JPS58196072A - Electrostrictive effect element - Google Patents

Abstract

PURPOSE:To obtain an element of large strains by a method wherein metallic films in contact with internal electrode plates are formed on the side surfaces of a lamination body wherein the end surfaces of the internal electrode plates are exposed, and these metallic films are connected to each other. CONSTITUTION:The internal electrode plate 31 is formed on the surface of an electrostrictive material film 1. Next, these are laminated in a fixed number and formed into an integral body by thermal press. The end surfaces of the electrode plate 31 are exposed on side surfaces. Then, Au pastes 32 and 32' are baked so as to contact the end surface of each electrode plate 31. The pastes 32 and 32' contact the electrode plates 31 at intervals of a layer. Lead wires are connected to the pastes 32 and 32' and thus connected to external terminals A and B.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the structure of an electrostrictive element that utilizes the longitudinal effect.

When an element having a double layered chip capacitor structure as shown in FIG. 1 is constructed using a material having a large electrostrictive effect, an electrostrictive effect element that generates a large strain at a low voltage can be obtained. That is,
As shown in FIG. 1(a), a film or thin plate made of an electrostrictive material 10 is connected to a positive internal electrode plate 2. Negative internal electrode plate 2'
In this structure, the internal electrode plates 2, 2' are connected to the external electrodes 3, 3', respectively. However, in the above-mentioned conventional electrostrictive effect element, as can be understood from the plan view of FIG. In the surrounding area, both electrodes are not subject to gravity. Therefore, when a voltage is applied between the external electrodes 3 and 3', the electric field strength is strong only in the area where the electrodes overlap.
The electric field strength in the surrounding area is weak. For this reason, there is a drawback that not only the peripheral portion of the element does not deform, but also the deformation of the entire element is inhibited, making it impossible to obtain the amount of strain specific to the material. Furthermore, there is a drawback that stress concentration occurs at the boundary between the deformed part and the undeformed part, and the mechanical Km element is destroyed by high voltage application, repeated application, long-time application, etc.

In order to improve the above-mentioned drawbacks, Figs. 2(a) and (b)
It is possible to create a structure as shown in K. That is,
As shown in Figure (a) K, one internal electrode plate 2.2' is alternately formed and laminated on the entire surface of the electrostrictive material film (or thin plate) 1, and the ends of the plurality of internal electrode plates 2 are mutually connected. The internal electrodes l11t' are connected to the external terminal A, and the internal electrodes l11t' are connected to the external terminal B. Therefore, as shown in Figure (b) K, the internal electrode plates 2 and 2' are formed on the entire surface of the element, so when a voltage is applied to the electrode terminals M and B, the electric field distribution within the electrostrictive material film l changes. Uniformly, the element deforms uniformly,
No stress concentration occurs.

In other words, the element exhibits an amount of deformation that is almost inherent to the material and becomes difficult to break. However, since the internal electrode plates 2 and 2'Fi are close to each other, the internal electrode plates 2 and 2'
It is very difficult to make electrical connections between them.

The object of the present invention is the above-mentioned situation K11l! Therefore, it is an object of the present invention to propose a structure of an electrostrictive effect element in which internal electrode plates formed on the entire surface of the element can be alternately and easily and stably connected to external electrode plates.

The electrostrictive effect element of the present invention has an internal electrode plate formed over the entire surface thereof, and several thin plates of electrostrictive material of the same size are laminated, and the end face of the internal electrode plate is placed on the side WJ. A metal film having a small area that contacts each of the internal electrode plates is formed on the exposed side surface of the laminate, and the internal electrode plates are electrically connected every other layer by lead wire connections between the metal films. It is characterized by

Next, one embodiment of the present invention will be explained in detail with reference to the drawings.

FIG. 3 is a sectional view showing one embodiment of the present invention. That is, first, magnesium lead niobate P b (iig,
, 5Nbz73) A pre-sintered powder of an electrostrictive material mainly composed of Os is added to the organic binder of Kik11 and dispersed in an organic solvent to prepare a slurry, and the slurry is used to manufacture a normal multilayer chip capacitor. The coating is applied to a Mylar film to a thickness of several 100 microns, dried, and then peeled off from the Mylar film to form an electrostrictive material film. The internal electrode plate 31 is formed by screen printing platinum paste on the surface of the electrostrictive material film %1. The internal electrode plate 31
is formed, and a predetermined number of large strained material films \1 (usually number 10) are formed.
1,250℃ after laminating them and combining them into one body by heat pressing.
If sintered at a temperature of
A laminate is obtained.

When the side surface of the laminate is cut to a required size, the end surface of the internal electrode ri31 is exposed on the side surface. Each internal electrode plate 3
Tighten silver paste) 32, 32' fI8 so that it contacts the end surface of 1. Steel paste 32F! The silver paste 32' is in contact with the internal electrode plates 31 on one side of the laminate at intervals), and the silver paste 32' is baked and deposited on the other side of the laminate. The internal electrode plate Km is not touched.

Connect the lead wire to the silver paste (silver paste) 32 by soldering, etc. and connect it to the external terminal.
The wires (32 and 32') connected by the lead wire and connected to the external terminal BK are not necessarily printed on different sides of the laminate, but are printed in alternating positions on one side. There is no problem.

In addition, if a metal film of a small area is formed by contacting the silver paste 04) with gold or gold by vapor deposition on the first surface of each internal electrode plate, it can be used for thermocompression bonding used in ICs, etc. Lead wires can be connected using sonic crimping, etc., dramatically increasing production efficiency.

As described above, in the present invention, since the internal electrode plate is formed on the entire surface of the element, there is no ridge that causes stress concentration at the boundary portion, and large strain can be generated at a low voltage. Since a small metal film is formed in contact with the exposed end surface of each internal electrode plate exposed on the side surface, it is easier to solder the scissor metal NK lead wire, and it is easier to solder the scissor metal NK lead wire. internal electrode plates can be easily interconnected. That is, this has the effect of facilitating the manufacture of an electrostrictive element that can obtain a large strain effect with a low voltage.

[Brief explanation of the drawings] Fig. 1 is a cross-sectional view and a plan view showing an example of a conventional multilayer chip capacitor type electrostrictive effect element, and Fig. 2 is a nine-layer type electrostrictive element with an internal electrode plate formed on the entire surface of each element. FIG. 3 is a cross-sectional view and a plan view showing an electrostrictive effect element, and a perspective view showing an embodiment of the present invention. In the figure, 1-・film of electrostrictive material (or thin plate 2.2
′・-・Internal electrode plate, 3, 3′・・External electrode, 31・
・・Internal electrode plate, 32, 32′・・・Silver paste, M, B−・・External terminal. Back 1 Figure 1 Mei 2 Figure 2 (Two third factors

Claims (1)

[Claims] An internal electrode plate is formed over the entire surface of the film, and a plurality of thin plates are stacked on each other, and the internal electrode plate is formed on the side surface of the laminate where the end face of the internal electrode plate is exposed. 9. An electrostrictive effect element characterized in that a metal film of a small area is formed so as to touch each of the plates, and the internal electrode plates are electrically connected every other layer by lead connections of the wrinkled metal film.