JPS63122288A - Electrostriction effect element - Google Patents

Abstract

PURPOSE:To much improve reliability and mass production in an effect element, by connecting terminal electrode conductors with outer electrode conductors on their respective chamfered corner parts. CONSTITUTION:Terminal electrode conductors 35a and 35b are sticked/formed on surfaces of piezo-electric ceramic members 31 which are disposed on both ends of a laminate 30, and they are connected with extended parts of a pair of outer electrode conductors 34a and 34b on their chamfered corner parts 30a and 30b. When this electrostriction effect element is equipped with mounting members 50 and 51 made of thick plates of rigidity or the like on the upper and lower surfaces of the element and when a voltage is applied across the mounting members 50 and 51, the voltage is applied to inner electrode conductors 32 through the terminal electrode conductors 35a and 35b and the outer electrode conductors 34a and 34b. Therefore, lead wires for voltage application become needless, so that deterioration in reliability of connections caused by breakage of the lead wires or so can be removed.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention includes a laminated sintered body in which sheet-like piezoelectric ceramic members and internal electrode conductors are alternately laminated, and One end of the internal electrode conductors exposed on a pair of side surfaces is alternately insulated on the opposing side surfaces, and the other end of the internal electrode conductor that is not insulated is connected to an external electrode conductor provided for each side surface. This relates to the electrostrictive effect elements connected to each other.

[Prior Art] FIG. 4 is a sectional view of a conventional example of this type of electrostrictive effect element. In this electrostrictive effect element, an internal electrode 32 is formed on the surface of a piezoelectric ceramic member 31, a plurality of these pieces are stacked in a layer to form a laminate 30, and an end face of the internal electrode 32 exposed on one side thereof is An insulating film 33a is formed every other layer, and a first external electrode conductor 34a is further formed thereon.

On the other hand, on the other opposing side surface, an insulating film 33b is formed on the end face of the internal electrode 32 on which the above-mentioned insulating layer 33a is not formed, and a second external electrode conductor 34b is formed thereon.
The structure is such that lead wires 10a and 10b are connected to external electrode conductors 34a and 34b on both sides.

This conventional electrostrictive element is connected to an external electrode conductor 34 from external terminals A and B of a voltage supply section via lead wires 10a and 10b.
When a voltage is applied between a and 34b, a voltage is applied to both ends of all the piezoelectric ceramic members 31, and the entire element is distorted in the X and Y directions shown by the arrows.

[Problems to be Solved by the Invention] Since the conventional electrostrictive effect element described above has a structure with lead wires, the lead wires 10a, fob may be damaged by repeated voltage application, long-time application, high voltage application, etc. Alternatively, the connection points between the lead wires 10a, 10b and the external electrode conductors 34a, 34b may break, and if the lead wires 10a, 10b are connected by soldering, etc., the external electrode conductors 34a, 34b may break.
This method has major drawbacks in terms of reliability, such as cracking of the solder portions 4a and 34b, and destruction of the insulators 33a and 33b and the piezoelectric ceramic member 31 due to the strain suppressing effect of soldering.

[Means for Solving the Problems] The electrostrictive effect element of the present invention has a piezoelectric ceramic member at both ends of a laminated sintered body, which is diagonally diagonally connected to the side surface on which the external electrode conductor is provided. Two certain corners are chamfered, a pair of terminal electrode conductors are formed on the outer surface of the piezoelectric ceramic member at both ends, and the terminal electrode conductor and the external electrode conductor are respectively connected at the chamfered corners. It is characterized by being

The chamfered chip-type structure greatly improves the reliability and mass productivity of the electrostrictive element.

[Example] Next, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of the electrostrictive effect element of the present invention, and FIG. 2 is a perspective view of a corner thereof.

In this electrostrictive effect element, piezoelectric ceramic members 31 and internal electrode conductors 32 are stacked alternately as in the conventional case, and the internal electrode conductors 32 are provided on the end faces of the laminate 30 formed as a laminated sintered body and on opposite sides. The external electrode conductors 34a and 34b are connected alternately every other layer.
A pair of comb-shaped electrodes are configured.

The piezoelectric ceramic member 31 is made by, for example, adding a small amount of a softener binder to a prefired powder of an electrostrictive material whose main component is nickel/lead niobate Pb (Nil/3Nb2/3)03, and adding this to an organic solvent. A dispersed slurry was prepared, and this slurry was formed by a slip casting film formation method. The internal electrode conductor 32 is formed by applying a conductive paste whose main component is a mixture of silver powder and palladium powder at a ratio of 70:30 to one side of the piezoelectric ceramic member 31 by screen printing or the like. . The electrostrictive effect element is manufactured by laminating a predetermined number of piezoelectric ceramic members 31 such that the internal electrode conductors 32 form a pair, integrating them by hot pressing, and then sintering them at a temperature of about 20° C. for about 2 hours to form a piezoelectric ceramic member. 31 and internal electrode conductors 32 are alternately laminated, and the side surfaces are cut so that the end surfaces of the internal electrode conductors 32 are exposed to the outside to form a columnar carcass 30.

An insulator 33a such as glass is formed every other layer on the internal electrode conductor 32 exposed on the first side surface of the laminate 30, that is, the left side surface in FIG. A first external electrode conductor 34a is formed by depositing the first external electrode conductor 34a, and a first external electrode conductor 34a is formed on the internal electrode conductor 32 on which insulation is not formed on the first side surface on the side surface opposite to the first side surface.
is formed, and an external electrode conductor 34b is similarly formed thereon.

As shown in FIG. 2, the two diagonal corners of this laminate 30, namely the bottom corner 30a and the top corner 30b, are chamfered at approximately 45 degrees using a polishing machine or the like. .

Further, terminal electrode conductors 35a and 35b are formed on the surfaces of the piezoelectric ceramic members 31 at both ends of the laminate 30, respectively, and the extended portions of the pair of external electrode conductors 34a and 34b and the chamfered corner portions are formed. They are connected at 30a and 30b.

This electrostrictive effect element is made of a rigid thick plate or the like, and is mounted by attaching members 50.51 to the upper and lower surfaces of the electrostrictive effect element, and by applying a voltage between the members 50 and 51, the terminal electrode conductor 35a , 35b and external electrode conductors 34a, 34b
A voltage can be applied to the internal electrode conductor 32 via.

FIG. 3 is a perspective view showing another embodiment of corner chamfering. In this case, the lower corner 30a and the upper corner 30b of the laminate 30 are chamfered into a cylindrical shape using a polisher or the like, and the same effect as in the first embodiment can be obtained.

[Effects of the Invention] As explained above, the present invention chamfers the two diagonal corners of the upper and lower surfaces of the electrostrictive element, and provides terminal conductor electrodes on the upper and lower surfaces to connect them to external electrode conductors. By configuring the structure so that the applied voltage is applied to the internal electrode conductor through the terminal electrode conductor and the external electrode conductor, lead wires for voltage application are no longer required, eliminating deterioration in connection reliability due to lead wire breakage, etc. On the other hand, the chip-shaped structure has the effect of increasing mass productivity.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of one embodiment of the electrostrictive effect element of the present invention, FIGS. 2 and 3 are perspective views showing chamfered corners, and FIG. 4 is a sectional view of a conventional example. 30, Laminate, 30a, 30b, Corner 31, Piezoelectric ceramic member 32,
,,,internal electrode conductor, 33a, 33b,,,insulating film. 34a, 34b, ..., external electrode conductor, 35a, 35b, ..., terminal electrode conductor, 50.51. ,,,Installation is by parts. Figure 1 Figure 4

Claims (1)

[Claims] It includes a laminated sintered body in which sheet-like piezoelectric ceramic members and internal electrode conductors are alternately laminated, and one of the internal electrode conductors exposed on a pair of opposing side surfaces of the laminated sintered body. In the electrostrictive element, the ends of which are alternately insulated on the opposing side surfaces, and the other ends of the uninsulated internal electrode conductors are respectively connected to external electrode conductors provided for each of the side surfaces, Of the corners of the piezoelectric ceramic members at both ends of the laminated sintered body that are in contact with the side surfaces on which the external electrode conductors are provided, two diagonally located corners are chamfered, respectively, and the outer surfaces of the piezoelectric ceramic members at both ends are chamfered. An electrostrictive effect element, characterized in that a pair of terminal electrode conductors is formed and adhered to the outer electrode conductor, and the terminal electrode conductor and the external electrode conductor are connected to each other at chamfered corners.