JP3971960B2 - Manufacturing method of ceramic parts - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a ceramic component, and more particularly to a method for manufacturing a ceramic component by laminating ceramic green sheets, firing a ceramic laminate having voids therein, and then performing cutting.
[0002]
[Prior art]
As a conventional ceramic component, for example, there is a frame 100 as shown in FIG. This frame 100 is used when producing a bimorph type piezoelectric / electrostrictive device. The manufacturing method of the frame 100 is manufactured by laminating a plurality of ceramic green sheets including thin plates, integrally firing a component intermediate body having a void inside, and then cutting. The frame 100 of such a piezoelectric / electrostrictive device, for example, in the case of a bimorph type, has a front surface formed in a substantially U shape. In this frame 100, both side portions are formed of ceramic thin plates 101 and 102. That is, the component intermediate is cut with a gap 103 formed between the ceramic thin plates 101 and 102 on both sides.
[0003]
[Problems to be solved by the invention]
However, as described above, when a cutting process is performed on an intermediate part having a laminated structure having a gap inside, even if the ceramic thin plates 101 and 102 shown in FIG. In some cases, it could not resist the movement and could be damaged due to vibration.
[0004]
Further, in the above-described piezoelectric / electrostrictive device frame 100, the ceramic thin plate 101 becomes a movable plate portion and has a shape having a free end, so that the flexible plate portion has flexibility, and the frame 100 is handled when the frame 100 is handled. There was a problem that it was difficult to hold. This problem is not limited to the bimorph type piezoelectric / electrostrictive device, but is also a problem that occurs in the same way in a unimorph type piezoelectric / electrostrictive device having a thin movable plate portion.
[0005]
As a measure to prevent such breakage of the ceramic thin plate, the wax is poured into the gap of the above-mentioned component intermediate in a melted state and solidified in the void, or the ceramic thin plate is fixed with an adhesive or the like. The cutting work was performed after making the wall thickness sufficient to resist the movement of the cutting tool during the cutting process.
[0006]
However, when wax is poured into the voids of the component intermediate and solidified, a slight gap is generated between the solidified wax and the ceramic thin plate due to volume shrinkage caused by this solidification, and the wax and the ceramic thin plate are integrated. There was a problem that slight vibrations were generated. For this reason, it has been necessary to inject an adhesive into the gap between the wax and the ceramic thin plate to integrate the ceramic thin plate with the wax. Thus, when using wax and an adhesive agent, the process of inject | pouring these waxes and an adhesive agent was complicated, and there existed a trouble that the removal process of wax etc. became complicated after cutting. In addition, since adverse effects on ceramic parts and the environment due to wax and the like are taken into consideration, new measures against such adverse effects have been required.
[0007]
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for manufacturing a ceramic part with a high yield by making the cutting process simple and reliable without increasing the number of steps.
[0008]
[Means for Solving the Problems]
A feature of the present invention is that a plurality of ceramic green sheets including a thin plate are laminated to form a void inside, and a component intermediate body in which a thin plate is arranged at a position facing the void is cut after integral firing, A method of manufacturing a ceramic component for producing a ceramic component, wherein when laminating a plurality of ceramic green sheets including the thin plate, a separator portion is disposed on an inner surface of the thin plate, and the thin plate and the separator portion A step of disposing and forming a firing inhibitor layer over a predetermined size on the opposite surface; a step of firing the component intermediate; and a step of cutting out the component intermediate together with the separator portion to form a cut-out component; Removing the separator from the cut-out component.
[0009]
In this invention, when laminating the ceramic green sheets, the separator portion is arranged on the inner surface of the thin plate facing the gap formed inside, so that the thin plate facing the gap is formed when cutting to form a cutout part. Can resist the movement of the cutting tool, so that vibration can be prevented from occurring in the thin plate. For this reason, a thin plate does not break.
[0010]
Further, in the present invention, since the firing inhibitor layer is interposed on the opposing surface of the thin plate and the separator portion, when the component intermediate is fired, the thin plate and the separator portion can be prevented from being integrally burned, and the cut-out component The separator portion can be easily removed.
[0011]
Therefore, according to the present invention, it is possible to easily and reliably perform the cutting without damaging the thin plate facing the gap, and it is possible to manufacture ceramic parts with a high yield.
[0012]
In this invention, after firing the component intermediate, an adhesive is injected into the gap where the firing inhibitor layer has disappeared, and the thin plate and the separator are fixed together. Preferably, the separator is removed by removing the adhesive from the cut-out component.
[0013]
Moreover, in this invention, after baking a component intermediate body, it presses from the outside, closely_contact | adheres a thin plate and a separator part, cuts out a component intermediate body with a separator part, forms a cut-out component, and removes a separator part from a cut-out component You may do that.
[0014]
Furthermore, in this invention, it is preferable that the component intermediate body includes a pair of ceramic thin plates with a gap therebetween. And as a baking inhibitor layer, a hard-to-sinter thing, for example, theobromine, an organic binder, resin, a hydrocarbon compound, carbon, etc. are mentioned. Especially, since theobromine sublimates, it does not interfere with the green sheet in the firing process and is preferable.
[0015]
In the present invention, the cut-out component can be applied to the frame of the actuator.
[0016]
Furthermore, the separator portion is preferably formed of a laminate of ceramic green sheets. By doing in this way, a separator part and a ceramic component can be produced in the same ceramic green sheet lamination process, and a separator part can be certainly formed with a small number of processes.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment in which the present invention is applied to a frame of a piezoelectric / electrostrictive device that functions as an actuator will be described with reference to the drawings. However, it should be noted that the drawings are schematic, and the thicknesses and ratios of the layers are different from actual ones. Moreover, the part from which the relationship and ratio of a mutual dimension differ also in between drawings is contained. Therefore, specific thicknesses and dimensions should be determined with reference to the following description.
[0018]
(Structure of ceramic parts)
First, prior to the description of the method for manufacturing a ceramic component, the structure of the piezoelectric / electrostrictive device 1 including the ceramic component will be described with reference to FIG. The piezoelectric / electrostrictive device 1 includes a frame 2 as a ceramic part and a pair of piezoelectric / electrostrictive elements 3 and 3.
[0019]
The frame 2 connects a pair of movable plate portions 4, 4 formed so as to face each other at a predetermined interval, and the movable plate portions 4, 4 connected to each other at one end side of the movable plate portions 4, 4. The fixed portion 5 formed as described above is integrally formed. The movable plate part 4 is formed of a ceramic thin plate. The fixing part 5 is formed of a ceramic laminate. That is, the frame 2 has a ceramic integrated structure in which the ceramic green sheet laminate is integrated by firing.
[0020]
The piezoelectric / electrostrictive element 3 is fixed by bonding with an adhesive (not shown) or firing without using an adhesive so as to straddle the fixed portion 5 and the movable plate portion 4 on both outer sides of the frame 2. ing. In the piezoelectric / electrostrictive element 3 shown in FIG. 1, a plurality of piezoelectric ceramic layers 6 and a plurality of electrode layers 7 are alternately laminated, and each electrode 7 is formed on two opposite sides of these laminates. External connection electrodes 8 and 9 are alternately connected in common and connected to an external circuit.
[0021]
(Manufacturing method of ceramic parts)
Next, a method for manufacturing the frame (ceramic part) 2 having the above structure will be described with reference to FIGS. The process flow of this embodiment is as shown in the flowchart of FIG. 2 to 5 show the region necessary for forming the laminate of the minimum unit for convenience of explanation of the manufacturing method.
[0022]
(A) First, as shown in FIGS. 2A to 2C, three types of ceramic green sheets 10, 11, and 12 each having a predetermined thickness are prepared, and each ceramic green sheet 10, 11, A ceramic paste (adhesive) (not shown) is applied to 12 predetermined portions. The ceramic green sheets 10 and 11 are thin plates, and the ceramic green sheet 12 is a relatively thick plate.
[0023]
(B) Next, as shown in FIGS. 2A, 2C and 8, the ceramic green sheets 10 and 12 are punched into a predetermined pattern to form ceramic green sheets S1 and S3. Further, as shown in FIGS. 2B and 8, the ceramic green sheet 11 is punched into a predetermined pattern to form the ceramic green sheet 13, and then the theobromine layer 14 as a firing inhibitor layer is formed on the surface of the predetermined region. Printing is performed to form the ceramic green sheet S2 (theobromine printing step). In addition, as shown in FIG. 2C and FIG. 8, a plurality of ceramic green sheets S3 (three in the present embodiment) are temporarily laminated. These ceramic green sheets S1, S2, and S3 are formed bodies before firing.
[0024]
Here, the punching pattern of each ceramic green sheet S1, S2, S3 will be described. First, as shown in FIGS. 2A and 3, the ceramic green sheet S1 is formed with a slit 15 on one side. The slit 15 is formed to facilitate the removal of a separator portion described later. Further, the ceramic green sheet S2 forms a part of a separator portion described later, and is punched with a rectangular opening portion 16 for separation from the frame 2 shown in FIG. Further, an opening 17 having the same planar shape as the opening 16 is punched into the ceramic green sheet S3 at a position corresponding to the opening 16 of the ceramic green sheet S2.
[0025]
(C) Next, as shown in FIGS. 3 and 8, ceramic green sheets S1 and S2, a temporary laminate of a plurality of ceramic green sheets S3, and ceramic green sheets S2 and S1 are sequentially stacked and shown in FIG. Such a primary part intermediate 18 is produced (main lamination step). At this time, the ceramic green sheet S2 is coordinated so that the printed theobromine layer 14 is positioned on the outer ceramic green sheet S1 side.
[0026]
(D) After that, as shown in FIG. 4, the laminated primary part intermediate 18 is heated at a rate that does not leave the organic content of each material layer, and is baked. The secondary part intermediate body 19 having the structure shown is formed (firing step). As a result, the laminated ceramic green sheets S1, S2, and S3 are fired and integrated. In this firing, the region in which the theobromine layer 14 is interposed between the ceramic green sheet S1 and the ceramic green sheet S2 is not integrally joined even by firing. For convenience of explanation, in FIGS. 4 to 6, reference numerals 20, 21, and 22 are sequentially attached to ceramic plates obtained by firing ceramic green sheets S <b> 1, S <b> 2, and S <b> 3.
[0027]
(E) The theobromine layer 14 disappears by firing, and an adhesive is injected into the gap formed between the ceramic plate 20 and the ceramic plate 21 to bond the ceramic plates 20 and 21 together. The adhesive is injected from the slit 15 of the ceramic plate 20.
[0028]
(F) Next, the secondary part intermediate body 19 is cut along the one-dot chain line a shown in FIG. 4 (cutting step). This cutting can be performed using a known wire saw or rotating blade. Then, as shown in FIG. 5, the gap 23 formed in the secondary part intermediate 19 is exposed. The gap 23 is formed by continuously forming the openings 16 and 17 formed in the ceramic green sheets S2 and S3. The adhesive layer 24 injected between the ceramic plates 20 and 21 is exposed on the cut surface shown in FIG. In this state, a separator portion 25 made of a laminate of ceramic plates 21 and 22 is interposed in the vicinity of the slit 15 of the ceramic plate 20 sandwiching the gap 23. Moreover, since the ceramic plate 21 constituting the separator portion 25 and the ceramic plate 20 serving as the movable plate portion 4 are fixed by the adhesive layer 24, the ceramic plate 20 can be prevented from vibrating during cutting, and the ceramic plate Damage to the plate 20 can be prevented.
[0029]
(G) Subsequently, as shown in FIGS. 5 and 8, the secondary part intermediate body 19 is cut into a predetermined thickness along the alternate long and short dash line b, and the intermediate part of the tertiary part as shown in FIG. The body 26 is produced. At this time, in the tertiary part intermediate body 26, the frame 2 as the ceramic part of the piezoelectric / electrostrictive device 1 described above and the separator part 25A cut out from the separator part 25 are bonded by the adhesive layer 24. It has a structure.
[0030]
(H) Next, as shown in FIG. 8, the third part intermediate body 26 cut in the above process is immersed in a solvent, the adhesive layer 24 is dissociated and removed, and the separator portion 25A is removed. A frame 2 as shown in FIG. 7 can be obtained. Thereafter, the frame 2 is washed to complete the manufacture of the frame 2 that is a ceramic part.
[0031]
In the green sheet punching step in the manufacturing method described above, the length of the movable plate portion 4 of the frame 2 as the ceramic component can be set by adjusting the position where the slit 15 is formed in the ceramic green sheet S1. The slit 15 has a function as an opening for allowing the adhesive to enter after firing.
[0032]
Further, by setting the shape and size of the openings 16 and 17 formed in the ceramic green sheets S2 and S3, it is possible to set how much the separator 25 is inserted into the frame 2. it can. Specifically, if the overlapping area of the separator portion 25 and the movable plate portion 4 of the frame 2 is large, the gap 23 becomes narrow, but the generation of vibration of the ceramic plate 20 that becomes the movable plate portion 4 is suppressed in the cutting process. On the other hand, the formation area of the adhesive layer 24 is widened.
[0033]
On the other hand, when the lengths of the openings 16 and 17 are set long, the overlapping area between the separator portion 25 and the movable plate portion 4 of the frame 2 becomes small, the length of the gap 23 becomes long, and the ceramic plate 20 easily vibrates. Tend to be. For this reason, it is preferable to set the sizes of the openings 16 and 17 in consideration of the thickness of the ceramic plate 20 and the width dimension of the movable plate portion 4 of the frame 2 to be manufactured.
[0034]
Furthermore, the theobromine layer 14 is formed on the ceramic green sheet S2 described above, and when the laminate as shown in FIG. 4 is formed, the internal voids 23 are sealed, but theobromine vaporizes during firing. Thus, an exhaust hole is formed, and the generated gas in the gap 23 can be exhausted. Moreover, this has the effect | action which maintains the flat plate shape of ceramic green sheet S1 which is a thin plate. Further, since theobromine is applied in a paste state, even when the back surface of the ceramic green sheet S1 which is a thin plate is not flat, the gap between the ceramic green sheets S1 and S2 can be filled by setting the film thickness to an arbitrary thickness. it can.
[0035]
(Other embodiments)
Although the embodiment of the present invention has been described above, it should not be understood that the description and the drawings, which constitute a part of the disclosure of the above embodiment, limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.
[0036]
For example, in the case of manufacturing the ceramic component shown in FIG. 1, after obtaining the secondary component intermediate 19 and before the cutting step, the piezoelectric / electrical electrode is applied to a predetermined position on the upper surface of the ceramic plate 20 that becomes the movable plate portion 4. The separator portion 25 has an effect of preventing cracking of the thin plate against the stress applied to the ceramic plate 20 which is a thin plate during the printing after the strain element 3 is formed by printing.
[0037]
Furthermore, in the above-described embodiment, after the theobromine layer 14 disappears by firing, an adhesive is injected from the slit 15 of the ceramic plate 20, and the ceramic constituting the ceramic plate 20 and the separator portion 25 by the adhesive layer 24. Although the plate 21 is fixed, if the ceramic plate 20 is pressed against the ceramic plate 21 at the time of cutting, vibration generation of the ceramic plate 20 can be suppressed. Therefore, the step of forming the adhesive layer 24 may be omitted.
[0038]
In the embodiment described above, the movable plate portion 4 of the frame 2 to be manufactured has a flat plate shape. However, as shown in FIG. 9 or FIG. 10, opposed inner surfaces of the pair of movable plate portions 4 of the frame 2. Needless to say, the protrusion 4A may be formed on the surface. In this case, a gap is formed around the protrusion 4A, but the gap can be filled by applying the theobromine layer 14 thickly.
[0039]
FIG. 9 is a perspective view showing a main part of a laminated type in which one laminated body to be the frame 2 and one laminated body to be the separator portion 25 are combined. FIG. 10 is a main part perspective view showing a laminated type in which two laminated bodies to be the frame 2 face each other and two separator parts 25 are integrally laminated therebetween. is there.
[0040]
Furthermore, in the above-described embodiment, the description has been made focusing on the area necessary for forming the laminate of the minimum unit. However, each of the various ceramic green sheets S1, S2, S3 has a lot of minimum in the ceramic green sheet fabric. A unit in which the slits 15 and the openings 16 and 17 are formed may be used.
[0041]
In the above-described embodiment, the method for manufacturing a ceramic component according to the present invention has been described by applying it to the manufacture of the frame 2 of the piezoelectric / electrostrictive device 1. Of course, the electrostrictive element 3 may be applied to the cutting of the one formed by printing.
[0042]
Furthermore, the present invention is applied not only to the manufacture of a frame of a piezoelectric / electrostrictive device, but also to the manufacture of a ceramic component having a configuration including a pair of ceramic thin plates sandwiching a gap that is likely to generate vibrations upon cutting. Can do.
[0043]
【The invention's effect】
As is clear from the above description, according to the present invention, the separator portion for suppressing the vibration of the ceramic thin plate can be formed simultaneously with the laminated body forming the ceramic component, so that the cutting process can be easily performed without increasing the number of steps. And it can be done reliably. As a result, it is possible to realize a method for manufacturing a ceramic part with a high yield by suppressing the occurrence of breakage in the ceramic thin plate.
[Brief description of the drawings]
FIG. 1 is a perspective view of a piezoelectric / electrostrictive device including a frame manufactured by applying a method of manufacturing a ceramic component according to the present invention.
FIGS. 2A to 2C are explanatory views showing a production process of a ceramic green sheet in an embodiment of a method for producing a ceramic component according to the present invention.
FIG. 3 is an exploded perspective view showing a ceramic green sheet laminating step in the embodiment of the method of manufacturing a ceramic component according to the present invention.
FIG. 4 is a perspective view of a main part of a laminated body or a fired body in an embodiment of a method for manufacturing a ceramic component according to the present invention.
FIG. 5 is a cross-sectional view of a principal part showing a cutting step in the embodiment of the method of manufacturing a ceramic component according to the present invention.
FIG. 6 is a perspective view of a third part intermediate body cut in the present embodiment.
FIG. 7 is a perspective view showing a frame manufactured in the present embodiment.
FIG. 8 is a flowchart showing manufacturing steps of the present embodiment.
FIG. 9 is a perspective view of a main part showing another embodiment according to the present invention.
FIG. 10 is a perspective view of a main part showing another embodiment according to the present invention.
FIG. 11 is a side view showing a frame of a conventional piezoelectric / electrostrictive device.
[Explanation of symbols]
2 Frame 4 Movable plate part 10, 11, 12, 13, S1, S2, S3 Ceramic green sheet 14 Theobromine layer (firing inhibitor layer)
15 Slit 16, 17 Opening 18 Primary part intermediate 19 Secondary part intermediate 20, 21, 22 Ceramic plate 23 Gap 24 Adhesive layer 25, 25A Separator part 1 Third part intermediate

Claims (7)

A plurality of ceramic green sheets including a thin plate are laminated to form a void inside, and a component intermediate in which the thin plate is arranged at a position facing the void is integrally fired and then cut to produce a ceramic component. A method for manufacturing a ceramic component, comprising:
When laminating a plurality of ceramic green sheets including the thin plate, a separator portion is disposed on the inner surface of the thin plate, and a firing inhibitor layer is disposed on a facing surface of the thin plate and the separator portion over a predetermined dimension. A forming step;
Thereafter, firing the component intermediate;
Cutting out the component intermediate together with the separator part to form a cut-out component;
Removing the separator from the cut-out component;
A method of manufacturing a ceramic component comprising: A method of manufacturing a ceramic component according to claim 1,
After firing the component intermediate, injecting an adhesive into the gap where the firing inhibitor layer has disappeared, and fixing the thin plate and the separator portion,
A method of manufacturing a ceramic component, comprising: cutting out the component intermediate together with the separator portion to form a cut-out component; removing the adhesive from the cut-out component; and removing the separator portion. A method of manufacturing a ceramic component according to claim 1,
After firing the component intermediate, pressing from outside, the thin plate and the separator portion are in close contact,
Cut out the part intermediate together with the separator part to form a cut out part,
A method of manufacturing a ceramic part, wherein the separator part is removed from the cut-out part. A method for manufacturing a ceramic component according to any one of claims 1 to 3,
The method of manufacturing a ceramic component, wherein the component intermediate includes a pair of ceramic thin plates sandwiching the gap. A method of manufacturing a ceramic component according to claim 1,
The method for manufacturing a ceramic component, wherein the firing inhibitor layer is made of theobromine. A method of manufacturing a ceramic component according to claim 1,
The method of manufacturing a ceramic component, wherein the cut-out component is an actuator frame. A method of manufacturing a ceramic component according to claim 1,
The separator part is formed of a laminated body of the ceramic green sheets.

Images