JPH0535540Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a key top holding structure for a keyboard used as various input devices for personal computers, word processors, etc., and particularly relates to an improvement in the structure of a torsion bar holder.

[Conventional technology]

As a conventional key top holding structure of this type, Japanese Utility Model Application Publication No. 59-69446 is known. An example of such a keytop holding structure will be explained based on FIG. 5.

In the figure, 1 is a printed circuit board, and this printed circuit board 1 has a terminal insertion hole 1a into which a terminal 2a of a push button switch 2 can be inserted, and a reinforcing metal fitting 2b for fixing the push button switch 2 to the printed circuit board 1 can be inserted. A reinforcing metal fitting insertion hole 1b and a mounting hole 1c for mounting the torsion bar holder 3 are formed. The push button switch 2 has a roughly rectangular cutout groove 2 in the center.
A stem 2d having a shape c formed thereon, and a contact portion (not shown) that is housed in the case 2e and comes into contact with the stem 2d when the stem 2d moves downward are provided, and the end of the contact portion protrudes downward from the case 2e. A terminal 2a is provided. Note that the stem 2d is positioned in an upwardly protruding state by the spring pressure of a coil spring (not shown). The pair of torsion bar receivers 3 have a notch 3a formed in the upper part and a mounting part 3b in the center to which the torsion bar 4 can be mounted. It is arranged by tightly fitting into the mounting hole 1c of.

On the other hand, a fitting protrusion 5a that can be fitted into the notch groove 2c of the stem 2d is provided at approximately the center of the lower surface of the horizontally elongated key top 5, and a fitting protrusion 5a that can be fitted into the notch groove 2c of the stem 2d is provided at both ends of the lower surface, and a torsion bar is provided inside. A fitting portion 5b to which the support 6 can be attached is formed. The torsion bar support 6 is formed with a fitting protrusion 6a on the upper side, which can be attached to the groove 5c of the fitting part 5b. The torsion bar 4 is formed into a substantially C-shape, and the tip portion 4a is engaged with a cutout portion 6b of the torsion bar 6, and the center portion 4b is rotatably attached to the attachment portion 3b of the torsion bar holder 3. A terminal 2a of the push button switch 2 is soldered to the printed circuit board 1.

With the above configuration, when the key top 5 is pressed, the stem 2d of the push button switch 2 moves downward, the center part 4b of the torsion bar 4 rotates as an axis within the mounting part 3b of the torsion bar holder 3, and the tip part 4a
slides in the notch 6b of the torsion bar support 6 in the direction of the arrow, and the internal contacts come into contact, turning the switch ON. Then, when the pressure on the key top 5 is released, the spring pressure of the coil spring returns to the original state, and the switch is turned OFF.

[Problems to be Solved by the Invention] However, in the conventional key top holding structure described above, there is a problem in that the key top 5 tilts or wobbles when the key top 5 is pressed to the lowest value. In other words, the torsion bar support 6 is at the lowest position of the key top 5.
The tip 4a of the torsion bar 4 moved within the notch 6b of the torsion bar 6, causing the key top 5 to tilt or wobble at the lowest position of the pressing operation. Therefore,
Since the key top 5 moves instantaneously during the press, the operator does not feel that the operability is degraded even if the key top 5 is tilted a little. I felt it was bad.

Therefore, an object of the present invention is to provide a key top holding structure that prevents the key top from tilting at the lowest position when the key top is pressed.

[Means for solving the problem] A push button switch mounted on a board, a key top fixed to a stem of the push button switch, and a series of parallel sides having first sides and second sides facing each other. A key top holding structure having a torsion bar is characterized in that a portion is provided on at least one of the substrate or the back surface of the key top to maintain the key top horizontally by coming into contact with the key top or the substrate at the lowest position of the key top press. shall be.

[Function] With the above configuration, the key top is maintained horizontally at the lowest position of the key top by the contact portion provided on at least one of the key top and the base plate. Therefore, it is possible to prevent the conventional inconvenience of the key top tilting or wobbling at the lowest position of the key top.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

Fig. 1 is an exploded perspective view of the key top holding structure, Fig. 2 A is a side view of the main parts showing the assembled state of each member in Fig. 1, and Fig. 2 B shows the state in which the key top in Fig. 2 A is pressed. 3A and 3B are a side view and a bottom view showing the first embodiment of the torsion bar receiver,
4A and 4B are a side view and a bottom view showing a second embodiment of the torsion bar receiver.

The key top holding structure of the present invention also has a terminal insertion hole 11a into which the terminal 12a of the push button switch 12 can be inserted.
, a printed circuit board 11 having a reinforcing metal fitting mounting hole 11b to which a reinforcing metal fitting 12b for fixing the push button switch can be attached, a push button switch 12 having a stem 12d in which a cutout groove 12c is formed, and a stem 12d in the center of the lower surface. A key top 15 is provided with a fitting protrusion 15a that can fit into a notched groove 12c, and a fitting part 15b is provided at both ends of the lower surface, and a torsion bar support to which the groove 15c of the fitting part 15b of the key top 15 is attached. 16, the tip portion 14a is engaged with the notch portion 16a of the torsion bar support 16, and the center portion 14b is engaged with the torsion bar support 13.
The torsion bar 14 fitted into the torsion bar 14 is similar to the conventional one, but the present invention is characterized by the following configuration.

That is, a torsion bar support abutment part 13a where the torsion bar support 16 can come into contact with the torsion bar support 13, and one end part 1 of the key top 15.
5c is provided with a key top abutting portion 15z that can be abutted.

The structure of the torsion bar holder 13 will be explained in detail. First, holding parts 13c and 13d that protrude upward from the base 13b and rotatably hold the center part 14b of the torsion bar 14 are provided at one end, and a protrusion 1 is provided inside the holding parts 13c and 13d.
3e and 13f are provided to prevent the center portion 14b of the torsion bar 14 from coming off upward. At the other end, a torsion bar support abutment part 13a is provided which is connected to the base part 13b and has an uneven upper surface, and has a substantially W-shaped cross section. Also, on the lower surface of both ends, a fitting protrusion 1 having a protrusion 13h at the tip.
3k is provided. A curved central portion 13m is provided between the base portion 13b and the torsion bar support contact portion 13a.
A recessed portion 13n is formed on the lower surface of the torsion bar support contact portion 13a. A key top contact part 13z having an uneven surface like the torsion bar support contact part 13a is also formed on the upper surface of the holding part 13c, on which one end part 15c of the key top 15 is placed when the key top 15 is pressed. . Further, an inclined surface is formed on the lower surface 16b of the tip of the torsion bar support 16, and this inclined surface does not come into contact with the torsion bar support contact portion 13a.

When assembling the key top holding structure having the above configuration, the terminal 1 of the push button switch 12 is inserted into the terminal insertion hole 11a of the printed circuit board 11 and the reinforcing metal fitting insertion hole 11b.
2a and reinforcing metal fittings 12b, and attach the torsion bar holder 1 to the torsion bar holder mounting hole 11c.
The fitting protrusion 13k of No. 3 is fitted. The center portion 14a of the torsion bar 14 is fitted in a snap-in manner between the holding portions 13c and 13d of the torsion bar holder 13, thereby being rotatably attached. On the other hand, the tip 14a of the torsion bar 14 is inserted into the notch 16a of the torsion bar support 16 which is pre-attached to the fitting parts 15b at both ends of the lower surface of the key top 15, and the fitting protrusion 15a at the center of the lower surface is inserted into the stem 12d. It is attached by fitting into the notch groove 12c of the. (State A in Fig. 2) When the key top 15 is pressed, the stem 12d moves downward and the torsion bar holding parts 13c, 13
Central part 1 of torsion bar 14 attached to d
The tip 14a has a notch 16a with the axis 4b as the axis.
As the stem 12d slides downward, the internal contacts come into contact and the switch is turned on. and,
When the key top 15 is further pressed, the lower surface of the torsion bar support 16 abuts on the torsion bar support abutting part 13a, and the lower surface of one end 15c of the key top 15 abuts on the key top abutting part 13z of the torsion bar receiver 13. When the pressure on the key top 15 is released, the return force of the coil spring within the push button switch 12 returns it to its original state.

The torsion bar support 13 of the above embodiment is integrally provided with a torsion bar support abutment part 13a which can be brought into contact with the lower surface of the torsion bar support 16 and has an uneven surface.
It is possible to suppress the impact sound when pressing 5. Furthermore, since the one end 15c of the key top 15 can also come into contact with the key top abutting part 13z of the holding part 13c, when the key top 15 is pressed, the key top 15 touches the upper surface of the torsion bar support abutting part 13a and the key top abutting part 13z. This abuts and prevents the key top 15 from tilting.

FIGS. 4A and 4B show a second embodiment of the torsion bar holder, and the difference from the first embodiment is that the mounting structure to the printed circuit board 11 has been improved, and the lower surface of the base 13b and the central part 13m are different from the first embodiment. A pair of fitting protrusions 13p are provided adjacent to the lower surface, and a cylindrical protrusion 13r is provided on the lower surface of the torsion bar support contact portion 13a. A groove 13s is formed between the outside of both sides of the fitting protrusion 13p and between the fitting protrusion 13p.
This is to provide elasticity when attaching P to the printed circuit board 11. Furthermore, a rib 13u is provided on the protrusion 13r to increase the strength of attachment to the printed circuit board 11.

In the above embodiment, when the key top 15 is pressed, the key top abutting portion 13z of the holding portion 13c is such that the lower surface of the one end 15c of the key top 15 projects upward.
The torsion bar support 16 is in contact with the base 1.
3b and comes into contact with the torsion bar support abutment part 13a that is approximately the same height as the base 13b, but this is just one example, and other configurations may be used as long as the key top 15 does not tilt when the key top is pressed. It may be in the shape of

[Effect of idea]

As described above, the present invention can provide a keyboard with excellent operability without the key tops tilting or wobbling when the keyboard is pressed to the lowest position.

[Brief explanation of the drawing]

Fig. 1 is an exploded inclined view of the key top holding structure of the present invention, Fig. 2 A is a side view of the main parts showing the assembled state of each member of Fig. 1, and Fig. 2 B is a pressing of the key top of Fig. 2 A. FIGS. 3A and 3B are side and bottom views showing the first embodiment of the torsion bar holder of the present invention, and FIGS. 4A and B are the second embodiment of the torsion bar holder of the present invention. FIG. 5 is an exploded perspective view showing a conventional key top holding structure. 11... Board, 12... Push button switch, 12d
... Stem, 13 ... Torsion bar receiver, 13
a... Torsion bar support contact part, 13z... Key top contact part, 14... Torsion bar, 15
...Key top, 15c... End, 16... Torsion bar support.

Claims (1)

[Scope of utility model registration request] A keytop holding structure comprising a pushbutton switch mounted on a substrate, a keytop fixed to a stem of the pushbutton switch, and a series of torsion bars having parallel first sides and second sides facing each other. 1. A key top holding structure for a keyboard, characterized in that a contact portion is provided on at least one of the substrate or the back surface of the key top by contacting the key top or the substrate at the lowest position when the key top is pressed to maintain the key top horizontally.