JP2001229764A - Key switch structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stabilize the electrical contact position of a key switch by preventing the float of a housing from a base plate. SOLUTION: In the structure, a housing 5 is formed for each key, and plural fixing pins 5f are formed in the housing 5 to enclose the movable contact and fixed contact. A base plate 7 has plural attaching holes 7b and recesses 7c corresponding to the fixing pins 5f. The fixing pins 5f are forced into the attaching holes 7b, and the tip of each fixing pin 5f is deformed by heating. The deformed part 5g of each fixing pin is stored in the recess 7c, and the attaching holes 7b are closed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a key switch structure used for an input device of an information processing apparatus, and more particularly to a key switch structure used for a keyboard of a portable personal computer, a word processor, or the like, which is required to be thin.

[0002]

FIG. 12 is a sectional view showing a conventional key switch structure, and FIG. 13 is an exploded perspective view. The key switch structure includes a key top 21, a first link member 22, a second link member 23, an elastic member 24, a housing 25, a membrane contact sheet 26, a base plate 27, and a screw 2
8.

The key link 21 has a first link member 22
Support portions 21a and 21b for rotatably supporting one end of the motor
And a slide support portion 2 that supports one end of the second link member 23 rotatably and so as to be able to translate (move) horizontally.
1c and 21d are provided. The first link member 22 has a pair of legs 22a, 22b.
b, one end of the rotation support portions 21a, 21
b are connected to the legs 22a and 22b.
And the legs 22a, 22b
At the other end, a second connecting rod 22d is provided so as to connect the legs 22a and 22b.

Further, each of the legs 22a and 22b is located on a line connecting the first connecting rod 22c and the second connecting rod 22d and at the same distance from the connecting rods 22c and 22d. Are provided with shafts 22e and 22f.
The second link member 23 has a pair of legs 23a and 23b. One end of each of the legs 23a and 23b is rotatable by the slide support portions 21c and 21d of the key top 21 and is horizontally translated (moved). First support projection 2 supported so as to be able to be supported
3c and 23d have a second support protrusion 23 at the other end thereof at a distance equal to the distance between both connecting rods 22c and 22d of the first link member 22.
e and 23f are provided respectively.

The first support projections 23c and 23d and the second
Shaft holes 23g and 23h are provided on a line connecting the support protrusions 23e and 23f and at the same distance from the respective support protrusions 23c and 23d; 23e and 23f. Further, the legs 23a and 23b are each
It is connected by a connecting portion 23i on the distal end side from 3c and 23d.

A first link member 22 and a second link member 23
Are rotatably engaged by fitting the rotation shafts 22e and 22f of the first link member 22 into the rotation holes 23g and 23h of the second link member 23. The elastic member 24 is formed in a substantially cup shape using rubber or the like as a material, and has a contact pressing portion 24 a protrudingly formed at the center of the inner surface. The elastic member 24 has a membrane so that its upper part is in contact with the back surface of the key top 21. It is arranged on the contact sheet 26.

The housing 25 has a plurality of holes corresponding to the plurality of keys, and the first link member 2 is provided near one end of the hole.
Slide guide 25 for supporting the second second connecting rod 22d so as to be rotatable and parallelly movable (movable) in the horizontal direction.
In the vicinity of the other end of the hole, rotation guides 25c and 25d for rotatably supporting the second support protrusions 23e and 23f of the second link member 23 are provided.

At both ends of the hole of the housing 25, arcuate guide walls 25e for fixing the elastic member 24 are provided so as to face each other. Further, screw holes 25f for fixing the membrane contact sheet 26 and the base plate 27 are provided. Is provided. The membrane contact sheet 26 includes two flexible sheets 26a and 26b, and the two flexible sheets 26a and 26b.
a, a spacer sheet 26c sandwiched between 26b,
The spacer sheet 26c has a plurality of through holes 26f.

The through hole 26f is formed by two flexible sheets 2
A fixed contact 26d is provided on the flexible sheet 26b on the base plate 27 side, and a fixed contact 26d is provided on the flexible sheet 26a on the elastic member 24 side so that a space is formed between the flexible sheets 26a and 26b. Are provided with movable contacts 26e, respectively. The base plate 27 is disposed at a lower portion so as to mount the above-described components. The membrane contact sheet 26 is sandwiched between the housing 25 and the base plate 27, and the screws 28 passed from the base plate 27 are fastened to the screw holes 25f of the housing 25. Assembled with

In this configuration, the screw 28 and the screw hole 25
f is provided at a ratio of one to several keys. FIG. 14 is a sectional view showing the operation of the above-described configuration. First,
As the key top 21 is depressed by a finger or the like and moves downward, the first link member 22 is connected to the first connecting rod 2 rotatably supported by the rotation support portions 21a and 21b of the key top 21.
2c rotates clockwise around the center of rotation, and a second connecting rod 22 provided at the other end of the first link member 22.
d is a slide guide 25a, 25b of the housing 25.
Slidably in the horizontal direction.

The second link member 23 has shaft holes 23g and 23h.
Since the shafts 22e and 22f of the first link member 22 are rotatably fitted to the first link member 22, the first support projections 23c and 23d of the second link member 23 The slide guide 2 is horizontally slid along the slide support portions 21c and 21d, and the rotation guide 2 of the housing 25 is provided.
Second support protrusion 23 rotatably supported by 5c and 25d
The second link member 23 rotates counterclockwise around e and 23f as the center of rotation.

As a result, the key top 21 is
5 while maintaining the parallelism with respect to 5, the lower surface of the key top 21 presses the upper part of the elastic member 24 with the downward movement of the key top 21.
Reference numeral 4 denotes a member which is compressed and deformed, and a contact pressing portion 24a formed inside the elastic member 24 and protruding downward contacts and presses the flexible sheet 26a of the membrane contact sheet 26.

As a result, as shown in FIG. 14A, the movable contact 26e comes into contact with the fixed contact 26d to be electrically connected, and the switch is closed. Furthermore, key top 2
When 1 is pressed, the connecting portion 23i of the second link member 23 is provided on the end side with respect to the first support protrusions 23c and 23d, so that the first link member 22 and the second link member 23 do not overlap. , Both rotate to a position that is horizontal with respect to the housing 25.

When the key top 21 is released, each component returns to its original state by the restoring force of the elastic member 24 as shown in FIG.
The movable contact 26e of FIG. 6 is separated from the fixed contact 26d, and the electrical contact is cut off, so that the switch is opened.

[0015]

However, in the above-mentioned conventional technique, the housing is formed thin as a common part for each key by integral molding, and the housing is fixed to the base plate with few screws. There is a problem that the missing portion rises from the base plate, and as a result, the overall height of the key switch becomes uneven and the electrical connection position of the key switch becomes unstable.

In general, it is necessary to lower the overall height of the key switch and reduce its weight as a keyboard for an easily portable device. However, in the conventional structure, it is necessary to reduce the size of the key top. There is also a problem that it is impossible to reduce the mass, and there is also a problem that the degree of freedom of the key arrangement is limited because the housing is integrally formed as a common component for each key as described above. .

Therefore, according to the present invention, the electrical connection position of the key switch can be stabilized by preventing the housing from floating from the base plate, and the key top can be reduced in size and weight, and the key arrangement can be achieved. It is an object to realize a key switch structure having a large degree of freedom.

[0018]

SUMMARY OF THE INVENTION Therefore, the present invention is directed to a movable contact by pressing and depressing a keytop by sandwiching a membrane sheet having a movable contact and a fixed contact between a housing supporting the keytop so as to be depressable and a base plate. In a key switch structure in which a switch is closed by contacting the fixed contact with a fixed contact, a housing is formed for each key, and a plurality of fixed pins are formed in the housing so as to surround the movable contact and the fixed contact. Is characterized in that a plurality of mounting holes corresponding to the fixing pins are provided, and the housing is fixed to the base plate together with the membrane sheet by press-fitting the fixing pins into these mounting holes.

[0019]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a key switch structure according to an embodiment of the present invention. FIG. 1 is a sectional view showing the first embodiment, and FIG. 2 is an exploded perspective view showing the first embodiment.

The key switch structure according to the present embodiment includes a key top 1, a first link member 2, a second link member 3, an elastic member 4, a housing 5, a membrane contact sheet 6, and a base plate 7. Key top 1
In the same manner as in the prior art, the rotation support portions 1a and 1b rotatably support one end of the first link member 2 and the one end of the second link member 3 are rotatably and horizontally translated (moved). Slide support portions 1c and 1d are provided so as to be able to support them.

The first link member 2 also has a pair of legs 2a and 2b, similar to the conventional link member, and one end of the legs 2a and 2b is inserted into and supported by the rotation support portions 1a and 1b of the key top 1. A first connecting rod 2c is provided so as to connect the legs 2a and 2b. Similarly, a second connecting rod 2d is connected to the other end of the legs 2a and 2b so as to connect the legs 2a and 2b. Further, on the outer surface of each of the legs 2a, 2b, there is a line connecting the first connecting rod 2c and the second connecting rod 2d, and for each of the connecting rods 2c, 2d. The shafts 2e and 2f are provided at positions corresponding to the distance.

The second link member 3 has a pair of legs 3a, 3b.
The first support protrusions 3c, 3 are rotatably supported by the slide support portions 1c, 1d of the key top 1 and are capable of parallel translation (movement) in the horizontal direction at one ends of the legs 3a, 3b.
d is provided toward the outside, and the first link member 2 is provided at the other end.
Of the second support projection 3 at a distance equal to the distance between
e, 3f are provided inward.

The shaft hole 3g is located on a line connecting the first support projections 3c, 3d and the second support projections 3e, 3f and at the same distance from each of the support projections 3c, 3d; 3e, 3f. , 3h. Further, the legs 3a, 3
b is connected by a connecting portion 3i on the tip side from the first support protrusions 3c and 3d.

The elastic member 4 is also formed in a substantially cup-like shape using rubber or the like as a conventional one, and a contact pressing part 4a is formed to project from the center of the inner surface. The housing 5 is divided into one key unit and formed in a frame shape. The housing 5 supports the second connecting rod 2d of the first link member 2 near one end thereof so as to be rotatable and horizontally movable (movable) in a horizontal direction. A slide guide 5a is provided, and rotation guides 5c and 5d for rotatably supporting the second support protrusions 3e and 3f of the second link member 3 are provided near the other end.

An arc-shaped guide wall 5e for fixing the outer periphery of the elastic member 4 is provided at the center of both ends of the housing 5 so as to face each other. A plurality of fixing pins 5f having a predetermined length are formed so as to surround the hole 6f. The membrane contact sheet 6 includes two flexible sheets 6a and 6b.
And a spacer sheet 6c sandwiched between the two flexible sheets 6a and 6b. The spacer sheet 6c has a plurality of through holes 6f corresponding to a plurality of keys.

The through hole 6f is provided with two flexible sheets 6
A fixed contact 6d is formed on the flexible sheet 6b on the base plate 7 side, and a fixed contact 6d is formed on the flexible sheet 6a on the elastic member 4 side such that a space is formed between the flexible sheet 6a and the flexible plate 6b so as to be located in the space. The movable contact 6e is provided, and a plurality of through holes 6g are provided in the membrane contact sheet 6 so as to be located around each through hole 6f.

The base plate 7 is disposed at a lower portion so as to mount each of the above components.
A spacer projection 7a having a thickness equivalent to that of the membrane contact sheet 6 corresponding to the through hole 6g of the membrane contact sheet 6;
A mounting hole 7b for passing the fixing pin 5f of the housing 5 is provided at the center of each spacer protrusion 7a so as to penetrate therethrough. Further, a concave portion (about the periphery of each mounting hole 7b on the lower surface side of the base plate 7) is provided. Counterbore) 7c
Are formed.

In this configuration, each component is assembled as follows. The shafts 2e and 2f of the first link member 2 are
By fitting the shaft holes 3g and 3h of the link member 3,
The first link member 2 and the second link member 3 are rotatably combined in an X-shape, and the first link 2c of the first link member 2
Is inserted into the rotation support portions 1a, 1b of the key top 1, and the first support projections 3c, 3d of the second link member 3 are rotatably and horizontally translated in the slide support portions 1c, 1d of the key top 1. (Exercise) Insert as possible.

On the other hand, the membrane contact sheet 6 is placed on the base plate 7, and each spacer projection 16a of the base plate 7 is passed through the through hole 6g of the membrane contact sheet 6, and the housing 5 is fixed from above into the mounting hole 6b of each spacer projection 6a. Press in the pin 5f. Then, the tip of the fixing pin 5f protruding from the lower surface side of the base plate 7 is deformed into a flat shape by heating as shown in FIG. 1, thereby fixing the housing 5 together with the membrane contact sheet 6 on the base plate 7, thereby fixing the fixing pin. The deformed portion 5g of 5f is housed in the recess 6c of the base plate 7 and
c to close the mounting hole 6b.

Further, the lower portion of the elastic member 4 is fitted inside the guide wall 5e and fixed on the membrane contact sheet 6,
The key top 1 is put on from above, the second connecting rod 2d of the first link member 2 is inserted into the slide guide 5a of the housing 5, and the second support projection 3 of the second link member 3 is inserted.
e, 3f are inserted into the rotation guides 5c, 5d of the housing 5.

The switch operation of the first embodiment having the above-described configuration is the same as that of the conventional switch, and the description thereof is omitted. However, the housing 5 is formed in units of one key, and
Since each housing 5 is fixed to the base plate 7 at a plurality of positions by a plurality of fixing pins 5f, the housing 5 does not rise from the base plate 7, and the height of each key switch becomes uniform. The stable connection position becomes stable.

The fixing pin 5f has its tip deformed into a flat shape by heating, so that the housing 5 is fixed on the base plate 7 together with the membrane contact sheet 6, whereby the deformed portion 5g of the fixing pin 5f is fixed to the base plate 7. Since the device is housed in the concave portion 6c, the apparatus can be configured to be thin, and the deformed portion 5g is welded to the concave portion 6c to form the mounting hole 6c.
Since b is closed, drip-proof property is also obtained.

Further, the second support projection 3 of the second link member 3
Since e and 3f are provided facing inward, the key top 1
Can be reduced in size, thereby reducing the overall mass and weight, thereby improving the convenience of transportation. FIG.
FIG. 4 is a sectional view showing a second embodiment. In the second embodiment, the structure of the membrane contact sheet 6 is changed.

That is, in the present embodiment, the membrane contact sheet 6 is composed of two flexible sheets 6a and 6b and a spacer 6h sandwiched between the two flexible sheets 6a and 6b as shown in the figure. The spacer 6h is formed by resist printing and has elasticity. The portion where the spacer 6h is provided is a portion corresponding to the slide guide 5a and the rotation guides 5c and 5d of the housing 5, and accordingly, the second connecting rod 2d of the first link member 2 rotatably supported by the slide guide 5a is connected to the spacer 6h. At this position, it contacts the membrane contact sheet 6 and rotates and translates horizontally.

Of course, the second support projections 3e, 3f of the second link member 3 rotatably supported by the rotation guides 5c, 5d.
Also contacts the membrane contact sheet 6 at the position of the spacer 6h and rotates. Other configurations are the same as in the first embodiment, and the switching operation is performed in the same manner.

The second embodiment as described above is similar to the first embodiment.
In addition to the same effects as the embodiment, the second connecting rod 2d of the first link member and the second support projections 3e and 3f of the second link member 3 are formed by a membrane contact sandwiching an elastic spacer 6h. Since the membrane contact sheet 6 comes into contact with the sheet 6 and rotates and translates in the horizontal direction, the thickness of the membrane contact sheet 6 becomes uniform and the key top 1 can be suppressed in parallel.

Further, the height of the entire key can be reduced while securing the rigidity of the link member, and a portion of the spacer having elasticity serves as a support portion, and a gap due to a manufacturing error between the housing and the link member is reduced. Since the components can be absorbed, the swinging motion of the components can be reduced, and the operating noise can be suppressed. FIG. 4 is a cross-sectional view showing the third embodiment.

In the third embodiment, the housing 5 is provided with a slope 1 formed in a skirt shape on the entire peripheral surface of the key top 1.
The key top 1 and the housing 5 have the same structure as that of the first embodiment or the second embodiment. Other configurations are the same as those in the first embodiment or the second embodiment.

In the third embodiment having such a configuration, the outer periphery of the housing 5, the slide guide 5a and the rotation guide
c and 5d do not hit the key top 1, and the first and second link members 2 and 3 interfere with the key top 1 at the lower end of the descending range of the key top 1, and the movement of the key top 1 is stopped.

Therefore, according to the third embodiment,
In addition to the effects of the first embodiment or the second embodiment,
When the key top 1 is depressed, the switch characteristics are hardly affected by the inclination of the key top 1, and stable switch operation characteristics can be obtained even when the stroke length of the key top 1 is short. FIG. 5 is a sectional view showing a fourth embodiment, and FIG.
FIG. 11 is an exploded perspective view of the fourth embodiment.

FIGS. 7A and 7B are diagrams showing the structure of the first link member in the fourth embodiment, wherein FIG. 7A is a plan view, FIG. 7B is a side view, and FIG. FIGS. 8A and 8B are diagrams showing a configuration of a second link member according to the fourth embodiment, wherein FIG. 8A is a plan view, FIG. 8B is a side view, and FIG. 9A and 9B are diagrams showing a configuration of a housing according to the fourth embodiment, wherein FIG. 9A is a plan view, FIG. 9B is a side view, and FIG. 9C is an enlarged view of a main part.

FIGS. 10A and 10B show the structure of a membrane contact sheet according to the fourth embodiment. FIG. 10A is a plan view of a main part, FIG. 10B is a sectional view of the main part, and FIG. It is a fragmentary sectional view. The key switch structure of the present embodiment includes a key top 11, a first link member 12, and a second link member 1.
3, an elastic member 14, a housing 15, a membrane contact sheet 16, and a base plate 17.

As in the first embodiment, the key top 11 has rotation supporting portions 11a and 11b for rotatably supporting one end of the first link member 12, and the second link member 1
3. One end of 3 can be rotated and translated horizontally (movement)
Sliding support portions 11c and 11d are provided so as to be capable of being supported. In addition, a projection 11e that fits into a fitting hole 14a provided in the upper center of the elastic member 14 is provided at the center of the key top 11. I have.

The first link member 12 has a pair of legs 12a,
12b, and one end of each of the legs 12a, 12b is inserted into the rotation support portions 11a, 11b of the key top 11.
A connecting rod 2c is provided to connect the legs 12a, 12b. Similarly, a second connecting rod 12d is provided at the other end of the legs 12a, 12b to connect the legs 12a, 12b. .

Further, on the outside of each of the legs 12a and 12b, there is a line connecting the first connecting rod 12c and the second connecting rod 12d, and the distance between each of the connecting rods 12c and 12d is equal. The shaft holes 12e and 12f are provided at the following positions, and projections 12j and 12k are provided on the back surfaces (lower surfaces) of the legs 12a and 12b, respectively, as shown in FIG.

The second link member 13 also has a pair of legs 13a,
13b, and both ends of the legs 13a, 13b are symmetrically connected by respective connecting portions 13i, 13j. First support protrusions 13c, 13 rotatably supported by the slide support portions 11c, 11d of the key top 11 and horizontally movable (movable) on one end of the legs 13a, 13b.
d is provided symmetrically across the connecting portion 3i,
The second support protrusions 3e and 3f are provided symmetrically with the connecting portion 3j interposed therebetween at a distance equal to the distance between the connecting bars 12c and 12d of the link member 12.

The first support projections 13c and 13d and the second support projections 13e and 13e are provided on the inner surfaces of the legs 13a and 13b.
f and each of the support projections 13c,
Shafts 13g and 13h are provided at positions equidistant from 13d, 13e and 13f. Further, the legs 13a,
On the back surface (lower surface) of the projection 13b, as shown in FIG.
3n and 13o are provided symmetrically with the projections 12j and 12k of the first link member 12 about the axes 13g and 13h.

The elastic member 14 is formed in a substantially cup shape using rubber or the like as a raw material, has a fitting hole 14a at the upper center, a contact pressing portion 14b protruding at the center of the inner surface, and a wall at the lower outer periphery. A thick portion 14c is formed. Housing 1
Reference numeral 5 denotes a slide which is formed in a frame shape by being divided in units of one key, and which has at one end a rotatable and horizontally translatable (movable) second connection rod 12d of the first link member 12. A guide 15a is provided, and rotation guides 15b and 15c for rotatably supporting the second support protrusions 13e and 13f of the second link member 13 are provided near the other end, and the rotation guides 15b and 15c are provided on the rotation guides 15b and 15c. Adjacent second
Projection 15 along outer wall surfaces 13f, 13m of link member 13
f, 15 g are provided.

A ring-shaped guide wall 15d is provided inside one end of the housing 15 so as to surround the thick portion 14c of the elastic member 4 so as to surround the entire circumference thereof. A plurality of claw portions 14e for holding the thick portion 14c from above are formed at predetermined intervals, and a plurality of claw portions 14e are formed on the lower surface of the housing 15 so as to surround the spacer 16c of the membrane contact sheet 16 as shown in FIG. A fixed pin 15h of a predetermined length is formed at a location.

As shown in FIG. 10, the membrane contact sheet 16 includes flexible sheets 16a and 16b, and ring-shaped spacers 16c and 16f sandwiched between the two flexible sheets 16a and 16b. This spacer 16c, 1
6f is formed by resist printing and has elasticity. A fixed contact 16d is provided on the flexible sheet 16b inside the spacer 16c, and a movable contact 16e is provided on the flexible sheet 16a. The protrusion of the first link member 12 is provided outside the spacer 16c. 12j,
Four spacers 16f shown in FIG. 10 are provided so as to correspond to 12k and the projections 13n and 13o of the second link member 13, and a plurality of through holes 16g are provided in the membrane contact sheet 16 so as to surround these. I have.

The base plate 17 is disposed at a lower portion so as to mount each of the above components. The base plate 17 has a thickness equivalent to that of the membrane contact sheet 16 corresponding to the through holes 16g of the membrane contact sheet 16. Spacer projections 17a are formed, and each spacer projection 17a is formed.
A mounting hole 17b through which the fixing pin 15h of the housing 15 passes is provided at the center of the base plate 17, and a concave portion (counterbore) is formed around the mounting hole 17b on the lower surface side of the base plate 17.

In this configuration, each part is assembled as follows. Shaft holes 12e, 12 of the first link member 12
By fitting the shafts 3g and 3h of the second link member 3 to the first link member f, the first link member 12 and the second link member 13 are rotatably combined in an X shape.
Connect the connecting rod 2c to the rotation support portions 11a, 11 of the key top 11.
b, and the first support protrusions 13c, 13d of the second link member 13 are connected to the slide support portion 1 of the key top 11.
1c and 11d are inserted so as to be rotatable and horizontally movable (movable).

On the other hand, the membrane contact sheet 16 is placed on the base plate 17, and each spacer projection 16a of the base plate 17 is connected to the through hole 16g of the membrane contact sheet 16.
Then, the fixing pin 15h of the housing 15 is pressed into the mounting hole 16b of each spacer projection 16a from above. Then, the housing 15 is fixed on the base plate 17 together with the membrane contact sheet 16 by deforming the tip of the fixing pin 15h projecting from the lower surface side of the base plate 17 into a flat shape by heating as in the first embodiment. Thus, the deformed portion of the fixing pin 15h is accommodated in the concave portion of the base plate 17 as in the first embodiment, and is welded to the concave portion to form the mounting hole 16h.
Close b.

Further, the thick portion 14c of the elastic member 14 is fitted into the ring-shaped guide wall 15d, and the thick portion 14c is pressed down from above by a plurality of claws 15e formed on the guide wall 15d. The entire periphery of the lower portion of the member 14 is supported by the guide wall 15d and fixed on the membrane contact sheet 16, and the key top 11 is covered from above and the projection 11e is provided.
Into the fitting hole 14a of the elastic member 14, and the first
The second connecting rod 12d of the link member 12 is inserted into the slide guide 15a of the housing 15, and the second support protrusions 13e and 13f of the second link member 13 are
Into the rotation guides 15b, 15c.

Next, the operation of the above configuration will be described. First, as the key top 11 is pressed down and moved downward, the first link member 12
The first connecting rod 12c rotatably supported by the first rotation supporting portions 11a and 11b rotates clockwise about the center of rotation, and the second connecting rod provided at the other end of the first link member 12. 12d is the slide guide 1 of the housing 15.
5 slides horizontally.

The second link member 13 has the shafts 3g and 3h
Since the first link member 12 is rotatably fitted in the shaft holes 12 e and 12 f of the link member 12,
The first support protrusions 13c and 13d of the link member 23 slide horizontally along the slide support portions 11c and 11d of the key top 11, and the rotation guide 15 of the housing 15 is moved.
b, 15c, the second support projection 13 rotatably supported
The second link member 13 rotates counterclockwise about e and 13f as the center of rotation.

As a result, the key top 11 is
The key top 11 moves downward while keeping it parallel to 5, and with the downward movement of the key top 11, the back surface of the key top 11 presses the upper part of the elastic member 14 positioned and fixed by the guide wall 15d of the housing 15. Therefore, the elastic member 14 is compressed and deformed, and the contact pressing portion 14b formed inside the elastic member 14 contacts and presses the flexible sheet 26a of the membrane contact sheet 16.

As a result, the movable contact 26e becomes the fixed contact 2
The switch 6d is electrically connected by contacting the switch 6d. When the key top 21 is further depressed, the legs 12a, 12b of the first link member 12 and the legs 13a, 13b of the second link member 13 enter the inside of the housing 15, and come into horizontal contact with the membrane contact sheet 16. I do.

At this time, the leg 12 of the first link member 12
The protrusions 12j and 12k provided on the a and 12b and the protrusions 13n and 13o provided on the legs 13a and 13b of the second link member 13 are provided on the membrane contact sheet 16 as shown in FIG. The flexible sheet 26a enters the inside of the ring-shaped spacer 16f while being deformed, and has a buffering effect on the key top 21 to suppress the occurrence of a tapping sound.

Note that, even when the end of the key top 11 is pressed, the outer surfaces 13k or 13m of the legs 13a, 13b of the second link member 13 are kept in contact with the projections 15f of the housing 15.
Alternatively, the first link member 12 and the second link member 13 can be smoothly operated as described above because they slide along the inner surface of 15 g. When the key top 11 is released,
Each component is composed of an elastic member 14 and a membrane contact sheet 16.
Due to the restoring force, the movable contact 16e of the membrane contact sheet 16 is separated from the fixed contact 16d, and the electrical contact is cut off, so that the switch is opened.

According to the fourth embodiment described above,
The same effects as those of the first embodiment can be obtained, and the protrusions 12j, 1 of the first link member 12 when the key top 21 is pressed down.
2k and the protrusions 13n and 13o of the second link member 13 enter the inside of the ring-shaped spacer 16f while deforming the flexible sheet 26a of the membrane contact sheet 16, thereby causing a buffering action on the key top 21. The sound can be reduced, and the protrusions 12j and 12k of the first link member 12 and the protrusions 13n and 13o of the second link member 13 are small.
The influence on the pattern design of No. 6 can be kept small.

Even when the end of the key top 11 is pressed, the outer surfaces 13 k or 13 m of the legs 13 a and 13 b of the second link member 13 are
f or 15g, the first link member 12 and the second link member 13 can operate smoothly and stably in the same manner as described above.
It is possible to reduce the tapping sound when the end of the key 1 is pressed, and to secure an operation feeling with less swinging movement.

Further, a ring-shaped guide wall 15d is formed in the housing 15, and the lower portion of the elastic member 14 is fitted inside the guide wall 15d, so that the elastic member 14 is attached to the guide wall 15d over the entire circumference. It is supported and has a structure with excellent impact resistance. FIG. 11 is a diagram showing a fifth embodiment, showing the configuration of a membrane contact sheet.
(A) is a perspective view of a main part, (b) is a cross-sectional view of the same main part,
(c) is a sectional view of a main part during operation.

In the fifth embodiment, the structure of the membrane contact sheet 16 is changed. The membrane contact sheet 16 includes two flexible sheets 16a and 16b and two flexible sheets 16a and 16b. Spacer sheet 1 sandwiched
6i. The spacer sheet 16i is provided with a plurality of through holes 16j corresponding to a plurality of keys. The through holes 16j form a space between the two flexible sheets 6a and 6b, and fixed contacts 16d are provided in the flexible sheet 16b on the base plate 17 side so as to be located in the space so as to face each other. A movable contact 16e is provided on the flexible sheet 16a on the elastic member 4 side.

The spacer sheet 16i has a through hole 1
6j, the projections 12j of the first link member 12
Four through holes 16k are provided so as to correspond to 12k and the projections 13n and 13o of the second link member 13,
A plurality of through holes 16g are provided in the membrane contact sheet 16 so as to surround them. The other configuration is the fourth configuration.
This embodiment is the same as the fourth embodiment, and the components are assembled in the same manner as in the fourth embodiment.

In the fifth embodiment having such a configuration, the movable contact 26e contacts the fixed contact 26d and is electrically connected to the fixed contact 26d by pressing the key top 11, similarly to the fourth embodiment. The switch is closed. When the key top 11 is further pressed, the first link member 12 is pressed.
Legs 12a and 12b and leg 13 of the second link member 13
a and 13b enter the inside of the housing 15 and make horizontal contact with the membrane contact sheet 16.

At this time, the leg 12 of the first link member 12
The protrusions 12j and 12k provided on the a and 12b and the protrusions 13n and 13o provided on the legs 13a and 13b of the second link member 13 are provided on the membrane contact sheet 16 as shown in FIG. While deforming the flexible sheet 26a, the flexible sheet 26a enters the inside of the through-hole 16j to cause a buffering action on the key top 21, thereby suppressing the occurrence of a tapping sound.

When the key top 11 is released from being depressed, each component returns to the original state due to the restoring force of the elastic member 14 and the membrane contact sheet 16 as in the fourth embodiment. Also in the fifth embodiment described above, the fourth embodiment
The same effect as that of the embodiment can be expected.

[0069]

As described above, according to the present invention, a membrane sheet having a movable contact and a fixed contact is sandwiched between a housing that supports a keytop so that it can be pressed and a base plate, and the movable contact is formed by pressing the keytop. In a key switch structure for closing a switch by contacting a fixed contact, a housing is formed for each key, and a plurality of fixing pins are formed on the housing so as to surround the movable contact and the fixed contact. A plurality of mounting holes corresponding to the fixing pins are provided, and the housing is fixed to the base plate together with the membrane sheet by press-fitting the fixing pins into these mounting holes.

Therefore, according to this, since the housing in units of one key is fixed at a plurality of locations, the housing can be prevented from floating from the base plate, and the electrical connection position of the key switch can be stabilized. Can be In addition, since the housing in units of one key is formed in units of one key, the effect of increasing the degree of freedom in key arrangement can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention.

FIG. 2 is an exploded perspective view of the first embodiment.

FIG. 3 is a cross-sectional view illustrating a second embodiment.

FIG. 4 is a sectional view showing a third embodiment.

FIG. 5 is a sectional view showing a fourth embodiment.

FIG. 6 is an exploded perspective view of the fourth embodiment.

FIG. 7 is a diagram showing a first link member according to a fourth embodiment.

FIG. 8 is a diagram illustrating a second link member according to a fourth embodiment.

FIG. 9 is a diagram illustrating a housing according to a fourth embodiment.

FIG. 10 is a diagram showing a membrane contact sheet according to a fourth embodiment.

FIG. 11 is a view showing a membrane contact sheet according to a fifth embodiment.

FIG. 12 is a sectional view showing a conventional technique.

FIG. 13 is an exploded perspective view of a conventional technique.

FIG. 14 is a sectional view showing the operation of the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Key top 1a, 1b Rotation support part 1c, 1d Slide support part 1e Slope 2 First link member 2a, 2b Leg 2c First connection rod 2d Second connection rod 2e, 2f Shaft 3 Second link member 3a, 3b Leg Part 3c, 3d First support protrusion 3e, 3f Second support protrusion 3g, 3h Shaft hole 3i Connecting part 4 Elastic member 4a Contact pressing part 5 Housing 5a, 5b Slide guide 5c, 5d Rotation guide 5e Guide wall 5f Fixing pin 5g Deformation Part 6 Membrane contact sheet 6a, 6b Flexible sheet 6c Spacer sheet 6f Through hole 6g Through hole 6d Fixed contact 6e Movable contact 6h Spacer 7 Base plate 7a Spacer protrusion 7b Mounting hole 7c Depression 11 Key top 11a, 1b Rotation support 11c 1d Slide support portion 11e Projection 12 First link member 12a 22b Leg 12c First connection rod 12d Second connection rod 12e, 12f Shaft hole 12k, 12j Projection 13 Second link member 13a, 13b Leg 13c, 13d First support protrusion 13e, 13f Second support protrusion 13g, 13h Shaft 13i, 13j Connecting portion 13n, 13o Projection 14 Elastic member 14a Fitting hole 14b Contact pressing portion 14c Thick portion 15 Housing 15a Slide guide 15b, 15c Rotation guide 15d Guide wall 15e Claw 15h Fixing pin 16 Membrane contact sheet 16a, 16b Possible Flexible sheet 16c Spacer 16d Fixed contact 16e Movable contact 16f, 16h Spacer 16g Through hole 16i, 16k Through hole 17 Base plate 17a Spacer protrusion 17b Mounting hole

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Zenzo Totsuka 1-7-12 Toranomon, Minato-ku, Tokyo Oki Electric Industry Co., Ltd. (72) Inventor Shigeru Yamada 1-7-112 Toranomon, Minato-ku, Tokyo Oki Electric Industry Co., Ltd. F-term (Reference) 5G006 AA01 BA01 BB03 CB01 CB08 CD02 CD07 FB05 FB14 LB01

Claims (8)

[Claims] 1. A membrane sheet having a movable contact and a fixed contact is sandwiched between a housing that supports a keytop so as to be pressed and a base plate, and the switch is closed by pressing the keytop to bring the movable contact into contact with the fixed contact. In the key switch structure, a housing is formed for each key, a plurality of fixing pins are formed in the housing so as to surround the movable contacts and the fixed contacts, and a plurality of mounting holes corresponding to the fixing pins are formed in a base plate. A key switch structure, wherein the housing is fixed to the base plate together with the membrane sheet by press-fitting the fixing pins into these mounting holes. 2. The method according to claim 1, wherein a recess is formed around the mounting hole on the back surface of the base plate, and the tip of the fixing pin press-fitted into the mounting hole is deformed into a flat shape by heating and placed in the recess. A key switch structure characterized by being welded to a concave portion so as to close the mounting hole. 3. The method according to claim 1, wherein the first link member and the second link member are rotatably assembled in an X shape, and one end of the first link member is rotatably supported on the keytop. A second link member rotatably and horizontally movably supported by the key top; and a second end of the first link member rotatably and horizontally movably supported by the housing. The other end of the second link member is rotatably supported by the key top, and the membrane sheet has a structure in which an elastic spacer is sandwiched between two flexible sheets having a movable contact and a fixed contact. Wherein the other ends of the first and second link members are in contact with the membrane contact sheet. 4. The method according to claim 1, 2 or 3.
2. The key switch structure according to claim 1, wherein the housing is formed to have a size that fits inside the key top when the key top is pressed. 5. The substantially cup-shaped elastic member according to claim 1 or 3, wherein a pressing projection for pressing down a movable contact of the membrane contact sheet is provided at the center of the inner surface between the keytop and the membrane contact sheet. A key switch structure, wherein a ring-shaped guide wall for supporting the entire lower periphery of the elastic member is formed inside the housing. 6. The housing according to claim 3, wherein a projection for guiding the outer surface of the second link member is provided on the housing when the first and second link members are rotated by pressing the key top. Key switch structure. 7. The method according to claim 3, wherein a projection is provided on the lower surface of each of the first and second link members, and a ring-shaped spacer is provided between the flexible sheets of the membrane sheet so as to correspond to the projection. The key switch structure, wherein when the first and second link members are rotated by the depression of the key top, the respective protrusions deform the flexible sheet to enter the spacer. 8. The spacer according to claim 3, wherein a projection is provided on the lower surface of each of the first and second link members, and a through-hole is formed in a spacer provided between the flexible sheets of the membrane sheet so as to correspond to the projection. When the first and second link members are rotated by the depression of the key top, the respective protrusions deform the flexible sheet and enter the through holes. Key switch structure.