JPS6230776Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a low power consumption relay that uses a bimorph as a driving source instead of an electromagnet.

Various relays using bimorphs have been proposed in the past, but all of them have been impractical because the amount of displacement of the bimorphs is small. Bimorph is made by bonding two types of thin plates made of piezoelectric material, and because it bends when voltage is applied, it is seen as promising as a small relay that does not require an electromagnet.However, the driving force is small and the amount of displacement is small. Since it is small, it is difficult to obtain sufficient contact pressure and contact working distance, and it has not yet been put into practical use.

The present invention has been developed in view of the above points, and it is possible to achieve a sufficient snapping action by interposing a snap spring between the tips of two bimorphs and differentially displacing both bimorphs. The purpose is to obtain contact pressure and fast-acting characteristics.

Embodiments of the present invention will be described below based on the drawings. In the embodiment shown in FIG. 1, two bimorphs 1 and 2 are arranged in substantially the same plane with their free ends close to each other. Each bimorph 1, 2 is made by laminating two pieces of piezoelectric material with an electrode plate fixed to the surface, and has supporting members 3, 4 made of an insulating material at the tip.
A snap spring 5 made of a C-shaped leaf spring is interposed between the tips of the support members 3 and 4.
Each of the bimorphs 1 and 2 is connected to a control power source by a lead wire 7, so that when a control voltage is applied, the bimorphs 1 and 2 are displaced in opposite directions. Further, a movable contact 8 is caulked and fixed to the support member 4 of at least one of the bimorphs 2 so as to face the fixed contacts 9 and 10. The movable contact 8 is connected to the load circuit by a lead wire (not shown), and the crimp terminal plate of the lead wire is caulked and fixed to the eyelet hole of the support member 4 together with the movable contact 8. 11,1
2 is a stopper.

FIG. 1a shows a state in which no control voltage is applied, and both bimorphs 1 and 2 are pressed against the stopper 11 and the fixed contact 10 by the elastic force of the snap spring 5, respectively. When a control voltage is applied, forces in opposite directions (arrow A) are applied to both bimorphs 1 and 2, and the snap spring 5 is gradually compressed, and when the state shown in FIG.
2 is snapped and reversed, and the resilient force of the snap spring 5 brings the movable contact 8 into pressure contact with the fixed contact 9 as shown in FIG. In this embodiment, fixed contacts 9, 1
0 and the distance between the stoppers 11 and 12, bimorph 2 is set to be displaced more than bimorph 1, and therefore bimorph 2 is displaced by bimorph 1 against its own bending force. The movable contact 8 is pushed back and the snap spring 5
As shown in figure b, the contact does not separate from the fixed contact until it reaches the dead center, and the contact opens instantaneously by the snap action, resulting in fast-acting characteristics.

Further, even when both bimorphs have the same stroke as shown in FIG. 2, if the spring constant of one bimorph 2 is set small, the other bimorph 2 can obtain fast acting characteristics. Furthermore, the embodiment shown in FIG. 3 achieves miniaturization by arranging both bimorphs 1 and 2 in parallel, facing in the same direction. Further, in FIG. 4, one of the support members 3 is extended into an L-shape and the snap spring 5 is arranged on the extension line of the bimorph 2. With this configuration, torsional force is applied to both bimorphs 1 and 2. This prevents them from joining.

The present invention is constructed as described above, and by using two bimorphs and a snap spring interposed between their tips, it is possible to obtain large contact pressure and sufficient contact operating distance, and also improve fast-acting performance. This has the advantage that a small, power-saving bimorph type relay, which has conventionally been difficult to put into practical use due to its small driving force, can be realized with an extremely simple configuration.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view showing one embodiment of the present invention, and a, b, and c show the operating states thereof. FIG. 2 is a schematic side view showing another embodiment same as the above, FIG. 3 is a schematic side view showing still another embodiment, where a is a top view, b is a front view, and FIG. 4 is a schematic side view showing still another embodiment. It is a perspective view showing an example. 1 and 2 are bimorphs, 3 and 4 are support members, 5 is a snap spring, 7 is a lead wire, 8 is a movable contact,
9 and 10 are fixed contacts, and 11 and 12 are stoppers.

Claims (1)

[Scope of utility model registration request] Two bimorphs are disposed in substantially the same plane with their free ends connected to each other with snap springs, and both bimorphs are displaced in opposite directions by application of a control voltage, so that at least one bimorph A bimorph type relay that drives the contacts to open and close.