JP3368405B2 - Key top for push button 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 key top for a push button switch.

[0002]

2. Description of the Related Art Conventionally, for a push button switch having a structure in which a key top is arranged between a substrate and a case, and the push button switch provided on the substrate is turned on / off by pressing the key top. There is a key top.

In this type of push button switch key top, hinges are projected from both sides of the key top for surely maintaining the disposition position at a fixed position, and the tips of both hinges are supported by other members. Is being done.

FIG. 5 is a perspective view showing a conventional key top for a push button switch of this type. As shown in the figure, the key top 91 is constructed by projecting two hinges 92, 93 from both sides thereof and fixing the tips thereof to the surrounding frame bodies 94, 95.

However, a key top 9 of this kind of structure
In the case of 1, since the frame bodies 94 and 95 must be provided on both sides of the key top 91, electronic parts cannot be mounted on the portion of the substrate on which the frame bodies 94 and 95 are mounted. Therefore, space saving and downsizing cannot be achieved.

Also, hinges 92,
Since 93 is attached and the tip thereof is fixed to the frame bodies 94 and 95, when the key top 91 is pressed, the key top 91 is pulled by both hinges 92 and 93 from both sides thereof, and generally the hinge 92, The rigidity of 93 becomes too strong, and the operation of pressing the key top 91 becomes heavy. Therefore, conventionally, the strength has been weakened by making the hinges 92, 93 extremely thin or thin.

However, according to the above method, the hinges 92, 93
If the strength of the key top 91 is weakened, it becomes difficult to support the key top 91 so that it swings only in a certain direction, and the key top 91 swings in all directions depending on the position where the key top 91 is pressed. It may not be possible to smoothly turn on / off the switch provided at one place below.

If the strength of the hinges 92 and 93 is weakened, permanent deformation of the hinges 92 and 93 is likely to occur, which may lead to malfunction.

The present invention has been made in view of the above points, and an object thereof is to provide a key top having a structure in which hinges are attached to both sides of the key top, while maintaining the strength of the hinge and smoothly pressing the key top. Another object of the present invention is to provide a key top for a push button switch, which can be realized in a space-saving and compact size.

[0010]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention is to mount a push button switch on a substrate, and to provide a pressing portion for pressing the push button switch at a position facing the push button switch. In the key top for a push button switch, from the side near the end of the key top,
On both sides in the direction substantially perpendicular to the straight line connecting the vicinity of the section and the pressing section
Two hinges are installed to support and project in a substantially straight line toward
Only, one end of the hinge of the key top is supported by and fixed to the other member, the other hinge tip substrate protrusion of the lower end provided with projections directed downwardly to the free end and then and tip Or, it is decided to support it by abutting it on another base.

[0011]

The key top is supported by the pressing portion for pressing the push button switch and the three points of the tips of both hinges. When the key top is pressed, both hinges are bent and the key top swings, and the pressing portion turns on the push button switch. Here, since the tip of one of the hinges is set as a free end and the projection provided at the tip is brought into contact with the board or other base, the projection is provided on the board or other base when the key top is swung. Move freely on top. Therefore, even if the strength of the hinge is increased, sufficient elasticity can be obtained and the key top can be pressed smoothly.

[0012]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is an exploded perspective view showing a state in which a key top body 10 for a push button switch according to an embodiment of the present invention is housed between a substrate 30 and a case 50. 2 is a perspective view of the key top body 10 as viewed from the back side.

As shown in FIGS. 1 and 2, this key top body 10 has a ring-shaped groove 1 on the outer circumference of a circular key top 11.
3, a circular recess 15 is provided at the center of the lower surface of the key top 11, and a recess 1 on the lower surface of the key top 11 is provided.
A pressing portion 17 is projected downward from the periphery of 5.

Three protective projections 19 project downward from three locations around the recess 15 on the lower surface of the key top 11.

On the other hand, from the side portion near the end portion on the opposite side of the portion of the key top 11 where the pressing portion 17 is provided, on both sides in a direction substantially perpendicular to the straight line f connecting the end portion and the pressing portion 17. Two plate-shaped hinges 21 and 23 are projected in a substantially straight line. In other words, these hinges 21 and 23 are projected in a substantially straight line shape in the direction along the outer side S of the substrate 30 on which the key top 11 is placed.

One of the hinges 21 and 23 has one hinge 21 connected and fixed to the frame 25, and the other hinge 23 is a free end, and the projection 2 extends downward at its tip.
7 is provided. The lower end of the protrusion 27 projects below the lower end of the protection protrusion 19.

Here, the frame 25 is provided with two through holes 26, 26 penetrating in the vertical direction. An arm 28 is further attached to the frame 25, and other key tops or the like are attached to the tip of the arm 28.
It is omitted in the figure.

Each member constituting the key top body 10 is integrally molded with a thermoplastic polycarbonate resin made of a light-transmitting material.

Next, as shown in FIG. 1, the substrate 30 is provided with a desired wiring pattern (not shown) on the lower surface of a narrow narrow plate-shaped hard insulating substrate 31, while the light emitting element 33 is provided on the upper surface thereof. The push button switch 35 is attached and connected to the wiring pattern on the lower surface. Various electronic components other than the above are mounted on the substrate 30, but they are omitted from the drawing.

Here, the light emitting element 33 is arranged substantially at the center in the width direction of the substrate 30, and the push button switch 35 is arranged near one outer side P of the substrate 30.

Next, as shown in FIG. 1, the case 50 is provided with a circular hole 51 penetrating the key top 11 of the key top body 10, and from the lower surface thereof, the through holes 26 of the frame body 25, Two protrusions 53, 53 to be inserted into the 26 are provided. A side wall 55 is provided around the lower surface of the case 50. A projecting portion 57 that projects in a cylindrical shape is provided on the lower surface of the inner periphery of the hole 51.

To assemble these parts, first, the key top body 10 is attached to the lower surface of the case 50.
At this time, the two through holes 2 provided in the key top body 10
Two projections 53, 53 provided on the case 50 inside the 6, 26
Insert the key top 11 into the hole 51 of the case 50 at the same time.
Insert inside. Then, the tips of the protrusions 53, 53 are attached to the frame 25.
Fix both by heat staking on the underside of.

Next, the case 50 to which the key top body 10 is fixed is placed on the substrate 30, and the case 50 and the substrate 3 are placed.
The space between 0 is fixed by a fixing means (not shown). The cross section at this time is shown in FIG. As shown in FIG.
Is located substantially in the center of the recess 15 of the key top body 10, and the operating portion 36 of the push button switch 35 abuts on the pressing portion 17,
Further, the lower end of the protrusion 27 of the key top body 10 is the substrate 3
Abut on 0. At this time, the lower ends of the protection protrusions 19 of the key top body 10 are both separated from the substrate 30 by a predetermined distance.

As described above, the two hinges 21 and 23 are
From the side portion near the end portion on the opposite side of the portion of the key top body 10 where the pressing portion 17 is provided, from the side portion near the end portion and the pressing portion 17 to the straight line f substantially perpendicular to both sides in the substantially vertical direction. Since the hinges 21 and 23 are provided so as to project like a circle, the directions of the hinges 21 and 23 can be arranged along the outer side S of the substrate 30. Therefore, the widths L (see FIG. 3) of the case 50 and the substrate 30 are not increased by these hinges 21 and 23.

At this time, as shown in FIG. 3, the protrusion 5 provided on the case 50 is provided in the groove 13 provided on the key top 11.
7 is inserted to prevent water droplets from entering between the hole 51 of the case 50 and the key top 11 from entering the inside.

Next, the operation of the key top body 10 will be described. Here, FIG. 4 is a perspective view showing an arrangement position of the key top body 10 with respect to the substrate 30 when assembled.

As shown in FIG. 3 and FIG. 3, the key top 11
Is supported by the pressing portion 17 that comes into contact with the push button switch 35 and the three points of both tips of both hinges 21 and 23.

When the center of the key top 11 is pressed (arrow A shown in FIG. 4), the hinges 21 and 23 are substantially linear.
The key top 11 swings about the swing center axis, and the pressing portion 17 turns on the push button switch 35.

At this time, the tip of one of the hinges 23 is a free end, and the projection 27 provided at the tip of the hinge 23 is in contact with the substrate 30. Therefore, when the key top 11 is swung, the hinge 27 is moved in accordance with the swing amount. The protrusion 27 freely moves on the substrate 30. Therefore, at this time, the tension in the longitudinal direction of both hinges 21 and 23 does not work, and therefore, even if the strength of both hinges 21 and 23 is strong, sufficient elasticity is obtained and the key top 11 can be pressed smoothly.

When the pressing is released, both hinges 21, 23
By the elastic return force of the push button switch 35 and the return force of the push button switch 35 itself, the key top 11 returns to the original position, and the push button switch 35 is turned off.

On the other hand, when the light emitting element 33 is turned on to emit light, most of the light is introduced into the concave portion 15 of the key top 11 and the key top 11 is brightly illuminated from the back side thereof.

By the way, in FIG. 4, when the biased portion, for example, the arrow B or C portion, is pressed without pressing the center of the key top 11, the key top 11 is abnormally inclined in the direction of the pressed portion. There is a risk that However, in the case of the above-described embodiment, since the protective projection 19 is provided on the lower surface of the key top 11, the protective projection 19 abuts on the substrate 30 before the key top 11 is abnormally tilted, and such a phenomenon is prevented. is doing.

By the way, according to the present invention, since the protrusion 27 is supported by abutting it on the substrate 30 with the tip of the hinge 23 as a free end, a member such as a frame for fixing the hinge 23 is not required, As a result, more electronic components can be mounted on the substrate 30 and integrated, and space saving and downsizing can be achieved.

The hinges 21 and 23 are connected to the key top 11
The position of projecting from the outer peripheral side portion of is not limited to the above-mentioned embodiment, and may be projected from the center of the key top, for example. Moreover, both hinges 21 and 23 do not need to be linear, and may be curved. Also, the protrusion provided at the free end of the hinge does not necessarily have to abut on the substrate,
You may make it contact | abut on other bases (for example, hard resin plate) other than a board | substrate.

[0035]

As described above in detail, according to the present invention, although the key top has a structure in which hinges are attached to both sides, a protrusion provided at the tip of one of the hinges as a free end. Since the abutment is made on the substrate, sufficient elasticity can be obtained even if the strength of both hinges is increased, and the key top can be pressed smoothly.

Further, even though the key top has a structure in which hinges are attached to both sides, since the tip of one of the hinges is a free end, the supporting structure of the key top can be simplified,
Space saving and downsizing can be achieved.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a state in which a key top body 10 for a push button switch according to an embodiment of the present invention is housed between a substrate 30 and a case 50.

FIG. 2 is a perspective view of the key top body 10 as viewed from the back surface side.

FIG. 3 is a cross-sectional view when the key top body 10 is incorporated between a case 50 and a substrate 30.

FIG. 4 is a perspective view showing an arrangement position of a keytop body 10 with respect to a substrate 30.

FIG. 5 is a schematic side sectional view showing a structure of a conventional key top for a push button switch.

[Explanation of symbols]

10 key top body 11 key tops 15 recess 17 Pressing part 21,23 hinge 27 protrusions 30 substrates 33 light emitting device 35 push button switch 50 cases

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Claims (2)

(57) [Claims] 1. A key top for a push button switch, which is mounted on a substrate having a push button switch mounted thereon and has a pressing portion for pressing the push button switch at a position facing the push button switch, in the vicinity of an end portion of the key top. From the side of the
Approximately perpendicular to both sides of the straight line connecting the pressing part
Two hinges that project linearly and are supported are provided, one hinge end of the keytop is fixed to and supported by another member, and the other hinge has a free end and a downward direction at the free end. A key top for a push-button switch, characterized in that a protrusion directed toward the front side is provided, and a lower end of the protrusion is brought into contact with and supported on a substrate or another base. 2. A light emitting element and a push button switch are mounted on a substrate, and a recess for introducing light emitted from the light emitting element is provided at the center of the lower surface of the substrate, and the push button switch is provided around the recess on the lower surface. In a key top for a push button switch made of a translucent material having a pressing portion for pressing the push button switch at a position, from the side portion near the end portion on the side opposite to the portion where the pressing portion of the key top is provided, Two hinges are provided that project and support in a substantially linear shape toward both sides in a substantially vertical direction with respect to a straight line connecting the vicinity of the end portion and the pressing portion, and one end portion of one hinge is fixed to another member. The push button switch is characterized in that the other hinge has a free end at the other end, and a protrusion directed downward is provided at the end and the lower end of the protrusion is brought into contact with and supported by a substrate or another base. Key top for.