JPS6230772Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Field of the Invention> This invention relates to a relay, particularly a relay that uses a piezoelectric element as a drive source for its contacts.

<Conventional technology and its problems> In recent years, with the aim of reducing power consumption,
Relays that use piezoelectric elements (bimorph) as the drive source for the contacts have been proposed for the purpose of reducing noise.

In the conventional method, both ends of the piezoelectric element are fixed, that is, supported in a state where they are supported at both ends, and the movable contact is brought into contact with and separated from the fixed contact by pressing the movable contact piece with a presser attached to the piezoelectric element. There is something I did.

According to this configuration, since the piezoelectric element is supported on both sides, it is possible to press and displace the movable contact piece with a larger torque than when the piezoelectric element is supported on one side.
Since the amount of displacement of the piezoelectric element itself is small, there is a drawback that a large pressing stroke cannot be achieved.

<Purpose of the invention> The purpose of this invention is to provide a relay that can exhibit stable contact switching characteristics even if the displacement force and amount of displacement of the piezoelectric element are small.

<Structure and Effects of the Invention> This invention consists of a piezoelectric element supported on both sides, a movable contact element that snaps into action with a compression spring, and an actuation piece that magnifies the displacement of the piezoelectric element and transmits it to the movable contact piece. It is characterized by being composed of a combination of.

With this configuration, it goes without saying that a coil-less relay can be easily achieved, and since the piezoelectric element is supported on both sides, it has high impact resistance, and it also has a strong pressing torque when combined with a specific actuating piece. , the snap action of the movable contact piece can be stably driven, and in other words, the operating characteristics can be improved.

<Description of Embodiment> An embodiment of this invention will be described below with reference to the drawings.

1 to 3, 10 is a piezoelectric element (bimorph), and this piezoelectric element 10 is housed in a case to be described later, and electrically includes a discharge resistor 11, an inrush current limiting resistor 12, and a switch 1.
It is connected to the power supply 13 via 4. This piezoelectric element 10 is supported at both ends by protrusions 16, 16 formed on the inner wall of the case 15, and can be bent downward using the protrusions 16, 16 as a fulcrum when a voltage is applied.

17 is a contact mechanism, and this contact mechanism 17 is equipped with a well-known snap action mechanism, and includes a movable contact piece 19 having a movable contact 18 at its tip, a common fixed terminal 20, and a movable contact piece 19 integrally attached to the movable contact piece 19. Compression spring 2 that is cut and formed to form a compression spring part
1. Fixed terminals 22, 23 and each fixed terminal 22,
It consists of fixed contacts 24, 25, etc. fixed to 23, respectively. By fixing the base end of the movable contact 19 to the common fixed terminal 20 and hinge-supporting the tip 21a of the compression spring 21 to the end of the common fixed terminal 20, the movable contact piece 19 is held in a tensioned state. ing.

Reference numeral 26 denotes an actuating piece interposed between the piezoelectric element 10 and the contact mechanism 17, and the actuating piece 26 is attached so that its base end can rotate about a pivot point 27 with respect to the common fixed terminal 20. and the free end 2
6a is in contact with substantially the center of the piezoelectric element 10. Furthermore, the pressing body 2 near the fulcrum of this actuating piece 26
8 is brought into contact with the movable contact piece 19, so that the force of the piezoelectric element 10 is magnified and transmitted to the movable contact piece 19 via the actuating piece 26.

In the above configuration, when no voltage is applied to the piezoelectric element 10, the piezoelectric element 10 extends horizontally as shown in FIG. The movable contact 18 opens the fixed contact 25 and closes the other fixed contact 24. Power supply 1
When a constant voltage is applied from the piezoelectric element 10
curves downward with the protrusions 16, 16 as fulcrums.
As a result, the operation piece 26 rotates clockwise about the fulcrum 27, and the movable contact piece 19 is rotated by the protrusion 28.
When it is pressed and crosses the dead line, the spring force of the compression spring 21 acts in the opposite direction, causing the movable contact 18 to open with respect to the fixed contact 24 and to close the fixed contact 25.

On the other hand, when the voltage application is cut off, the charges in the piezoelectric element 10 are discharged via the discharge resistor 11, and the piezoelectric element 1
0 returns due to its own elasticity, and the movable contact 18 switches to the fixed contact 24.

In this embodiment, the pressing body 2 of the actuating piece 26
8 presses the vicinity of the fixed end of the movable contact piece 19, so the amount of displacement of the piezoelectric element 10 is small, and if it opens and closes a current of 5A,
A displacement of approximately 50 μm is sufficient. A pressing force of about 50 g is required by the shifting actuation piece 26, and this displacement force may be obtained by stacking the piezoelectric elements 10, but by adjusting the lever ratio of the actuation piece 26, the force of the piezoelectric element 10 can be increased. can be expanded sufficiently.

Figures 4a and 4b show another embodiment in which the base end of the movable contact piece 19 is fixed to a support shaft 29, and this support shaft 29 is rotatably connected to the common fixed terminal 20. The configuration is similar to that shown in FIG. In this way, by making the base end of the movable contact piece 19 rotatable, smooth reversal operation can be obtained even if the displacement force or amount of displacement of the piezoelectric element 10 is small.

Note that the contact mechanism 7 may have other configurations as long as the movable contact piece 19 has a snap action.

[Brief explanation of drawings]

Fig. 1 is a front view showing one embodiment of the relay according to this invention, Fig. 2 is a front view of the relay in operation, Fig. 3 is a drive circuit diagram, and Figs. 4a and 4b are diagrams of other embodiments. FIG. 2 is a plan view and a front view showing main parts, respectively. 10... Piezoelectric element, 15... Case, 17...
Contact mechanism, 19... Movable contact piece, 21... Compression spring, 26... Operating piece, 28... Pressing body.

Claims (1)

[Scope of utility model registration request] a piezoelectric element whose both ends are supported relative to the case;
A contact mechanism includes a movable contact piece disposed inside the case and a compression spring that provides a snap action function to the movable contact piece, one end of which is supported by the case side, and the other end of which is connected to the piezoelectric element. An actuating piece is provided between an actuating piece that abuts on a substantially central portion, and an actuating piece is provided between both ends of the actuating piece and drives the movable contact piece when the actuating piece abuts the movable contact piece and detects deformation of the piezoelectric element. A relay equipped with a pressing body.