JPH04503Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention provides a double cam including a heart-shaped cam, a U-shaped member that engages with the heart-shaped cam, and biasing means for the U-shaped member. This relates to a step-operation push button switch.

[Background of the invention] A push button switch has a slider to which a movable contact piece is fixed, a casing that slidably supports the slider, and a fixed contact piece implanted in the casing. A heart-shaped cam is provided, one end of the U-shaped member is engaged with the heart-shaped cam, and the other end of the U-shaped member is rotatably supported with respect to the housing, and By providing means for biasing the shaped member toward the heart-shaped cam,
It is known that the slider described above can be provided with a two-stage actuation function. FIG. 2 is an explanatory diagram of this type of push button switch, and FIG. 3 is a perspective view of a portion of the constituent members.

1 is a housing, 6 is a base member constituting the bottom wall thereof, and these two members support the slider 4 so as to be slidable in the longitudinal direction. 9 is a fixing member.

2 through the base member 6 to the above-mentioned casing 1.
The fixed contact pieces 7 are fixed, and the movable contact piece 5 is fitted onto the slider 4. As a result, as the slider 4 slides, the movable contact piece 5 comes into contact with either of the two fixed contact pieces 7, 7, and conduction is switched. In FIG. 3, the solid line 5 represents the disassembled movable contact piece, and the phantom line 5' represents the movable contact piece assembled into the slider 4. 12 is a knob for a push button, 11 is a press-fit rod connecting the slider and the knob, and 10 is a return spring.

In order to provide a two-stage operating function to the sliding movement of the slider 4, the slider 4 is provided with a heart cam 4a and a U-shaped rod-like member 2 that engages with the heart cam 4a. One end 2a of the U-shaped member 2 is fitted into a pivot hole 1a provided in the housing 1, and the other end 2b is engaged with a groove 4b of a heart cam 4a. In the push button switch configured as described above, when a pressing force is applied to the convex side surface of the U-shaped member 2 as shown by arrow P, the free end 2b of the U-shaped member 2 moves into the heart cam groove as the slider slides. 4b and performs a two-stage operating function. 4c is a groove provided in the slider 4 to avoid interference with one end 2a of the U-shaped member.

In order to apply a pressing force in the direction of arrow P to the above-mentioned U-shaped member 2, conventionally, as shown in FIG.
A shape spring U is interposed. 1i is a U-shaped spring device formed by expanding a portion of the housing 1, and 1j is a hook-shaped projection integrally molded on the edge thereof.

In the conventional push button switch (FIG. 4) constructed as described above, the U-shaped member 2 is biased with a pressing force in the direction of the arrow P by the U-shaped spring U.
The function of stage operation is fulfilled. When the above-mentioned U-shaped spring is installed in a predetermined position, it engages with the protrusion 1j, so there is no risk of it falling off.

However, the conventional push button switch described above has the following problems.

(a) It is not easy to insert the U-shaped spring through the opening 1k of the mounting portion 1i while pressing it, and it is not possible to check whether the mounting state is good or not. Furthermore, once installed, it is extremely difficult to remove.

(b) The contact point between the U-shaped spring and the U-shaped member 2 is unstable. That is, the U-shaped spring U is interposed between the U-shaped member 2 and the inner surface of the attachment part 1i, and maintains a stable position and posture depending on the conditions at the site while being restrained from restoring by its own elasticity. As a result, the state of contact between the U-shaped spring and the U-shaped member 2 is not constant. For this reason, the locking function of the push button switch is unstable and its operation reliability is low.

In order to solve the above-mentioned problems, make it easier to attach and detach the U-shaped spring, and stabilize the locking function, it is effective to make improvements as shown in FIGS. 5 and 6. The structure related to this improvement was created by the present inventor and is currently being filed separately (hereinafter referred to as the "prior application").

FIG. 5 is a cross-sectional view of an example of a push-button switch that is improved by applying the invention of the prior application to the conventional push-button switch shown in FIG. 4, and FIG. 6 is an exploded perspective view of the same. Housing 1, pivot hole 1a, U-shaped rod-shaped member 2, slider 4, movable contact piece 5, base member 6, fixed contact piece 7, with the same drawing reference numbers as in FIGS. 2 to 4. , the fixing member 9, the return spring 10, and the knob 12 are the same or similar components as in a conventional push button switch.

The protrusion 6a of the base member 6 shown in FIG. 6 is fitted into the through hole 1d of the housing 1 with a snap fit. With this configuration, assembly work is easy.

The bracket 8 is fitted into a groove 1c formed on the side surface of the housing 1, and has both ends 8a engaged with through holes 9b of the fixing member 9 to be caulked.
9a is a through hole through which the slider 4 is passed. A knob 11 is fixed to the tip of the slider passed through this through hole via a press-fit rod 12, and a return spring 10 is disposed between the knob 11 and the fixing member 9.

In addition, a U-shaped plate spring 30 is mounted on the top surface of the housing 1.
A housing portion 1b is provided, and this housing portion 1b is provided with an opening portion 1k for inserting the plate spring 30 and a long hole 1g so that the U-shaped member 2 can be assembled at a predetermined position from the outside of the housing 1.

FIG. 7 shows an enlarged view of the vicinity of the portion shown in FIG. 5, taken along a different plane from that shown in FIG. 5.

1 is the aforementioned casing, and 2 is a U-shaped member.
The housing 1 has a housing portion 1r for the U-shaped leaf spring 30.
1k is the front opening and 1m is the rear wall.

The top wall of the storage portion 1r is provided with a long hole 1e for engagement in a direction perpendicular to the plane of the drawing.

On the other hand, R-shaped protrusions 30a and 30b are provided at both ends of the U-shaped leaf spring 30, respectively, and protrude laterally, and one of the R-shaped protrusions 30a abuts against the U-shaped member 2. It's under pressure. The other R-shaped protrusion 30b is positioned to engage with the aforementioned elongated engagement hole 1e.

A protrusion 1f is fixed to the inner surface of the rear wall 1m, and this protrusion 1f supports the lower side of the central bent portion 30c of the U-shaped leaf spring 30.

In the push-button switch of the prior application (FIGS. 5 to 7) constructed as described above, as can be easily understood from FIG. Since it is supported and positioned by the engagement hole 1e, the mounting state is stable.Since it is in point contact with the U-shaped member 2, the biasing force is almost constant. , engagement hole 1
Using e (for example, with the tip of a screwdriver) arrow P
When force is applied in this direction, the U-shaped leaf spring bends as shown by the imaginary line, making it easy to attach and detach.

The present inventor conducted a practical test on the push-button switch of the prior application, and as a result, it was confirmed that the above-mentioned effects could be obtained, but the following defects were discovered.

That is, when a force is accidentally applied to the U-shaped leaf spring 30 in the shape shown by the imaginary line in FIG. 7 for some reason, the U-shaped leaf spring 30 bends to the left in the figure. There is a risk of it slipping out.

[Purpose of invention]

This idea was created in view of the above circumstances.
This is an attempt to provide a push button switch that is further improved on the push button switch of the prior application and is free from the risk of the U-shaped leaf spring coming off.

[Summary of the idea]

As is clear from the above object, the present invention includes a slider to which a movable contact piece is fixed, a casing that slidably supports the slider, and a fixed contact piece implanted in the casing, The slider is provided with a heart-shaped cam, a U-shaped member is provided, one end of the U-shaped member is rotatably supported relative to the housing, and the other end of the U-shaped member is rotatably supported. A U-shaped leaf spring that engages with the heart-shaped cam and presses the U-shaped member toward the heart-shaped cam is provided, a storage portion for the U-shaped leaf spring is provided in the housing, and the storage portion is provided with a storage portion for the U-shaped leaf spring. A protrusion for supporting the centrally curved lower side of the U-shaped leaf spring is provided on the inner wall of the section, and R-shaped protrusions that project laterally are formed at both ends of the U-shaped leaf spring. A structure in which an R-shaped protrusion is brought into contact with a U-shaped member, and the other R-shaped protrusion is engaged with an engagement hole provided in the wall of the storage section for positioning (prior application)
Applies to push button switches. The push button switch of the present invention is provided with a hook-shaped protrusion at the tip of the protrusion that supports the U-shaped leaf spring, and
It is characterized in that the U-shaped leaf spring is provided with a hole that engages with the hook-shaped projection.

[Example of idea]

Next, one embodiment of the present invention will be described with reference to FIG. This FIG. 1 is a sectional view corresponding to FIG. 7 in the earlier application, and the same drawing reference numerals as in FIG. 7 are given to the same components as in the earlier application.

Reference numeral 1' denotes a housing in this embodiment, and the top wall thereof is provided with an engagement hole 1e similar to that in the previous application. 1f is a storage part for the U-shaped leaf spring 30';
m is the back wall.

The U-shaped leaf spring 30' of this embodiment differs from the U-shaped leaf spring 30 of the prior application (FIG. 7) as follows.
An engagement hole 30d is provided near the bent portion 30c at the center.

On the other hand, a hook-like protrusion 1f -1 ' that engages with the engagement hole 30d is provided at the tip of a protrusion 1f' that is fixed and protrudes forward from the rear wall 1m of the housing _1' .

Push button switch configured as above (Figure 1)
For some reason, the U-shaped leaf spring 30'
Even if it is bent as shown by the imaginary line, the hook-like protrusion 1f _-1 ′ engages with the engagement hole 30d, so U
There is no risk that the character-shaped leaf spring 30' will slip out to the left in the figure.

[Effect of idea]

As described in detail above, the slider has a movable contact piece fixed thereto, a housing that slidably supports the slider, and a fixed contact piece implanted in the housing, and the slider has a heart attached to the slider. A U-shaped cam is provided, and a U-shaped member is provided, one end of the U-shaped member is rotatably supported with respect to the housing, and the other end of the U-shaped member is engaged with the heart-shaped cam. A U-shaped leaf spring that presses the U-shaped member toward the heart-shaped cam is provided in the housing, and a storage portion for the U-shaped leaf spring is provided in the housing, and a U-shaped leaf spring is provided on the inner wall of the storage portion. A protrusion is provided to support the lower side of the central curve of the U-shaped leaf spring, and R-shaped protrusions are formed at both ends of the U-shaped leaf spring, respectively, and extend laterally, and one of the R-shaped protrusions is attached to the U-shaped leaf spring. The structure according to the present invention is applied to a push button switch which is brought into contact with a letter-shaped member and positioned by engaging the other R-shaped protrusion with an engagement hole provided in the wall of the housing part, and the above-mentioned U-shaped plate is manufactured. A hook-shaped protrusion is provided at the tip of the protrusion that supports the spring, and a U
By providing a hole in the U-shaped leaf spring that engages with the hook-like protrusion, even if an unexpected force that causes the U-shaped leaf spring to bend is applied for some reason, the leaf spring will not move from its predetermined mounting position. It has an excellent practical effect in that there is no risk of it slipping out.

[Brief explanation of drawings]

FIG. 1 is a partial sectional view showing one embodiment of the push button switch of the present invention. Figures 2 to 4 show an example of a conventional two-stage push button switch, in which Figure 2 is a vertical sectional view, Figure 3 is an exploded perspective view of the components of the lock mechanism, and Figure 4 is the lock mechanism. FIG. 5 to 7 show one embodiment of the push button switch of the earlier application, in which FIG. 5 is a front view drawn in cross section, FIG. 6 is an exploded perspective view, and FIG. 7 shows the part shown in FIG. 5. FIG. 6 is an enlarged sectional view taken along a different plane from FIG. 5; 1... Housing, 1e... Engagement hole, 1f, 1f'...
Projection, 1f _-1 ′...Hook-like projection, 1m...Rear wall,
2... U-shaped member, 30, 30'... U-shaped leaf spring, 30a, 30b... R-shaped projection, 30c...
Central bent part, 30d...Engagement hole, 4...Slider, 4a...Heart-shaped cam, 5...Movable contact piece, 6...Base member, 6a...Protrusion, 7...Fixed contact piece , 8...Bracket, 9...Fixing member, 1
0...Return spring, 12...Knob.

Claims (1)

[Scope of utility model registration request] It has a slider to which a movable contact piece is fixed, a casing that slidably supports the slider, and a fixed contact piece implanted in the casing, and the slider is provided with a heart-shaped cam, and the slider is provided with a heart-shaped cam. A U-shaped member is provided, one end of the U-shaped member is rotatably supported with respect to the housing, and the other end of the U-shaped member is engaged with a heart-shaped cam. A U-shaped leaf spring that presses the U-shaped leaf spring toward the heart-shaped cam is provided, a housing portion for the U-shaped leaf spring is provided in the housing, and a center curved lower part of the U-shaped leaf spring is provided on the inner wall of the housing portion. A protrusion is provided to support the side, and R-shaped protrusions are formed at both ends of the U-shaped leaf spring, respectively, and extend laterally,
The push button switch is positioned by bringing one R-shaped projection into contact with the U-shaped member and engaging the other R-shaped projection into an engagement hole provided in the wall of the storage portion. A hook-shaped protrusion is provided at the tip of the protrusion that supports the leaf spring, and
A push button switch characterized in that a U-shaped leaf spring is provided with a hole that engages with the hook-shaped projection.