JP2574040Y2 - Keyboard switch - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a keyboard switch, and more particularly to a keyboard switch suitable for use in a keyboard of a computer or other electronic devices.

[0002]

2. Description of the Related Art An example of this type of keyboard switch is shown in FIG. A bar-shaped key stem 3 is formed at the center of the lower surface of the top portion 2 of the key top 1 having a square inverted dish shape when viewed from above. In the vicinity of the end of the top part 2, a locking piece 4 is further provided.
Is formed, and a locking claw 4a is formed at the lower end thereof. A pair of locking pieces 4 are provided symmetrically,
FIG. 6 shows only one of them. The key top 1 is formed from a synthetic resin material.

A housing 5 of the keyboard has a cylindrical guide 6 and a locking hole 7 formed therein. The key stem 3 of the key top 1 is fitted into the guide portion 6 so as to be slidably guided, and the locking piece 4 of the key top 1 is inserted into the locking hole 7 so that the locking claw 4a is formed. The locking hole 7 is locked on the lower surface of the periphery. The lower end of the flared elastic member 8 made of rubber or other elastic material is attached to the outer periphery of the guide portion 6, which interposes between the upper surface of the housing 5 and the lower surface of the keytop 1 to bias the keytop 1 upward. Lifting. In this case, the locking claw 4a of the locking piece 4 is locked to the lower surface of the peripheral portion of the locking hole 7 to limit lifting.

A plate 9 is arranged below and parallel to the housing 5, and a membrane sheet 10 is mounted on the upper surface of the plate 9. Membrane sheet 1
Numeral 0 is composed of two flexible membranes and these separators. One of the membranes has a contact 11a on the lower surface and the other has a contact 11b on the upper surface, and the contacts 11a and 11b face each other. Constitutes the contact portion of the keyboard switch.

Here, the key stem 3 is guided by the guide portion 6 by pressing the key top 1 and slides. The lower end of the key stem 3 presses the upper surface of one of the membranes of the membrane sheet 10 to change the contact 11a to the contact 11b. Contact. The above-described keyboard switch includes a key stem 3 and a guide portion 6.
A sliding portion is constituted by the above. In this case, since the diameter of the key stem 3 or the inner diameter of the guide portion 6 is relatively small, when the corner or the end of the key top 1 is pressed, the distance between the point where the pressing force is applied and the sliding portion is increased. The distance becomes longer.
Therefore, the key stem 3 and the guide portion 6 come into strong contact with each other from the place where the rotational moment of the key top 1 becomes large, and the key top 1 does not move smoothly.

A keyboard switch that solves this difficulty has also been proposed, and will be described below with reference to FIGS. The key top 1 has a plurality of guide portions 16 a to 16 d formed on the lower surface of the top portion 2. The positions where these guide portions are formed are preferably as far as possible from the center O of the top portion 2. In this example, the guide portions are formed at four corners on a diagonal line of the square top portion 2. Guide part 1
The inner surfaces of 6a to 16d have a radius R from the center O of the key top 1.
α on the cylindrical surface, and therefore each guide 16a
16d are equidistant from the center O of the top part 2.

A virtual orthogonal line passing through the center O is defined as X and Y, lines connecting the right end and left end of the guide portion 16d and the center O are defined as x and y, respectively, and an angle between the line X and x is α.
_a , the angle between the line Y and y is α _b , and the angle between the line x and y is α _c , α _a = α _b.
1 ° is chosen and the angle α _c is chosen to be 28 °. Guide part 1
The same applies to 6a to 16c. On the lower surface of the key top 1, a pair of locking pieces 4 are provided at symmetrical positions, and the lower ends thereof are locking claws 4a. A cylindrical key stem 15 is further formed in the center of the lower surface of the key top 1.

The housing 5 has a cylindrical portion 17 and four guide portions 18a to 18d. Cylindrical part 17
As shown in FIG. 4, the key top 1 is composed of a lower large diameter portion 17a and an upper small diameter portion 17b, and the key stem 15 of the key top 1 is loosely inserted into the small diameter portion 17b. Guide part 1
The outer surfaces of 8a to 18d have a radius R from the center P of the cylindrical portion 17.
on a cylindrical surface with β. This radius Rβ is formed to be equal to or slightly smaller than the radius Rα described above,
The inner surfaces of the guide portions 16a to 16d of the key top 1 are slidably guided.

In FIG. 3, a virtual line W and a virtual line Z pass through the center P and correspond to the virtual lines X and Y shown in FIG. Lines connecting the right and left ends of the guide portion 18d and the center P are denoted by w and z, respectively, the angle between the lines W and w is βa, the angle between the lines Z and z is β _b , and the angle between the lines w and z is When β _c is set, β _a = β _b = β _c is selected, and each is selected at 30 °. The same applies to the guide portions 18a to 18c.

At a position forming a left and right pair of the large diameter portion 17a of the cylindrical portion 17, a part thereof is extended upward to
Are formed on the locking claw 4 of the locking piece 4 of the key top 1.
a, the stationary position of the key top 1 is determined, and the lower end of the key stem 15 and the membrane sheet 1
The key top 1 is lifted upward with an elastic member (return rubber) 8 interposed between the key top 1 and the upper surface of the key top 1. Elastic member 8
Is composed of a tubular portion 8a, a flared portion 8b, and a middle wall 8c that is continuous with the lower end of the tubular portion 8a, and a convex portion 8d is formed at the center of the middle wall 8c. The cylindrical part 8a is the key top 1
Is fitted in the key stem 15.

The housing 5 has guide portions 18a to 18
d, outer holes 20a to 20d are formed in the outer portion, and a pair of projections 19a and 19b are formed on both left and right edges of the escape holes. As shown in FIG.
Guide portions 16a to 16d. Escape holes 22a and 22b are formed in the cylindrical portion 17 below the locking portion 21.

When the key top 1 is pressed against the elasticity of the elastic member 8, the guides 16a to 16d are slidably guided by the guides 18a to 18d of the housing 5, and the key top 1 is lowered. Projection 8d of elastic member 8
Presses the upper surface of the membrane sheet 10 to bring the contact 11a into contact with the contact 11b. At this time, the lower ends of the guide portions 16a to 16b of the key top 1 escape into the escape holes 20a to 20d of the housing 5, respectively.
Of the locking piece 4 escapes into the escape holes 22a and 22b, so that the housing 5 does not interfere. When the fingertip is released from the key top 1, the key top 1 is returned to the original position by the elastic member 8.

This keyboard switch is a key top 1
Guides 16a to 16d and guide 1 of housing 5
8a to 18d constitute the key top 1
Are divided into four parts at a position sufficiently separated from the center of the key top 1, that is, a position near the four corners of the key top 1. Therefore, even if any one of the four corners of the key top 1 is pressed, the pressing position becomes near any of the sliding portions, and the rotational moment acting on the key top 1 is smaller than that of the keyboard switch shown in FIG. Since the size is small, the key top 1 is smoothly moved downward.

[0014]

In the keyboard switch as described above and shown in FIGS. 2 to 5, even if any one of the four corners of the key top 1 is pressed, the pressing position is any one of the sliding portions. In the vicinity, the rotational moment acting on the key top 1 is smaller than that of the keyboard switch shown in FIG. 6, so that the key top 1 is smoothly moved downward.

Since the locking claw 4a of the locking piece 4 of the key top 1 is engaged with the lower surface of the locking portion 21, the key top is almost displaced with respect to the vertical center axis W of the key top 1 in FIG. Do not tilt. However, with respect to the center axis Z in the horizontal direction, a predetermined clearance is required between the inner surfaces of the guide portions 16a to 16d of the key top 1 constituting the sliding portion and the corresponding outer surfaces of the guide portions 18a to 18d of the housing 5. Since the guide portion 16 is provided, the guide portion 16 of the key top 1 has the guide portions 18a to 18
d Displaced and inclined from the outer surface. At the moment when the key top 1 is pressed to start moving, the guides 16a to 16d of the key top 1 are inclined and hit the corresponding guides 18a to 18d of the housing 5 due to the inclination in the horizontal direction. The friction between them increases, and the pressing operation feeling deteriorates accordingly.

The present invention provides a keyboard switch that solves the above-mentioned problems.

[0017]

A plurality of key top guide portions 16a to 16a are provided at positions sufficiently distant from the center of the lower surface of the top portion 2.
16d is provided with a key top 1 which is suspended form, the plurality of key tops guide portions 16a~16d each provided with a housing 5 in which the housing guide portion 18a~18d is formed for sliding guide, the key top 1 and the housing 5 is provided with an elastic member 8 interposed between the membrane 5 and the membrane sheet 10 disposed below the key top 5 to shift the key top 1 upward .
A locking portion 21 is provided facing each other, and a top portion is provided.
2 a pair formed opposite the lower surface and locked to the locking portion 21
In the keyboard switch having a locking piece 4, bets
An inclination prevention rib 50 is a key top guide on the lower surface of the tap portion 2.
When formed in parallel with the extending direction of the portions 16a to 16d,
In addition, the housing 5 has a pair of guides for guiding the inclination preventing ribs 50.
Guide plates 51 _1, 51 ₂ constituted the keyboard switch formed.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is summarized in FIGS.
Is provided with a tilt prevention rib and a guide portion 51 for guiding the same.
Hereinafter, this will be described with reference to FIG. A tilt prevention rib 50 is provided on the lower surface of the top portion 2 as a key top guide portion.
It is formed parallel to the stretching direction of 16a to 16d . The installation position is preferably as far as possible from the center O of the top portion 2, and is eventually installed at the end portion of the virtual line Y of the key top 1. Then, the housing 5 is provided with an inclination prevention
Guide plates 51 _1, 51 ₂ is erected a pair of guiding the blanking 50
Thus, a guide groove 51 for guiding the inclination preventing rib 50 is formed. The inclination preventing rib 50 is formed so that the tip is smaller than the root and has a cut surface, so that it does not hinder the key top pressing operation. The ribs 50 for preventing inclination and the guide grooves 51 for guiding the ribs do not displace or incline the guide portions 16a to 16d of the key top 1 from the corresponding outer surfaces of the guide portions 18a to 18d of the housing 5 in the fitted state. It is configured in a shape fitting state in which the shape is parallel to each other. By the inclination prevention rib 50 and the guide groove 51 for guiding the same,
Regarding the horizontal center axis Z, the guide portion 16 of the key top 1 is prevented from tilting between the guide portions 18a to 18d and the key top of the keyboard switch is not tilted.

[0019]

Be as above, according to the invention], the key top 1 of the keyboard switch of this invention, in a state where no pressing, with respect to the center axis W in the vertical direction in FIG. 3, Howe
A pair of opposing pairs formed to extend above the jing 5.
Formed opposite to the locking portion 21 and the lower surface of the top portion 2
It is almost inclined by a pair of locking pieces 4 locked to the locking portion 21.
It is kept in a state. With respect to the horizontal center axis Z
Is the key top and the key top guide is on the bottom of the top part 2.
Slope prevention formed parallel to the extending direction of the portions 16a to 16d
Anti-tilt ribs formed on the stop rib 50 and the housing 5
殆by a guide plate 51 _1, 51 ₂ a pair for guiding the blanking 50
It is kept in a state where it does not tilt. By doing so, at the moment when the key top 1 is pressed to start moving, the guides 16a to 16d of the key top 1 start moving in a state parallel to the corresponding guides 18a to 18d of the housing 5. Therefore, at this moment, no friction is particularly generated between the two members, and thereafter, the pressing operation feeling is very good from the position guided by the two guide portions.

[Brief description of the drawings]

FIG. 1 illustrates an embodiment.

FIG. 2 is a bottom view of a key top of the keyboard switch.

FIG. 3 is a plan view of a part of a keyboard switch housing.

FIG. 4 is a sectional view showing an engagement state between the key top and the housing.

FIG. 5 is a sectional view taken along line CC in FIG. 4;

FIG. 6 is a sectional view showing a conventional example of a keyboard switch.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Key top 2 Top part 5 Housing 8 Elastic member 10 Membrane sheet 16 Guide part 18 Guide part 50 Inclination prevention rib 51 Guide groove

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H01H 13/00-13/76 G06F 3/02

Claims (1)

(57) [Scope of request for utility model registration] 1. A plurality of key top guide portion sufficiently distant from the center of the top lower surface is provided with a key top which is suspended form, the plurality of key tops guide portion is a housing guide portion for each sliding guide And a resilient member interposed between the keytop and a membrane sheet disposed below the housing to shift the keytop upward, the housing further comprising
A pair of locking portions extending toward each other
And a locking portion formed opposite the lower surface of the top portion.
A keyboard switch having a pair of locking pieces for locking the key top guide portion with a tilt preventing rib on the lower surface of the top portion.
It is formed parallel to the stretching direction and tilted to the housing.
A keyboard switch, wherein a pair of guide plates are provided upright to guide the skew prevention rib .