JPH0265185A - Manufacture of circular piezoelectric vibrator - Google Patents

Abstract

PURPOSE:To reduce cracks to be generated and unpolarized parts at the time of polarization and to simplify a jig by commonly grounding ring electrodes at the time of the polarization, and electrically connecting one positions of positive and negative split electrodes. CONSTITUTION:A plurality of split electrodes formed on one side face of a piezoelectric ceramic disc 1 are formed in a ring state, and connectors 2, 3 for connecting the electrodes at the outside and inside of electrode row at the time of forming of the split electrodes. On the other hand, a ringlike electrode 6 is so formed on the other side face of the disc 1 as to oppose to the split electrodes. The electrode 6 is connected to a ground terminal, and positive split electrodes 4 and negative split electrodes 5 are respectively connected to the electrodes 2, 3 as positive and negative terminals, positive and negative DC high voltages are applied to simultaneously polarize the positive and negative split electrodes. After the polarization, the outside and inside of the split electrodes are so removed as to remove the electrodes 2, 3 thereby to obtain a ringlike piezoelectric vibrator 7.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Object of the Invention [Field of Industrial Application] The present invention relates to the formation of electrodes for annular piezoelectric vibrators used in ultrasonic motors and the like.

[Conventional technology]

The electrode configuration of this type of piezoelectric vibrator is as shown in FIG.
In the conventional method of polarization, electrical connections with each divided electrode are made using a contact bottle, etc., resulting in poor contact of the terminals, uneven pressure on the terminals, etc., resulting in the occurrence of unpolarized parts and cracks during polarization. However, there were some drawbacks, such as the need for a complicated polarization jig.

[Problem to be solved by the invention]

In order to eliminate these drawbacks, the present invention forms the divided electrodes on a disk-shaped or annular piezoelectric ceramic plate, and at the same time provides connection electrodes for connecting the divided electrodes of the same polarity, and then connects the connection electrodes. After polarization, the piezoelectric vibrator is processed into a ring shape, or by removing the connecting electrode part by etching, etc., to form an annular piezoelectric vibrator, reducing defects such as cracks and unpolarization, and simplifying the construction of jigs and tools. This is what we are trying to do.

Below is a margin 9 Structure of the invention [Means for solving the problem] According to the present invention, in manufacturing a toroidal vibrator having electrodes of different polarities on at least one surface of a toroidal piezoelectric ceramic disc, the the outside of the electrode during formation of the electrode,
and a method characterized in that a connecting electrode for connecting electrodes of the same polarity to each other is formed inside, and after performing polarization treatment using the connecting electrode, the connecting electrode part is removed. Obtain a toroidal oscillator.

[Effect]

In the polarization work of annular piezoelectric ceramic plates used in ultrasonic motors, etc., connecting electrodes are placed among the divided electrode rows to connect the same polarities of the divided electrodes used specifically for forming the motor.
By performing polarization through this connecting electrode provided on the outside, uniform polarization can be achieved in one operation, and a piezoelectric vibrator of stable quality can be obtained.

〔Example〕

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

FIG. 1 shows an example of a divided electrode and a connection electrode pattern according to the present invention, in which a plurality of divided electrodes 4.5 are formed in a ring shape on one surface of a piezoelectric ceramic disk 1, and these When forming the divided electrodes, connecting electrodes 2.3 are formed on the outside and inside of these electrode rows, respectively, for connecting the same polarity to each other. A ring electrode 6 is formed on the other surface of the one-pressure type ceramic disc 1 so as to face the ring-shaped divided electrode. In FIG. 1, the ring electrode 6
is used as the ground terminal, and the divided electrodes 4 and 5 connected by the connecting electrodes 2.3 are used as child terminals and terminals, respectively. By applying a voltage, polarization processing corresponding to each of the negative and negative divided electrodes is performed at once. The ring-shaped piezoelectric vibrator 7 shown in FIG. 2 is obtained by removing the outer and inner parts of the divided electrodes by ultrasonic processing or the like, just as the connecting electrodes 2.3 are removed after the polarization process. That is, FIG. 2(a) shows what is shown in FIG. 1(a) with the inside and outside of the chain line removed.

The above explanation has been made using a disc-shaped piezoelectric ceramic material, but a similar electrode is formed on a circular piezoelectric ceramic plate, and after polarization, a connecting electrode 2.
3 may be removed.

According to the present invention, during polarization, the ring electrode 6 is used as a common ground, and the polarization process is made possible by electrically connecting one point each of the - and - divided electrodes. There will be none. Furthermore, since the number of contact bottles of the polarization jig is small, cracking during polarization can be prevented, and the polarization jig can also be simplified.

Effects of the Invention [Effects of the Invention] As shown above, according to the present invention, it is possible to reduce cracks, unpolarization, etc. that occur during polarization, and to simplify jigs and tools, which is economical and stable in quality. It is possible to provide a device with

Margin below

[Brief explanation of the drawing]

FIG. 1 is an embodiment of the present invention, showing an electrode pattern printed on a disc-shaped piezoelectric ceramic disc, in which (a) shows a pattern of divided electrodes in a top view, (b) shows a front view, and (c)
) is a ring-shaped electrode in the bottom view. Figure 2 shows an example of a ring-shaped piezoelectric vibrator and its polarization pattern used in the ultrasonic motor element of the present invention, (a)
is a top view, (b) is a front view, and (c) is a bottom view. 1...Piezoelectric ceramic disk. 2... Connection electrode (positive side). 3... Connection electrode (minus side). 4...Divided electrode (positive electrode). 5... Split electrode (negative pole). 6...Ring electrode. 7...Piezoelectric vibrator.

Claims (1)

[Claims] 1. In an annular piezoelectric vibrator having electrodes of different polarities on at least one surface of an annular piezoelectric ceramic disk, for connecting electrodes of the same polarity on the outside and inside of the electrode when forming the electrode. 1. A method of manufacturing an annular piezoelectric vibrator, comprising: providing a connecting electrode; and removing the connecting electrode portion after performing a polarization process using the connecting electrode.