JPS631397Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a key switch device in which a switch mechanism is switched and set by rotating an inserted key.

1 to 3 show a conventional key switch device. A sleeve 12 and a box 13 constituting the case 11 are integrally fixed by a frame 14. An opening 12 ₁ is provided in the distal end surface of the sleeve 12, and a key insertion hole _{15 1 provided} in the guide plate 15 is exposed in this opening 12 1. The peripheral edge of the guide plate 15 is rotatably pressed against the inner surface of the sleeve ₁₂ by a cylindrical coil spring 16 having a diameter larger than the length a of the key insertion hole 151. Said coil spring 1
Reference numeral 6 is provided at the periphery of the upper end of a cylindrical rotating member 17 that is rotatably provided inside the box 13 and the sleeve 12. The upper end of the rotating member 17 is provided with a recess 17 ₁ into which a key (not shown) inserted into the key insertion hole 15 ₁ is inserted.
Further, a through hole ₁₇₂ is formed in the rotary member 17 located inside the box 13, and the diameter thereof matches the diameter of the rotary member ₁₇ . Steel balls 19 and 20 are provided which are biased by a coil spring 18 in a direction to project from the rotating member 17. These steel balls 1
9 and 20 are adapted to be pressed into contact with a plurality of recesses 13 ₁ and protrusions 13 ₂ formed on the inner surface of the box 13, respectively, and the rotating member 17 is connected to these steel balls 19 and 20 and recesses 13 1 and 13 ₂ , respectively. It is articulated by the protrusion ₁₃₂ . Furthermore, recesses 17 ₃ and 17 ₄ are formed in the lower surface of the rotating member 17 and spaced apart by a predetermined distance in a direction perpendicular to the through hole 17 ₂ . These recesses 17 ₃ and 17 ₄ have coil springs 21 and 21, respectively.
Movable contact pieces 23 and 24 are provided which are biased in a direction protruding from the rotating member 17 by a movable contact piece 22.
These movable contact pieces 23 and 24 come into contact with a switch pattern (not shown) formed on the surface of a printed circuit board 25 disposed on the bottom surface of the box 13. These switch patterns are connected to a plurality of terminals 26 arranged at the bottom of the box 13. Therefore, as the rotating member 17 rotates, the movable contact piece 2
3 and 24 are brought into contact with a predetermined switch pattern,
The switch state is changed and set. Note that 27 is a holding member that positions and holds the rotating member 17.

By the way, in the above configuration, the key inserted through the key insertion hole 15 ₁ of the guide plate 15 is inserted in and out of the key insertion hole 15 ₁ (arrow A shown in FIG. 2,
B direction) is completely free. For this reason, when this key switch is mounted horizontally, for example, there is a problem in that the key easily comes off from the key insertion hole ₁₅₁ due to vibration or the like.

This invention was made based on the above circumstances, and its purpose is to make a part of the coil spring that holds the guide plate rotatably pressed against the inner surface of the sleeve narrower than the length of the key insertion hole, By holding the inserted key in pressure contact with this coil spring, it is possible to prevent the key from falling off with a simple configuration without increasing the number of parts.
The present invention aims to provide an economically advantageous key switch device.

An embodiment of this invention will be described below with reference to the drawings. In addition, in FIGS. 4 and 5, the same parts as in FIGS. 1 to 3 are given the same symbols,
Only the different parts will be explained.

4 and 5, what is different from the conventional one is the elastic member that holds the guide plate 15 in pressure contact. In this embodiment, for example, a conical coil spring 51 is used in which the diameter of the portion that contacts the guide plate 15 is slightly narrower than the length of the key insertion hole ₁₅₁ .

With this configuration, when the key is inserted into the key insertion hole ₁₅₁ , the key is held in pressure contact by the small diameter portion of the coil spring 51, so that it is possible to prevent the key from falling off due to vibration or the like.

Further, according to this configuration, the number of parts does not increase compared to the conventional one. Therefore, the number of assembly steps is the same as in the past, and it is economically advantageous.

Note that this invention is not limited to the above embodiments. That is, the diameter of a part of the cylindrical elastic member that holds the guide plate 15 is narrower than the length a of the key insertion hole 15 ₁ , such as the coil spring 61 shown in FIG. The diameter of the center portion may be smaller than that of both ends.

Furthermore, this elastic member is not limited to coil springs, but coil springs 51 and 6 shown in FIGS. 5 and 6.
A similar effect can be obtained by using a rubber material formed to have the same cross-sectional shape as No. 1.

It goes without saying that various other modifications can be made without departing from the gist of the invention.

As described above in detail, according to this invention, it is possible to provide an economically advantageous key switch device which can prevent the key from falling off with a simple structure without increasing the number of parts.

[Brief explanation of the drawing]

Figures 1 to 3 show a conventional key switch device, in which Figure 1 is a top view, Figure 2 is a side sectional view, and Figure 3 is a partially cutaway top view showing the configuration of the rotating member. , 4 and 5 show one embodiment of the key switch device according to this invention, FIG. 4 is a top view, FIG. 5 is a side sectional view, and FIG. 6 is another embodiment of the elastic member. It is a side sectional view showing an example. 11...Case, 12...Sleeve, 13...
Box, 15... Guide plate, 15 ₁ ... Key insertion hole, 23, 24... Movable contact piece, 51, 61...
coil spring.

Claims (1)

[Scope of utility model registration request] a case; a guide plate having a key insertion hole exposed on the surface of the case and rotatably held in pressure contact with the inner surface of the case by an elastic member; and a guide plate provided inside the case and provided in the key insertion hole. A key switch device comprising a rotating member that is rotated by an inserted key to switch and set a switch mechanism, wherein the elastic member is a cylindrical elastic member whose diameter is partially narrower than the length of the key insertion hole. A key switch device characterized in that the key inserted into the key insertion hole is held in place by the elastic member.