JPH0544975Y2 - - 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 such as a personal computer or a word processor, and particularly relates to an improvement in the structure of a support on a torsion bar.

[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 portion 4b of the torsion bar 4 rotates as an axis within the mounting portion 3b of the torsion bar holder 3, and the tip portion 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.

[Problem that the invention attempts to solve]

However, in the above-mentioned conventional key top holding structure, the torsion bar 4 is attached between the torsion bar receiver 3 and the torsion bar support 6 attached to the underside of the key top 5, and when the key top 5 is pressed, the attachment portion 3b of the torsion bar receiver 3
The torsion bar 4 rotates around the central part 4b of the torsion bar 4 located inside the switch, and the torsion bar support 6 moves downward, but because the key top 5 is designed to continue to move downward even after the switch is turned ON, the underside of the lever support 3 comes into contact with the printed circuit board 1, causing an impact noise. Therefore, as shown in Japanese Utility Model Application Laid-Open Publication No. 62-18930, a contact prevention member made of synthetic resin is provided on the printed circuit board facing the torsion bar support in an attempt to solve the above problem, but the installation work required to install the contact prevention member on the printed circuit board is time-consuming, which in turn causes a problem of poor assembly workability.

Therefore, the present invention has good assembly workability, and
An object of the present invention is to obtain a member capable of preventing impact noise from a torsion bar support.

[Means for solving problems]

In order to solve the above technical problems, this invention
A push button switch having a stem and a plurality of torsion bar receivers are arranged on the board, and a mounting part that can be attached to the stem is provided in the center of the lower surface of the key top.
In a keyboard key top holding structure comprising torsion bar supports at both ends of the lower surface, and a torsion bar interposed between the torsion bar supports, the torsion bar support has an abutment portion having an uneven surface. The torsion bar support is integrally formed, and the lower surface of the torsion bar support is configured to be able to come into contact with the abutting portion when the key top is pressed.

[Effect]

In the present invention, a contact part with an uneven surface is integrally formed on the torsion bar support, and the lower surface of the torsion bar support is brought into contact with the convex part of the contact part when the key top is pressed. The impact noise generated when the contact part contacts the contact part is reduced.

Furthermore, since the contact portion is integrally formed with the torsion bar receiver, ease of assembly is improved.

〔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 that is attached to the groove 15c of the fitting part 15b of the key top 15. 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, the torsion bar support contact portion 13 has an uneven surface on the torsion bar support 13.
This is a configuration in which a is integrally provided.

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. The upper surface of the holding portion 13c is also formed with an uneven surface similar to the torsion bar support abutment portion 13a, and one end portion 15c of the key top 15 is placed thereon 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 abutment part 13a, and the lower surface of one end 15c of the key top 15 abuts on the holding part 13c 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. Further, since one end 15c of the key top 15 can also come into contact with the holding part 13c, when the key top 15 is pressed, the key top 15 comes into contact with the upper surface of the torsion bar support contact part 13a and the holding part 13c, and the inclination of the key top 15 is prevented. Prevented.

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, and the fitting protrusion 1
This is to provide elasticity when attaching the 3P 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.

Incidentally, the torsion bar receiver 13 of the above embodiment is as follows:
The torsion bar support contact portion 13a is formed into a substantially W shape, and the torsion bar support is in line contact with the upper end of the W shape, but this is just one example, and other methods may be used as long as they can reduce impact noise. It may be a configuration.

(For example, point contact) [Effects of the invention] As described above, the present invention integrally forms a contact portion with an uneven surface on the torsion bar receiver,
Since the lower surface of the torsion bar support is brought into contact with the convex portion of the abutting portion when the key top is pressed, it is possible to prevent an impact sound generated when the key top is pressed.

Further, since the abutting portion is integrally formed with the sheathing bar receiver, assembly work can be easily performed.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective 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... Contact part (torsion bar support contact part),
14... Torsion bar, 15... Key top,
15a... Attachment part (fitting protrusion), 16... Torsion bar support.

Claims (1)

[Scope of utility model registration request] A push button switch having a stem and a plurality of torsion bar holders are arranged on the board, a mounting part that can be attached to the stem is provided at the center of the lower surface of the key top, torsion bar supports are provided at both ends of the lower surface, and the above-mentioned In a key top holding structure for a keyboard in which a torsion bar is interposed between a torsion bar support and a torsion bar support, a contact portion having an uneven surface is integrally formed on the torsion bar support, and the torsion bar support is held in place when the key top is pressed. A key top holding structure for a keyboard, characterized in that the lower surface is configured to be able to abut against the abutting portion.