JP4090275B2 - Key top mounting structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a key top mounting structure in which a key top is installed on a film board such as a switch board having flexibility.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a switch mechanism in which a key top is installed on a switch board has a switch board 110 made of a film plate placed on a base 100 and a switch provided on the switch board 110 as shown in FIG. The key top 130 is installed on the reverse plate 121 of the contact 120. Here, the key top 130 is connected to the frame body 135 via a hinge 131 integrally formed therewith. When the key top 130 is pressed, the hinge 131 is bent and lowered, the reversing plate 121 is reversed and the switch contact 120 is turned on.
[0003]
However, in the switch mechanism having the above structure, since the hinge 131 is made of molded resin, a predetermined length is necessary for the hinge 131 to be easily bent. Therefore, the switch mechanism cannot be downsized. Since durability is necessary and it cannot be made so thin, there is a limit to reducing the thickness of the switch mechanism.
[0004]
Therefore, as shown in FIG. 6, the hinge 131 is replaced with a flexible resin film hinge plate 137, and a switch mechanism configured to connect the key top 130 and the frame body 135 with the hinge plate 137 is also available. It is considered. With this configuration, even if the distance between the key top 130 and the frame body 135 is short, the hinge plate 137 can be easily bent and the thickness thereof is thin, so that the switch mechanism can be reduced in size and thickness.
[0005]
However, since this switch mechanism requires the hinge plate 137, the number of parts increases and the part cost increases. Further, there has been a demand for further downsizing and thinning of the switch mechanism.
[0006]
[Problems to be solved by the invention]
The present invention has been made in view of the above points, and an object of the present invention is to provide a key top mounting structure capable of reducing the number of parts and reducing the size and thickness.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the key top mounting structure according to the present invention has a flexible film plate provided with a bending portion, and fixed side members on which the film plate is placed on both sides of the bending portion of the film plate. The center of the flexure is fixed so that the center of the flexure protrudes upward, and the keytop is attached to the midway part of the flexure that is deflected upward. It is characterized by being supported so as to be movable up and down.
[0008]
Further, the present invention is characterized in that the switch mechanism is configured by providing a switch contact on the film plate and installing a pressing portion of a key top attached to the bending portion so as to face the switch contact.
[0009]
As a result, this structure can be easily made by sharing a mechanical hinge and an electric circuit board with a single film plate.
[0010]
In particular, it is preferable that the bent portions are provided on both side portions of the switch contact, the key top is attached to both the bent portions, and the pressing portion is provided between both the attached portions of the key tops.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is an exploded perspective view showing a switch mechanism using a keytop mounting structure according to an embodiment of the present invention. As shown in the figure, this switch mechanism is configured by attaching a film plate 20, a reversing plate 50, and a key top 60 on a fixed side member (hereinafter referred to as “mounting base”) 10. Each component will be described below.
[0012]
The mounting base 10 is made of a rigid synthetic resin plate, and is provided with four small protrusion-shaped fixing portions 11, 12, 13, and 14 at predetermined positions.
[0013]
The film plate 20 is configured by providing a switch contact S on the upper surface of a flexible synthetic resin film (for example, polyethylene terephthalate film) 21 and providing a pair of flexures 31 and 37 on both sides of the switch contact S. ing. The switch contact S includes a central contact pattern S1 and a ring-shaped contact pattern S2 surrounding the periphery. Drawing patterns 23 and 27 are drawn from both contact patterns S1 and S2, respectively. The insulating pattern 25 is put on the portion of the drawing pattern 23 drawn from the contact pattern S1. The flexures 31 and 37 are formed in a band shape by cutting the film 21 into a substantially “U” shape so that one end (tip) thereof becomes a free end a1 and the other end (end) becomes a fixed end a2. It is configured. Attachment portions 33, 35, 39, and 41 each having a small hole are provided at the distal end and the central portion of each of the bending portions 31 and 37, respectively. On the other hand, attachment portions 43 and 45 having small holes are also provided at predetermined positions other than the bending portions 31 and 37 of the film 21.
[0014]
In this embodiment, the reversing plate 50 is a movable contact plate, and an elastic metal plate is formed in a dome shape, and the outer periphery thereof is formed to have a size to be placed on the contact pattern S2.
[0015]
The key top 60 is formed by molding a synthetic resin into a substantially disk shape, and a pressing portion 61 that presses the reversing plate 50 is provided at the center of the lower surface, and small protrusions are formed on both sides of the pressing portion 61. Fixed portions 63 and 65 are provided.
[0016]
In order to assemble this switch mechanism, first, the reverse plate 50 is attached on the contact pattern S2 of the film plate 20. Next, the key top 60 is placed on the film plate 20, and in this case, both the fixing parts 63 and 65 provided on the key top 60 are inserted into the attachment parts 35 and 41 provided on the both bending parts 31 and 37, and the back surface thereof. Secure with heat caulking on the side. Next, the film plate 20 is placed on the mounting base 10, and the fixing portions 11, 12, 13, 14 of the mounting base 10 are inserted into the mounting portions 33, 39, 43, 45 of the film plate 20. Fix the tip by caulking the tip. Thereby, the switch mechanism shown in FIG. 2 is completed.
[0017]
FIG. 3 is a perspective view showing a state in which the key top 60 is removed from the assembled switch mechanism. As shown in FIG. 3, both the bending parts 31 and 37 are being fixed to the mounting base 10 in the state bent in the arc shape to the upper direction. In other words, the film plate 20 is fixed on the mounting base 10 by the fixing portions 13 and 14, whereby the positions of the fixed ends a2 and a2 of the bending portions 31 and 37 on the mounting base 10 are fixed, while the free ends a1 and a2 are fixed. By fixing the fixed position of a1 slightly shifted to the fixed ends a2 and a2 side, both the bent portions 31 and 37 are bent upward.
[0018]
4 is a cross-sectional view of the switch mechanism shown in FIG. As shown in FIG. 4, the key top 60 is installed so as to be positioned slightly above the switch contact S provided on the film plate 20 by the bending portion 31 (37). At this time, the pressing portion 61 of the key top 60 is the reversing plate. 50 abuts. Then, if the key top 60 is pressed, the bending portion 31 (37) is lowered by being deformed, and the pressing portion 61 presses the reversing plate 50 and reverses it, and between the contact patterns S1, S2 of the switch contact S. Turn on. When the pressure on the key top 60 is released, the key top 60 automatically returns to the original position and the switch contact S is turned off by the elastic return force of the bending portion 31 (37) and the elastic return force of the reversing plate 50.
[0019]
FIG. 7 is an exploded perspective view showing a switch mechanism using a keytop mounting structure according to another embodiment of the present invention, and FIG. 8 is a perspective view showing the assembled switch mechanism. In this switch mechanism, the same or corresponding parts as those of the switch mechanism are denoted by the same reference numerals, and detailed description thereof is omitted. This switch mechanism is also configured by attaching a film plate 20, a reversing plate 50, and a key top 60 on a fixed side member (hereinafter referred to as “mounting base”) 10.
[0020]
In this embodiment, the difference from the previous embodiment is the structure of the film plate 20. That is, in the film plate 20 of this embodiment, a flexible synthetic resin film 21 is provided with two surfaces (a switch contact forming surface 28 and a bent portion forming surface 29), and both the surfaces 28 and 29 are bent. It is the point which comprised in the structure bent at a part. The switch contact forming surface 28 is provided with mounting portions 47, 48, 49 made of three small holes, and the bending portion forming surface 29 is also provided with mounting portions 51, 52, 53 made of three small holes. By providing holes (may be cutouts) 54 inside the bent portion forming surface 29, the band-like portions on both sides thereof are set as the bent portions 31 and 37. Mounting portions 35 and 41 are provided in both the bending portions 31 and 37. The distance L2 between the mounting portions 51, 52 of the bent portion forming surface 29 and the mounting portion 53 is slightly longer than the distance L1 between the mounting portions 47, 48 of the switch contact forming surface 28 and the mounting portion 49. (L1 <L2).
[0021]
Then, the key top 60 is attached to the lower surface side of the bent portion forming surface 29 in the same manner as in the above embodiment, the reversing plate 50 is attached to the switch contact S, and the switch contact forming surface 28 is placed on the mounting base 10. The fixing portions 11, 12, and 13 provided on the mounting base 10 are inserted into the mounting portions 47, 48, and 49, and the bending portion forming surface 29 is folded back on the switch contact forming surface 28 as shown in FIG. If the fixing portions 11, 12, 13 are inserted into the attachment portions 51, 52, 53 and the tips of the fixing portions 11, 12, 13 are caulked, this switch mechanism is completed. At this time, since there is a relationship of L1 <L2, the bending portions 31 and 37 bend upward.
[0022]
If comprised in this way, the external dimension of the film board 20 which attaches the key top 60 can be further reduced in size.
[0023]
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the technical idea described in the claims and the specification and drawings. Is possible. Note that any shape, structure, or material not directly described in the specification and drawings is within the scope of the technical idea of the present invention as long as the effects and advantages of the present invention are exhibited. For example, in the above embodiment, a pair of flexures is provided, but one or three or more may be provided.
[0024]
In the above embodiment, the film plate 20 is configured as a switch substrate by providing the switch contact S on the film plate 20. However, the switch contact S is not necessarily provided on the film plate 20, and it is separately provided below the film plate 20. By disposing a switch board or the like, the film plate 20 may have only a holding function for fixing the key top 60 to be movable up and down. Moreover, in the said embodiment, although the reverse plate 50 was installed on the switch contact S and the switch was comprised, you may abbreviate | omit the reverse plate 50 depending on the case. In that case, a switch is configured by providing a conductive layer on the lower surface of the pressing portion 61 of the key top 60. Depending on the structure of the switch, the reversing plate 50 may be used as a click plate instead of a movable contact plate.
[0025]
【The invention's effect】
As described above in detail, the present invention has the following effects.
(1) Since the key top mounting structure can be configured simply by fixing the key top to the bending portion provided on the film plate, the structure and assembly are simple, and the number of parts can be reduced.
[0026]
{Circle around (2)} Since the bent portion is located below the key top, the size can be reduced.
[0027]
(3) The bending portion is a part of the film plate and can be formed thin, so that the thickness can be reduced.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view showing a switch mechanism using a keytop mounting structure according to an embodiment of the present invention.
FIG. 2 is a perspective view of a switch mechanism.
FIG. 3 is a perspective view showing a state in which a key top 60 is removed from a switch mechanism.
4 is a cross-sectional view of the switch mechanism shown in FIG. 2 taken along the line AA.
FIG. 5 is a view showing a conventional switch mechanism.
FIG. 6 is a view showing a conventional switch mechanism.
FIG. 7 is an exploded perspective view showing a switch mechanism using a keytop mounting structure according to another embodiment of the present invention.
8 is a perspective view showing a state where the switch mechanism shown in FIG. 7 is assembled. FIG.
[Explanation of symbols]
10 Mounting base (fixed side member)
11, 12, 13, 14 Fixed part 20 Film plate 21 Film S Switch contact S1, S2 Contact pattern 23, 27 Draw pattern 31, 37 Deflection part a1 Free end a2 Fixed end 33, 35, 39, 41, 43, 45 Mounting 50 Reversing plate 60 Key top 61 Pressing part

Claims (2)

A flexible film plate is provided with a bending portion, and a portion on both sides of the bending portion of the film plate is projected on the fixed side member on which the film plate is placed so that the center of the bending portion protrudes upward. Key top mounting, characterized in that the key top is supported on the film plate so as to be movable up and down by fixing and attaching the key top to the middle part of the bent portion that is bent upward and protruding. Construction.   2. The key top according to claim 1, wherein the film plate is provided with a switch contact, and a switch mechanism is configured by installing a pressing portion of the key top attached to the bent portion so as to face the switch contact. Mounting structure.

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