JP2007234765A - Manufacturing method for piezoelectric element unit, and fixture - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for a piezoelectric element unit capable of excellently cutting and dividing a plurality of piezoelectric-element forming members pectinately at a stretch, and to provide a fixture preferably used for the manufacturing method. <P>SOLUTION: A plurality of the piezoelectric-element forming members 13 are made to run parallel and fixed on a table 105 by the fixtures 200, and a wire 104 wrapped to a pair of rollers 101 and 102 is brought into contact and made to travel to a plurality of these piezoelectric-element forming members 13. Consequently, when each piezoelectric-element forming member 13 is cut and divided pectinately and the row of piezoelectric elements is formed, a height h1 to the table 105 of the piezoelectric-element forming members 13 arranged at a central section between a pair of the rollers 101 and 102 is made higher than that to the table 105 of the piezoelectric-element forming members 13 arranged on both-end section sides. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a piezoelectric element unit including a piezoelectric element that is displaced by applying a voltage to a piezoelectric material layer, and a fixing jig used therefor.

  As a device using a piezoelectric element, a part of a pressure generating chamber communicating with a nozzle opening is configured by a diaphragm, and the diaphragm is deformed by a piezoelectric element to pressurize a liquid, for example, ink in the pressure generating chamber. A liquid ejecting head that discharges liquid droplets from a nozzle opening, and the like, include one using a longitudinal vibration mode piezoelectric element (piezoelectric vibrator) that expands and contracts in the axial direction. As a piezoelectric element in such a longitudinal vibration mode, a piezoelectric element forming member (piezoelectric vibrating plate) in which a common internal electrode and individual internal electrodes are stacked with a piezoelectric material sandwiched therebetween is fixed to a fixed substrate, and the piezoelectric element forming member is fixed to a wire saw. Some of them are formed by cutting into comb teeth by a device. That is, as a piezoelectric element in the longitudinal vibration mode, one configured as a piezoelectric element (piezoelectric vibrator) unit in which a plurality of piezoelectric elements are integrally formed is known (for example, see Patent Document 1).

  As described above, the piezoelectric element unit is formed by cutting the piezoelectric element forming member into comb teeth by the wire saw device. In general, for example, a plurality of piezoelectric element units are fixed in parallel, and a plurality of piezoelectric element units (piezoelectric element forming members) are processed simultaneously. However, when a plurality of piezoelectric element units are processed at the same time as described above, there is a problem that the wire is bent by a load due to contact with the piezoelectric element forming member, and the slit depth varies in each piezoelectric element unit. . Such variation in slit depth can be eliminated by performing so-called stop-cutting while the movement of the piezoelectric element unit is stopped, but the width of each piezoelectric element varies. There is a fear. That is, by performing stop cutting, in the slit formed at a predetermined depth in the initial stage, substantially the same place is processed for a long time, and the width of the slit partially expands, and the width of the piezoelectric element There is a risk that variations will occur.

  In order to solve such a problem, it is conceivable to increase the tension of the wire, but it is not preferable because the wire is easily cut. Although it is conceivable to reduce the processing speed, it is not preferable because the wire is distorted and the width of the piezoelectric element tends to vary. Although it is conceivable to shorten the interval between the rollers around which the wire is wound, it is necessary to change the apparatus itself, and the number of piezoelectric element units that can be manufactured at one time is reduced, resulting in an increase in cost. Therefore, it is not preferable.

JP 11-129474 A

  In view of such circumstances, the present invention provides a method for manufacturing a piezoelectric element unit that can satisfactorily cut a plurality of piezoelectric element forming members at once into a comb-tooth shape, and a fixing jig suitably used for the method. Let it be an issue.

According to a first aspect of the present invention for solving the above-mentioned problems, there is provided a piezoelectric element unit comprising a row of piezoelectric elements in which a piezoelectric element forming member having an individual electrode layer and an individual electrode layer and a piezoelectric material layer is cut into a comb shape. In the manufacturing method, a plurality of piezoelectric element forming members are arranged in parallel, fixed on a table with a fixing jig, and each of the plurality of piezoelectric element forming members is moved in contact with a wire wound around a pair of rollers. Piezoelectric element forming members are cut into comb-like shapes to form rows of the piezoelectric elements. At this time, the height of the piezoelectric element forming member arranged at the center between the pair of rollers with respect to the table is set at both end portions. The piezoelectric element unit manufacturing method is characterized in that the height of the piezoelectric element forming member disposed on the side is higher than the height of the table.
In the first aspect, the depth of each slit formed when the piezoelectric element forming member is cut into a comb shape can be made uniform. That is, it is possible to form a row of piezoelectric elements without stopping. Therefore, the displacement characteristics of each piezoelectric element can be improved and the displacement characteristics can be made uniform.

According to a second aspect of the present invention, each of the piezoelectric element forming members arranged in parallel is based on the amount of bending of the wire at a position corresponding to each piezoelectric element forming member when the piezoelectric element forming member is cut into a comb shape. The method of manufacturing a piezoelectric element unit according to the first aspect is characterized in that at least the height of each of the piezoelectric element units is corrected.
In the second aspect, the depth of each slit formed when the piezoelectric element forming member is cut into a comb-teeth shape can be made more uniform.

According to a third aspect of the present invention, in the piezoelectric element unit according to the second aspect, the height of the piezoelectric element forming member with respect to the table increases as the amount of bending of the wire increases. Is in the way.
In the third aspect, the depth of each slit formed when the piezoelectric element forming member is cut into a comb-teeth shape can be made more uniform.

According to a fourth aspect of the present invention, the piezoelectric element forming member is cut into a comb-like shape in a state where each piezoelectric element forming member is inclined with respect to the table, and at that time, the wire of each piezoelectric element forming member and the wire The piezoelectric element unit manufacturing method according to any one of the first to third aspects is characterized in that the angle of each piezoelectric element forming member is further corrected so that the crossing angles of the piezoelectric elements are the same.
In the fourth aspect, the depth of each slit formed when the piezoelectric element forming member is cut into a comb-teeth shape can be made more uniform.

The fifth aspect of the present invention is used for the manufacture of a piezoelectric element unit comprising a piezoelectric element row in which a piezoelectric element forming member having an individual electrode layer and an individual electrode layer and a piezoelectric material layer is cut into a comb shape. A plurality of the piezoelectric element forming members are moved in contact with a wire wound around a pair of rollers, and each piezoelectric element forming member is cut into a comb-like shape to form a row of the piezoelectric elements. A fixing jig for fixing a piezoelectric element forming member on a table, having a plurality of fixing portions on which the piezoelectric element forming members are respectively arranged, and the height of each fixing portion with respect to the table being independent from each other The fixing jig is characterized by being adjustable.
In the fifth aspect, the height of each piezoelectric element forming member can be easily adjusted by adjusting the height of the fixed portion.

According to a sixth aspect of the present invention, there is provided a fixing jig according to the fifth aspect, characterized in that a plurality of fixing members having the fixing portion are connected.
In the sixth aspect, the height of the fixing portion can be easily adjusted.

Hereinafter, the present invention will be described in detail based on embodiments.
FIG. 1 is a perspective view showing an example of a piezoelectric element unit manufactured by the manufacturing method of the present invention, and FIG. 2 is a plan view and a cross-sectional view of FIG.

  As shown in FIGS. 1 and 2, the piezoelectric element unit 10 includes a piezoelectric element forming member 13 having a row 12 in which a plurality of piezoelectric elements 11 are arranged in the width direction, and a base end portion of the piezoelectric element forming member 13. And a fixed substrate 14 that fixes the tip portion as a free end, and is mounted on a liquid jet head such as an ink jet recording head.

  The piezoelectric element forming member 13 includes an individual electrode layer, a common electrode layer, and a piezoelectric material layer. For example, in the present embodiment, the piezoelectric element forming member 13 constitutes the piezoelectric material layer 15 and an internal electrode constituting two poles of the piezoelectric element 11, that is, an individual electrode that is electrically independent from the adjacent piezoelectric element 11. The internal electrodes 16 and the internal electrodes 17 constituting a common electrode electrically common to the adjacent piezoelectric elements 11 are alternately stacked and stacked. Of course, the piezoelectric element forming member 13 is not limited to the configuration of the present embodiment, and may be any member having an individual electrode layer, a common electrode layer, and a piezoelectric material layer. As will be described in detail later, the piezoelectric element forming member 13 is formed with a plurality of slits 18 by a wire saw device, that is, by cutting into a comb-like shape, thereby forming a row 12 of piezoelectric elements 11. . Further, on both sides of the row 12 of the piezoelectric elements 11, similarly to the piezoelectric elements 11, the piezoelectric element forming members 13 are formed by cutting them into comb teeth, and positioning portions 19 having a wider width than the respective piezoelectric elements 11 are provided. It has been. The positioning portion 19 is provided to position the piezoelectric element unit 10 with high accuracy when the piezoelectric element unit 10 is incorporated into an ink jet recording head or the like.

  Here, the internal electrode 16 that is an individual electrode of each piezoelectric element 11 is basically provided over substantially the entire surface of the piezoelectric element forming member 13, but the tip is in a region facing the vicinity of the end face of the fixed substrate 14. The side and the base end side are provided separately. On the other hand, the internal electrode 17 serving as a common electrode is basically provided over substantially the entire surface of the piezoelectric element forming member 13, but is separated in the same manner as the internal electrode 16 in the vicinity of the tip of the piezoelectric element 11. That is, the region bonded to the fixed substrate 14 of the piezoelectric element 11 is an inactive region that does not contribute to vibration, and when a voltage is applied between the internal electrodes 16 and 17 of both electrodes constituting the piezoelectric element 11, the fixed substrate Only the tip end side that is not joined to 14 vibrates.

  An external electrode layer 20 connected to the internal electrodes 16 and 17 is formed on the outer surface of the piezoelectric element forming member 13. In addition, an electrode non-formation portion 21 where the external electrode layer 20 does not exist is present at least on the proximal end side of the region corresponding to the row 12 of the piezoelectric elements 11 of the piezoelectric element forming member 13. A plurality of slits 18 are formed in a length that reaches a region facing the electrode non-forming portion 21, and the external electrode layer 20 is separated for each piezoelectric element 11 by the slit 18 and the electrode non-forming portion 21, and adjacent to each other. An individual external electrode 22 that is electrically independent of the piezoelectric element 11 to be configured, and a common external electrode 23 that is electrically common to the adjacent piezoelectric element 11 are configured.

  Hereinafter, a method for forming such a piezoelectric element unit will be described. 3 is a cross-sectional view showing a manufacturing process of the piezoelectric element unit, FIG. 4 is a schematic view showing an example of a wire saw device, and FIG. 5 is a view of a piezoelectric element forming member fixed to a fixing jig. It is the schematic which shows a processing state.

  First, as shown in FIG. 3A, for example, piezoelectric material layers 15 such as lead zirconate titanate (PZT) and internal electrodes 16 and 17 are alternately sandwiched and stacked to form a piezoelectric element forming member. 13 is formed. Next, as shown in FIG. 3B, the external electrode layer 20 is formed on the surface of the piezoelectric element forming member 13 formed in this way. For example, in this embodiment, the external electrode layer 20 is formed in a predetermined region on the surface of the piezoelectric element forming member 13 by vapor-depositing an external electrode material through a mask member having a predetermined pattern. Of course, the material of the piezoelectric material layer 15 is not limited to lead zirconate titanate.

  Next, as shown in FIG. 3C, the piezoelectric substrate unit 10 is formed by bonding the fixed substrate 14 to the bottom surface of the piezoelectric element forming member 13 on the base end side. The fixed substrate 14 is preferably made of a material having a high specific gravity and a hard material, for example, a metal such as stainless steel (SUS) or a tungsten alloy because of a characteristic problem.

  Further, at this stage, the piezoelectric element forming member 13 is not formed with a piezoelectric element, and finally the piezoelectric element forming member 13 is cut into a comb-like shape to thereby form a piezoelectric element unit having a row 12 of piezoelectric elements 11. 10 That is, after the piezoelectric element forming member 13 is bonded to the fixed substrate 14, the piezoelectric element unit 10 is formed by forming a plurality of slits 18 in the piezoelectric element forming member 13 by a wire saw device.

  In the present invention, the step of forming the plurality of slits 18 in the piezoelectric element forming member 13 as described above, that is, the step of cutting the piezoelectric element forming member 13 into a comb-like shape is performed by a plurality of piezoelectric element units 10 (piezoelectric element forming). This is done with the members 13) arranged in parallel.

  Here, the wire saw device 100 used for processing the piezoelectric element forming member 13 includes, for example, a first to third rollers 101 to 103 and the first to third rollers 101 to 103 as shown in FIG. A plurality of piezoelectric element forming members 13 to be processed are provided below the wire 104 wound between the first roller 101 and the second roller 102. The table 105 is fixed by the fixing jig 200. The wire 104 is wound around the first roller 101 and the second roller 102 at a predetermined interval corresponding to each slit 18 formed in the piezoelectric element forming member 13, and both ends of the piezoelectric element forming member 13 are In the portion corresponding to, such as the portion where the slit 18 is not formed, it is wound around the first to third rollers 101 to 103. In the present embodiment, the wire saw device 100 in which one wire 104 is spirally wound around the first to third rollers 101 to 103 is exemplified. A wire saw device wound around the second rollers 101 and 102 corresponding to each slit may be used.

  Then, as shown in FIG. 5, a plurality of piezoelectric element forming members 13 fixed on the table 105 by the fixing jig 200 are wound around a pair of rollers, that is, a first roller 101 and a second roller 102. By moving the hooked wires 104 in contact with each other, the piezoelectric element forming members 13 are cut into comb-like shapes to form the rows 12 of the piezoelectric elements 11. That is, the first to third rollers 101 to 103 are rotated to move the wire 104 in the direction indicated by the arrow in the drawing, the table 105 is moved upward in the drawing, and the wire 104 is piezoelectrically fed while supplying slurry. A plurality of slits 18 are formed by contacting the element forming member 13.

  At this time, in the present invention, the height of the piezoelectric element forming member 13 disposed at the center between the first and second rollers 101 and 102 is higher than the height of the piezoelectric element forming member 13 disposed at both ends. It is trying to become.

  For example, in the present embodiment, the piezoelectric elements formed in parallel are formed on the basis of the bending amount of the wire 104 at the position corresponding to each piezoelectric element forming member 13 when the piezoelectric element forming members 13 are cut into comb teeth. The height of the member 13 relative to the table 105 is corrected. Here, the height of the piezoelectric element forming member 13 relative to the table 105 is a height when the piezoelectric element forming member 13 is fixed to the fixing jig 200. For example, in this embodiment, the height of the fixing jig 200 from the surface of the table 105 is determined. The height h1 to the tip of the fixed portion 201 on which the piezoelectric element unit 10 (piezoelectric element forming member 13) is placed is used as a reference. And the height of each fixing | fixed part 201 of the fixing jig 200 is correct | amended so that the height from the table 105 of each piezoelectric element formation member 13 becomes high, so that the bending amount of the wire 104 is large.

  Here, as shown in FIG. 5, the fixing jig 200 according to the present embodiment includes a plurality of fixing members 202 each having a fixing portion 201 on which the piezoelectric element unit 10 is placed in an inclined state. Become. Specifically, a plurality of types of fixing members 202 having different heights up to the tip of the fixing portion 201 are prepared, a predetermined fixing member 202 is selected according to the amount of bending of the wire 104, and they are connected. Thus, the fixing jig 200 is obtained. If the fixing jig 200 is formed by connecting a plurality of fixing members 202 in this manner, the height of each fixing portion 201 can be adjusted very easily. Of course, the structure of the fixing jig 200 is not particularly limited as long as the height of the piezoelectric element forming member 13 to be fixed relative to the table 105 can be adjusted according to the amount of bending of the wire 104.

  Specifically, the height of each fixing portion 201 is corrected as follows. First, with the height of each piezoelectric element forming member 13 kept constant, a step of cutting these piezoelectric element forming members 13 into comb teeth is performed, and the depth of the slits 18 formed in each piezoelectric element forming member 13 Measure. The depth of the slit 18 changes according to the amount of bending of the wire 104, and becomes shallower as the piezoelectric element forming member 13 located at the center (see FIG. 6). In this example, eleven piezoelectric element units 10 (piezoelectric element forming members 13) are arranged in parallel, and the horizontal axis is a number indicating the arrangement order of the piezoelectric element units 10. Next, based on the depth data of the slit 18, that is, based on the deflection amount of the wire 104, for example, a correction value for the height h <b> 1 of the piezoelectric element forming member 13 is determined as shown in the graph of FIG. 7. To do. Based on this correction value, the fixing member 202 is selected and connected as described above to form the fixing jig 200, thereby correcting the height of each fixing portion 201. For example, in this example, a maximum difference of 0.085 mm is caused in the height of each fixing portion 201, that is, the height of the piezoelectric element forming member 13.

  In a state where the height h1 of the piezoelectric element forming member 13 is corrected as described above, the movement of the table 105 (piezoelectric element forming member 13) is stopped by cutting the piezoelectric element forming member 13 into a comb shape. Even if the so-called stop cut is not performed, the depth of the slit 18 of each piezoelectric element forming member 13 can be made substantially constant as shown in the graph of FIG. Further, since it is not necessary to perform stop-cutting, the width of each slit 18 is also substantially constant, that is, the width of each piezoelectric element 11 is substantially constant. Therefore, according to the present invention, the displacement characteristics of each piezoelectric element 11 of each piezoelectric element unit 10 can be improved, and the displacement characteristics can be made uniform.

  Moreover, since the variation in the depth of the slit 18 formed in the piezoelectric element forming member 13 is reduced, the processing speed can be increased. For example, the processing speed of about 4 μm / sec can be increased to about 5 μm / sec by adopting the method of the present invention, which has conventionally been required to be processed at 4 μm / sec.

  In the present embodiment, the height of the piezoelectric element forming member 13 is corrected based on the amount of bending of the wire 104. However, for example, the height of the piezoelectric element forming member 13 is not based on the amount of bending of the wire 104. If the height of the piezoelectric element forming member 13 is made higher than the height of the piezoelectric element forming member 13 disposed on the end side, the stop-off time can be shortened. The characteristics can be improved.

  In the present embodiment, only the height of the piezoelectric element forming member 13 is adjusted based on the amount of bending of the wire 104. However, the present invention is not limited to this. For example, each piezoelectric element forming member 13 of the wire 104 The inclination angle of each piezoelectric element forming member 13 may be further corrected so that the contact angles are substantially the same. The contact angle between the wire 104 and each piezoelectric element forming member 13 is slightly different due to the bending of the wire 104, and this difference may slightly affect the depth of the slit 18, but the inclination angle of the piezoelectric element forming member, for example, By correcting the inclination angle of the fixed portion 201 with respect to the surface of the table 105, the depth of each slit 18 can be made more uniform.

  The piezoelectric element unit 10 thus formed is then connected to a drive wiring for supplying a signal for driving the piezoelectric element 11 and mounted on an ink jet recording head or the like.

  As mentioned above, although one embodiment of the present invention was described, of course, the present invention is not limited to this embodiment.

It is a perspective view of the piezoelectric element unit manufactured with the manufacturing method of this invention. It is the top view and sectional drawing of the piezoelectric element unit manufactured with the manufacturing method of this invention. It is sectional drawing which shows the manufacturing process of a piezoelectric element unit. It is the schematic which shows an example of a wire saw apparatus. It is the schematic which shows the processing state of the piezoelectric element formation member fixed to the fixing jig. It is a graph which shows the depth of the slit by the process without height correction. It is a graph which shows the correction amount of the height of a piezoelectric element formation member. It is a graph which shows the depth of the slit by the process with height correction.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Piezoelectric element unit, 11 Piezoelectric element, 13 Piezoelectric element formation member, 14 Fixed board | substrate, 18 Slit, 100 Wire saw apparatus, 101 1st roller, 102 2nd roller, 103 3rd roller, 104 wire, 105 table, 200 Fixing jig, 201 Fixing part, 202 Fixing member

Claims (6)

A method of manufacturing a piezoelectric element unit comprising a row of piezoelectric elements obtained by cutting an individual electrode layer and a piezoelectric element forming member having an individual electrode layer and a piezoelectric material layer into a comb shape,
A plurality of piezoelectric element forming members are arranged in parallel, fixed on a table by a fixing jig, and a wire wound around a pair of rollers is brought into contact with the plurality of piezoelectric element forming members so that each piezoelectric element forming member is combed. A row of the piezoelectric elements is formed by cutting into teeth, and at this time, the height of the piezoelectric element forming member arranged at the center part between the pair of rollers with respect to the table is arranged on both end sides. A method of manufacturing a piezoelectric element unit, wherein the height of the piezoelectric element forming member is higher than the height of the table. At least the height of each of the juxtaposed piezoelectric element forming members is corrected based on the amount of bending of the wire at the position corresponding to each piezoelectric element forming member when the piezoelectric element forming member is cut into a comb tooth shape. The method of manufacturing a piezoelectric element unit according to claim 1. 3. The method of manufacturing a piezoelectric element unit according to claim 2, wherein the height of the piezoelectric element forming member with respect to the table is increased as the bending amount of the wire is increased. Each piezoelectric element forming member is cut into a comb-teeth shape with each piezoelectric element forming member inclined with respect to the table, and at this time, the intersecting angle of each piezoelectric element forming member with the wire is the same. The method for manufacturing a piezoelectric element unit according to claim 1, wherein the angle of each piezoelectric element forming member is further corrected. A plurality of piezoelectric element forming members are used in the manufacture of a piezoelectric element unit comprising a piezoelectric element row in which individual electrode layers and piezoelectric element forming members each having an individual electrode layer and a piezoelectric material layer are separated into comb teeth. The piezoelectric element forming members are fixed on the table when the piezoelectric element forming members are cut into a comb-like shape by moving the wires wound around the pair of rollers in contact with each other. A fixing jig for
A fixing jig having a plurality of fixing portions on which the piezoelectric element forming members are respectively arranged, and the height of each fixing portion with respect to the table can be independently adjusted. The fixing jig according to claim 5, wherein a plurality of fixing members having the fixing portion are connected.

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