7 is a state in which the damper chamber forming plate 21 is further laminated, FIG. 7 is a state in which the pressure generating chamber forming plate 10 is further laminated, FIG. 8 is a state in which the vibration plate 11 is further laminated, and FIG. 10 shows a state in which the electrode 19 is laminated, FIG. 10 shows a state in which the piezoelectric element 6 is further laminated (the lower electrode 19 is not shown), and FIG. 11 shows a state in which the upper electrode 20 is further laminated (the lower electrode 19 and the piezoelectric element). FIG. 12 shows a state in which the terminals 31 are further laminated (the lower electrode 19, the piezoelectric element 6 and the upper electrode 20 are not shown). FIG. 13 is a perspective view of the laminate of the plates. In each figure, 22 is a positioning hole for positioning when laminating each plate. In FIG. 13, the hatched portion 32 indicates an area where the case member 23 is attached.

  In this recording head, the pressure generating chambers 2 are arranged in a row. The tips of the comb teeth 19 </ b> A of the lower electrode 19 are disposed on the terminal raising member 27, and the tips of the comb teeth 19 </ b> A excluding both ends of the row of the pressure generating chamber 2 are insulated by the insulating portion 29. Has been. The tips of the comb teeth 19 </ b> A located at both ends of the row of the pressure generating chambers 2 are used as a common terminal 28 when inputting a drive signal to the lower electrode 19. Therefore, the pressure generating chambers 2A at both ends of the row corresponding to each common terminal 28 are not driven and do not discharge ink droplets.

  No nozzle communication passages 8 are formed in portions corresponding to the pressure generation chambers 2A at both ends of each of the damper chamber forming plate 21, the supply port forming plate 18, and the ink storage chamber forming plate 16, respectively. Further, the ink supply port 9 and the communication hole 12 are not formed in the portion corresponding to the pressure generation chamber 2A at both ends of the row of the supply port forming plate 18, and the pressure generation chambers at both ends of the row of the nozzle plate 17 are formed. No nozzle opening 3 is formed in a portion corresponding to 2A.

  As a result, the pressure generation chambers 2A at both ends of the row do not communicate with the nozzle openings 3 and the ink storage chambers 4, and are independent spaces other than the ink flow paths. On the other hand, the damper chamber 7 is also an independent space other than the flow path that does not communicate with the ink flow path.

  Here, in the recording head, the nozzle plate 17, the flow path forming unit 30 (the ink storage chamber forming plate 16, the supply port forming plate 18, the damper chamber forming plate 21, the pressure generating chamber forming plate 10), and the vibration plate 11 are all included. It is formed from ceramics.

  The recording head as described above is produced, for example, as follows. That is, first, a green sheet of ceramic is prepared, and the green sheet is punched out, and the nozzle plate 17, the ink storage chamber forming plate 16, the supply port forming plate 18, the damper chamber forming plate 21, the pressure generating chamber forming plate 10, and the vibration. Plates corresponding to the plates 11 are formed. At this time, spaces corresponding to the ink storage chamber 4, the damper chamber 7, the ink supply port 9, the pressure generation chamber 2, the nozzle communication path 8, and the communication hole 12 are formed by punching or the like.

  Then, green sheets corresponding to the nozzle plate 17, the ink storage chamber forming plate 16, the supply port forming plate 18, the damper chamber forming plate 21, the pressure generating chamber forming plate 10, and the vibration plate 11 are laminated in a predetermined order and then fired. By doing so, it is possible to obtain a recording head integrally formed of ceramics without using an adhesive.

  Here, in the recording head, the pressure generating chamber forming plate 10 is laminated as a plate member having a thickness on the laminated body of each plate in the hatched portion 32 where the case member 23 is adhered. In other words, by positioning the damper chamber forming plate 21 between the pressure generating chamber forming plate 10 and the ink storage chamber forming plate 16, the pressure generating chamber forming plate 10 functions as a plate member having a thickness. By doing in this way, since the damper chamber forming plate 21 having the above-mentioned thickness is unlikely to be warped or damaged by firing, the flatness of the adhesive surface with the case member 23 is ensured, and the case member 23 and Adhesive pressure can be applied sufficiently when bonding.

  The thickness dimension of the plate member having the above thickness is preferably set to at least 20 μm or more. The thickness dimension is more preferably 50 μm or more, and most preferably 80 μm or more. If the thickness dimension is less than 20 μm, warping due to firing is likely to occur and damage is likely to occur, so that the flatness of the bonding surface with the case member 23 cannot be secured, and sufficient bonding pressure is applied when bonding to the case member 23. It is because it becomes impossible.

  Further, as a stacking order of the ink storage chamber forming plate 16, the supply port forming plate 18, and the damper chamber forming plate 21 when manufacturing the recording head, first, the damper chamber forming plate 21 is stacked on the supply port forming plate 18. Then, it is preferable that pressure is applied in the up and down direction, and then the ink storage chamber forming plate 16 is laminated on the lower surface of the supply port forming plate 18 and pressure is applied in the up and down direction to perform pressure bonding. By doing so, even if the damper chamber 7 is smaller than the ink storage chamber 4 as in this example, the supply port forming plate 18 and the damper chamber forming plate 21 are brought into close contact with each other in advance. There is no poor adhesion between the supply port forming plate 18 and the damper chamber forming plate 21 in the corresponding space.

  Further, in the recording head, the pressure generating chambers 2A and the damper chambers 7 at both ends of the row are independent spaces other than the flow channel that does not communicate with the ink flow channel, so that these independent spaces exist in a closed state. In the step of laminating the green sheets, the air in the independent space does not escape sufficiently. In the step of firing the laminate, the air confined in the independent space expands and distortion occurs in the joint portion of the plate around the independent space, so that the plates are not sufficiently joined or the joint portion is easily peeled off. .

  Therefore, in the recording head, the plate stacked above the pressure generating chamber 10 has a second external communication hole 25 that allows the damper chamber 7, which is an independent space, to communicate with the outside at a location corresponding to the damper chamber 7. The damper chamber 7 is opened to the atmosphere opposite to the nozzle plate 17. Further, a first external communication hole 24 that allows the pressure generating chamber 2A, which is an independent space, to communicate with the outside is formed in a plate stacked above the pressure generating chamber forming plate 10, and the damper chamber forming plate 21 has the first external communication hole. A long hole 38 for communicating the communication hole 24 with the pressure generating chamber 2A, which is an independent space, is formed, and the pressure generating chamber 2A is opened to the atmosphere opposite to the nozzle plate 17. Here, since the upper electrode 20, the lower electrode 19, and the piezoelectric element 6 are laminated on the upper side of the pressure generation chamber 2 </ b> A, it is difficult to directly communicate with the outside like the second external communication hole 25. Therefore, by forming the long hole 38, the communication path is extended to a place where the upper electrode 20, the lower electrode 19 and the piezoelectric element 6 do not exist.

  By doing so, even if there is an independent space that is not an ink flow path, such as the pressure generation chamber 2A or the damper chamber 7 at both ends of the row, the independent space is provided with the first and second external communication holes 24, 25, since the air in the independent space escapes sufficiently at the stage of stacking the green sheets, and the air trapped in the independent space expands at the stage of firing the laminate, Air is discharged from the second external communication holes 24 and 25. Accordingly, there is almost no occurrence of distortion at the joint portion of the plate around the independent space or insufficient joining between the plates.

  Further, since the first and second external communication holes 24 and 25 are opened on the side opposite to the nozzle plate 17, the ink enters the damper chamber 7 and the like from the first and second external communication holes 24 and 25. There will be no problems such as impeding the damper effect. In addition, the pressure generation chambers 2A located at both ends of the row of the pressure generation chambers 2 arranged in a row are not communicated with the nozzle openings 3 so that ink droplets are not ejected, thereby generating pressure for ejecting ink droplets. Since the chamber 2 is always sandwiched between the other pressure generating chambers 2 and 2A, the pressure generating chamber 2 for ejecting ink droplets can be stably obtained in production, and the ejection characteristics are also stabilized.

  The ceramic material constituting the recording head is not particularly limited, and various materials can be used. For example, various carbides such as silicon carbide, titanium carbide, chromium carbide, niobium carbide, vanadium carbide, zirconium carbide, molybdenum carbide, boron carbide, zirconium oxide (zirconia), aluminum oxide, magnesium oxide, silicon oxide, titanium oxide, beryllium oxide Various oxides such as aluminum nitride, various nitrides such as silicon nitride, beryllium nitride and boron nitride, various borides such as zirconium boride, chromium boride and titanium boride, and composite compounds such as sialon I can give you. These may be used alone or in combination. Among these, zirconia is excellent in mechanical strength and toughness and excellent in corrosion resistance, and is suitable as a material constituting the liquid ejecting apparatus.

  In the recording head described above, warpage due to firing hardly occurs and damage does not easily occur, so that the flatness of the adhesion surface with the case member 23 is ensured and sufficient adhesion pressure can be applied when adhering to the case member 23. Therefore, sufficient bonding strength between the recording head and the case member 23 can be ensured. Moreover, since the pressure generating chamber forming plate 10 that requires a relatively large thickness is a plate member having a thickness, the structure is not wasteful and simple, and the supply port forming plate 18 functions as a damper plate. Becomes even simpler.

  In the recording head, since the flow path forming portion 30, the vibration plate 11, and the nozzle plate 17 are each formed of ceramics, all of the flow paths that come into contact with the ink are formed of ceramics. Ink properties are dramatically improved. Therefore, the type of ink to be used is not limited, and for example, an ink having an etching action on stainless steel or an ink that elutes an adhesive can be used, and there are almost no restrictions on the characteristics of the ink to be used. Further, since the chemical stability of the flow path is improved and elution of organic substances is eliminated, for example, it can be used in the food field, the medical field, and the like, and there are almost no restrictions in the field of application.

  Further, in the recording head, since the laminated body of the flow path forming portion 30, the vibration plate 11, and the nozzle plate 17 is integrally formed without an adhesive layer, a bonding operation becomes unnecessary. There is no risk of distortion or peeling due to differences in thermal contraction rate or linear expansion coefficient. Furthermore, since it has a laminated structure, it is suitable for production from ceramic green sheets.

FIG. 14 shows a liquid ejecting apparatus according to the second embodiment of the present invention.
Here, the top view of each plate is shown in FIGS. 15 shows the nozzle plate 17, FIG. 16 shows a state in which the ink storage chamber forming plate 16 is laminated on the nozzle plate 17, FIG. 17 shows a state in which a supply port forming plate 18 is further laminated, and FIG. Further, FIG. 19 shows a state where the pressure generating chamber forming plate 10 is further laminated, FIG. 19 shows a state where the diaphragm 11 is further laminated, FIG. 20 shows a state where the lower electrode 19 is further laminated, and FIG. Are stacked (lower electrode 19 is not shown), FIG. 22 is a state where upper electrode 20 is further stacked (lower electrode 19 and piezoelectric element 6 are not shown), FIG. It is in a laminated state (lower electrode 19, piezoelectric element 6 and upper electrode 20 are not shown). FIG. 24 is a perspective view of the laminate of the plates. In FIG. 24, a hatched portion 32 indicates a region where the case member 23 is attached.

  In this recording head, a damper chamber forming plate 21 is not provided in the flow path forming portion 30, and a damper chamber 7 is formed in a portion corresponding to the ink storage chamber 4 of the pressure generating chamber forming plate 10. Further, the damper chamber 7 does not exist in a portion corresponding to the hatched portion 32 which is an area to be attached to the case member 23 of the pressure generating chamber forming plate 10. Further, a thinned portion 33 is formed in the ink storage chamber forming plate 16, and a third external communication hole 34 that communicates the inside of the thinned portion 33 with the outside is formed on the plate stacked above the supply port forming plate 18. It has been drilled. Other than that, it is the same as that of the said 1st Embodiment, and attaches | subjects the same code | symbol to the same part.

  This recording head has a structure in which there is no space in the vicinity of the region where the pressure generating chamber forming plate 10 is attached to the case member 23, and can sufficiently apply an adhesive pressure when adhering to the case member 23. Further, since the damper chamber 7 is formed in the pressure generating chamber forming plate 10 and this pressure generating chamber forming plate 10 also serves as the damper chamber forming plate, the structure becomes simple and the number of plates constituting the recording head is small. This is advantageous in terms of cost and in terms of downsizing the recording head. In addition, since the thinned portion 33 is provided in the ink storage chamber forming plate 16, the thickness of the ink storage chamber forming plate 16 becomes almost uniform throughout, and warpage during firing can be prevented. Other than that, there exists an effect similar to the said 1st Embodiment.

FIG. 25 illustrates a liquid ejecting apparatus according to a third embodiment of the invention.
Here, FIGS. 26 to 33 show plan views of the respective plates. 26 shows the nozzle plate 17, FIG. 27 shows a state in which the supply port forming plate 18 is laminated on the nozzle plate 17, FIG. 28 shows a state in which a flow path forming plate 35 is further laminated, and FIG. Further, FIG. 30 shows a state where a lower electrode 19 is further laminated, and FIG. 31 shows a state where a piezoelectric element 6 is further laminated (the lower electrode 19 is not shown). 32 shows a state in which the upper electrode 20 is further laminated (the lower electrode 19 and the piezoelectric element 6 are not shown), and FIG. 33 shows a state in which the terminal 31 is further laminated (the lower electrode 19 and the piezoelectric element). 6 and the upper electrode 20 are not shown). FIG. 34 is a perspective view of the laminate of the plates. In FIG. 34, a hatched portion 32 indicates an area where the case member 23 is attached.

  In this recording head, the flow path forming unit 30 includes a flow path forming plate 35 in which the pressure generation chamber 2 and the ink storage chamber 4 are formed, a nozzle communication path 8 that connects the pressure generation chamber 2 and the nozzle opening 3, and an ink storage. A supply port forming plate 18 in which a supply port 9 for supplying ink in the chamber 4 to the pressure generating chamber 2 is formed is laminated. In addition, an adhesive portion substrate 36 is laminated on the plate surface of the diaphragm 11 as a plate member having a thickness. This adhesion part board | substrate 36 is exhibiting the frame shape corresponding to the area | region where the case member 23 is affixed. Further, a space 37 is formed in a portion corresponding to the ink storage chamber 4 above the vibration plate 11, and the vibration plate 11 is elastically deformed by pressure fluctuation in the ink storage chamber 4 so that the space 37 absorbs the pressure fluctuation. It has become. Other than that, it is the same as that of the said 1st Embodiment, and attaches | subjects the same code | symbol to the same part.

  In the recording head, since the bonding portion substrate 36 is laminated as a member having a thickness, the bonding portion substrate 36 ensures the flatness of the bonding surface with the case member 23 and adheres to the case member 23. Sufficient adhesive pressure can be applied. In addition, since the pressure generating chamber 2 and the ink storage chamber 4 are formed on one flow path forming plate 35 and the space 37 above the vibration plate 11 functions as a damper chamber, a damper chamber forming plate and a damper are formed. There is no need to stack plates, the structure is simple, the number of plates constituting the recording head can be reduced, which is advantageous in terms of cost and in terms of miniaturization of the recording head. Furthermore, since the diaphragm 11 functions as a damper plate, the damper effect is excellent. Other than that, there exists an effect similar to the said 1st Embodiment.

  In each of the above-described embodiments, the present invention is applied to an ink jet recording head using a flexural vibration mode piezoelectric vibrator. However, the present invention is not limited to this, and longitudinal vibration mode piezoelectric vibration. The present invention can be applied to an ink jet recording head using a child, and can also be applied to a recording head using a heating element that heats ink in a flow path as a pressure generating element.

  Further, in each of the above embodiments, an example in which the liquid ejecting apparatus of the present invention is applied to an ink jet recording head has been described. However, the present invention is not limited thereto. For example, the liquid to be discharged is a fuel such as gasoline, It can also be used as a fuel injection device for an internal combustion engine. Furthermore, the present invention can also be applied to the formation of an organic light emitting layer for a display body in which an organic light emitting layer is formed on a transparent electrode formed in a matrix on a transparent substrate. Thus, in the liquid ejecting apparatus of the present invention, various liquids can be applied as the liquid to be ejected, and can be applied to various industrial fields.

(The invention's effect)
As described above, according to the liquid ejecting apparatus of the present invention, since the plate member having a thickness is included in the laminate in the region to be attached to the case member of the laminate, the plate having the thickness is included. Since the member is not easily warped by firing and is not easily damaged, the flatness of the bonding surface with the case member is ensured, and sufficient bonding pressure can be applied when bonding the case member. Therefore, it is possible to sufficiently secure the bonding strength between the recording head and the case.

  2 pressure generation chamber, 4 ink storage chamber, 6 piezoelectric element, 11 vibration plate, 17 nozzle plate, 21 damper chamber forming plate, 23 case member, 30 flow path forming portion.

Claims (13)

  A ceramic nozzle plate having a nozzle opening formed therein, a pressure generation chamber communicating with the nozzle opening, and a liquid storage chamber for storing a liquid to be supplied to the pressure generation chamber, and ceramics laminated on the nozzle plate A flow path forming section made of ceramic, a ceramic sealing plate laminated on the flow path forming section to seal the opening of the pressure generating chamber, a pressure generating element for generating pressure in the pressure generating chamber, and the nozzle A plate member including a plate, a flow path forming unit, and a laminated body including a sealing plate, and the laminated body includes a plate member having a thickness in the region to be adhered to the case member. A liquid ejecting apparatus.   The flow path forming portion includes a pressure generation chamber forming plate in which a pressure generation chamber is formed, a nozzle communication path that connects the pressure generation chamber and a nozzle opening, and a liquid storage chamber forming plate in which a liquid storage chamber is formed; The liquid ejecting apparatus according to claim 1, further comprising: a supply port that supplies liquid from the liquid storage chamber to the pressure generation chamber, and a supply port forming plate in which a nozzle communication path that connects the nozzle opening and the pressure generation chamber is formed.   The said flow path formation part contains the damper chamber formation board in which the damper chamber which absorbs the pressure fluctuation in a liquid storage chamber was formed, and the damper board pinched | interposed between the said damper chamber and a liquid storage chamber. Liquid ejector.   The damper chamber forming plate is formed with a nozzle communication passage for communicating the pressure generating chamber and the nozzle opening, and a communication hole for communicating the pressure generating chamber and the supply port, and a plate member having a thickness is the damper chamber forming plate. Item 4. The liquid ejecting apparatus according to Item 3.   The liquid ejecting apparatus according to claim 3, wherein the supply port forming plate also serves as a damper plate.   The liquid ejecting apparatus according to claim 3, wherein a damper chamber is formed on the pressure generating chamber forming plate, and the pressure generating chamber forming plate also serves as the damper chamber forming plate.   The liquid ejecting apparatus according to claim 2, wherein the plate member having the thickness is a pressure generation chamber forming plate.   The liquid ejecting apparatus according to claim 1, wherein an adhesive portion substrate is laminated as a plate member having a thickness on a plate surface of the diaphragm.   The flow path forming unit includes a flow path forming plate in which the pressure generation chamber and the liquid storage chamber are formed, a nozzle communication path for communicating the pressure generation chamber and the nozzle opening, and a supply port for supplying the liquid in the liquid storage chamber to the pressure generation chamber The liquid ejecting apparatus according to claim 8, further comprising a supply port forming plate on which is formed.   The liquid ejecting apparatus according to claim 9, wherein a space is formed in a portion of the bonding portion substrate corresponding to the liquid storage chamber above the vibration plate, and the space absorbs pressure fluctuation in the liquid storage chamber.   The liquid ejecting apparatus according to any one of claims 1 to 10, wherein the case member is a cylindrical body having a substantially cylindrical shape as a whole, and an end surface of the cylindrical body is attached to a peripheral edge portion of the laminated body.   The liquid ejecting apparatus according to any one of claims 1 to 3, wherein a space portion does not exist in an area where the pressure generating chamber forming plate is attached to the case member.   The liquid ejecting apparatus according to claim 1, wherein the plate member having a thickness has a thickness of 20 μm or more.

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