JPH0548159U - Membrane switch - Google Patents

Abstract

(57) [Summary] [Purpose] To facilitate the fixing of the movable push plate of the membrane switch and improve workability during assembly. [Structure] The insulating sheet 18 is provided with openings 20, 20 facing each other so that both sides of the hemispherical movable push plate 17 are exposed. Then, the strip portion 21 between the openings 20 and 20
Then, the movable push plate 17 is fixed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a membrane switch, and more particularly to a membrane switch provided with a movable push plate made of a hemispherical metal.

[0002]

[Prior Art]

 A conventional membrane switch of this type is shown in FIG. A spacer 3 is interposed between an upper film 1 and a lower film 2 of polyester or the like, and a gap portion 4 is provided, and contacts 5 and 6 are provided to face the gap portion 4. A movable pressing plate 7 made of a hemispherical metal is provided on the outer side of the upper film 1, and an insulating sheet 8 is attached and fixed so that the movable pressing plate 7 is not displaced. Further, a key top 9 is provided above the movable push plate 7 so as to be movable up and down, and by pressing the key top 9, the insulating sheet 8 and the movable push plate 7 are pressed downward, and the contact 5 of the upper film 1 and the bottom It is configured to make contact with the contact 6 of the film 2.

[0003]

[Problems to be solved by the device]

 In the conventional membrane switch described above, the movable push plate 7 is fixed by the insulating sheet 8. However, in order to release the air when the movable push plate 7 is pressed, a hole (Fig. Open (not shown). Alternatively, the movable push plate 7 is exposed and fixed with an adhesive tape or the like. In any of the configurations, the assemblability is not good, and it is necessary to bleed air when the movable push plate 7 is fixed.

Therefore, there arises a technical problem to be solved in order to facilitate the fixing of the movable push plate and improve the assemblability of the membrane switch. The present invention aims to solve this problem. .

[0005]

[Means for Solving the Problems]

 This invention has been proposed in order to achieve the above object, and a contact is made to face each other by providing a gap between films of polyester or the like, and a movable pusher made of a hemispherical metal is provided on the outside of the film on one side of the contact portion. In a membrane switch in which a plate is provided, an insulating sheet is attached and the movable push plate is fixed, and the movable push plate part can be tapped with a key top, the movable push plate part of the insulating sheet is A membrane characterized in that openings are provided so that both sides of the plate are exposed to face each other, and a band-like portion is provided between the openings to cover and fix the central portion of the movable pressing plate with an insulating sheet. The present invention provides a membrane switch characterized in that a movable pressing plate is exposed by opening an opening at a position where a key top of a strip-shaped insulating sheet between the openings comes into contact.

[0006]

[Action]

 The insulating sheet for fixing the hemispherical metal movable push plate is provided with an opening, and the movable push plate is fixed by the strip portion between the openings. Therefore, when the key top is pushed down to press the movable push plate, the air inside the movable push plate is discharged to the outside from the opening of the insulating sheet.

Further, when the movable pressing plate is exposed by forming an opening hole in the strip-shaped portion of the insulating sheet, it is considered that the insulating sheet does not come into contact when the key top is pushed down and the insulating sheet deteriorates. However, since the key top and the insulating sheet do not come into contact with each other, the insulating sheet will not be damaged.

[0008]

【Example】

 An embodiment of the present invention will be described in detail below with reference to FIGS. For convenience of explanation, the same components as those of the conventional one will be described at the same time. 1 and 2 show a membrane switch according to an embodiment of the invention as defined in claim 1, in which a spacer 13 is interposed between an upper film 11 and a lower film 12 made of polyester or the like to form a gap. A portion 14 is provided, and contacts 15 and 16 are provided in the gap portion 14 so as to face each other. A movable pressing plate 17 made of a hemispherical metal is provided outside the upper part of the upper film 11, and an adhesive portion 19 of an insulating sheet 18 is attached.

Opening portions 20, 20 exposing both sides of the movable push plate 17 are provided facing the movable push plate 17 of the insulating sheet 18. The adhesive portion 19a of the strip-shaped portion 21 between the openings 20 and 20 adheres from one side of the central portion of the movable push plate 17 to the other and covers the central portion of the movable push plate 17. , The movable push plate 17 is prevented from moving and fixed.

Although not shown, an opening is formed so that the central portion of the movable push plate 17 is exposed, and both side portions of the movable push plate 17 are adhered by the adhesive portions 19 of the insulating sheet 18 so that the movable push plate 17 can be moved. It may be fixed so as to prevent the push plate 17 from moving. Here, the contacts 15 and 16 are formed of silver electrodes, respectively, and the periphery thereof is covered with carbons 22 and 23 to prevent oxidation. Further, the contacts 15 and 16 are connected to other circuits by wiring patterns 24 and 25.

A key top 26 is provided above the strip-shaped portion 21 of the insulating sheet 18 so as to be movable up and down, and when the key top 26 is pressed, the lower end surface 26a of the key top is lowered, and the strip shape of the insulating sheet 18 is formed. The central portion of the portion 21 and the movable push plate 17 is pushed down. Therefore, the central portion of the movable push plate 17 presses the upper film 11, and the contact point 15 of the upper film 11 and the contact point 16 of the lower film 12 come into contact with each other.

If the key top 26 is moved upward, the movable push plate 17 and the insulating sheet 18 are restored to their original shapes by the repulsive force of the movable push plate 17, and the contact point 15 of the upper film 11 and the lower film 12 are returned. The contact 16 of is also separated. Further, the folded portion 27 may be provided on the outer peripheral edge of the movable push plate 17, and in such a case, damage to the upper film 11 and the insulating sheet 18 due to the concavo-convex action of the movable push plate 17 can be reduced. Naturally, the folded-back portion 27 is also effective for a structure in which the entire surface of the movable pressing plate 17 is covered with the conventional insulating sheet. Further, although not shown, if a concave portion is provided at the center position of the movable push plate 17, the movable push plate 17 is pressed more strongly than the upper film 11 when pressed, and the contacts 15 and 16 can be brought into good contact with each other.

FIG. 3 and FIG. 4 show an embodiment of the invention according to claim 2, in which an opening hole 28 is opened at a portion of the strip-shaped portion 21 of the insulating sheet 18 where the lower end surface 26 a of the key top abuts. is there. In such a case, when the key top 26 is hit, the lower end surface 26a of the key top does not contact the insulating sheet 18 and directly presses the movable push plate 17. Therefore, there is no possibility that the insulating sheet 18 deteriorates and the band-shaped portion 21 is cracked or cracked.

It should be noted that the present invention can be variously modified without departing from the spirit of the present invention, and it goes without saying that the present invention covers the modified version.

[0015]

[Effect of the device]

 Since the present invention is configured as described in detail in the above embodiment, it becomes easy to fix the movable push plate, and it is necessary to perform special air bleeding when attaching the movable push plate or to attach a separate adhesive tape. There is no. Therefore, the number of parts is reduced to reduce the cost and the workability at the time of assembly can be improved.

[Brief description of drawings]

FIG. 1 is a plan view of an essential part of a membrane switch showing an embodiment according to claim 1 of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a plan view of a main part of a membrane switch showing an embodiment according to claim 2 of the present invention.

FIG. 4 is a sectional view taken along line BB of FIG.

FIG. 5 is a vertical cross-sectional view of a conventional membrane switch.

[Explanation of symbols]

 11 Upper Film 12 Lower Film 13 Spacer 14 Gap 15, 16 Contact 17 Movable Push Plate 18 Insulation Sheet 20 Opening 21 Strip-shaped Part 26 Key Top 28 Opening Hole

Claims (2)

[Scope of utility model registration request] 1. A movable pressing plate made of a hemispherical metal is provided outside a film on one side of the contact portion with a gap provided between films of polyester or the like, and an insulating sheet is attached to the movable pressing plate. In the membrane switch in which the plate is fixed and the movable push plate portion can be tapped with the key top, the movable push plate portion of the insulating sheet is provided with the opening portions where both sides of the movable push plate are exposed facing each other. The membrane switch is characterized in that a band-shaped portion is provided between the openings and an insulating sheet covers and fixes the central portion of the movable pressing plate. 2. The membrane switch according to claim 1, wherein a movable pressing plate is exposed by forming an opening hole at a portion of the strip-shaped insulating sheet between the openings where the key tops come into contact.