JPH0447869Y2 - - Google Patents

Description

[Detailed description of the invention] <Field of the invention> This invention is equipped with a pushbutton locking mechanism consisting of a cam that locks and holds the pushbutton in the push-in position and releases the lock when the pushbutton is pushed next time. This relates to push button switches.

<Prior art and its problems> FIG. 1 shows an example of a pushbutton switch equipped with a pushbutton locking mechanism. In the figure,
Reference numeral 1 denotes a switch case for an illuminated push button switch made of synthetic resin, and is composed of a switch case body 2 and a terminal base 3. Fixed contact pieces 4, 5, and 6 are insert-molded in the terminal base 3, and each of the fixed contact pieces 4, 5, and 6 has external terminals 4a, 5a, and 6a protruding from the terminal base 3. The base end of a movable contact piece 7 is rotatably locked to the inner end of the common fixed contact piece 4, and the distal end of the movable contact piece 7 is connected to and separated from the fixed contacts 8 and 9. A movable contact 10 is fixed. Reference numeral 11 denotes a reversing spring installed between the movable contact piece 7 and the common fixed contact piece 4, and constitutes a contact mechanism 12 together with the movable contact piece 7 and the fixed contact pieces 4, 5, and 6. Reference numeral 13 denotes a lever whose shaft portion 13a is supported by a bearing portion 2b formed on the intermediate wall 2a of the case body 2, and has a pressing portion 13b of the movable contact piece 7 on its lower surface, and its tip portion touches the lower surface of the push button 16. is in contact with.

The push button 16 has a movable base 17 and a movable base 17.
A light emitting element 19 is removably engaged and held within the cap 18. A pair of leg pieces 17a protrude from the lower end of the movable table 17.

Reference numeral 20 denotes both side surfaces 20 which are movably supported on the push button 16 and have recesses 20b and 20c at both diametrical ends of the rotating shaft 20a as shown in FIG. 3A.
d and 20e are flat cams, and this cam was made in the 1970s.
This cam 20 is similar to the one shown in Publication No. 17829, and this cam 20 is moved along a vertical slide guide surface 2d formed on the side wall 2c of the case body 2 on which the push button 16 is movably supported. During the pushing process of the push button 16, one side surface 20d of the push button 16 comes into sliding contact.

At the end position of the push button 16, the cam 2
After the lower recess 20b of 0 comes into contact with the lower step 2e and the cam 20 is rotated to the lock position R,
When the push button 16 moves in the return direction after releasing the pressure from this turning position R, the upper concave portion 20c of the cam 20 moves toward the upper stepped portion 2, as shown in FIG. 3B.
This pushbutton 16 is kept locked by contacting f. Next, when the push button 16 is pushed in from this lock holding position S, the lower end of the cam 20 comes into contact with the downwardly inclined slide guide surface 2g for return, as shown in FIG. The upper concave portion 20c is rotated to the unlocked position T, and the other side surface 20e returns while contacting the vertical slide surface 2d.

However, as the push button switch becomes smaller, it is necessary to reduce the return amount x of the cam 20. As shown in A, even if the push button 16 is pushed in from the cam lock position, the cam 20 cannot be easily unlocked because the amount of rotation of the cam 20 is small, so the width of the cam 20 must be made small. In this way, cam 2
When the width of 0 is reduced, as shown in Figure 3A,
Since the overlapping amount y when the lower end of the cam 20 contacts the lower step portion 2e is small, the amount of rotation of the cam 20 becomes unstable, and the cam 20 rotates to the lock release position T as shown in the imaginary line, and the cam 20 is locked. not,
The locking operation of the pushbutton 16 has the drawback of causing malfunction.

<Purpose of the invention> This invention was made to eliminate the above-mentioned drawbacks, and the purpose is to provide a pushbutton switch that does not cause any malfunction in the locking operation of the pushbutton even if the cam is made small. do.

<Structure and effect of the invention> The pushbutton switch according to this invention is rotatably supported by the pushbutton, and both ends of the rotating shaft in the diametrical direction are formed into a smooth letter 3 shape, and a recess is formed in the center. a cam having flat sides on both sides; and a cam formed on a side wall of a case in which the push button is movably supported, one side of the cam comes into sliding contact during the pushing process of the push button, and the other side comes into sliding contact during the return process. A vertical slide guide surface, an inclined slide guide surface for locking that reaches below the lower step where the lower end of the cam comes into contact with the push button near the end of the push button and rotates the cam to its lock position; The lower recess of the cam comes into contact at the end position of the pushing process to restrict the rotation of the cam, and the upper recess of the cam contacts the lower recess of the cam when the push button moves in the return direction from the rotation restriction position. An upper step part that comes into contact with the push button to lock it, and a return part that contacts the lower end of the cam when the push button is pushed in from the lock holding position and turns the upper recessed part of the cam to the unlocked position. and a downwardly inclined slide guide surface.

As described above, a locking inclined slide guide surface is provided that reaches below the lower step part that contacts the lower end of the cam near the end of the pushing process of the pushbutton and rotates the cam to its lock position. The structure is such that the lower concave part of the cam comes into contact with the lower stepped part at the end of the pushing process to restrict the rotation of the cam, so even if the cam is made smaller, there is no risk of malfunction in the locking operation of the push button. .

Furthermore, since both ends of the cam are formed into a smooth 3-shape, when the cam contacts and slides on the locking inclined slide guide surface, downwardly inclined slide guide surface, etc., it slides effortlessly and smoothly. do.

<Description of Embodiment> An embodiment of this invention will be described below with reference to the drawings. FIG. 2 is a cross-sectional view of the main parts of the push button locking mechanism according to the embodiment of this invention.

In the figure, the same parts as in FIG. 3 are given the same numbers. That is, 20 is the push button 16
Both side surfaces 20d are rotatably supported by the rotary shaft 20a, and both diametrical ends of the rotating shaft 20a are formed into a smooth letter 3 shape, and have recesses 20b and 20c in the center.
20e is a flat cam, 2d is formed on the side wall 2c of the case 2 on which the push button 16 is movably supported;
A vertical slide guide surface 21 is a vertical slide guide surface with which one side surface 20d comes into sliding contact and the other side surface 20e comes into sliding contact during the return process. The guide body 2e is formed with a locking inclined slide guide surface 21a for turning to the locking position R, and the guide body 2e is the lower part that the lower concave portion 20b of the cam 20 comes into contact with at the end position of the push button 16 to restrict the turning of the cam 20. At the stepped portion, the inclined lower end of the locking inclined slide guide surface 21a is located below the lower stepped portion 2e. 2f is a cam 20 when the push button 16 is moved in the return direction from the rotation restriction position U by the lower step portion 2e.
The upper step part 2g, which the upper recess 20c comes into contact with to lock and hold the push button 16, is the upper step part 2g that the lower end of the cam 20 comes into contact with when the push button 16 is pushed in from the lock holding position S. This is a downwardly inclined slide guide surface for returning the recess 20c to the unlocked position T.

In the above configuration, when the push button 16 is pressed, the lever 13 rotates clockwise around the shaft portion 13a and moves the movable contact piece 7 downward, so that the movable contact 10 is moved away from the fixed contact 9. It can be brought into contact with the fixed contact 8 by switching. When the pressing force of the push button 16 is released, the lever 13
is rotated counterclockwise by the elastic return force of the movable contact piece 7 and returns to its current state.

When the push button 16 is pressed, the cam 20 moves onto the vertical slide guide surface 2 formed on the side wall 2c of the case body 2, as shown in FIG. 2A.
d, one side surface 20d of the push button 16 slides into contact with the push button 16 in the pushing process.

At a position near the end of the pushing process of the push button 16, the lower end of the cam 20 comes into contact with the locking inclined slide guide surface 21a of the guide body 21, and the cam 20 is rotated to its lock position R. When the cam 20 rotates to this lock position R, the lower recess 20 of the cam 20 reaches the final position of the push button 16.
b comes into contact with the lower step portion 2e to restrict the rotation of the cam 20.

When the push button 16 moves in the return direction after releasing the push button from the rotation restriction position U shown in FIG. do.

Next, when the push button 16 is pushed in from this lock holding position S, the lower end of the cam 20 comes into contact with the downwardly inclined slide guide surface 2g for return, as shown in FIG. The upper concave portion 20c is rotated to the unlocked position T, and the other side surface 20e returns while contacting the vertical slide surface 2d.

As is clear from the above, as the push button switch becomes smaller, the return amount x of the cam 20 increases.
In order to reduce the return amount x of the cam 20, even if the width of the cam 20 is made small, the lower end of the cam 20 closes to the locking inclined slide at a position near the end of the pushing process of the push button 16. The cam 20 contacts the guide surface 21a and rotates to its lock position R. When the cam 20 rotates to the lock position R, the lower concave portion 20b of the cam 20 contacts the lower stepped portion 2e at the final position of the pushing process of the push button 16. The rotation of the cam 20 can be restricted by coming into contact with the push button 1, even if the cam 20 is made small.
There is no risk of malfunction in the locking operation of 6.

Furthermore, since both ends of the cam 20 are formed into a smooth 3-shape, the cam 20 slides in contact with the locking inclined slide guide surface 21a, the downwardly inclined slide guide surface 2g, etc. without any force. Slides smoothly.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an example of a push button switch equipped with a push button locking mechanism, Fig. 2 is a sectional view showing a push button locking mechanism according to this invention, and Fig. 3 is a sectional view of a conventional push button switch. FIG. 3 is a sectional view showing the lock mechanism. 2...Case, 2c...Side wall, 2d...Vertical slide guide surface, 2e...Lower step, 2f...
Upper step part, 2g...downward inclined slide guide surface for return, 16...push button, 20a...rotation shaft,
20b, 20c... recess, 20d, 20e... both sides, 20... cam, R... lock position, S...
Lock holding position, T...Lock release position, U...
Lock regulation position, 21a... Slanted slide guide surface for lock, 21... Guide body.

Claims (1)

[Scope of utility model registration request] A cam rotatably supported by the push button and having both diametrical ends of the rotating shaft shaped like a smooth letter 3 and having flat sides on both sides and having a recess in the center, and the push button being movable. a vertical slide guide surface formed on the side wall of the supported case, with which one side of the cam slides into contact during the pushing process of the push button and the other side slides into contact during the return process, and a position near the end of the pushing process of the push button. The lower end of the cam comes into contact with the locking slope slide guide surface reaching below the lower step, which rotates the cam to its lock position.At the end of the pushing process of the push button, the lower recess of the cam comes into contact with this surface. a lower stepped portion that restricts the rotation of the cam; an upper stepped portion that is brought into contact with the upper recessed portion of the cam to lock and hold the push button when the push button moves in the return direction from the rotation restricting position; The pushbutton is characterized by having a downwardly inclined slide guide surface for return, which the lower end of the cam comes into contact with when the pushbutton is pushed in from the lock holding position, thereby pivoting the upper recessed portion of the cam to the unlocking position. Button switch.