JP3063187B2 - Snap switch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a snap switch having snap action means and means for forcibly opening a contact.

[0002]

2. Description of the Related Art Hitherto, forcible opening of a contact in a switch of this type has been employed in order to eliminate the cause of inability to open the contact, such as welding of a contact or breakage of a spring. Here, a conventional forcible opening and closing means of the contact will be described. For example, Japanese Patent Publication No. 50-127
The forcible opening means for the contacts of the snap switch described in Japanese Patent Publication No. 90 is disclosed in Japanese Patent Application Laid-Open Publication No. H10-15095. Has functions.

When the operating body is depressed, the cam-shaped slope of the operating body is brought into contact with each base end of the cam body rotatably supported at both ends below the movable contact piece. When the cam body is rotated about its support shaft by this, each end of the cam body hits the movable contact piece and pushes it up. As described above, the movable contact piece is pushed up by the rotation of the cam body, and the normally closed contact including the fixed contact and the movable contact is forcibly opened.

[0004] According to the forcible opening means for the contacts, the central portion of the movable contact piece is supported via a tongue piece for imparting a snap action function to the operating body, and one end is set at both ends thereof. Since the opening is performed by the pair of cam bodies, the forcible opening operation of the contacts is stably achieved. However, according to the above-described configuration, in the forcible opening operation of the contacts, one
Since a pair of cam bodies is required, the number of parts increases accordingly, and the assembling work is troublesome. So, conventionally,
As shown in FIG. 5 and FIG. 6, there is a type in which the contact is forcibly opened only by incorporating one cam body.

More specifically, as shown in FIG. 5, an operation body 2 is fitted to a switch case 1 so as to be axially movable, and one end of a U-shaped compression spring 3 for achieving a snap action function is operated by the above operation. The movable contact piece 4 is engaged with the engaging groove 2a of the body 2 and the other end thereof is engaged with the movable contact piece 4. It is constituted so that contact may be made to be able to come and go.

As shown in FIG. 6, a cam operation piece 8 is provided on the operation body 2 and a cam body 10 is turned on a cam-shaped slope 9a of a support piece 9 provided on the switch case 1. The operating body 2 is pressed down, the base end 10a of the lower end 8a of the operating body 8 is pressed, and the
c, the tip 10 of the cam body 10 is rotated.
The b contacts the one side projection 4a of the movable contact piece 4 and pushes it up. Thus, the cam body 10
The movable contact 5 is forcibly opened from the fixed contact 6 by the push-up operation of the movable contact piece 4 based on the rotation of. In the drawing, reference numeral 11 denotes a return spring of the operating body 2, 1
2 is a return spring of the cam body 10.

[0007]

However, according to the above-mentioned snap switch, since the forcible opening operation of the contact 5 is achieved by one cam body 10, the number of parts is reduced accordingly and the assembling work is easy. On the other hand, cam body 10
Of the movable contact piece 4, the movable contact piece 4 may be pushed up, but if the welding of the contacts 5 and 6 is firm, the movable contact In some cases, the movable contact 5 cannot be separated from the fixed contact 6 simply because the piece 4 pivots around the longitudinal direction. If this is to be achieved strongly, the compression spring 3 may be broken due to the twisting phenomenon, and the forced contact opening means may not operate effectively, and the snap action means may be damaged.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has a simple structure and a small number of parts, and reliably operates a snap action means and a forced opening means of a contact without damage. It is an object of the present invention to provide a snap switch capable of performing the following.

[0009]

According to a first aspect of the present invention, there is provided a snap switch, comprising: a rotatable cam body in which a forcible opening means of a contact abuts one side of a movable contact piece; And a stopper part with which the other side of the movable contact piece abuts by the turning operation of the movable contact piece. According to a second aspect, a holder is provided for preventing the movable contact piece from moving laterally in conjunction with the axial movement of the operating body.

[0010]

According to the first aspect of the present invention, when the movable contact piece is rotated by the cam body abutting on one side thereof, the other side of the movable contact piece abuts on the stopper. Even if the tip of the body hits one side of the movable contact piece,
The other side abuts against the stopper, and the reaction force can push up the movable contact piece in a stable state, so that the movable contact can be reliably separated from the fixed contact.
Moreover, according to the above configuration, the forced opening operation of the contact can be achieved with one cam body, so that the number of parts is reduced accordingly and the assembling work is easy. According to the second aspect of the present invention, since the holder for preventing the movable contact piece from moving sideways in conjunction with the axial movement of the operating body is provided, the snap action is caused by a torsion phenomenon or the like of the compression spring. Damage to the means can be effectively prevented.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 and 2 show a snap switch according to the present invention. The basic structure of the snap switch is the same as that shown in FIGS. The components are described with the same reference numerals. The difference between the one shown in FIG. 1 and the conventional one shown in FIG.
2 is rotatably supported on a bearing 13 provided on the switch case 1 and, as shown in FIG. 2, one side 4a of the movable contact piece 4 which is rotated by the tip 10a of the cam body 10. The stopper 14 protrudes from the switch case 1 in such a manner as to face the same.

The switch case 1 is provided with a holder 15 for preventing the movable contact piece 4 from moving laterally in conjunction with the axial movement of the operating body 2. As shown in FIG. 2, a stopper 16 is provided on the cover 32 so as to abut the tip 10a of the cam body 10 at a predetermined rotation position. FIG. 3 is an exploded perspective view of a main part showing the snap switch. As shown in FIG. 1, a pair of terminal blocks 17, 1 protruding from the inner wall of the switch case 1 at a predetermined interval.
7, bearings 13 and 13 are disposed to face each other.
A support shaft 10c of the cam body 10 is rotatably supported by bearing grooves 18 formed at one end thereof and formed at an open end.

A movable contact piece 4 is disposed over the fixed contact pieces 19, 19 fixed to the terminal blocks 17, 17, and a cam body 10 is attached to one side protruding piece 4a of the movable contact piece 4. Of the movable contact piece 4 on the other end 4b of the movable contact piece 4.
Are arranged so as to be able to contact each other. An operating body 2 for pressing the base end 10a of the cam body 10 is inserted through the through hole 4c of the movable contact piece 4, and one end of each of the U-shaped compression springs 3 is engaged with the engaging groove of the operating body 2. 2a and the other end thereof is locked to the movable contact piece 4. The operating body 2 is held by an operating body 22 via a return spring 23 so as to be axially movable, and an operating piece 31 protruding from the operating body 22 is provided.
Are slidably fitted in guide grooves 24 formed in the inner wall of the switch case 1. The head of the operation body 22 is slidably fitted in the guide port 25 of the switch case 1,
It is closed by the cover 32.

The cover 32 is provided with a projection 26 projecting therefrom.
The protruding pieces 26 are brought into contact with the bearings 13, 13 to close one end openings of the bearing grooves 18, 18, so that the support shaft 10 c of the cam body 10 is prevented from coming off, and is rotatable with respect to the bearing. It is pivoted. The cover 32 is provided with the above-mentioned stopper 16 so as to project therefrom, and the upper and lower locking projections 27 and 28 are locked to the locking projections 29 and 30 of the switch case 1, respectively. Furthermore, the holder 15 of the movable contact piece 4 is
7 and 17, the movement of the movable contact piece 4 in the longitudinal direction is regulated, and the projecting wall 16a projecting above the stopper 16 and the projecting wall 15a of the holder 15 form the movable contact. The movement of the piece 4 in the width direction is prevented. In addition,
The fixed contact piece 20 of the normally-open fixed contact 7 to which each movable contact 5 of the movable contact piece 4 comes and goes is fixed to a terminal block 21.

Next, the operation of the above configuration will be described. Now, when a pressing force is applied to the operation main body 22, the operation body 2 is pressed down against the spring pressure of the return springs 11 and 23, and an upward force acts on the movable contact piece 4 on the compression spring 3. As a result, the movable contact piece 4 is pushed up like a snap action. At this time, even when the movable contact 5 is strongly welded to the fixed contact 6, the lower end 3 of the operation piece 31 is moved from the state shown in FIG.
As shown in FIG. 4B, the base portion 10a of the cam body 10 is pressed by 1a to rotate the cam body 10 around the support shaft 10c, and the cam body 10 is moved by the distal end portion 10d of the cam body 10. While colliding against one side 4a of the piece 4, the movable contact piece 4 is pivoted around the longitudinal direction to push up the movable contact piece 4 as shown by C in FIG.

At this time, since the other side 4b of the movable contact piece 4 comes into contact with the stopper 14 at a predetermined turning position, the contact thereof is restricted, and the movable contact piece 4 is pushed up, and the movable contact piece 5 is raised. Can be forcibly and accurately separated from the fixed contact 6. Further, since the movable contact piece 4 is held by the holder 15 as shown in FIG. 1, the displacement of the movable contact piece 4 is suppressed and the compression spring 3 is twisted due to the restricting operation of the stopper 14. Can be effectively prevented from being broken.

[0017]

As described above, according to the first aspect of the present invention, when the movable contact piece is rotated by the cam body abutting on one side, the other side of the movable contact piece is stopped. Since the end portion of the cam body hits one side of the movable contact piece, the movable contact piece can be forcibly pushed up by the reaction force of the stopper,
The movable contact can be effectively separated from the fixed contact. According to the second aspect of the present invention, since the holder for preventing the movable contact piece from moving sideways in conjunction with the axial movement of the operating body is provided, the compression spring is twisted due to a twisting phenomenon or the like. There is no risk of damaging the premium means.

[Brief description of the drawings]

FIG. 1 is a front sectional view of an embodiment according to the present invention.

FIG. 2 is a side sectional view of one embodiment according to the present invention.

FIG. 3 is an exploded perspective view of a main part of one embodiment according to the present invention.

FIG. 4 is an explanatory diagram of an operation of a main part of one embodiment according to the present invention.

FIG. 5 is a front cross-sectional view of the related art.

FIG. 6 is a side cross-sectional view of the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Switch body 2 Operation body 3 Compression spring 4 Movable contact piece 5 Movable contact 6, 7 Fixed contact 10 Cam body 14 Stopper part 15 Holder part

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-25818 (JP, A) JP-A-59-79915 (JP, A) JP-A-50-49676 (JP, A) 12790 (JP, B2) (58) Field surveyed (Int. Cl. ⁷ , DB name) H01H 13/36

Claims (2)

(57) [Claims] A movable contact having both ends having an operating body which is set to be axially movable on a switch main body and which is biased at one end thereof, and a movable contact which is disposed opposite to a fixed contact so as to be able to contact and separate therefrom. A snap action means for snapping the movable contact piece when the contact is opened in conjunction with the axial movement of the operating body; and the movable means when the contact is opened in conjunction with the axial movement of the operating body. In a snap switch provided with forcible opening means for forcibly opening a contact, the forcible opening means for the contact comprises a rotatable cam body having a tip abutting on one side of a movable contact piece, and A snap switch for contacting the other side of the movable contact piece by a rotating operation by a body. 2. The snap switch according to claim 1, further comprising a holder for preventing the movable contact piece from moving laterally in conjunction with the axial movement of the operating body.