JPH0310580Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to a switch that switches signals by utilizing the deflection of a movable spring and has a deformable drive force transmission rod (drive rod). be.

[Prior art]

(Part 1) FIG. 5a shows an embodiment of a conventionally used switch. This conventional switch has a structure in which a drive rod 3 (hereinafter referred to as a drive pin) linearly driven back and forth by an electromagnetic coil 5 presses a movable spring member 2 to perform a switch operation.
However, in this method, since the movable spring 2 and the tip of the drive pin 3 repeatedly collide and slide, abrasion powder is generated from that portion and adheres to the contact portion 2a, causing contact failure.

(Part 2) FIG. 6a shows an embodiment of a switch mechanism devised to solve the problem pointed out in the prior art (Part 1). That is, the movable spring 2 and the drive pin 3 that is linearly driven in a reciprocating manner are fixed to eliminate generation of abrasion powder from this portion.

However, on the other hand, compared to the prior art (Part 1), the (Part 2) has the following drawbacks.

(A) The amount of deviation (deflection) of the contact portion 2a at the tip of the movable spring 2 decreases, so that contact becomes impossible or the contact pressure decreases.

(b) The bending moment (bending stress) of the movable spring has increased, resulting in a shortened fatigue rupture life of the movable spring.

(c) Considering the distance a between the contacts as constant, the movable spring 2
In order to ensure the allowable bending stress and contact pressure, the switch mechanism becomes larger compared to the prior art (Part 1).

This will be explained based on Fig. 5a, Fig. 5b, Fig. 6a, and Fig. 6b. In the prior art (part 1), as shown in Fig. 5a, the movable spring is fixed at one end. On the other hand, in case (2), the state becomes as shown in FIG. 6a (two-point support state). The bending moment diagram at this time is (Part 1) in Figure 5b, (Part 2)
In the case of , the result is shown in FIG. 6b. If the material and shape and dimensions of the movable spring are the same, the maximum bending moment M1 of (Part 1) and the maximum bending moment of (Part 2)
M2 has a relationship of M1<M2. Therefore, in case (2), in order to reduce the maximum bending moment value M2 and lower the bending stress, it is necessary to increase the distance y between the fixed end of the movable spring and the drive pin. This increases the size of the device.
Also, in case (1), the movable spring has a deflection angle between the drive pin 3 and the contact part, but in case (2), it does not have a deflection angle, so assuming that the distance a between the contacts is constant, the drive It is necessary to lengthen the driving stroke of the pin. This means that the electromagnetic coil 5
It also has the disadvantage of requiring an extra energy supply.

[Problem that the invention attempts to solve]

In the case of the conventional example (part 1) shown in FIG. 5, abrasion powder generated near the contact portion is unfavorable in terms of contact reliability. Furthermore, compared to the method (Part 1), the method (Part 2) shown in FIG. 6 completely fixes the movable spring and the drive pin, so theoretically no abrasion powder is generated in this part. However, the conventional method (part 2) has the drawbacks shown in (a) to (c) above.

The purpose of the present invention is to secure the advantages of the method (Part 2) while improving the disadvantages.

[Means to solve the problem]

The gist of the present invention is a mechanism in which the drive pin has a deformable function and transmits drive while responding to the deformation of the movable spring.

[Function] According to the switch of the present invention, since the movable spring that is driven linearly in a reciprocating manner and the drive pin are fixed, no abrasion powder is generated from this fixed part, and therefore,
The surface condition of the contact portion 2a located nearby can be kept clean. Furthermore, since the drive pin has the function of being deformable, it is possible to reduce the bending moment value (bending stress) of the movable spring and increase the amount of deflection (deflection) of the tip of the movable spring.

For this reason, the present invention has a fixed contact, a movable spring member that has a contact portion that can come into contact with the fixed contact, one end of which is fixed and the other end of which is movable, and the other end of the movable spring member that is reciprocated. The switch is equipped with a drive rod 3 having one end fixed at an intermediate portion of the movable spring member such that the longitudinal direction of the movable spring member and its axis form a predetermined angle. The drive rod is made of an elastic member that deflects in response to deformation of the movable spring member caused by driving.

〔Example〕

This invention will be specifically explained with reference to the drawings.

FIG. 1a is a diagram showing an embodiment of the present invention showing the configuration of a switch for switching an input signal through a terminal 4a to either of the output terminals 1a, 1a.

The tip of the drive pin, which can be deformed by reducing the shaft diameter of the drive pin linearly reciprocated by the electromagnetic coil 5, and the middle part of the movable spring are fixed,
This is a switch that switches signals. Although it is generally required that the drive pin be made of an insulating material, it is most suitable for the drive pin to be made of glass fiber when repeatedly switching over a long life.

FIG. 1b is a diagram showing the bending moment that occurs at this time. When the shaft diameter of the drive pin is constant,
Areas Ma and Mb where the bending moment is large occur, and these Ma and Mb areas are vulnerable to fracture due to repeated stress, but are also weak areas.

In this way, concentration of bending moment at a certain point must be avoided due to life characteristics.
It is desirable to flatten the stress on the drive pin. In order to specifically realize this, it is necessary to change the shaft diameter of the drive pin according to the magnitude of the bending moment. If such a shape is used, it becomes possible to flatten the stress as shown in Fig. 4.
(indicated by M in figure b). In order to make the drive pin deformable, it is not necessarily necessary to form it from an integral part; for example, a coil spring b may be disposed in the middle of the drive pin as shown in FIG. Even if the rubber tube 7 is provided as shown, the same function can be obtained.

Further, the shape of the drive pin 3 may be not only a rod shape but also a thin plate shape.

[Effect of idea]

As mentioned above, in the switch of the present invention, the drive pin that transmits reciprocating linear drive is fixed to the movable spring, and abrasion powder from the drive pin is completely eliminated, so the contact stability of the contact portion 2a is improved. Furthermore, since the drive pin is deformable, the bending stress of the movable spring can be reduced, and a switch with a long life can be provided. Furthermore, the increase in the deflection angle of the movable spring makes it possible to ensure sufficient contact pressure against the fixed spring, resulting in the advantage of being able to provide a compact switch mechanism.

[Brief explanation of the drawing]

Fig. 1a shows an embodiment of the invention, Fig. 1b shows the bending moment of the movable spring during operation, Fig. 2 shows a second embodiment of the invention, and Fig. 3 shows the embodiment of the invention. Figure 4a is a diagram showing the operation of the present invention; Figure 4b is a diagram showing the stress distribution of the switch in Figure 4a; Figure 5a is a diagram showing the prior art (its 1), FIG. 5b is a diagram showing the stress distribution of the switch in FIG. 5a, and FIG. 6a is a diagram showing the prior art (Part 2). In the figure, 1 is a fixed contact, 2 is a movable spring member, 3 is a drive rod, 4 is a fixed part of the movable spring, 5 is an electromagnetic coil, and 6 is a coil spring.

Claims (1)

[Claims for Utility Model Registration] (1) A fixed contact 1; a movable spring member 2 having a contact portion capable of contacting the fixed contact, one end of which is fixed and the other end movable; and the movable spring member. A switch is provided with a drive rod 3, one end of which is fixed at an intermediate portion in the longitudinal direction of the movable spring member for reciprocating the other end of the movable spring member. One end of the rod is fixed to the intermediate portion so that the axis of the rod forms a predetermined angle, and the drive rod is an elastic member that deflects in response to deformation of the movable spring member caused by reciprocating drive. A switch characterized by: (2) The switch according to claim 1, wherein the drive rod has a cross section at an intermediate portion smaller than a cross section at both ends. (3) The switch according to claim 1 or 2, wherein the drive rod is made of glass fiber. (4) The switch according to claim 1, wherein the drive rod includes a coil spring. (5) The switch according to claim 1, wherein the drive rod includes a rubber member. (6) The switch according to claim 1, wherein the drive rod is made of a leaf spring.