JPS625526A - Piezo-electric relay - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a piezoelectric relay, and particularly to a piezoelectric relay using laminated piezoelectric elements.

[Prior Art] Fig. 2 shows a schematic structure of an example of a conventional piezoelectric relay. 3, and the other ends of each of the bimorph piezoelectric element 2 and the snap drive spring 3 are fixed to a fixed support member 4. The fixed support member 4 has a fixed contact b
1 and b2 are provided, and the movable contacts a1 and a2 of the movable contact portion 1 are arranged so as to correspond to each other between the two fixed contacts b1 and b2.

When a voltage is applied to the bimorph piezoelectric element 2, the bimorph piezoelectric element 2 is displaced, for example, in the direction of the fixed contact b1, and moves the movable contact portion 1 in the same direction. This movement of the movable contact portion 1 causes the snap drive spring 3 to perform a snap action, and the movable contact al and the fixed contact b1 close, and the movable contact a2 and the fixed contact b2
and opens. If a voltage of opposite polarity is applied to the bimorph piezoelectric element 2, a snap action in the opposite direction will occur, and the movable contact a
1 and fixed contact b1 are opened, and movable contact a2 and fixed contact b2 are closed. That is, the /'immorph type piezoelectric element 2 is used as an actuator for causing a snap action.

This piezoelectric relay has features such as extremely low power consumption compared to electromagnetic solenoid type relays, no heat generation or electromagnetic noise, high response speed, and easy manufacturing and integration. ing.

[Problems to be Solved by the Invention] However, the conventional piezoelectric relay described above had the following problems.

A piezoelectric relay using a bimorph type piezoelectric element shown in FIG. 2 is significantly inferior to a piezoelectric relay using a laminated piezoelectric element in terms of response speed and energy conversion efficiency.

Furthermore, in order to operate the piezoelectric relay, it is necessary to separately provide means for switching the voltage applied to the piezoelectric element. That is, in a piezoelectric relay using a bimorph piezoelectric element, a means for switching the polarity of the applied voltage is required in order to switch the displacement direction of the bimorph piezoelectric element 2 and cause a snap action of the movable contact portion l.

As described above, since the conventional piezoelectric relay requires a switching means, it also has the problem that the relay driving method and driving device become complicated.

[Means for Solving the Problems] A piezoelectric relay according to the present invention has a movable contact portion disposed between fixed contact portions having a contact on at least one side, and the movable contact portion is snap operated using a piezoelectric element. , a piezoelectric relay that opens and closes a contact, characterized in that a laminated piezoelectric element is provided in the movable contact part, and the movable contact part is caused to perform a snap operation by expanding the laminated piezoelectric element.

[Function] With this configuration, the structure is simplified because it is only necessary to provide one laminated piezoelectric element as an actuator in one movable contact part, and the response is higher than that of a piezoelectric relay using a bimorph piezoelectric element. Speed can be increased significantly.

Furthermore, since the snap action can be caused only by the repulsive action generated by stretching one laminated piezoelectric element, it can be driven extremely easily without the need for conventional switching means.

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

FIG. 1 is a schematic diagram of an embodiment of a piezoelectric relay according to the present invention.

In the figure, the movable contact part 11 is connected to a laminated piezoelectric element 12 and a displacement direction of this laminated piezoelectric element 12 (in the direction of the arrow in the figure).
It consists of movable contacts a1 and a2 provided at both ends.

Movable contact portion 11 in the direction perpendicular to the arrow direction in the figure
is supported by a snap drive spring 13 and a spring 14, and the other end of each of the snap drive spring 13 and spring 14 is fixed to a fixed support member 15. The fixed support member 15 is provided with fixed contacts b1 and b2, and the movable contacts a1 and a2 of the movable contact portion 11 are arranged between both rotating contacts b1 and b2 so as to correspond to each other.

Next, the operation of this embodiment having such a configuration will be explained.

The states of the contacts are assumed to be in a first state where contacts a1 and bl are closed and contacts a2 and b2 are open, as shown in the figure.

When a voltage is applied to the laminated piezoelectric element 12 in this state, since the contacts a1 and bl are closed, the laminated piezoelectric element 12
extends toward the fixed contact b2 side. Since the elongation of the laminated piezoelectric element 12 occurs in an extremely short time of less than O,1m5ec,
The laminated piezoelectric element 12 itself causes a rapid repulsive movement via the fixed contact b1. As a result, the snap drive spring 13 and the spring 14 are also deflected toward the fixed contact b2, causing the snap drive spring 13 to perform a snap action. As a result, the movable contact portion 11 rapidly moves toward the fixed contact b2, and the contact state changes from the first state to the state where the movable contact a2 and the fixed contact b2 are closed.
The state shifts to a second state in which the movable contact a1 and the fixed contact b1 are open. At this time, the movable contact a2 and the fixed contact b2 are closed with sufficient contact force due to the bias of the snap drive spring 13, so there is no need to continue applying voltage to the laminated piezoelectric element 12.

In this second state, when a voltage is applied to the laminated piezoelectric element 12, since the contacts a2 and b2 are closed this time,
The laminated piezoelectric element 12 extends toward the fixed contact bl. As described above, the snap drive spring 13 causes a snap action due to the rapid repulsion at this time, and the movable contact portion 11 rapidly moves toward the fixed contact bl. Therefore, the contact state returns from the second state to the first state in which the movable contact a2 and the fixed contact b2 are open and the movable contact a1 and the fixed contact b1 are closed. Similarly, each time a voltage is applied to the laminated piezoelectric element 12, the contact state of this embodiment alternates between the first state and the second state.

As already mentioned, when this embodiment is in the second or second state, it is not necessary to continue applying voltage to the laminated piezoelectric element 12, and it is sufficient to apply voltage only when changing the state.

In this embodiment, the snap drive spring 13 is used to snap the movable contact portion 11, but the present invention is not limited to this, and for example, a snap drive means using a permanent magnet or the like may be used. That is clear.

[Effects of the Invention] As described above in detail, the piezoelectric relay according to the present invention includes a laminated piezoelectric element provided in the movable contact portion, and in order to snap the movable contact portion by expanding the laminated piezoelectric element. It has a simple structure in which only one laminated piezoelectric element is provided as an actuator in one movable contact part, and the response speed can be significantly increased compared to a piezoelectric relay using a bimorph type piezoelectric element.

Furthermore, since the movable contact portion can be snap-operated by simply extending one laminated piezoelectric element to open and close the contact, there is no need for conventional switching means, and the drive method and drive device can be is extremely simplified.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of an embodiment of a piezoelectric relay according to the present invention, and FIG. 2 is a schematic diagram of an example of a conventional piezoelectric relay. 1.11・φ・Movable contact part 2...Bimorph type piezoelectric element 3.13...Snap drive spring 4.15...Fixed support member al, al...Movable contact bl, b2@...Fixed contact

Claims (1)

[Claims] (1) A piezoelectric relay in which a movable contact part is disposed between fixed contact parts having a contact point on at least one side, and the movable contact part is snap operated using a piezoelectric element to open and close the contact, the movable contact part A piezoelectric relay, characterized in that a laminated piezoelectric element is provided in the piezoelectric relay, and the movable contact portion is caused to snap action by extending the laminated piezoelectric element.