JPH08335426A - Keyboard switch - Google Patents

Abstract

PURPOSE: To improve water-proofing performance, dust-proofing performance, electrostatic withstand voltage performance, and assembling efficiency of a keyboard switch. CONSTITUTION: In a keyboard switch, a keytop 11 is supported to be pushed down in a housing 18, and the keytop 11 is exposed on the outer surface side of the housing 18. In this keyboard switch, a cylindrical support part 15 is fixed to an inner surface of the housing 18, a skirt-shaped resilient member 14 for restoration is fixed on an inner circumference of the support part 15, the support part 15 and the resilient member 14 for restoration form a recessed keytop installation part 19 on the outer surface side of the housing 18, and the keytop 11 is fixed by the resilient member 14 for restoration to be disposed on the keytop installation part 19.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a keyboard switch mainly used as a control panel for office automation equipment, mobile phones and the like.

[0002]

2. Description of the Related Art Conventionally, this kind of keyboard switch is
As shown in FIGS. 4 and 5, the key tops 1 and 6 arranged on the printed circuit board 40 in the housing 8 are projected to the outer surface side of the housing 8 through the window holes 9 formed in the housing 8 (surface plate). As a result, the key tops 1 and 6 can be pressed against the printed circuit board 40 to perform the switch operation.

In the example of FIG. 4, the back surface of the key top 1 has a skirt shape (a thin-walled taper tube shape that expands in the back direction).
The elastic member 4 for return is fixed, and a flat plate-shaped support portion 5 is fixed to the expanded side edge of the elastic member 4 for return. By fixing the support portion 5 to the printed circuit board 40, the key top 1 Are supported on the printed circuit board 40 so that they can be pressed down and returned. Then, on the back surface side of the key top 1, facing the fixed contacts 42 and 43 on the printed circuit board 40, the moving contact 2
Is stuck.

Further, in the example of FIG. 5, the tact switch 4 having a convex portion 47 for switch operation which can be restored by pressing.
6 is fixed on the printed circuit board 40, and the key top 6 is
It is loaded on the tact switch 46. The convex portion 7 is fixed to the back surface of the key top 6 so as to face the convex portion 47 of the tact switch 46.

[0005]

As described above, in the conventional keyboard switch, the key tops 1 and 6 are the printed circuit board 4
Since the key tops 1 and 6 and the housing 8 (surface plate) are supported on the 0 side and have a separate structure, the inside of the housing 8 is inserted through the gap between the window hole 9 of the housing 8 and the key tops 1 and 6. There is a problem in waterproof performance, dustproof performance, and electrostatic withstand voltage performance that water, dust, and static electricity enter the printed circuit board 40 side. Further, there are many parts and there is a problem in assembly.

The present invention has been made in view of such conventional problems.
It is intended to provide a keyboard switch having high waterproof performance, dustproof performance, electrostatic withstand voltage performance, and good assembly efficiency.

[0007]

The features of the present invention for solving the above-mentioned conventional problems and achieving the intended purpose are as follows.
In a keyboard switch in which a key top is supported in a housing so that it can be pushed down, and the key top is exposed to the outer surface side of the housing, a cylindrical support portion is fixed to the inner surface of the housing, and the inner circumference of the support portion is fixed. A skirt-shaped return elastic member is fixed to the skirt, and a concave key top mounting portion is formed on the outer surface side of the housing with the support portion and the return elastic member, and the key top is fixed to the return elastic member. , The key top mounting portion.

The housing, the supporting portion, the elastic member for return and the key top are integrally molded, and the housing is made of a material having a relatively high rigidity such as ABS or a composite resin of ABS and an elastomer. It is preferable that the restoring elastic material is formed of a material having a relatively large elasticity such as an elastomer or silicon rubber.

[0009]

According to the present invention, by fixing the key top to the skirt-shaped elastic member for returning, the key top is supported so as to be able to be pressed down and returned, and the elastic member for returning is held on the inner circumference of the cylindrical supporting portion. By fixing the support to the inner surface of the housing, the key top is supported on the housing side, the key top and the housing are integrated, moisture,
There is no gap for dust and static electricity to enter. At this time, a concave key top mounting portion is formed on the outer surface side of the housing by the support portion and the elastic member for returning, and the key top is arranged in this key top mounting portion, and the key top is exposed to the outer surface side of the housing.

Further, by forming the housing with a material having a large rigidity such as ABS or a composite resin of ABS and elastomer, a printed circuit board or the like can be suitably accommodated in the housing, and the elastic member for restoration can be elastomer, silicone rubber or the like. By forming the key top with a material having a large elasticity, the key top is favorably supported so as to be able to be pushed back.
Then, by integrally molding the housing, the support portion, the elastic member for return and the key top, the number of parts is reduced and the assembly process is simplified.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to FIGS.

FIG. 1 shows a first embodiment of the present invention.
In the figure, 11 is a key top, 14 is a return elastic material,
Reference numeral 15 is a support portion, and 18 is a housing, which are integrally molded with two kinds of materials. That is, the parts of the key top 11 and the elastic member 14 for returning are made of elastomer, silicone rubber or the like in order to increase elasticity and flexibility and to give a click feeling, and the part of the housing 18 increases rigidity. Therefore, a thermoplastic resin, for example,
ABS (acrylonitrile, butadiene, styrene),
It is formed of a composite resin of ABS and elastomer. The supporting portion 15 is a boundary between these two kinds of materials.

On the back surface of the key top 11, a restoring elastic material 1 is provided.
4 is fixed, the return elastic member 14 is formed in a skirt shape (a thin taper cylinder shape that expands in the back direction), and the expansion side edge is fixed to the inner circumference of the cylindrical support portion 15. There is. It should be noted that the elastic member 14 for return and the supporting portion 15 may be cylindrical or square tubular as long as they are tapered tubular or tubular. The support portion 15 includes the key top 11 and the elastic member 1 for returning.
It surrounds 4 and is fixed to the inner surface of the housing 18 (surface plate). The return elastic member 14 and the support portion 15 form a concave keytop mounting portion 19 on the outer surface side of the housing 18, and the keytop 11 is disposed in the keytop mounting portion 19 and It is projected (exposed) to the outer surface side. The bottom surface of the support portion 15 is in contact with the surface of the printed circuit board 40 inside the housing 18.

A moving contact 12 is fixed to the back surface of the key top 11 by printing a conductive paste, and the key top 11, the restoring elastic member 14 and the supporting portion 15 are provided on the moving contact 12. Are arranged so as to face the fixed contacts 42 and 43 on the printed circuit board 40.

In the keyboard switch thus constructed, when the key top 11 is pressed with a finger, the return elastic member 14 is deformed so that the moving contact 12 of the key top 11 contacts the fixed contacts 42 and 43 of the printed circuit board 40. When the key top 11 is released, the return elastic member 14 is restored and the moving contact 1
The switch operation is performed so that 2 is separated from the fixed contacts 42 and 43 and is disconnected. Since the key top 11 is integrally molded with the return elastic member 14, the support portion 15, and the housing 18, the key top 11 and the housing 18 are formed.
Since there is no gap between them, the waterproof performance, dustproof performance, and electrostatic withstanding performance are improved, and the number of parts is small and the assembly efficiency is improved.

FIG. 2 shows a second embodiment of the present invention,
In the figure, 16 is a key top. Key top 16
The convex portion 17 is fixed to the back surface of the key top 1
6, the elastic member 14 for returning and the supporting portion 15 are
Of the tact switch 4 fixed on the printed circuit board 40.
It is arranged so as to face the convex portion 47 for switch operation which can be restored by pressing down. The same parts as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted. Also,
The key top 16 has a protrusion 17 and a moving contact 12,
It is similar to the key top 11.

Therefore, the switch operation is performed so that the convex portion 47 of the tact switch 46 is pushed and returned via the convex portion 17 by pushing or releasing the key top 16 with a finger. Since the key top 16 is integrally formed with the return elastic material 14, the support portion 15, and the housing 18, there is no gap between the key top 16 and the housing 18, and the waterproof performance, dustproof performance, and electrostatic withstand voltage are maintained. The performance is improved, the number of parts is small, and the assembling efficiency is improved.

FIG. 3 shows a third embodiment of the present invention.
The key top 16, the elastic member 14 for return, and the support portion 15 are
The convex portion 17 on the back surface of the key top 16 is located above the contact point 49 on the front surface of the printed circuit board 40 facing each other and the contact point 59 on the back surface of the membrane switch sheet 50 adhered with a gap therebetween via the spacer 60. It is arranged to match with. The same parts as those in the first and second embodiments are designated by the same reference numerals, and the description thereof will be omitted.

Therefore, by pressing or releasing the key top 16 with a finger, the membrane switch sheet 50 is deformed and restored through the convex portion 17 to make contact points 49, 59.
A switch operation is performed so that the connection and disconnection are established.
Since the key top 16 is integrally molded with the return elastic material 14, the support portion 15, and the housing 18,
Since there is no gap between the key top 16 and the housing 18, the waterproof performance, the dustproof performance, and the electrostatic withstanding performance are improved, and the number of parts is small and the assembly efficiency is improved.

In the third embodiment, the cap 20 is mounted on the front surface side of the key top 16, but the key top 1 is similarly applied to the first and second embodiments.
Caps may be attached to 1,16.

[0021]

As described above, in the keyboard switch according to the present invention, the tubular support portion is fixed to the inner surface of the housing, and the skirt-like elastic member for returning is fixed to the inner surface of the support portion to support the support portion. And by forming a concave key top mounting part on the outer surface side of the housing with the elastic material for return, and fixing the key top to the elastic material for return and disposing on the key top mounting part, the key top and the housing are integrated. , Waterproof performance, dustproof performance, electrostatic withstand voltage performance, etc. are improved. Also,
It is possible to integrally mold the housing, the support portion, the elastic material for return, and the key top.

Further, the housing is made of a material having a large rigidity such as ABS or a composite resin of ABS and an elastomer, and the elastic material for restoration is formed of a material having a large elasticity such as an elastomer or silicon rubber. By integrally molding the elastic material for return and the key top, the number of parts is reduced and the assembling efficiency is improved.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of a keyboard switch according to the present invention.

FIG. 2 is a sectional view showing a second embodiment of the keyboard switch according to the present invention.

FIG. 3 is a sectional view showing a third embodiment of the keyboard switch according to the present invention.

FIG. 4 is a sectional view showing an example of a conventional keyboard switch.

FIG. 5 is a sectional view showing another example of a conventional keyboard switch.

[Explanation of symbols]

 11 Key Top 12 Moving Contact 14 Elastic Material for Returning 15 Supporting Part 16 Key Top 17 Convex Part 18 Housing 19 Key Top Mounting Part 20 Cap 40 Printed Circuit Board 42, 43 Fixed Contact 46 Tact Switch 47 Convex Part 49 Contact Point 50 Membrane Switch Sheet 59 Contact 60 Spacer

Claims (3)

[Claims] 1. A keyboard switch in which a key top is supported in a housing so as to be able to be pushed down and the key top is exposed to the outer surface side of the housing, wherein a cylindrical support portion is fixed to the inner surface of the housing, A skirt-shaped elastic member for returning is fixed to the inner periphery of the supporting portion, and the supporting portion and the elastic member for returning form a concave key top mounting portion on the outer surface side of the housing, and the key top is for the returning operation. A keyboard switch fixed to an elastic material and arranged in the key top mounting portion. 2. The housing, the support portion, the elastic member for returning and the key top are integrally molded, and the housing is made of a material having relatively large rigidity, and the elastic member for returning has relatively large elasticity. The keyboard switch according to claim 1, wherein the keyboard switch is formed of a material. 3. The keyboard switch according to claim 2, wherein the housing is made of ABS or a composite resin of ABS and an elastomer, and the restoring elastic member is made of an elastomer or silicone rubber.