JP3225544B2 - Seesaw 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 seesaw switch used for an input operation unit of various electronic devices.

[0002]

2. Description of the Related Art FIG.
This will be described with reference to FIG. 9 is an external perspective view of a conventional seesaw switch, FIG. 10 is a sectional view thereof, FIG. 11 is an exploded perspective view showing its components, and FIG. 12 is a side sectional view showing an operation state thereof.

In FIGS. 9 to 12, reference numeral 1 denotes a frame-shaped insulating resin switch case having an upper and lower part penetrated, and a rectangular contact board 2 made of a copper-clad laminate closes the opening on the lower surface side. Mounted on On the upper surface of the contact board 2, two pairs of fixed contacts 3 (3A, 3B) and 4 (4A, 4B) made of copper foil are provided at symmetrical positions on the left and right, and each pair of A connection portion 5 electrically connected to the fixed contact is formed, and an external connection lead wire 7 passed through the through hole 6 from the lower surface side of the switch substrate 2 is connected by soldering.

Above the switch substrate 2, two contact domes 10 and 11 having movable contacts 8 and 9 corresponding to the fixed contacts 3 and 4 on the inside of each vertex are integrally formed. The contact rubber 12 having the following is fitted inside the switch case 1. Further, a seesaw button 13 is disposed on the upper surface side of the switch case 1 so as to close the opening, and a fulcrum 14 provided on the opposite wall surface of the switch case 1 at an intermediate position between the two sets of contacts 3 and 4. It is supported to be able to swing left and right. There are actuating projections 17 and 18 on the lower surfaces of the left and right push-down portions 15 and 16 of the seesaw button 13, and the lower ends thereof are at the apexes of the two contact domes 10 and 11 of the contact rubber 12. In contact.

In the switch having such a configuration, when a pressing force is applied to one of the pressing portions 15 of the seesaw button 13, the seesaw button 13 rotates leftward about the fulcrum 14, and an operating projection on the lower surface thereof. The portion 17 pushes down the contact dome 10 of the contact rubber 12 to deform the contact dome 10 as shown in FIG. 12 from the state of FIG. 3
A and 3B are short-circuited. At this time, this signal is
Is transmitted to the outside through

[0006] Then, the pressing portion 1 of the seesaw button 13
When the force applied to the contact 5 is removed, the deformed rubber contact dome 10 tries to return to its original state by its elastic restoring force, so that the movable contact 8 separates from the fixed contact 3 and the seesaw button 13
The switch returns to the original state in FIG. Similarly, seesaw button 13
When a pressing force is applied to the other pressing portion 16 of the other, the other fixed contact 4 can be brought into contact with and separated from the other.

[0007]

However, the conventional seesaw switch has the disadvantage that the number of components is large, the accuracy of the combination is poor, and the number of assembly steps is high, and the cost is high. there were. Another problem is that the height of the entire switch is large and it is difficult to reduce the size and thickness of the equipment used.

An object of the present invention is to solve these problems and to provide an inexpensive thin seesaw switch with a small number of components and a small number of assembling steps, high accuracy and high accuracy.

[0009]

In order to achieve the above object, a switch according to the present invention is provided with contacts facing each other at two predetermined points on an inner surface of an insulated flexible sheet which is folded back. A switch sheet in which a sheet on the upper surface side of the contacts is drawn into a dome shape having elasticity to provide a gap between the opposed contacts, and also integrally formed with a lead conductor for connecting the two sets of contacts to the outside. A switch case made of an insulating resin having a box-like shape having an upper surface opening, accommodating opposed contacts of the switch sheet on a bottom surface, and having a lead-out gap for a lead conductor at an end of the bottom surface; arranged so as to close the opening, it is held swingably by the fulcrum portion of the opposed wall surfaces of the switch case at an intermediate position of the two pairs of contact portions, the surface on the switch sheet And the lower surface side, Ri Do and a seesaw button having two actuation projection in contact with the upper surface of the dome-shaped portion of the two places, pairs on the bottom portion of the switch case
Cut parts are provided on three sides around the part where the contact
In addition to the cantilever-shaped part, this cantilever-shaped part
This is a seesaw switch divided into two parts.

[0010]

With this configuration, the fixed contact board portion of the switch is
Since the three functional parts of the movable contact dome and the external connection lead having elasticity are integrally formed, the number of components of the switch can be reduced, and the overall height of the switch is reduced. Can be. Ma
The cantilever is divided into multiple parts on the bottom of the switch case.
By providing a beam-shaped part, the movable contact opposed to the switch and the fixed contact
The number of points to which contact pressure between
Abnormal force is applied between the movable contact and the fixed contact
To prevent switch contact against dust etc.
It can be standardized.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

FIG. 1 is a side sectional view of a seesaw switch according to a first embodiment of the present invention, FIG. 2 is an external perspective view, FIG. 3 is an exploded perspective view showing its components, and FIG. FIG. 5 is a cross-sectional view illustrating an operation state of the switch sheet, which is an essential part, of the opening of the switch sheet.

In FIG. 1 to FIG. 5, reference numeral 21 denotes a box-shaped switch case made of an insulating resin having an upper surface opening, and a switch sheet 22 made of an insulating flexible sheet is accommodated on the inner bottom surface thereof.

As shown in FIG. 4, the switch sheet 22 is provided with a predetermined surface on a sheet 22A on the side that contacts the bottom surface of the lower switch case 21 of the opposed inner surfaces obtained by folding one elongated insulated flexible sheet. Two sets of fixed contacts 23A, 23B and 24A, 24B are provided at intervals, and these fixed contacts 23A, 2
Movable contacts 25 and 26 for short-circuiting between 3B and 24A, 24B are formed at predetermined positions by a method such as conductor printing, and are extended in a direction opposite to the folded portion of sheet 22A on the fixed contact side. The extension 22C has fixed contacts 23A, 23B, 24A, 24B of this switch.
Conductors 27A, 27B for connecting the leads to the outside
27C is formed by printing or the like. The extension portion 22C is led out through a gap 28 provided at the bottom end of the switch case 21.

The movable contact portions 25 and 26 on the surface of the folded sheet 22B are attached to the fixed contact side sheet 22A.
In order to keep a fixed gap with respect to the fixed contacts 23 and 24 when the layers are overlapped with each other, dome-shaped portions 25A and 26A having elasticity are formed by drawing. The fixed contact side sheet 22A and the folded sheet 22B
The switch sheet 22 is fixed to the bottom surface of the switch case 21 by crimping the dowels 21A on the bottom surface of the switch case 21 into the small holes 22D and 22E that have been drilled.

A seesaw button 29 is disposed so as to cover the opening on the upper surface of the switch case 21. The switch case 21 is opposed to the intermediate position between the two sets of fixed contacts 23, 24 (and the movable contacts 25, 26). The pivotal support by the fulcrum 31 provided on the wall surface is the same as in the conventional example, and the seesaw button 29 is also provided on the lower surfaces of the left and right push-down portions 32 and 33 with the operating protrusions 34. , 35, and the lower end of each is in contact with the apex of the dome-shaped portion 25A, 26A of the movable contact 25, 26.

The present invention is constructed as described above. When a pressing force is applied to one of the pressing portions 32 (or 33) of the seesaw button 29, the seesaw button 29 is moved to the left around the fulcrum 31. In the direction (or rightward), the operating projection 34 (or 35) on the lower surface pushes down the dome-shaped portion 25A (or 26A) of the folded sheet 22B downward and deforms as shown in FIG. The movable contact 25 (or 26) inside the fixed contact side sheet 22
A fixed contact 23A, 23B (or 24A, 24B
Short circuit).

At this time, this signal is transmitted to the lead conductors 27A, 27B (or 27A, 27C) of the extension sheet 22C.
Is transmitted to the outside through

Then, the pressing portion 3 of the seesaw button 29
2 (or 33), the dome portion 25A (or 26) of the folded sheet 22B that has been deformed is removed.
A), the movable contact 25 (or 26) separates from the fixed contact 23 (or 24) in an attempt to return to the original position by the elastic force, and the actuating projection 34 (or 35) of the seesaw button 29 is pushed back. The return of the switch to the original state is similar to the conventional example.

(Embodiment 2) Here, the pressing portion 32 (or 3) of the seesaw button 29 is pressed.
When a pressing force is applied to 3), the operating protrusion 34 (or 3) is used.
5) between the opposed movable contact 25 and the fixed contact 23 of the switch sheet (or the movable contact 26 and the fixed contact 24).
FIGS. 6 and 7 show a second embodiment of the present invention which takes care not to apply an unnecessarily large force to the contacts 23, 24, 25, and 26 so that the conductor printing is not scraped or deformed. This will be described with reference to FIG. FIG. 6 is an external perspective view of the switch case viewed from the bottom side, and FIG. 7 is a side sectional view showing an operation state of the switch.

As shown in FIGS. 6 and 7, the switch case 21 for accommodating the switch sheet 22 is formed of an elastic insulating resin. Cut portions 3 are provided on three sides around a portion where the movable contact 26 and the fixed contact 24 abut.
6 and 37 are provided as cantilever portions 38 and 39, and as shown in FIG.
Of the folded sheet 22B is pressed and deformed by the operating projection 34, and the movable contact 25 inside the folded sheet 22B is fixed to the fixed contact side sheet 2.
When a further pressing force is applied from a state in which the fixed contact 23 is in contact with the fixed contact 23 of 2A, the cantilevered portion 38 on the bottom surface of the switch case
Is deformed until the lower left end portion 32A of the seesaw button 29 hits the upper end of the switch case 21, thereby preventing an abnormal force from being applied between the movable contact 25 and the fixed contact 23.

Thereafter, when the pressing force applied to the seesaw button 29 is removed, the cantilever 38 returns to its original state by its elastic force.

(Embodiment 3) A further improvement of the second embodiment is the third embodiment shown in FIG. 8, and FIG. 8 is an external perspective view of the switch case viewed from the bottom side. Switch case 2 shown in FIG.
8 is divided into a plurality of flexible cantilever portions 38 (or 39) on the bottom surface portion of FIG.
(Or 39A, 39B,...), A contact pressure is applied between the movable contact 25 and the fixed contact 23 facing each other (or between the movable contact 26 and the fixed contact 24) of the switch. A plurality of points are used to stabilize switch contact against dust and the like.

The method of dividing the cantilever 38 (or 39) into a plurality is shown in FIGS. 8 (a), 8 (b) and 8 (c).
There is a method as shown in FIG.

[0025]

According to the present invention, as is apparent from the above-described embodiment, the fixed contact substrate portion of the seesaw switch, the movable contact dome portion having elasticity and the external connection lead portion are also formed from one insulating flexible sheet. And has the following effects.

(1) Since the number of switch components is small, deterioration of accuracy due to combination of components is small.

(2) Since the number of switch components is small, the number of assembling steps is small, which is advantageous in terms of cost.

(3) Since the components such as the movable contact dome portion and the fixed contact substrate are thin and the height of the entire switch can be reduced, it is very advantageous for miniaturization and thinning of the equipment used. is there.

(4) Even if a large external force is applied to the seesaw button portion of the switch, the contact portion can be protected and a stable contact can be obtained.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a seesaw switch according to a first embodiment of the present invention.

FIG. 2 is an external perspective view of the seesaw switch according to the first embodiment.

FIG. 3 is an exploded perspective view of the seesaw switch according to the first embodiment.

FIG. 4 is a perspective view of a switch sheet, which is an essential part of the seesaw switch according to the first embodiment.

FIG. 5 is a side sectional view illustrating the same operation state of the seesaw switch in the first embodiment.

FIG. 6 is an external perspective view of a switch case which is a main part of a second embodiment of the present invention.

FIG. 7 is a side sectional view illustrating an operation state of the second embodiment.

FIG. 8 is an external perspective view of a switch case which is a main part of a third embodiment of the present invention.

FIG. 9 is a perspective view of a conventional seesaw switch.

FIG. 10 is a side sectional view of a conventional seesaw switch.

FIG. 11 is an exploded perspective view of a conventional seesaw switch.

FIG. 12 is a side sectional view illustrating an operation state of a conventional seesaw switch.

[Explanation of symbols]

 Reference Signs List 21 switch case 22 switch sheet 23, 24 fixed contact 25, 26 movable contact 25A, 26A dome-shaped portion 27 lead conductor 29 seesaw button 31 fulcrum portion 32, 33 depressing portion 34, 35 operating protrusion 36, 37 cutting portion 38,39 Cantilever beam

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-62-295319 (JP, A) JP-A-52-74875 (JP, A) Fully open Showa 54-9975 (JP, U) 20830 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01H 23/02 H01H 23/30

Claims (1)

(57) [Claims] At least two opposing contacts are disposed at predetermined two points on an opposing inner surface obtained by folding one insulating flexible sheet, and the sheet on the upper surface side of the opposing contacts is drawn into a dome shape having elasticity. And a switch sheet integrally formed with lead conductors for connecting the two sets of contacts to the outside, and a box-shaped switch sheet having a top opening on the bottom surface. A switch case made of an insulating resin that accommodates the opposite contacts and has a lead-out gap at the bottom end for conducting the lead conductor,
The switch case upper surface opening is disposed so as to close the opening, and at the intermediate position between the two sets of contact points, it is swingably held by a fulcrum portion of the opposing wall surface of the switch case. Ri Do and a seesaw button having two actuation projection in contact with the upper surface of the dome-shaped portion of the position, the contacts facing the bottom portion of the switch casing abuts
If a cantilever is formed by providing cuts on three sides around the part
Both are seesaw switches in which this cantilever is divided into a plurality .