JPH01112629A - Piezo relay - Google Patents

Abstract

PURPOSE:To simplify the construction and ensure opening and closing operation of contacts by making contact opening/closing action by the use of two resilient members, which deform in accordance with deformation of a piezo element and have a potential enlarging mechanism. CONSTITUTION:Rigid members 2, 3 are fixed to the ends of a piezo element 1, and the distance between them varies when a voltage is impressed on the piezo element 1. Resilient members 6, 7 are fixed between these rigid members 2, 3. These resilient members 6, 7 have bends a, b and diverging arms 6a, 7a in the middle of the longitudinal direction, and the tips c, c of the diverging arms are contacted or separated according to displacement of the rigid members 2, 3 through the action of lever to provide contact opening/closing action. Because this construction is simple and free from friction in actions, there is little wear and sure contact action an be expected.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a piezoelectric relay driven using a piezoelectric element.

[Background Art] It is known that if a relay is constructed using a piezoelectric element, it can be made to have characteristics such as power saving, low heat generation, and resistance to electromagnetic noise.

If a laminated piezoelectric element is used, the above-mentioned performance can be sufficiently exhibited, but it is necessary to increase the driving distance by several times to several tens of times the magnification mechanism, and various magnification mechanisms have been proposed.

However, since all of the conventional enlargement mechanisms include a portion that comes into frictional contact with the hinge portion, there are problems in that they have short lifespans due to wear, and have complicated structures and poor manufacturability.

[Purpose of the invention]

An object of the invention is to provide a piezoelectric relay that is simple in structure and does not cause wear.

(Disclosure of the Invention) The piezoelectric relay of the present invention uses a laminated piezoelectric element, and a mechanism for expanding the displacement thereof is constructed of an elastic body having a bent portion and a branch arm.One contact point is connected to the branch arm. Provided at the tip.

According to the configuration of the present invention, the elastic body is deformed so that the angle of the bent portion changes as the laminated piezoelectric element expands and contracts, and the angle of the branch arm changes. Therefore, the expansion and contraction of the laminated piezoelectric element is expanded, the tip of the branch arm is largely displaced, and the contact is opened and closed.゛The elastic body is like a pin support I) 21L? Since there are no parts, there is no wear.

Emperor ■ A first embodiment of this invention will be explained based on FIGS. 1 to 3. In the figure, l is a laminated piezoelectric element, and rigid bodies 2 and 3 are fixed to both ends of the piezoelectric element in the expansion and contraction direction so as to protrude from both sides. The rigid body 2.3 is a ceramic or a metal plate partially made of ceramic or glass for boat fishing. A pair of enlarging mechanisms 4 are provided between these rigid bodies 2 and 3 on both sides of the laminated piezoelectric element 1. The enlarging mechanism 4 and the laminated piezoelectric element 1 are housed in a case 5, and fixed by placing the lower rigid body 2 on a thick platform 5a of the bottom plate of the case 5.

As shown in FIG. 2, the laminated piezoelectric element 1 has a power supply line 12 made of FQ copper wire.

The enlarging mechanism 4 consists of a pair of bent rod-shaped elastic bodies 6.7 whose both ends are fixed to the upper and lower rigid bodies 2.3. These elastic bodies6.
7 is bent in a two-shape shape at bent portions a and b, and the portion between bent portions a and b extends to one side to form branch arms 6a and 7.
A is integrally provided. Branch arm 6 of both elastic bodies 6.7
A pair of contacts 8 and 9 are provided at the tips of a and 7a, and these contacts 8 and 9 are vertically opposed to each other with a predetermined gap in between. The elastic body 6.7 also serves as a conductor for the contacts 8 and 9,
It is connected to the terminal 10 of the case 5 with a braided copper wire 11.
As shown in FIG. 3, the elastic body 6.7 has cutout grooves 13.14 formed in the bent portions a and b.

Explain the operation. When a DC voltage is applied to the laminated piezoelectric element 1, it expands toward the free end located at the upper side of the figure. At this time,
The upper end of the elastic body 6.7 of the expanding mechanism 4 is pulled, the branch arms 6a, 7a are tilted, and the contact point 8.9 is moved. Contact 8
．． The movement IY of 9 is as follows, where y is the movement amount of point b. A branch arm 6a of a pair of elastic bodies 6 and 7.

Since 7a deforms differentially, contact 8.9 closes with a movement amount of 2 (9) of Y. When the voltage is removed, laminated piezoelectric element 1 contracts, moves by the same amount, and contacts 8. °9 opens.

In this way, the contacts 8.9 are opened and closed by the elastic deformation of the elastic bodies 6.7, but since the elastic bodies 6, 7 do not have frictional parts such as pin supports, no wear occurs. Therefore, it has a long life. Since the displacement is expanded by the integrated elastic body 6.7, the structure is simple.

In addition, since elastic bodies 6.7 are provided on both sides of the laminated piezoelectric element 1 and are pulled through the rigid bodies 2.3,
The load is applied evenly and can be pulled in parallel, resulting in stable operation. Moreover, since the magnification rate is doubled by differentially using two similar elastic bodies 6.7 with a simple structure,
The magnification rate of errors is small, and manufacturing as parts is easy.

Note that a plurality of sets of contacts may be equally provided on both sides of the laminated piezoelectric element 1.

FIGS. 4 to 8 each show other embodiments.

In the example shown in FIG. 4, the enlarging mechanism 4' is constructed only by a pair of elastic bodies 6.7 provided with the laminated piezoelectric element 1 sandwiched therebetween.

Other structural effects are the same as in the first embodiment.

FIG. 5 shows a branch arm 6a bent into elastic bodies 6' and 7'.
', 7a' are provided. In this example, if the amount of movement of point a is y, then the amount of movement Y of point d is as follows.

In the examples shown in FIGS. 6 to 8, one of the contacts 6 is provided on fixed contact rods 20 to 22. 6°′ is an elastic body,
6a'' is its branch arm.

In the example shown in FIG. 8, the image is expanded into two stages using the lever principle. In this example, for the movement amount y of point b, the movement amount Y of one point
becomes .

〔Effect of the invention〕

The piezoelectric relay of the present invention uses a laminated piezoelectric element, and the mechanism for expanding its displacement is constituted by an elastic body having a bending part and a branch arm 1, so that the elastic body bends due to expansion and contraction of the laminated piezoelectric element. It deforms so that the angle of the branch arm changes, and the angle of the branch arm changes.

Therefore, the expansion and contraction of the laminated piezoelectric element is expanded, the tip of the branch arm is largely displaced, and the contact is opened and closed.・Since the elastic body does not have a frictional part like a pin support, no wear occurs. Therefore, it has a long life. Furthermore, since the displacement is expanded by an integrated elastic body, the structure is simple.

[Brief explanation of the drawing]

The first is a cutaway front view of the first embodiment of the present invention, FIG. 2 is a perspective view of the laminated piezoelectric element, FIG. 3 is an enlarged front view of the elastic body, and FIGS. 4 to 8 are FIG. 7 is a cutaway front view of each other embodiment. DESCRIPTION OF SYMBOLS 1... Laminated piezoelectric element, 2.3... Rigid body, 4... Enlargement mechanism, 6, 7... Elastic body, 6a, 7a... Branch arm, 8.9... Contact, a , b...Bending part 4 Fig. 1 Fig. 51...Laminated piezoelectric element 2.3...Rigid body 4...Enlargement mechanism 6.7...Elastic body 86°
7a - Branch 7-1 98.9...
Contact point 46c! a, b...bent part [7a73177a \ -m- , □ 1□ 1/ Fig. 1\, / Fig. 3 Fig. 6 393 6a''/ Fig. 7

Claims (1)

[Claims] An elastic body is provided between both ends of a laminated piezoelectric element, and this elastic body has a bent part and a branch arm in the middle in the length direction, and as the both ends are displaced, the tip of the branch arm is displaced more than the above displacement. A piezoelectric relay in which one of the contacts that open and close mutually is provided at the tip of the branch arm.