JPH0416030B2 - - Google Patents

Abstract

PURPOSE:To increase junction areas connecting between metallic protrusions and a side leas wire and combine them without causing defective junction by performing a lapping at each tip of the metallic protrusions, thereby arranging so that tips of the metallic protrusions may lie on the same plane. CONSTITUTION:After forming metallic protrusions 3 processed by Ni plating at end edges of internal electrodes 200 of a laminate body 100, a lapping processing is carried out at uneven tips of the metallic protrusions and a flat plane is formed at the tip parts after making tip parts of uniform height. Subsequently, thin solder is applied to the metallic protrusions 3 as well as to the surface of the side lead wire 4 and its lead wire 4 is placed on a line of the metallic protrusions that are composed of the metallic protrusions 3 and is pressed by heating with a metal pressure attachment member. Further, the end parts of the side lead wire 4 are fixed to metallic pieces 6 that are bonded to a dummy plate 5 with soldering means and the like.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a laminated piezoelectric material and a method for manufacturing the same. expand and contract,
The present invention relates to a laminated piezoelectric body that acts as an actuator and a method for manufacturing the same.

[Technical background]

The inventors of the present application have previously provided a laminated piezoelectric material as shown in FIG. 8 in Japanese Patent Application No. 61-200111.

In the laminated piezoelectric body shown in FIG. 8, a plurality of piezoelectric plates 802 are laminated and the piezoelectric plates 802 are fixed and integrated with an internal electrode 800 disposed between them to form a laminated body. Then, in the axial direction of the outer periphery of this laminate, every other internal electrode 800 is electrolessly plated to form a row of metal protrusions 803. The row of metal protrusions formed on this internal electrode has
A side lead wire 804 is connected, and a voltage from an external power source is applied to the metal protrusion 80 from this side lead wire 804.
3 to each piezoelectric plate 802.

[Problem that the invention seeks to solve]

However, in a laminated piezoelectric body as shown in FIG.
It is difficult to form all the protrusions 03 with the same amount. Therefore, when connecting the side lead wire 804 to the metal protrusion 803, if there is a metal protrusion with a small amount of protrusion, such as the metal protrusion 803a, there is a problem that the side lead wire 804 is not properly connected. .

Therefore, if the side lead wire 804 and the metal protrusion 803a are not well connected in this way, not only will no voltage be supplied to the piezoelectric plate 802, but also the bonding strength between the side lead wire 804 and the metal protrusion 803 will decrease. There's a problem.

In addition, in this laminated piezoelectric body, the side lead wire 8
04 and an external power source is directly connected to the side lead 804 by means such as soldering. Therefore, when an external force acts on this external lead wire, the external force is directly transmitted to the side lead wire 804, and the side lead wire 804
There is also a concern that the connection between the metal protrusion 803 and the metal protrusion 803 may become disconnected. Moreover, there is also a concern that the connection between the external lead wire and the side lead wire 804 may come off at the same time.

Furthermore, in such a laminated piezoelectric body, since the tip of the metal protrusion 803 is rounded, the bonding area between the metal protrusion 803 and the side lead wire 804 is extremely small. Therefore, there is a problem that sufficient bonding strength between the metal protrusion 803 and the side lead wire 804 cannot be ensured.

[Means for solving problems]

The present invention aims to solve the above-mentioned problems, and the following measures have been taken to solve the problems. In other words, there is a laminate in which a plurality of piezoelectric plates are laminated, and the piezoelectric plates are fixed and integrated with internal electrodes arranged between them, and a line is formed in the axial direction of the outer periphery of this laminate in every other internal electrode. a first metal protrusion row formed with metal protrusions, the tips of which are lapped so that the tips of the metal protrusions are located substantially on the same plane; and the first metal protrusion row. forming a row of metal protrusions on the internal electrode on which the first row of metal protrusions is not formed, spaced apart in the outer circumferential direction of the laminate;
a second row of metal protrusions whose tips are lapped so that the tips of the metal protrusions are located on substantially the same plane; a dummy plate disposed at the upper and lower ends of the laminate; a side lead wire electrically connected to the protrusion of each of the first metal protrusion row and the second metal protrusion row; and a side lead wire fixed to the dummy plate, with an end of the side lead wire electrically connected a conductive metal piece that is connected and fixed; an external lead wire that is electrically connected and fixed to the conductive metal piece and electrically connects an external power source to the conductive metal piece; and the first and second
The laminated piezoelectric body is provided with an insulating coating layer formed between each metal protrusion of the metal protrusion rows and insulating the internal electrodes existing between the metal protrusion rows.

Further, by stacking a plurality of piezoelectric plates with internal electrodes interposed therebetween, and forming metal protrusions projecting outward from the piezoelectric plates on every other internal electrode, the first
a metal protrusion row is formed, and a metal protrusion that protrudes outward from the piezoelectric plate is spaced apart from the first metal protrusion row in the outer circumferential direction to an internal electrode on which the first metal protrusion row is not formed. 1
a second row of metal protrusions is formed by forming the first and second rows of metal protrusions every other time; A solder layer is formed on the surface of the row of metal protrusions, and side lead wires coated with solder are brought into contact with each of the first and second metal protrusions on which the solder layer is formed, and the crimping jig is heated to a high temperature. By pressing on this side lead wire, the side lead wire is connected to the first and second side lead wires.
A method of manufacturing a laminated piezoelectric body is provided, in which the piezoelectric body is fixed to a row of metal protrusions, and an external lead wire is connected to the side lead wire.

[Operation and effect of the invention]

In the present invention, the tips of the metal protrusions are lapped so that the tips are located on substantially the same plane, which increases the bonding area with the side lead wires. The wires can be well connected to each other without causing bonding defects.

In addition, the side lead wires and the external lead wires are not directly connected to each other, but are each connected to a metal piece, so even if an external force is applied to the external lead wires, that force will be applied directly to the side lead wires. It has no effect on the line. Therefore, there is no problem that the joint between the side lead wire and the metal protrusion separates due to this external force.

Further, since the side lead wires are connected and fixed to each row of metal protrusions at once, the workability is very good.

〔Example〕

FIG. 1 is a perspective view showing an embodiment of the present invention.
In FIG. 1, 2 is a piezoelectric plate, 200 is an internal electrode that fixes and integrates the piezoelectric plate 2, and 3 is a plated plate on every other internal electrode 200 on one side of a laminate 100 consisting of the piezoelectric plate 2 and the internal electrodes 200. 4 is a side lead wire connected to the first row of metal protrusions made up of the plurality of metal protrusions 3; 5 is a dummy plate disposed at the upper and lower ends of the laminate 100; 6 is a metal protrusion formed by A conductive metal piece 7 is fixed to the dummy plate 5 and to which the end of the side lead wire 4 is electrically connected, and is an external lead wire electrically joined to the metal piece 6.

FIG. 2 shows a plurality of piezoelectric plates 2 stacked together.
It is a diagram showing a state in which the three sheets are taken out and transferred to each other. This piezoelectric plate 2 is made by firing a molded ceramic sheet such as PZT, polishing the outer periphery,
The surface is lapped, and internal electrodes 200 are formed by screen printing electrode paste on the surface. At this time, the piezoelectric plate 2 is formed by cutting the opposing circumferential surfaces of a disk (about 15 mm in diameter) parallel to each other, as shown in the figure, to form side surfaces for drawing out the protruding electrodes. In addition, the internal electrodes 200 are formed using two types of electrical pastes, and one pattern 201 is made of silver paste and palladium (or Fe, Co, Ni,
Group metals such as Ru, Os, Ir, Pt, etc.) from 5 to
The other putter 202 uses a paste containing silver paste mixed with 5 to 30 wt% of lead (or Sb, Sn, Zn, etc.).
Of the outer periphery of the piezoelectric plate 1, the pattern 201 contacts only the end surface for leading out the external electrode (one of the side surfaces cut parallel to the circumferential surface of the disk), and the pattern 202 contacts the remaining outer periphery. ing.

This piezoelectric plate 2 is dried at 100° C., and a predetermined number of sheets are stacked so that the pattern 201 is placed at the same position on every other sheet as shown in FIGS. 2 and 3. Then, while applying a load of about 1 kg/cm ² to the laminate 100, the temperature is raised to 600° C. in an oxygen atmosphere to bake the paste. At this time, the piezoelectric plate 2 is fixed and integrated by the glass contained in the electrode paste.

The integrated laminate 100 is electrolessly plated as follows. The first method is to perform alkaline degreasing with an alkaline degreasing solution (manufactured by Henkel Hakusui), rinse with water, soak in hydrochloric acid (1:1) for 1 to 2 minutes, rinse with water, and use hypophosphorus at approximately 80℃. Approx. to acid soda
Leave on for 10 minutes. And the height of metal protrusions 3 and 9 is
S780 at about 90℃ until 50-100 micrometers
Soak in electroless plating solution (manufactured by Nippon Kanizen Co., Ltd.).

The second method is to first mask the areas you do not want electroless plating with Teflon tape or the like, and then expose only the areas you want to plate. Then, perform alkaline degreasing with an alkaline degreasing solution (manufactured by Henkel Hakusuisha) and wash with water. Then, soak in hydrochloric acid (1:1) for 1 to 2 minutes, wash with water, and use active solution No. 3 at about 60℃.
(manufactured by Nippon Kanigen Co., Ltd.) for 10 minutes and then washed with water.
Then, soak it in hydrochloric acid (1:1) for 1 to 2 minutes,
Wash with water, soak in sodium hypophosphite at about 80°C for about 10 minutes, soak in SB/55 electroless plating solution (manufactured by Nippon Kanigen Co., Ltd.) at about 65°C for about 10 minutes, and wash with water. Then, it is immersed in S780 electroless plating solution at about 90° C. until the height of the metal protrusion 9 becomes 50 to 100 microns. Then, when the masking is complete, remove the mask.

When plating is performed, metal protrusions 3 and 9 made of nickel plating are formed on the edges of every other internal electrode 200 on each of the opposing surfaces of the laminate 100, as shown in FIGS. 1 and 3. In this electroless plating, the pattern 201 is activated by palladium, so the plating adheres well to the pattern 201, but the plating does not easily adhere to the pattern 202 because lead acts as a catalyst poison. Metal protrusions 3 and 9 as shown in FIG. 3 are formed.
The heights of the metal protrusions 3 and 9 formed in this way are uneven as shown in FIG. The flat parts 301 and 901 are formed at the tips thereof. In this way, the metal protrusions 3 and 9 are lapped to form the flat part 3.
After forming 01 and 901, it is washed with water, dried, and the side lead wires 4 are attached. Attachment of this side electrode is performed in the following manner.

First, the piezoelectric body 100 with the protrusions formed as described above is immersed in flux and passed through a solder layer whose temperature is controlled at 250°C.
Apply a thin layer of solder to the

In addition, the side lead wire 4 is made into a flat plate shape as shown in FIG. 4(b) by applying pressure from the top and bottom of the round bar 401 as shown in FIG. 4(a). . Then, as shown in FIG. 4(b), the flat side lead wire 4 is dipped in flux and passed through a solder layer to apply a thin layer of solder to the surface of the side lead wire. Then, the side lead wires are placed on the first metal protrusion row and the second metal protrusion row made up of the metal protrusions 3 and 9 described above, and the two are bonded by thermocompression using a metal pressure bonding member heated to 250°C. The solder adhering to the surface of the metal protrusion is melted, and the side lead wire 401 is fixed onto the metal protrusion row.

In this way, dummy plates 5 having the same outer circumferential shape as the piezoelectric plate 2 and a slightly thicker thickness are arranged at the upper and lower ends in the stacking direction of the stacked body 100 to which the side lead wires 4 are connected. And this dummy board 5
There is a bottomed hole 50 with a diameter of approximately 1 mm in the side notch.
1.

The metal piece 6 is a strip-shaped piece made of conductive metal, and a metal pin 8 having an outer diameter of about 1 mm is spot-welded to the metal plate 6 (FIG. 6).
Then, a metal pin 8 spot-welded to this metal piece 6 is attached to a hole 501 made in the above-mentioned dummy plate 5.
and secure them both with adhesive.

The end portion of the side lead wire 4 is fixed to the metal piece 6 fixed to the dummy plate 5 in this manner by means of soldering or the like. After the metal piece 6 is fixed to the dummy plate 5 in this manner, the laminate 100 is placed in a mold coated with a mold release agent. Then, adhesive epoxy resin, silicone, fluorosilicone, or the like is poured into the gap formed between the inner surface of the mold and the outer peripheral surface of the laminate 100 to form an insulating coating layer on the outer peripheral surface of the laminate 100. This insulating coating layer is formed between the metal protrusions of the first metal protrusion row made up of metal protrusions 3 and the second metal protrusion row made up of metal protrusions 9, and covers the internal electrodes present between each metal protrusion row. Insulated.

Although the side lead wire 4 shown in FIG. 1 has a straight flat plate shape, it may have a meandering shape as shown in FIG. The side lead wire may be formed into a spiral shape as shown in (b) of the figure.

Further, in the above example, the metal piece 6 was made into a rectangular strip, but as shown in FIG. It's okay. In this case, as shown in FIG. 7, a connecting pin 8 is spot welded to one piece 6a of the substantially doglegged metal piece 6, thereby fixing it to the dummy plate 5. Also, this one piece 6
The side lead wire 4 is fixed to a by means such as soldering. On the other hand, a side lead wire 7 is electrically connected and fixed to the other piece 6b of the metal piece 6 by means such as soldering. By forming the metal piece 6 in such a shape, the metal piece 6 can also have elasticity. Therefore, even if an external force acts on the external lead wire 7, this external force can be absorbed by the elastic deformation of the metal piece 6.

[Brief explanation of drawings]

Figure 1 is a perspective view of a laminated piezoelectric body, Figure 2 is a perspective view of a single piezoelectric plate, Figure 3 is a front view of the laminated piezoelectric body, and Figure 4 is a perspective view showing the forming process of side lead wires. , Figure 5 is a schematic diagram showing the side lead wires, Figure 6 is a schematic diagram showing the side lead wires.
7 is a partial perspective view of a laminated piezoelectric body, and FIG. 8 is a front view of a conventional laminated piezoelectric body. 2...Piezoelectric plate, 3...Metal protrusion, 4...Side lead wire, 5...Dummy plate, 6...Metal piece, 7...
External lead wire.

Claims (1)

[Scope of Claims] 1. A laminate in which a plurality of piezoelectric plates are laminated and the piezoelectric plates are fixed and integrated with internal electrodes arranged between them; a first row of metal protrusions formed on the internal electrode, the tips of each of the metal protrusions being lapped so that the tips are located on substantially the same plane; forming a row of metal protrusions on the internal electrode on which the first metal protrusion row is not formed, spaced apart from the metal protrusion row in the outer circumferential direction of the laminate;
a second row of metal protrusions whose tips are lapped so that the tips of the metal protrusions are located on substantially the same plane; a dummy plate disposed at the upper and lower ends of the laminate; a side lead wire electrically connected to the protrusion of each of the first metal protrusion row and the second metal protrusion row; and a side lead wire fixed to the dummy plate, with an end of the side lead wire electrically connected a conductive metal piece that is connected and fixed; an external lead wire that is electrically connected and fixed to the conductive metal piece and electrically connects an external power source to the conductive metal piece; and the first and second
A laminated piezoelectric body comprising an insulating coating layer formed between each metal protrusion of a metal protrusion row and insulating an internal electrode existing between each metal protrusion row. 2. Laminating a plurality of piezoelectric plates with internal electrodes interposed therebetween, and forming metal protrusions projecting outward from the piezoelectric plates on every other internal electrode.
a metal protrusion row is formed, and a metal protrusion that protrudes outward from the piezoelectric plate is spaced apart from the first metal protrusion row in the outer circumferential direction to an internal electrode on which the first metal protrusion row is not formed. 1
a second row of metal protrusions is formed by forming the first and second rows of metal protrusions every other time; A solder layer is formed on the surface of the row of metal protrusions, and side lead wires coated with solder are brought into contact with each of the first and second metal protrusions on which the solder layer is formed, and the crimping jig is heated to a high temperature. By pressing on this side lead wire, the side lead wire is connected to the first and second side lead wires.
A method for manufacturing a laminated piezoelectric body, which is fixed to a row of metal protrusions, and an external lead wire is connected to the side lead wire.