JPH0715067Y2 - switch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION << Industrial Application Field >> The present invention relates to a switch used in, for example, an electromagnetic switch.

<< Prior art >> In the case of an electromagnetic switch, etc., in consideration of reliability at the time of switching, a twin contact type having two switching contacts in one circuit and a snap action mechanism for simultaneously performing snap action switching between these two contacts. Switch is used.

5 to 8 show an example of such a conventional twin contact type switch.

In the figure, this switch 41 includes a housing 44 including a case 42 having an open upper surface and a cover 43 for closing the upper opening of the case 42, a push button 45, a return coil spring 46, and terminals 47 and 48. , Fixed contact 49, movable piece 50,
It is composed of a reversing spring 51 and the like.

The movable piece 50 is formed of a strip-shaped metal plate having a spring property. One end side of the movable piece 50 is separated by a slit 52 to form a pair of movable contact piece portions 53, 53.
Further, between the movable contact pieces 53, 53 and the other end, a strip-shaped return spring portion 54, one end of which is swingable, is provided. In addition, a strip-shaped reversing spring is provided between the tip portion of each movable contact piece portion 53 and the swing tip portion of the return spring portion 54.
An end portion 51 is interposed in such a manner that one end portion is swingably engaged with the movable contact piece portion 53 and the return spring portion 54 to be bent in an arc shape.

In this switch structure, when the push button 45 is not pressed, the push button 45 is pressed by the urging force of the return coil spring 46.
45 is pushed up, and the entire return spring portion 54 of the movable piece 50 is rotated clockwise in FIG. 5 and is displaced upward. The reversing spring 51 is rotated counterclockwise in FIG. 5 and is arranged at the position shown by the solid line in FIG. Further, as a result, each movable contact piece 53 is
The movable contact 55 attached to the tip of each movable contact piece 53 is rotated counterclockwise in FIG. Each is strongly abutted. That is, the contact is in the on state.

Next, when the push button 45 is pushed down from this state, the return spring portion 54 is pushed downward, and the whole of the return spring portion 54 is rotated in the counterclockwise direction in FIG. 51 is also rotated clockwise in FIG. Further, when the reversing spring 51 is rotated to a preset position, the whole reversing spring 51 suddenly rotates in the clockwise direction in the figure, which causes the movable contact pieces 53 to move in the figure. The turning power is given in the clockwise direction. Then, the movable contact piece portion 53 is snap-switched and displaced to the position shown by the alternate long and short dash line in the figure, and the movable contact 55 separates from each corresponding fixed contact 49 and is turned off.

Also, if the pressing force of the push button 45 is released from this state,
The push button 45 is pushed up by the urging force of the return coil spring 46, and the entire return spring portion 54 of the movable piece 50 is also pushed up. Then, it is rotated clockwise in FIG. 5 and displaced upward. At the same time, the reversing spring
When 51 is also rotated counterclockwise and rotated to a preset position, the entire reversing spring 51 suddenly rotates counterclockwise in the figure, which causes each movable contact. A rotational force in the counterclockwise direction in the figure is applied to the piece portion 53. Then, the movable contact piece portion 53 is snap-switched and rapidly displaced to the position shown by the solid line in the figure, and again as shown by the solid line in the figure, the movable contact 55 is fixed to the corresponding fixed contact 49. Each is strongly abutted and turned on.

<Problems to be Solved by the Invention> However, in the structure of the conventional switch 41, the return spring portion 54 is formed for each movable contact piece portion 53, and the reversing spring 51 is also formed for each movable contact piece portion 53. Is formed.
Therefore, the width dimension of each return spring portion 54 is reduced, and accordingly, the area of the portion swingably coupled to the reversing spring 51 (the portion indicated by the symbols A and B in FIG. 6) is also reduced. .
For this reason, the engaging surface pressure per unit area at the joint portion becomes high, and it is difficult to disperse the concentration of stress at the rotation fulcrum portion during the reversing operation. As a result, mechanical fatigue is increased, the life is shortened, and the reliability is deteriorated. Further, since it is necessary to individually incorporate the reversing springs 51, there is a problem that the number of assembling steps is large and the cost is disadvantageous.

The present invention has been made in view of the above problems, and an object thereof is to provide a switch having a structure capable of improving workability, reliability, and life.

<Means for Solving the Problems> In order to achieve the above object, the present invention is a switch having twin contacts that are snap-switched, in which a housing and one movable end are separated into two. A pair of movable contact pieces formed by punching the movable contact piece while the other end of the movable contact piece is punched, and a swingable single strip having a stress dispersion hole in the center thereof A movable piece whose other end is fixed to the housing, a terminal attached to the housing with two fixed contacts corresponding to the movable contact, and the pair of movable contact pieces. One end corresponds to 2 parts
And the other end is integrated, and the one end is swingably engaged with the tip ends of the pair of movable contact pieces, and the other end is swung with the swing tip of the return spring part. A reversing spring for snap switching, which is freely engaged, and a push button for pressing the return spring portion from the outside are provided.

<< Embodiment >> An embodiment of the present invention will be described in detail below with reference to the drawings.

1 to 4 show an example of a switch according to the present invention.

In the figure, this switch 1 comprises a housing 2, a push button 3, a return coil spring 4, terminals 5, 6, a pair of fixed contacts 7, a movable piece 8, a reversing spring 9 and the like. .

The housing 2 is formed of a case 10 made of synthetic resin and a cover 11 made of synthetic resin. Of these, the case 10 is formed in a box shape having a bottom surface 10a and four side surfaces 10b and an open top surface. Further, a bottomed cylindrical recess 12 for accommodating the return coil spring 4 and the like is formed in the central portion of the bottom surface 10a in a state where the recess 12 is wide in the left-right direction. Then, engaging holes 10c and 10d are respectively provided on both left and right sides of the recess 12 between the engaging holes 1c.
Parts of the terminals 5 and 6 are fitted to 0c and 10d, and further, they are caulked to the case 10 for positioning. Of these terminals 5 and 6,
One terminal 5 extends straight upward. On the other hand, the other terminal 6 integrally includes a lead terminal portion 6a extending straight upward and a pair of portions 6b bent from the lead terminal portion 6a at a substantially right angle and extending along the inner surface of the bottom surface 10a. The fixed contact 7 is attached to the tip of each of the portions 6b.

On the other hand, the cover 11 is attached to the case 10 with the top opening of the case 10 closed. The central portion 11a of the cover 11 is bulged upward so as to form a part of the internal space of the housing 2. A bearing portion 11b having a through hole 13 is integrally provided at the center of the central portion 11a. Further, the outer peripheral flat surface portion 11c of the central portion 11a has terminals when the cover 10 is assembled.
Holes 10d and 10e, through which 5 and 6 are penetrated, are provided so as to penetrate vertically.

Next, the push button 3 is made of a synthetic resin material. Then, the push button 3 has a rod-shaped operating portion 3a that projects through the through hole 13 to the outside of the housing 2, a guide portion 3b that is slidably inserted in the recess 12, and the operating portion.
The main body portion 3c connecting between the 3a and the guide portion 3b is integrally provided, and an opening 14 that greatly penetrates left and right is formed in an intermediate portion of the main body portion 3c. Also,
In the opening 14, protruding piece portions 3d, 3e protruding from the upper and lower inner surfaces are provided, respectively. The push button 3 is attached in a state in which the return coil spring 4 interposed in the recess 12 is compressed. When the cover 10 is attached with the guide portion 3b inserted into the recess 12 and the operation portion 3a inserted into the through hole 13 of the cover 10, the body portion 3c is covered by the urging force of the return coil spring 4. It is held in a state where it bumps against the inner surface of 10 and is positioned. Further, when assembled in this way, the movable piece 8 is made to penetrate into the opening 14 of the main body portion 3c, and the intermediate portion of the return spring portion 20 described later is arranged between the movable piece 8 and the protruding piece portions 3d, 3e. .

The movable piece 8 is formed of a strip-shaped metal plate having a spring property. A slit 15 is provided on one end side of the movable piece 8, and the slit 15 forms a pair of movable contact piece portions 16, 16. The other end of the movable piece 8 is bent downward and fixed to the terminal 5 with a rivet 19.

A movable contact 17 corresponding to the fixed contact 7 is attached to the lower surface of each of the movable contact pieces 16, 16 and an engaging hole 18 (fourth contact hole) is formed at the tip of each movable contact piece 16, 16.
(See the figure). Further, the movable piece 8 is integrally formed with a strip-shaped return spring portion 20 between the movable contact piece portion 16 and the other end, which is cut out in a U-shape between these portions.
The return spring 20 has a single strip shape formed by punching out the movable contact pieces 16 and 16 while the other ends of the movable contact pieces 16 and 16 are connected, and the other end side is fixed and movable. The contact piece portion 16 side serves as a swing end, and an engaging projection 20a is integrally provided on the swing end. Further, a stress distribution hole 20c for distributing stress concentration in the root portion 8a on the other end side is provided in the central portion of the return spring 20 along the longitudinal direction. On the other hand, the left and right leg portions 8b along the return spring portion 20 are provided with a bent portion 8c in the middle thereof to effectively shorten the distance between the tip of the movable contact piece portion 16 and the root portion 8a, and return. The swinging end of the spring portion 20 is in a state of protruding toward the movable contact piece portion 16 side. The tip of the return spring 20 and the movable contact piece
A reversing spring 9 is interposed between 16 and.

The reversing spring 9 is formed of a metal plate having a spring property. Then, the reversing spring 9 is provided with a wide slit 21 from one end side, and a pair of movable contact piece portions 16 is provided at this one end side.
The pair of reversing spring portions 9a and 9b corresponding to the above are integrally formed. In addition, locking protrusions 9c (see FIG. 1) that are inserted into the engagement holes 18 and are swingably coupled are provided at the tips of the reversing spring portions 9a and 9b, respectively. On the other hand, on the other end side of the reversing spring 9, an engaging projection 9d that is swingably engaged with the swing tip of the return spring portion 8 (see FIG. 1).
Is provided. Further, in the reversing spring 9, the tip ends of the reversing spring portions 9a and 9b are swingably coupled to the engaging holes 18, respectively, and the other end side is swingably coupled to the swing tip of the return spring portion 8. In this state, it is bent and attached between the return spring portion 8 and the movable contact piece portion 16 in a substantially U shape.

In the switch 1 configured as described above, when the push button 3 is not pressed, the push button 3 is pushed up by the biasing force of the return coil spring 4, and the return spring portion 20 of the movable piece 8 is entirely moved to the first position. It is in a state of being rotated clockwise in the figure and displaced upward. And the reversing spring 9
Is rotated counterclockwise in FIG. 1 and is arranged at the position shown by the solid line in FIG. Further, as a result, each movable contact piece portion 16 is rotated counterclockwise in the figure with the root portion 8a as a fulcrum, and the movable contact 17 attached to the tip end portion of each movable contact piece portion 16, Corresponding fixed contact 7
Are strongly abutted against each other. That is, the contact is in the on state.

Next, when the push button 3 is pushed down from this state, the return spring portion 20 is pushed downward, and the entire return spring portion 20 is rotated counterclockwise in FIG. Is also rotated clockwise in FIG. Also,
When the reversing spring 9 is rotated to a preset position, the whole reversing spring 9 suddenly rotates in the clockwise direction in the figure, which causes the movable contact pieces 16 to move in the clockwise direction in the figure. A turning force is applied in the turning direction. Then, the movable contact piece portion 16 is snap-switched and displaced to the position shown by the alternate long and short dash line in the figure, and the movable contact point 17 separates from the corresponding fixed contact point 7 and is turned off.

Further, when the pressing force of the push button 3 is released from this state,
The push button 3 is pushed up by the urging force of the return coil spring 4, and the entire return spring portion 20 of the movable piece 8 is also pushed up and rotated clockwise in FIG. 1 to be displaced upward. At the same time, the reversing spring 9 is also rotated counterclockwise, and when it is rotated to a preset position, the entire reversing spring 9 suddenly rotates counterclockwise in FIG. As a result, a rotational force in the counterclockwise direction in the figure is applied to each movable contact piece portion 16. Then, the movable contact piece 16 is abruptly displaced to the position shown by the solid line in the figure, and again the movable contact as shown by the solid line in the figure.
17 is strongly abutted on each corresponding fixed contact 7 to be turned on.

Therefore, in the switch 1 configured as described above, the return spring portion 20 is not formed for each movable contact piece 16 and is formed in one strip shape, and the reversing spring 9 is also not formed for each movable contact piece 16 and the return spring 20 is formed. Since the pair of reversing spring portions 9a and 9b are integrated at the portion freely coupled to the portion 20, the pair of reversing spring portions 9a and 9b can be assembled at once at the time of assembly. As a result, workability is improved and cost can be reduced. In addition, since the swingable joint portion between the reversing spring 9 and the return spring portion 20 can be joined in a state where a large width dimension is secured, the concentration of stress in this joint portion is dispersed and the relationship per unit area is dispersed. The contact pressure can be reduced. As a result, mechanical fatigue can be reduced and the life can be improved, and the reliability is improved.

<< Effects of Device >> As described above, according to the switch of the present invention,
The return spring part is not formed for each movable contact piece but is formed in one strip shape, and the reversal spring is not formed for each movable contact piece, and the pair of reversal spring parts is integrated at the portion freely coupled with the return spring part. Therefore, the pair of reversing spring portions can be assembled at one time at the time of assembly. As a result, workability is improved and cost can be reduced. In addition, since it is possible to connect the reversing spring and the return spring portion at the swingable joint portion while ensuring a large width dimension, the stress concentration at this joint portion can be dispersed and the engagement surface per unit area can be dispersed. The pressure can be reduced. As a result, mechanical fatigue can be reduced and the life can be improved, and the reliability is improved.

[Brief description of drawings]

FIG. 1 is a vertical side view of a switch according to an embodiment of the present invention, FIG. 2 is a top view showing the internal structure of the same switch with a cover removed, and FIG. 3 is a partial cutaway view of the same switch. 1 is a side view showing the internal structure from a direction different from that of FIG. 1, FIG. 4 is a perspective view of an essential part of the same switch, FIG. 5 is a vertical side view of a conventional switch, and FIG. 6 is shown in FIG. FIG. 7 is a top view showing the internal structure by removing the cover of the same switch. FIG. 7 is a side view showing the internal structure from a direction different from that of FIG. 5 by breaking a part of the same switch shown in FIG. FIG. 8 is a perspective view of an essential part of the same switch shown in FIG. 1 ... switch, 2 ... housing, 3 ... pushbutton,
4 …… Return coil spring, 5,6 …… Terminal, 7 ……
Fixed contact, 8 ... movable piece, 9 ... reversing spring, 10 ... case, 11 ... cover, 16 ... moving contact piece, 17 ... moving contact, 20 ... return spring section.

Claims (1)

[Scope of utility model registration request] 1. A switch having twin contacts that are snap-switched, wherein a housing, a pair of movable contact pieces having one end separated into two movable contacts and the movable contact pieces are provided. Has a swingable single strip-shaped return spring portion formed by punching out the movable contact piece portion while the other end side of the housing is connected and having a stress distribution hole in the center thereof, and the other end side of the housing is A movable piece fixed to the housing, a terminal attached to the housing by providing two fixed contacts corresponding to the movable contact, and one end separated into two corresponding to the pair of movable contact piece portions and the other end. And the one end is swingably engaged with the tip ends of the pair of movable contact pieces, and the other end is swingably engaged with the swing tip of the return spring portion. For snap switching And rolling springs, switches, characterized in that a push button to be pressed from outside the return spring portion.