JPH0635310Y2 - Push button switch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a push button switch used for various input devices such as a computer and a word processor.

[Prior Art] A push button switch used for the above-mentioned applications is required to have a small operation sound when operated, and as a push button switch having such conventional soundproofing measures, it is practically used.
There is one shown in Japanese Patent No. 1.

7 to 10 are drawings described in the above publication,
The figure is a front view showing the stem, FIG. 8 is a cross-sectional view of the push button switch, FIG. 9 is a cross-sectional view taken along the line II of FIG. 8, and FIG. 10 is a bottom view with the lower case and the key top removed. Is.

As shown in FIG. 7, the push button switch shown in the above publication is
A cushioning member 14 composed of a pair of O-shaped rubber rings is attached to the shoulder portion 4a of the stem 4, and the stem 4 is fixed by a spring 6 interposed between the stem 4 and the lower case 1 as shown in FIG. The rubber ring 14 is elastically pressed upward, and the upper end of the rubber ring 14 is in contact with the upper inner wall of the upper case 2.

When the key-top 5 is pressed downward against the elasticity of the spring 6 from such a state, the stem 4 also moves downward, and in FIG. 8, the leaf spring 11 for pressing the switch element and the leaf spring 12 for feeling the click are formed. Pushed by the lower end of the stem 4, the protrusion 11c of the leaf spring 11 presses the movable contact piece (not shown) toward the fixed contact piece side so that both contact pieces come into contact with each other and the contact of the switch is turned ON. Rides over the circular arc portion 12b of the leaf spring 12 and produces a click feeling.

Then, at this time, the lower end of the cushioning member 14 abuts on the projections 1a, 1b on the inner bottom wall of the lower case 1. Further, when the pressing of the key top 5 is released, the stem 4 returns to the original state by the elastic force of the spring 6, the contact of the switch is turned off, and the upper end of the buffer member 14 is the upper inner wall of the upper case 2. Abut.

[Problems to be solved by the device]

However, as described above, the push button switch is
Since the cushioning member 14 formed of a V-shaped rubber ring is provided on the stem 4, a large amount of rubber member material is required, resulting in cost up. Further, the downward movement of the stem 4 causes the lower end of the rubber ring 14 to fall inside the lower case 1. Since it is configured to contact the protrusions 1a, 1b on the bottom wall, if the pressing operation of the key-top 5 is repeated many times, the rubber ring 14 may be cracked and cut, and in this case, the feeling is deteriorated. .

Furthermore, there is a problem that the aging of the rubber ring 14 weakens the attachment strength (adhesion) and makes it easier to come off from the stem 4.

The present invention is intended to solve the above problems, and an object of the present invention is to reduce the cost of the cushioning member as compared with the conventional one, and to maintain a good pressing feeling for a long time as compared with the conventional one.
Moreover, it is an object of the present invention to provide a push button switch in which there is no concern that the cushioning member will come off from the stem.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the present invention has a case, a stem slidably provided in the case, and a cushioning member that absorbs impact sound between the stem and the case when the stem moves. In the push button switch, the cushioning member is
It consists of a dumbbell-shaped body that connects wide circular heads at both ends with a narrow width portion, and a fitting groove for fitting the cushioning member is provided on both sides of the shoulder portion of the stem, and the cushioning groove is provided in the fitting groove. A protrusion is provided for holding the narrow width portion of the buffer member when the member is fitted in the fitting groove.

[Action]

As described above, the buffer member is fitted in the fitting grooves provided on both sides of the shoulder portion of the stem, and the buffer member is brought into contact with the upper bottom wall and the lower bottom wall of the case. The shock absorbing sound can be absorbed by the cushioning member at the time of pressing or at the time of returning.

Further, the cushioning member is dumbbell-shaped, and the rubber member is less than that of the conventional O-ring type, and the cost can be reduced.

Further, since the projection is provided in the fitting groove of the cushioning member and the narrow portion of the dumbbell-shaped cushioning member is held, even if a crack is formed below the cushioning member, the cushioning member will be cut off. There is no problem, and even if the rubber member constituting the cushioning member is aged, the rubber member will fit into the fitting groove for a long period of time, and will not come off.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a sectional view of an essential part showing a mounting state of a cushioning member of a push button switch according to the present invention, and FIG. 2 is a perspective view of a stem only,
FIG. 3 is a front view of a stem fitted with a cushioning member, FIG. 4 is a side view of the same, FIG. 5 is an enlarged perspective view of the cushioning member, and FIG. 6 is a sectional view taken along line II-II in FIG. .

The same parts as those of the conventional example shown in FIGS. 7 to 10 are designated by the same reference numerals, and the duplicated description will be omitted.

The difference between the present invention and the conventional example lies in the shape of the cushioning member and the mounting structure thereof, so this point will be mainly described below.

In FIG. 5, reference numeral 20 is a cushioning member made of a dumbbell-shaped flat plate in which wide circular head portions 21 and 22 at both ends are connected by a narrow portion 23, and is made of a rubber member.

Further, as shown in FIGS. 1 and 2, fitting grooves 24, 25 of the cushioning member 20 are formed on both sides of the shoulder 4a of the stem 4,
Protruding portions 26, 27 for holding the narrow width portion 23 of the buffer member 20 are formed opposite to each other in the central portions of the grooves 24, 25.

When the pair of cushioning members 20 are fitted into the fitting grooves 24, 25, the narrow portion 23 at the center of the cushioning member 20 is held by the protrusions 26, 27 as shown in FIG. The circular heads 21 and 22 at both ends project outward from the upper and lower ends of the shoulder 4a.

As shown in FIG. 1, the key top 5 is attached to the tip of the stem 4 by tightly fitting the central portion 5a between the protrusions of the hole 4b of the stem 4.

Next, the operation of the push button switch will be described.

FIG. 1 shows a stationary state before pressing the key top 5, in which state the stem 4 is elastically pressed upward by a spring 6,
The upper circular head 21 is in contact with the upper inner wall of the upper case 2, and the contact of the switch is kept in the OFF state.

When the key-top 5 is pressed downward against the elasticity of the spring 6 from this state, the stem 4 also moves downward, and the contact of the switch is turned ON with a click feeling as in the conventional switch. At this time, the circular head 22 below the cushioning member 20 contacts the protrusions 1a and 1b on the lower inner wall of the lower case 1.

Further, when the pressing of the key top 5 is released, the stem 4 returns to the original state by the elastic force of the spring 6, and the contact of the switch is turned off at this time, and the circular head 2 above the buffer member 14 is turned off.
1 contacts the upper inner wall of the upper case 2.

In the above-described embodiment having the above-described structure, the circular heads 21 and 22 of the cushioning member 20 fitted to the stem 4 as the stem 4 moves up and down have the inner walls of the upper case 2 and the lower case 1. Since it abuts against, it is possible to absorb the impact sound generated when the stem 4 is pressed or returned.

Further, the cushion member 20 is attached to the stem 4 by fitting the fitting grooves 24, 2
It is only necessary to fit into 5 and hold the narrow width part 23 with the projections 26 and 27, and it can be installed without the need for adhesives, etc., the installation work is easy, and the rubber member ages after installation. However, they are fixed in the fitting grooves 24, 25 over a long period of time. In addition, even if the rubber member ages after mounting, it will continue for a long time and the mating grooves 24, 2
Fitted in 5, it absorbs impact noise over a long period of time.

Further, since the cushioning member 20 formed of a dumbbell-shaped flat plate requires less rubber material than the conventional O-ring type, the cost is reduced.

Furthermore, even if a crack is generated in the circular head portion 21 below the cushioning member 20 when the stem 4 is moved downward, the cushioning member 20 itself is not broken.

[Effect of device]

According to the present invention, as described above, the shock noise can be absorbed when the stem is moved up and down, and the shock absorbing member of the present invention is lower in cost than the conventional one and can be used for a long time. Even so, the cushioning member does not break due to the occurrence of cracks as in the past, and even when the rubber member ages,
Since it does not come off from the fitting groove, it is possible to absorb the impact sound of the stem over a long period of time.

[Brief description of drawings]

1 to 6 are explanatory views of an embodiment of the present invention.
The figure is a cross-sectional view of the main part showing the mounting state of the cushioning member of the push button switch. Fig. 2 is a perspective view of the stem only. Fig. 3 is a front view of the stem fitted with the cushioning member. FIG. 5 is an enlarged perspective view of the cushioning member, FIG. 6 is a sectional view taken along line II-II of FIG. 3, FIGS. 7 to 10 are explanatory views of a conventional example, and FIG. 7 shows a stem. FIG. 8 is a sectional view of the push button switch, FIG. 9 is a sectional view taken along line II of FIG. 8, and FIG. 10 is a bottom view of the lower case with the key top removed. 1,2 …… Case, 4 …… Stem, 4a …… Shoulder, 20 …… Cushioning member, 21,22 …… Circular head of cushioning member, 23 …… Narrow width part, 24,25
…… Mating groove, 26,27 …… Projection.

Claims (1)

[Scope of utility model registration request] 1. A push button switch having a case, a stem slidably provided in the case, and a cushioning member for absorbing an impact sound of the stem and the case when the stem is moved. A dumbbell-shaped body that connects wide circular heads with a narrow width portion is provided with fitting grooves for fitting the cushioning member on both sides of the shoulder portion of the stem, and the cushioning member is provided in the fitting groove. A push-button switch comprising a protrusion that holds the narrow portion of the cushioning member when fitted in the fitting groove.