JPH01269532A - Manufacture of ceramic laminate - Google Patents

Abstract

PURPOSE:To facilitate a positioning even in case of circular work shape, by printing a predetermined patterned inner electrode on a ceramic green sheet, punching it in work-shape leaving a small slight portion thereof, laminating a required number of said sheets and pressing them, and then cutting off the joint portion. CONSTITUTION:Positioning holes 2 are provided in a tape 1 with a predetermined interval, then inner electrode are printed thereon with metal paste and the obtained tape is set in the constant feeding device of a press on which a cutting blade 4 having diagonally positioned cut parts are attached. By punching said tape with such cutting blade 4 with a predetermined interval, circular work shapes 5 are punched leaving the joining parts 6 which connect said work shapes 5 with said tape. A required number of such obtained tapes are laminated and cut with a cutting blade 7 corresponding to the cut parts of said circular cutting blade 4 with pressing the work part to cut off the joining parts. Therefore, circular ceramic laminates can be manufactured without difficult of positioning.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing a ceramic laminate, and more specifically, it relates to a method for manufacturing a ceramic laminate, and more specifically, it relates to a method for manufacturing a ceramic laminate. This invention relates to a lamination method that simplifies the process.

[Conventional technology]

A general method for manufacturing a ceramic laminate is as follows. After creating ceramic green sheets and printing internal electrodes, position them and punch them into the workpiece shape one by one.
Create segments. Stack the required number of segments and apply pressure to make them stick together. The ceramic laminate thus obtained is fired, machined, and formed into external electrodes to form an actuator or the like.

[Problem to be solved by the invention]

In a laminated ceramic body such as an actuator, a round shape can minimize the part shape if the workpiece has the same effective area as the piezoelectric element. However, when stacking round segments as described above, positioning is difficult. In other words, although the segments are round, the padding of the internal electrodes cannot be made into concentric circles due to the insulation between the laminated layers and the extraction of the external electrodes, so positioning in the circumferential direction is required. Because of its shape, positioning is difficult.

Although it is conceivable to make notches in the round segments for positioning, this is not preferable because it causes problems such as a reduction in the effective area of the workpiece and stress concentration.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a method for manufacturing a ceramic laminate that allows easy positioning even for round-shaped workpieces.

[Failure to solve the problem]

Therefore, in order to achieve the above object, the present invention includes a process of printing internal electrodes in a predetermined pattern on a ceramic green sheet, and punching the sheet into a workpiece shape, leaving only a small portion of the sheet as a joint, rather than the entire circumference. The present invention provides a method for producing a ceramic laminate, which includes a step of stacking a required number of sheets, and a step of pressurizing the stacked workpieces and cutting the joints to obtain a ceramic laminate.

[For production]

According to this method, even if the workpiece has a round shape, the ceramic green sheets to be laminated can have a shape other than a round shape, such as a tape shape, so positioning is easy. Moreover,
When punching out a workpiece after laminating tape-shaped green sheets, most of the shape of the workpiece has been punched out in advance, and only the joint portions need to be cut, making it possible to punch out the workpiece without difficulty.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings.

Please refer to FIG. Adding a binder (e.g. polyvinyl alcohol) to piezoelectric ceramic powder such as PZT,
Width 30mm using doctor blade method.

Form into a tape with a thickness of 0.5 mm. Positioning holes 2 are provided at predetermined intervals in the resulting tape. Then,
Print the internal electrodes with metal paste.

The tape 1 thus obtained is set in a constant feeding device of a press. Further, a cutting edge 4 having the shape shown in FIG. 2(a) is attached to the press. This cutting edge 4 is circular and has a notch on the diagonal. When the tape 1 is punched out at regular intervals with such a cutting edge 4, a round workpiece shape 5 is created as shown in FIG.
These round workpieces 5 are punched out, but a joint 6 remains in response to the chipping of the cutting edge 4, and is connected to the tape 1 at this joint 6.

As shown in FIG. 3, the tapes thus obtained are stacked in a required number, for example, 100 sheets. Next, while pressurizing the work part 5, as shown in FIG. 2(b), as shown in FIG.
A cutting edge 7 corresponding to the notch in the round cutting edge 4 cuts the joint 6 of the workpiece 5.

In this way, a laminate having the shape shown in FIG. 4 is obtained. This laminate is fired in a conventional manner and processed into an actuator.

In addition, after producing the tape as described above, punching it into a work shape having a joint part, and laminating the required number of tapes, the second
Instead of cutting with a cutting edge as shown in Figure (b), the workpiece may be pushed out with a punch having the same cross section as the workpiece shape.

The workpiece thus obtained is shown in Figure 5. This extrusion is easier to process than cutting the joint. The shape of the joint will be somewhat rough due to extrusion, but this will not be a problem since the width across flats will be processed afterwards.

゛[Oh, the method for manufacturing the laminate requires a sheet.
, )'s number of sheets are stacked and the entire circumference of the workpiece is punched out using the -2U method. However, since the PZT laminate used in automobile actuators has a thickness of 80 mm due to displacement, it is difficult to punch it out in one operation, as described below.

(a) When the cutting edge goes into the laminate, it plastically deforms the laminate, but since there is no place for the ceramic to escape and ceramic has low elasticity, the laminate eventually cracks.

(b) When pulling out the cutting edge, the ceramic sheet has adhesive strength, so it cannot be pulled out smoothly.

(C) The eject operation for taking out the laminate also tends to stick to the cutting edge due to the adhesive force of the ceramic, increasing the resistance and making it difficult to eject the laminate without damaging it.

In contrast, in the method of the present invention, the only part to be punched out after lamination is the joint, so there is sufficient space for the ceramic to escape with respect to (a) above, and no cracks occur. Also, (b
), (C), no eject operation is required.

〔Effect of the invention〕

According to the present invention, it is possible to manufacture a round ceramic laminate without difficulty in positioning.

Moreover, the number of man-hours required for manufacturing the laminate is reduced. Conventionally, positioning was required for each workpiece and each segment, but according to the present invention, positioning is only required when stacking tapes (segments) punched into a plurality of workpiece shapes. As a result, the number of man-hours involved in carrying, collecting, etc. the segments is also reduced.

[Brief explanation of the drawing]

Figure 1 is a perspective view showing a tape punched into the shape of a workpiece;
Figure 2 is a perspective view showing the shape of the cutting edge, Figure 3 is a perspective view showing sheet stacking, Figure 4 is a perspective view showing the final workpiece shape, and Figure 5 is the shape of the extruded workpiece. FIG. 1...Tape, 2...Positioning hole, 4
... Cutting edge, 5... Workpiece shape punching part, 6... Joint part, 7... Cutting edge.

Claims (1)

[Claims] 1. A step of printing a predetermined pattern of internal electrodes on a ceramic green sheet, a step of punching out the sheet into a workpiece shape leaving only a small portion of the sheet as a seam instead of the entire circumference, and a step of stacking the required number of sheets. and a method for manufacturing a ceramic laminate, which includes the steps of pressurizing the laminated workpieces and cutting the joints to obtain a ceramic laminate.