JPH0139260B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a structure of a key top suitable for use in a push-button dial of a telephone.

[Prior art]

Traditionally, telephones have employed rotary dials and push-button dials. Among these, the push-button dial operates a switch by pressing a key top (push button) to connect a telephone line, and does not require a mechanical mechanism compared to a rotary dial, which reduces the number of parts. Improves assembly workability and makes it thinner and lighter.
In addition to the dial buttons from 0 to 9, memory,
Since it is equipped with function buttons such as redial, it has the advantage of being highly functional and convenient. There are two types of key tops: one in which each key top is formed separately, and the other in which multiple key tops are formed integrally and adjacent key tops are connected to each other.In the former case, the number of parts increases, Manufacturing and assembly work is troublesome and there is a risk of incorrect assembly, so sufficient care must be taken. On the other hand, although the latter has the advantage of eliminating the above-mentioned inconvenience, since adjacent key tops are connected by a connecting plate, when one key top is pressed, other adjacent key tops also move and become independent. It had the disadvantage of lacking sex.

In addition, each type uses a spring to return each key top to its original position, which requires work to assemble the springs, and furthermore, it is difficult to provide a uniform operating feel due to variations in the springs.

[Summary of the invention]

The present invention has been made in view of the above-mentioned points, and has the structure of a key top that is assembled inside a housing and whose operation surface is exposed to the outside of the housing and is operated by pressing.
A frame, a key top spaced apart from the frame, and a pair of left and right support arms connecting the key top and the frame are integrally formed,
The pair of support arms each extend from the frame and have elasticity, and their free ends are connected to the circumferential surface of the key top on the side opposite to the frame, and are slightly lower than the upper surface of the frame. The frame is floating, and has an extremely simple structure in which the upper surface of the frame abuts the inner surface of the equipment casing and the support arm is pressed against the inner surface of the equipment casing, eliminating the need for a return spring and allowing the use of multiple key tops. The present invention provides a key top structure that is highly independent even when integrally molded, and allows each key top to have uniform stability, operability, and height.

〔Example〕

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

FIG. 1 is a perspective view showing an embodiment of the key top according to the present invention applied to a push-button dial of a home telephone, FIG. 2 is a plan view of the key top, and FIG. 3 is a side view of the same key top. In FIG. 1, a home telephone 1 includes a telephone housing 2, a handset 3,
It has a push-button dial 4 and the like and is installed on a tabletop or wall surface, and this in-home telephone 1 is connected to indoor wiring via a telephone cord 5.

The telephone housing 2 is composed of a shallow box-shaped lower housing 2A with an open upper surface, and an upper housing 2B that is integrally connected to the lower housing 2A. In the first half of the top surface, there are 3 horizontal buttons and 4 vertical buttons in total, corresponding to the push button dial 4.
Twelve round holes 11 are formed.

The push button dial 4 is made of a plastic material such as ABS and has a cylindrical shape, and numbers 0 to 9 are displayed on the top surface by two-color molding, thereby forming ten key tops 10a to 10j that constitute a dial button. It is also formed in a cylindrical shape, and the * and # symbols are displayed on the top surface by two-color molding, forming the memory and redial function buttons.
The key tops 10a to 10l are respectively inserted into the round holes 11 of the upper housing 2B from the inside so as to be slidable in the axial direction, and their upper ends protrude outside. There is. Further, the push button dial 4 has the key tops 10a to 10 as shown in FIGS. 2 and 3.
These key tops 10 are formed at the same time as the molding of l.
A frame 13 surrounding a to 10l, and this frame 13
The frame 15 is formed by three partition plates 14A, 14B, and 14C that partition the inside of the frame into four spaces long in the left-right direction. The frame body 13 has one on its left side plate and two on its right side plate 13b.
It has a total of three elastic engagement pieces 16 (see FIG. 4) formed in three elastic engagement pieces 16 (see FIG. 4), and a pair of left and right screw attachment parts 17 formed on the rear plate 13c.
is inserted into an engagement hole (not shown) of a printed circuit board 18 housed in the lower housing 2A so as to be parallel to the inclined upper surface of the upper housing 2B, and is engaged with the printed circuit board 18; The screw attachment portion 17 is fixed to the inner surface of the upper housing 2B by a set screw 19, so that the upper surface of the frame 15 is brought into close contact with the inner surface of the upper housing 2B. Each of the partition plates 14A, 14B, and 14C is located between each row of the key tops 10a to 10l, and a pair of left and right pins 23 are integrally provided on the lower end surface of the partition plates 14A, 14B, and 14C, as shown in FIG. They are respectively inserted into small holes 24 formed in the printed circuit board 16.

Each of the key tops 10a to 10l is not directly connected to the frame 15, but is supported by a pair of left and right elastic support arms 25, 26 so as to be vertically movable. The pair of support arms 25 and 26 are curved almost symmetrically and surround the outer peripheries of the upper ends of the key tops 10a to 10l, and their bases are connected to the 15 side. In this case, a pair of left and right support arms 25, 2 respectively support three key tops 10b, 10c, 10d on which numbers 1 to 3 are displayed and arranged in a horizontal row.
6 extends from the inner surface of the rear plate 13c of the frame 13, and its free end is connected to the key top 10.
b, 10c, and 10d are connected to the circumferential surfaces on the side opposite to the rear plate 13c side. Therefore, each key top 10b, 10c, 10d is independent of each other, and when pressed, the pair of support arms 2
The supporting arms 25 and 26 are elastically deformed so as to be lowered, and when released from the external force, the support arms 25 and 26 are elastically restored and returned to the upper position. On the other hand, the second row key tops 10e, 10f, 10
g, 3rd row key tops 10h, 10i, 10j
and fourth row key tops 10k, 10a, 10
A pair of support arms 25, 2 each supporting l.
6 extends from the inner surface of each of the partition plates 14A, 14B, and 14C. The pair of support arms 25 and 26 intersect with the upper surface of the frame 15 at an appropriate angle Θ, for example, about 4 degrees, so that
Its free end, i.e. each keytop 10a-1
The joint side with 0l is raised above the upper surface of the frame 15.

As shown in FIG. 6, a recess 30 is formed in the lower end surface of each of the key tops 10a to 10l, and a protrusion 31 is protruded from approximately the center of the recess 30.
Each key top 1 is provided on the upper surface of the printed circuit board 18.
Push button switches 32 are provided corresponding to the projections 31 of 0a to 10l.

In such a configuration, the push button dial 4 is fixed to the inner surface of the upper housing 2B with a set screw 19, and the printed circuit board 1 is attached to the lower surface of the push button dial 4.
8 and then connect the upper housing 2B to the lower housing 2A, the push button dial 4 is accommodated in the telephone housing 2, and each key top 10 is assembled.
The upper end of a to 10l is the round hole 1 of the upper housing 2B.
1 to the outside. In this stored state, the inner surface of the upper housing 2B and the upper surface of the frame 15 are in close contact with each other. Therefore, all the support arms 25 and 26 that respectively support the key tops 10a to 10l are pressed by the inner surface of the upper housing 2B, and are elastically deformed as shown by the chain lines in FIG. It is flush with the upper surface, thereby making the protrusion dimensions of all the key tops 10a to 10l from the round hole 11 uniform. Also,
Since the support arms 25 and 26 are pressed against the inner surface of the upper housing 2B, each key top 10
The stability of the key tops 10a to 10l is good, and since the key tops 10a to 10l have a return habit due to their own elasticity, there is no need for a conventional spring, and the operation feeling of each key top 10a to 10l is improved. It can be arranged uniformly. Furthermore, even if there are variations in the manufacture and assembly of each switch 32, the upward escape of each key top 10a to 10l prevents the switch from remaining pressed, which is particularly effective for switches with small strokes. be. In that case, it is desirable that the return force of the switch 32 itself is greater than the return force of each key top 10a-10l.

Although the above embodiment has been described with reference to the case where it is applied to a push-button dial of a telephone, the present invention is not limited to this, and it goes without saying that the present invention can be implemented in operation buttons of various telephone devices.

〔Effect of the invention〕

As explained above, the structure of the key top according to the present invention integrally forms a frame, a key top spaced apart from the frame, and a pair of left and right support arms that have elasticity and support the key top in a vertically movable manner.
One end of the pair of support arms is connected to the frame, and the other end is connected to the circumferential surface of the key top on the side opposite to the frame side, and the key top side connecting portion is slightly raised above the top surface of the frame. Since the frame is pressed into contact with the inner surface of the casing, the key top can be stably supported, and a return spring is not required, resulting in a simple structure. In addition, even if multiple key tops are formed by integral molding, each key top can be made independent, providing excellent operability. When brought into contact with each other, the pair of support arms are elastically deformed to make the protruding dimensions of each key top uniform.Furthermore, variations in the switch can be absorbed by the upward escape of each key top. There is no need to keep pressing the switch, and it is particularly effective for switches with small strokes, and is suitable for implementation in push-button dials of telephones.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing an embodiment of the key top according to the present invention applied to a push-button dial of a home telephone, Fig. 2 is a plan view of the key top, Fig. 3 is a side view of the key top, and Fig. 4 5 is a sectional view of the elastic engagement piece, FIG. 5 is a side view of the partition plate, and FIG. 6 is a partially broken enlarged sectional view of the key top. 1...Home phone, 2...Telephone housing, 4...
Push-button dial, 10a-10l...key top, 13...frame, 14A, 14B, 14C...
Partition plate, 15...frame, 25, 26...support arm.

Claims (1)

[Claims] 1. In the structure of a key top that is assembled inside a housing and whose operation surface is exposed to the outside of the housing and is operated by pressing, the key top includes a frame, a key top that is separated from the frame, and a pair of left and right support arms that connect the key top and the frame. The pair of support arms each extend from the frame and have elasticity, and their free ends are joined at the peripheral surface of the key top on the side opposite to the frame. The structure of the key top is characterized in that the key top is raised slightly from the upper surface of the frame, the upper surface of the frame is brought into contact with the inner surface of the equipment casing, and the support arm is pressed against the inner surface of the equipment casing.