JPS6230777Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a small power-saving relay that utilizes piezoelectric phenomena.

When an electric field is applied to crystals such as barium titanate or lead zirconate titanate from a certain direction, distortion occurs in a fixed direction, which is known as the so-called reverse piezoelectric phenomenon. The purpose of this invention is to provide a relay with a simple structure that takes advantage of the fact that it consumes almost no power.

FIG. 1 shows an embodiment of the present invention, in which one end of each of two contact springs 1 and 2 is inserted and fixed into an insulator base 3 and protrudes substantially parallel to the same direction. Both ends of the electrostrictive element 4 in the strain direction are attached to opposing surfaces of both contact springs 1 and 2 via insulators 5, and both sides of the electrostrictive element 4, that is, both end faces in the thin direction, An electrode 6 made of a conductive thin plate is fixed. Each electrode 6 is connected by a thin lead wire 7 to an input terminal 8 which is inserted through and fixed to the insulator base 3. A portion of each contact spring 1, 2 protruding from the back side of the insulator base 3 also serves as an output terminal 9. Further, the tip A of one contact spring 2 is bent as shown in the figure and is close to the tip of the other contact spring 1, and contacts 10 and 11 are arranged at the tips of both contact springs 1 and 2, respectively, facing each other. It is provided.

In the example shown in Figure 1, there is a DC power supply 12 and a changeover switch 1.
3, a voltage of opposite polarity is applied to both electrodes 6, and the expansion and contraction of the electrostrictive element 4 at this time drives the intermediate portions of both contact springs 1 and 2 in mutually opposite directions. As a result, both contacts 10 and 11 are opened and closed.

FIG. 2 shows an example of the dimensions of the electrostrictive element 4.
The diameter is 20mm, the thickness is 0.3mm, and l:L= in Figure 1.
If the ratio is 1:4, applying a voltage of ±25V will cause expansion and contraction in the diameter direction and thickness direction, and a displacement of about 40μ will be obtained at the tip of the contact spring, which is normally required for small signals over 20μ. Therefore, it can be put to practical use.

FIG. 3 shows another example of the control circuit. In this case, since the electrostrictive element 4 has a capacity of about 50,000 PF, it is necessary to connect the discharge resistor 14 in parallel. If this resistance value is 200KΩ, the time constant is approximately 10mS, and the power consumption is almost negligible.

The present invention is constructed as described above, and since both ends of the electrostrictive element in the strain direction are fixed to the midpoints of the two contact springs, almost no voltage can be applied to the electrostrictive element. Contacts can be opened and closed without consuming power, and at this time, appropriate contact pressure can be obtained by contraction of the electrostrictive element.
The structure is extremely simple, and there is no need for a contact drive card or a movable iron hinge mechanism as with conventional electromagnetic relays, and the advantage is that an extremely durable, power-saving relay can be obtained.

[Brief explanation of drawings]

FIG. 1 is a schematic side view showing an embodiment of the present invention;
FIG. 2 is a front view of the main parts same as above, and FIG. 3 is a schematic side view showing another embodiment. 1, 2... Contact spring, 3... Insulator stand, 4...
Electrostrictive element, 5... Insulator, 6... Electrode, 7... Lead wire, 8... Input terminal, 9... Output terminal, 1
0,11...Contact.

Claims (1)

[Scope of utility model registration request] Both ends of the electrostrictive element in the strain direction are attached to opposing surfaces of two contact springs that are supported at one end and are arranged approximately parallel to each other, and direct current is applied to electrodes provided on both sides of the electrostrictive element. A relay configured to apply a voltage and drive both contact springs in opposite directions by expanding and contracting an electrostrictive element, thereby opening and closing the contacts provided at each tip of both contact springs.