JP2003007168A - Push-button switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure of a push-button switch which can secure an operation stroke of a movable contact, and of which the housing outline can be made small. SOLUTION: This push-button switch comprises a plurality of arm parts 5b extending continuously in the crossing directions from a reversible expanded part 5a in a domy movable contact 5, housing recessed parts 1c formed at four corners on diagonal lines of a housing 1 for housing in a bendable manner each arm part 5b of movable contacts 5 connected to a housing part 1a, and one or more circumferential fixed contacts 2c for having a contact always with the arm part 5b are arranged in the recessed part 1c.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a push button switch in which a dome-shaped movable contact is reversed by being pressed to bring the contact into and out of contact, and more particularly to an arrangement structure of the dome-shaped movable contact.

[0002]

2. Description of the Related Art The structure of a conventional push button switch is shown in FIGS. FIG. 12 is a plan view of the push button switch, and FIG.
[FIG. 3] is a vertical sectional view of a push button switch.

The conventional push button switch has a rectangular housing 11 having a housing 11a, a central fixed contact 12a, a first peripheral fixed contact 12b and a second peripheral fixed contact arranged in the housing 11a of the housing 11. 12c, a lower movable contact 14 arranged on the central fixed contact 12a and the first peripheral fixed contact 12b, and an upper movable contact 15 arranged on the lower movable contact 14 and the second peripheral fixed contact 12c. , A cover sheet 17 mounted on the upper surface of the housing 11 while covering the storage portion 11a, and a frame 18.

The housing 11 is formed of an insulating material such as synthetic resin into a rectangular box shape, and has a circular storage portion 11a inside. A central fixed contact 12a made of a conductive metal material is disposed at the center of the storage portion 11a so as to be exposed on the inner bottom surface.
A first peripheral fixed contact 12b, which is also made of a conductive metal material, is disposed on the outer side of a so as to project further from the central fixed contact 12a. Further, outside the first peripheral fixed contact 12b, a second peripheral fixed contact 12c, which is also made of a conductive metal material, is arranged so as to project further one step.

The lower movable contact 14 is formed of a conductive metal plate in a circular shape having a small diameter, and is formed in a dome shape having a reversible bulging portion 14a in the center. Also,
The upper movable contact 15 is also formed of a conductive metal plate in the shape of a circular dome having a reversible bulge 15a in the center, and its outer diameter is larger than that of the lower movable contact 14. It is formed to have a diameter.

The lower movable contact 14 is connected to the storage portion 11a.
In the case of accommodating in the above, the center of the bulging portion 14a is arranged so as to face the central fixed contact 12a arranged in the accommodating portion 11a,
The peripheral edge of the lower movable contact 14 is placed in contact with the first peripheral fixed contact 12b. At this time, the annular inner wall 11 protruding along the outer periphery of the lower movable contact 14 is housed in the storage portion 11a.
b is formed. The outer peripheral portion of the lower movable contact 14 is directly caulked and fixed by deforming the inner wall 11b of the housing portion 11a of the housing 11 inward.

The lower movable contact 1 is fixed by caulking the outer peripheral portion of the lower movable contact 14 to the housing 11.
The peripheral portion of 4 is always in contact with the first peripheral fixed contact 12b, and the lower movable contact 14 can be used as a conduction path for switching with the upper movable contact 15. Then, the bulging portion 1 of the upper movable contact 15
5a are arranged so as to oppose each other so as to cover the lower movable contact 14, and the peripheral portion of the upper movable contact 15 is placed in contact with the second peripheral fixed contact 12c so that each contact portion to the storage portion 11a. Storage is completed.

The cover sheet 17 is formed of a substantially rectangular resin sheet, and is used as an abutting portion of an operating portion such as a key top when the upper movable contact 15 is operated, and also the housing. 11 storage part 11a
By being attached to the upper surface of the upper movable contact 15, the upper movable contact 15 is prevented from popping out and foreign matter such as dust is prevented from entering the contact portion.

The frame 18 is formed of a plate-shaped metal plate in a substantially rectangular shape, and a large window hole portion 18a is provided in the center thereof. A pair of vertically bent side plates (not shown) is provided on the side, and the frame 18 is locked by locking the side plates to the side surface of the housing 11.
Is attached to the upper surface of the housing 11. This time,
The cover sheet 17 is exposed from the window portion 18a, and it is possible to press the upper movable contact 15 from above to reverse the operation.

When the cover sheet 17 is pressed from the window portion 18a by an operation portion such as a key top (not shown),
The upper movable contact 15 reverses and comes into contact with the lower movable contact 14 to switch the click feeling and the contact of the first stage switch, and by further pushing, the lower movable contact 14 reverses and comes into contact with the central fixed contact 12a. As a result, the click feeling of the second step and the switching of the contacts are performed, and a double-action push button switch can be obtained.

[0011]

However, in the structure of the above-mentioned conventional push button switch, the upper movable contact 15 and the lower movable contact 14 are bulging portions 15a which are conductive metal plates and can be inverted in the center. It is formed in a circular dome shape having 14a and requires a movable contact having a large outer diameter in order to increase the operation stroke of each movable contact.
There has been a problem that the housing 11a of the housing 11 for housing this has to be enlarged, and the outer shape of the housing 11 becomes large.

Therefore, according to the present invention, the above-mentioned problems are solved, the operation stroke of the movable contact is secured, and
An object of the present invention is to provide a structure of a push button switch that can reduce the size of the housing.

[0013]

In order to solve the above-mentioned problems, as a first means of the present invention, a housing having a housing portion, a central fixed contact disposed on the inner bottom surface of the housing portion of the housing, and a center thereof are provided. A peripheral fixed contact arranged outside the fixed contact, and a dome-shaped movable contact whose bulging portion center is arranged so as to face the central fixed contact and whose peripheral portion constantly contacts the peripheral fixed contact. , The movable contact has a plurality of arms extending in a cross direction in succession to the reversible bulging portion, and a diagonal square portion of the housing connected to the storage portion to be movable. It is characterized in that an accommodation recess for accommodating each arm portion of the contact point is formed so as to be bendable and extendable, and the peripheral fixed contact that is in constant contact with at least one of the arm sections is disposed in the accommodation recess.

As a second means, a housing having an accommodating portion, a central fixed contact disposed on the inner bottom surface of the accommodating portion of the housing, and a first peripheral fixed contact disposed outside the central fixed contact. A second peripheral fixed contact disposed further outside the first peripheral fixed contact, a center of the bulging portion disposed to face the central fixed contact, and a peripheral edge portion of the first peripheral fixed contact.
A dome-shaped lower movable contact that is in constant contact with the peripheral fixed contact, a larger diameter than the outer shape of the lower movable contact, the center of the bulging portion is disposed so as to cover the lower movable contact, and the peripheral portion is the A dome-shaped upper movable contact that is in constant contact with the second peripheral fixed contact, wherein the upper movable contact has a plurality of arms extending in a cross direction continuously from the reversible bulging portion; In the square portion on the diagonal line of the above, a storage recess that is connected to the storage portion and that stores each arm portion of the upper movable contact in a bendable and expandable manner is formed, and at least one arm portion is always provided in the storage recess. It is characterized in that the second peripheral fixed contact to be in contact is arranged.

As a third means, the lower movable contact has an outer diameter formed in a substantially circular dome shape, and is formed to have a smaller diameter than the extended outer diameter of the arm portion of the upper movable contact. It is characterized by

As a fourth means, the housing recess of the housing has a front wall portion facing the tip of the arm portion and side wall portions facing both side portions of the arm portion. The front wall portion and the side wall portion are formed so that the gap formed by the side portion of the arm portion and the side portion of the arm portion is narrower than the gap formed by the front wall portion and the tip portion of the arm portion. Characterize.

As a fifth means, the arm portion is formed with an inclined surface whose side portion becomes narrower from the base end portion to the tip end portion, and the side wall portion of the accommodating recess is formed into the inclined surface. It is characterized in that it is formed by a sloping inclined portion and a parallel portion that widens toward the front wall portion.

Further, as a sixth means, the peripheral fixed contact or the second peripheral fixed contact is disposed in one of the pair of accommodating concave portions on one diagonal line of the housing, and the other pair of intersecting concave portions is formed. The bottom surface of the accommodation recess is formed lower than the contact surface of the peripheral fixed contact or the second peripheral fixed contact with the arm.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a push button switch according to the present invention are shown in FIGS. 1 is a plan view of a push button switch, FIG. 2 is a longitudinal sectional view of the same, FIG. 3 is a plan view showing an engaged state of a housing and an upper movable contact, and FIG. 4 is a plan view showing a fixed state of a housing and a lower movable contact. 5 is a plan view of the housing, FIG. 6 is a plan view of the upper movable contact, FIG. 7 is a plan view of the lower movable contact, FIG. 8 is a plan view of the adhesive sheet, and FIG.
Is an operation explanatory diagram when there is no operation, FIG. 10 is an operation explanatory diagram when the first stage is on, and FIG. 11 is an operation explanatory diagram when the second stage is on.

In the figure, the housing 1 is formed of an insulating material such as a synthetic resin into a box-like shape having an accommodating portion 1a inside and a square outer shape with an open upper surface. This storage 1
a is formed of a substantially circular base portion 1b formed in a concave shape in the center of the housing 1, and a substantially rectangular accommodation recess 1c that is connected to the base portion 1b and extends to a diagonal square portion of the housing 1. Has been done. Further, the side wall portion of the accommodating recessed portion 1c is formed by an inclined portion 1d having a narrow width toward the front wall portion in a continuous portion with the base portion 1b, and a parallel portion 1e extending in parallel from the inclined portion 1d. ing. Also, the base 1
In the center of b, a groove portion 1 having a substantially circular shape is provided at a position lowered by one step.
f is formed. A lower movable contact 4, which will be described later, is accommodated in the groove portion 1f, and the base portion 1 covers the upper surface thereof.
The upper movable contact 5, which will be described later, is housed in the housing b and the housing recess 1c.

A central fixed contact 2a made of a conductive metal material is provided at the center of the inner bottom surface of the housing portion 1a of the housing 1.
The upper surface side is arranged so as to be exposed, and at a position facing each other with the central fixed contact 2a sandwiched therebetween, the first fixed contact 2a is made of a conductive metal material so as to project further from the central fixed contact 2a. Peripheral fixed contacts 2b are provided. Further, at a position outside the first peripheral fixed contact 2b, one pair of the accommodating recesses 1c on the diagonal line of the housing 1 is provided.
Is provided with a second peripheral fixed contact 2c, which is also made of a conductive metal material, in a state where it is further projected. Then, the bottom surfaces of the other pair of accommodating recesses 1c intersecting with this are formed to be lower than the contact surface of the second peripheral fixed contact 2c.

Further, on the opposing outer surfaces of the housing 1, to the circuit board such as a device which is led out from the central fixed contact 2a and the first and second peripheral fixed contacts 2b and 2c and is projected outward. Connection terminals 3a, 3b, 3c for connection are formed.

The lower movable contact 4 is formed of a conductive metal plate in a circular shape having a small diameter, and has a bulge 4 which can be inverted in the center.
It is formed in a dome shape having a. The lower surface of the top of the bulging portion 4a serves as a central contact portion that contacts the central fixed contact 2a.

The upper movable contact 5 is also formed of a conductive metal plate in the shape of a dome having a reversible bulge 5a in the center, and a plurality of arms extending continuously in the cross direction from the bulge 5a. 5b is formed and has a cross shape as a whole. In addition, the outer diameter connecting the arms 5b is formed to be larger than the outer diameter of the lower movable contact 4. The side portion of the arm portion 5b is formed with an inclined surface 5c that becomes narrower from the base end portion toward the distal end portion, and the inclined surface 5c and the inclined portion 1d of the accommodating recess 1c are not aligned with each other. It is formed as follows.

When the lower movable contact 4 is stored in the storage portion 1a, the center of the storage portion 1 is the dome-shaped bulging portion 4a.
a While facing the central fixed contact 2a arranged in the center of a, the peripheral edge of the lower movable contact 4 is placed in contact with the pair of first peripheral fixed contacts 2b. This time,
A substantially circular recessed groove portion 1f is formed along the outer peripheral portion of the lower movable contact 4 at a position lowered by one step in the storage portion 1a, and the lower movable contact 4 is accommodated in the recessed groove portion 1f to form an outer peripheral portion. Will be positionally regulated.

On the upper surface side of the lower movable contact 4, an annular adhesive sheet 6 having a through hole 6a formed in the center is attached so as to cover the upper surface side of the lower movable contact 4, and By bonding the annular portion 6b of the sheet 6 over the entire circumference of the peripheral edge portion of the lower movable contact 4 and the edge portion of the concave groove portion 1f, the lower movable contact 4 is attached to the concave groove portion 1.
It is designed to be held at f.

As described above, the recessed groove portion 1f facilitates the positioning of the lower movable contact 4 to be attached and fixed by the adhesive sheet 6, and the gap between the recessed groove portion 1f and the outer peripheral edge of the lower movable contact 4 is adhered to the adhesive sheet. Since it is covered with 6, it is possible to reduce the intrusion of dust. Further, when the adhesive sheet 6 is formed of a flexible resin sheet having an adhesive layer formed on one surface, and the dome-shaped bulging portion 4a of the lower movable contact 4 is inverted by a pressing operation. Also in the above, the annular portion 6b is adhered to the lower movable contact 4 and the storage portion 1a so as to be able to follow the reversing operation.

Further, since the top of the bulging portion 4a of the lower movable contact 4 is exposed from the through hole 6a of the adhesive sheet 6, it is possible to contact the upper movable contact 5 and The peripheral edge of the movable contact 4 is attached to the adhesive sheet 6
The peripheral portion of the lower movable contact 4 is always in contact with the first peripheral fixed contact 2b by being adhesively held in the storage portion 1a by the annular portion 6b of the lower movable contact 4
Can be used as a conduction path for switching with the upper movable contact 5.

When accommodating the upper movable contact 5 in the accommodating portion 1a, the center of the bulging portion 5a of the upper movable contact 5 is disposed so as to face the upper surface of the lower movable contact 4 so as to face each other. , The arm portion 5b of the movable contact 5 is positioned in the accommodating recess 1c of the accommodating portion 1a, and the arm portion 5b is
The peripheral edge portion of the above is placed in contact with the second peripheral fixed contact 2c. At this time, the side portion of the arm portion 5b is formed with an inclined surface 5c that becomes narrower from the base end portion toward the tip portion, and the inclined surface 5c of the arm portion 5b and the side wall portion of the accommodation recess 1c. Since the inclined portion 1d and the inclined portion 1d are formed so as to line up with each other, the upper movable contact 5 is formed by the inclined surface 5c and the inclined portion 1d.
Is regulated.

In this way, the position regulation of the upper movable contact 5
Since the inclined surface 5c on the side of the arm portion 5b and the inclined portion 1d of the side wall portion of the accommodating recess 1c for accommodating the arm portion 5b are used, the side wall portion and the arm portion 5b side And a gap G1 formed by the front wall of the accommodation recess 1c and the tip of the arm 5b.
By forming the front wall portion and the side wall portion so as to be narrower than 2, the gap G2 between the front wall portion of the accommodation recess 1c and the tip portion of the arm portion 5b can be set to be wide. When the upper movable contact 5 is pressed, the front end of the arm 5b does not collide with and is restrained from the front wall, so that the operation feeling at the time of reversal is not affected and accurate positioning is performed. Will be possible.

The side portion of the arm portion 5b is formed with an inclined surface 5c which becomes narrower from the base end portion toward the distal end portion, and the inclined surface 5c and the side wall portion of the accommodation recess 1c are inclined. Since the portion 1d and the portion 1d are formed so as to be aligned with each other, the arm portion 5b and the accommodating recess 1 due to the operation of the upper movable contact 5 are formed.
Since shaving with c can be reduced, contact failure due to the influence of shavings or the like can be prevented, and contact reliability can be improved.

Further, another pair of accommodation recesses 1c intersecting with one pair of accommodation recesses 1c on the diagonal line of the housing 1 in which the second peripheral fixed contact 2c is disposed.
Since the bottom surface of the second peripheral fixed contact 2c is formed lower than the contact surface of the second peripheral fixed contact 2c with the arm portion 5b, the second peripheral fixed contact 2c and the arm portion 5b surely contact each other and the other arm Part 5
It is possible to prevent the contact of b from coming into contact with the bottom of the accommodating recess 1c and making the contact unstable.

The lower movable contact 4 placed on the lower side of the upper movable contact 5 is formed in a dome shape with a substantially outer diameter, and has a plurality of crosses extending in the cross direction of the upper movable contact 5. Since the diameter is smaller than the outer diameter connecting the arms 5b, it can be laid out on the housing 1 without interfering with the arms 5b of the upper movable contact 5, and positioning in the rotational direction can be performed. Since it is unnecessary, it can be easily incorporated.

In this case, when the lower movable contact 4 is accommodated in the accommodating portion 1a, the peripheral portion of the lower movable contact 4 is provided on the upper surface of the first peripheral fixed contact 2b arranged in the accommodating portion 1a. Although it is placed in abutting state, since the first peripheral fixed contact 2b is formed one step higher than the central fixed contact 2a, the lower movable contact 4 on the first peripheral fixed contact 2b is Good sitting and dome-shaped bulge 4a
Since the operation stroke at the time of reversing is secured, the operation feeling becomes good.

Similarly, the second peripheral fixed contact 2c and the upper movable contact 5 are also formed so that the second peripheral fixed contact 2c is one step higher than the first peripheral fixed contact 2b. The upper movable contact 5 sits well on the peripheral fixed contact 2c, and the operation stroke for reversing the dome-shaped bulging portion 5a is secured, so that the operation feeling is also good.

A cover sheet 7 made of a substantially rectangular resin sheet is attached to the opening of the storage portion 1a so as to cover the upper surface of the upper movable contact 5. The cover sheet 7 is fixed to the upper surface of the dome-shaped swelling portion 5a of the upper movable contact 5 so that the peripheral edge of the upper movable contact 5 is brought into contact with the second peripheral fixed contact 2c, and is pressed. In this case, the sheet acts as an operation sheet, and covers the storage portion 1a and is attached to the upper surface to prevent the upper movable contact 5 from popping out and dust or the like from entering the contact portion. ing.

The frame 8 is formed of a plate-shaped metal plate in a substantially rectangular shape, and a large window hole portion 8a is provided in the center thereof. Further, a pair of vertically bent side plates (not shown) is provided on the side, and by locking the side plates to a locking portion (not shown) provided on the side surface of the housing 1, The frame 8 is attached to the upper surface of the housing 1. At this time, the cover sheet 7 is interposed between the frame 8 and the housing 1, and a part of the cover sheet 7 is exposed from the window hole portion 8a.

Next, the operation of the push button switch having the above structure will be described with reference to FIGS. As shown in FIG. 9, when the switch is in the non-pressing operation state, the peripheral portion of the upper movable contact 5 is in contact with the second peripheral fixed contact 2c, but the dome-shaped bulge portion 5a is the lower movable contact. 4 is separated from the lower movable contact 4, and the peripheral edge of the lower movable contact 4 is the first
Although in contact with the peripheral fixed contact 2b, the dome-shaped bulging portion 4a is separated from the central fixed contact 2a, and the upper and lower two stages of the switch are off.

From this state, as shown in FIG. 10, when the cover sheet 7 is pressed from the window portion 8a of the frame 8 by the operation portion such as the key top 9, it is fixed to the lower surface side of the cover sheet 7. The upper surface of the bulged portion 5a of the upper movable contact 5 thus pressed is pressed to push the bulged portion 5a downward.

At this time, the bulging portion 5a of the upper movable contact 5 is
Is pressed downward, the bulging portion 5a of the upper movable contact 5 is inverted downward. For this reason,
The lower surface of the bulging portion 5a is the bulging portion 4 of the lower movable contact 4.
a. The second peripheral fixed contact 2c and the first fixed contact 2 which are in contact with the upper surface of the second movable contact 4 and the upper and lower movable contacts 4 and 5 are conductive paths.
It is electrically connected to b, and the first stage (upper) switch is turned on.

From this state, as shown in FIG. 11, when the key top 9 is further pressed, the lower surface of the bulging portion 5a of the upper movable contact 5 causes the upper surface of the bulging portion 4a of the lower movable contact 4 to move upward. When pushed, the bulging portion 4a is pushed downward.

At this time, the bulging portion 4a of the lower movable contact 4 is
Is pressed downward, the bulging portion 4a of the lower movable contact 4 is inverted downward. For this reason,
The lower surface of the bulged portion 4a contacts the central fixed contact 2a, and the first peripheral fixed contact 2b via the lower movable contact 4.
And the central fixed contact 2a are electrically connected to each other to form a second stage (lower part).
Switch turns on.

As described above, when the cover sheet 7 is pressed by the key top 9, the upper movable contact 5 is inverted and comes into contact with the lower movable contact 4, thereby performing the click feeling of the first stage switch and switching of the contact. By further pushing, the lower movable contact 4 is inverted and comes into contact with the central fixed contact 2a, so that the click feeling of the second stage and the switching of the contact are performed, and a double-action push button switch is obtained.

When the pressing force on the key top 9 is released from this state, the bulging portions 4a, 5a of the upper and lower movable contacts 4, 5 are reversed by their own elasticity to return to the initial state. The key top 9 is pressed upward by the urging force at this time and returns to the initial position. At this time, as the bulging portions 4a, 5a of the upper and lower movable contacts 4, 5 are reversed, the bulging portions 4a, 5
The lower surface of a is separated from the upper surface of the lower movable contact 4 and the central fixed contact 2a, and the first-stage and second-stage switches are turned off.

According to the above configuration, the annular pressure-sensitive adhesive sheet 6 having the through hole 6a in the center is provided in the housing portion 1a of the housing 1 so as to cover the upper surface side of the lower movable contact 4, and the pressure-sensitive adhesive sheet is provided. 6, the bulging portion 5a of the lower movable contact 5 is exposed from the through hole 6a, and the upper movable contact 5 is arranged so as to be in contact therewith, and the annular portion 6b of the adhesive sheet 6 surrounds the lower movable contact 4. Since the portion is adhered to and held in the storage portion 1a of the housing 1 over the entire circumference, the upper movable contact 5 and the lower movable contact 4 can be arranged so as to be able to contact each other through the through hole 6a of the adhesive sheet 6. At the same time, the lower movable contact 4 can be easily attached to the housing portion 1a of the housing 1.

Further, the adhesive sheet 6 can cover the entire outer circumference between the outer peripheral portion of the lower movable contact 4 and the housing 1 so as to follow the reversing operation of the lower movable contact 4. In addition, the intrusion of dust can be reduced and the contact reliability can be improved.

Further, according to the above construction, the upper movable contact 5 is provided with the plurality of arms 5b extending in the cross direction in succession to the reversible bulging portion 5a, and on the diagonal line of the housing 1. The square portion is formed with a housing recess 1c that is connected to the housing 1a and houses each arm 5b of the upper movable contact 5 in a bendable and expandable manner, and at least one arm 5b is housed in the housing recess 1c. Since the second peripheral fixed contact 2c, which is always in contact with the above, is provided, the operation stroke of the upper movable contact 5 can be secured by the arm portion 5b, and the arm portion 5b is fixed to the square portion of the housing 1. By arranging in the above, the width of the outer shape of the rectangular housing can be reduced as compared with the case where the circular dome-shaped movable contact is used.

In the above embodiment, the structure of the push button switch having a double-action double-contact type contact portion has been described. However, the movable contact is only the upper movable contact 5, and the lower movable contact 4 is not provided. Of course, the present invention can be applied to push button switches of the type.

[0049]

As described above, the push button switch of the present invention has a housing having a housing portion, a central fixed contact disposed on the inner bottom surface of the housing portion of the housing, and a central fixed contact disposed outside the central fixed contact. And a dome-shaped movable contact whose bulging portion center is disposed so as to face the central fixed contact and whose peripheral portion is always in contact with the peripheral fixed contact. A housing that extends a plurality of arms in a cruciform direction in succession to the bulge, and a diagonal square of the housing that is connected to the housing to house each arm of the movable contact in a bendable and extendable manner. Since the concave portion is formed and the peripheral fixed contact which is in constant contact with at least one arm portion is provided in the accommodating concave portion, the operation stroke of the upper movable contact can be secured by the arm portion and the arm portion can be secured to the housing. Placed in the square Accordingly, compared with the case of using the movable contact of the shaped circular dome, it is possible to reduce the width of the outer shape of a housing of rectangular shape downsizing can be achieved.

Further, a housing having an accommodating portion, a central fixed contact disposed on the inner bottom surface of the accommodating portion of the housing, a first peripheral fixed contact disposed outside the central fixed contact, and the first peripheral portion. A second peripheral fixed contact disposed further outside the fixed contact, and a dome-shaped lower movable portion in which the center of the bulging portion is disposed so as to face the central fixed contact and the peripheral edge portion is in constant contact with the first peripheral fixed contact. The contact and the dome-shaped upper movable member having a diameter larger than the outer shape of the lower movable contact, the center of the bulging portion is disposed so as to face the lower movable contact, and the peripheral edge of the contact is always in contact with the second peripheral fixed contact. The upper movable contact has a plurality of arms extending in a cross direction in succession to the reversible bulging portion, and a diagonal square portion of the housing connected to the storage portion. A housing recess that houses each arm of the upper movable contact Since the second peripheral fixed contact, which is always in contact with at least one arm portion, is provided in the housing recess, the operation stroke of the upper movable contact can be secured by the arm portion, and the arm portion can be secured to the housing. By arranging in the square part, the width of the outer shape of the rectangular housing can be made smaller than when using a circular dome-shaped movable contact, and even in the case of a double-action type two-stage switch Can be miniaturized.

Further, the lower movable contact has an outer diameter formed in a substantially circular dome shape, and since the arm portion of the upper movable contact is formed to have a smaller diameter than the extended outer diameter, the upper movable contact is formed. It can be laid out in the housing without interfering with the arms of the above, and the positioning in the rotational direction is unnecessary, so that it can be easily incorporated.

The housing recess of the housing has a front wall portion facing the tip end portion of the arm portion and side wall portions facing both side portions of the arm portion, and is formed by the side wall portion and the side portion of the arm portion. Since the front wall portion and the side wall portion are formed so that the gap formed by the front wall portion and the tip portion of the arm portion is narrower than the gap formed by the front wall portion and the tip portion of the arm portion, Since the gap can be set wide, the tip of the arm will not hit and be restrained by the front wall when pressing the upper movable contact, which may affect the operation feeling during reversal. Therefore, the positioning can be performed accurately.

Further, the arm portion is formed with an inclined surface whose side portion becomes narrower from the base end portion toward the tip end portion, and faces the inclined wall portion and the front wall portion which follow the side wall portion of the accommodating concave portion as the inclined surface. Since it is formed by the parallel portion that spreads out, the abrasion of the arm portion and the accommodating recess due to the operation of the upper movable contact can be reduced, so contact failure due to the influence of shavings and the like can be prevented, and contact reliability can be improved.

Further, the peripheral fixed contact or the second peripheral fixed contact is arranged in one pair of accommodation recesses on the diagonal line of the housing, and the bottom surfaces of the other pair of accommodation recesses intersecting this are arranged.
Since the peripheral fixed contact or the second peripheral fixed contact is formed lower than the contact surface with the arm portion, the second peripheral fixed contact and the arm portion are surely brought into contact with each other, and the other arm portion contacts the bottom surface of the accommodating recess. It is possible to avoid contact from becoming unstable.

[Brief description of drawings]

FIG. 1 is a plan view showing a push button switch according to an embodiment of the present invention.

FIG. 2 is a vertical sectional view showing the same push button switch of the present invention.

FIG. 3 is a plan view showing an engaged state of the housing and the upper movable contact of the present invention.

FIG. 4 is a plan view showing a fixed state of a housing and a lower movable contact of the present invention.

FIG. 5 is a plan view showing a housing of the present invention.

FIG. 6 is a plan view showing an upper movable contact of the present invention.

FIG. 7 is a plan view showing a lower movable contact of the present invention.

FIG. 8 is a plan view showing an adhesive sheet of the present invention.

FIG. 9 is an operation explanatory view showing a state when the push button switch of the present invention is not operated.

FIG. 10 is an operation explanatory view showing a state when the first stage of the push button switch of the present invention is turned on.

FIG. 11 is an operation explanatory view showing a state of the push button switch of the present invention when the second stage is on.

FIG. 12 is a plan view showing a conventional push button switch.

FIG. 13 is a vertical sectional view showing a conventional push button switch.

[Explanation of symbols]

1 housing 1a Storage section 1b base 1c storage recess 1d slope 1e Parallel part 1f concave groove 2a Central fixed contact 2b 1st peripheral fixed contact 2c Second peripheral fixed contact 3a, 3b, 3c connection terminals 4 Lower movable contact 4a bulge 5 Upper movable contact 5a bulge 5b arm 5c slope 6 Adhesive sheet 6a through hole 6b Ring part 7 cover sheet 8 frames 8a window hole 9 key tops G1, G2 void

Claims (6)

[Claims] 1. A housing having an accommodating portion, a central fixed contact disposed on the inner bottom surface of the accommodating portion of the housing, a peripheral fixed contact disposed outside the central fixed contact, and a bulging portion centered at the center. A dome-shaped movable contact which is disposed so as to face the central fixed contact and whose peripheral portion is in constant contact with the peripheral fixed contact. A plurality of arm portions are extended, and a housing concave portion that is connected to the housing portion and houses each arm portion of the movable contact so as to be bendable and extendable is formed in a diagonal square portion of the housing. A push button switch, characterized in that the peripheral fixed contact, which is in constant contact with at least one of the arm portions, is provided in the recess. 2. A housing having an accommodating portion, a central fixed contact disposed on the inner bottom surface of the accommodating portion of the housing, a first peripheral fixed contact disposed outside the central fixed contact, and the first periphery. A second one disposed outside the fixed contact
A peripheral fixed contact, a dome-shaped lower movable contact whose central part of the bulging portion is disposed so as to face the central fixed contact, and whose peripheral edge is in constant contact with the first peripheral fixed contact, and an outer shape of the lower movable contact. And a dome-shaped upper movable contact whose peripheral portion is in constant contact with the second peripheral fixed contact and which has a large diameter and whose center of the bulging portion is opposed to cover the lower movable contact. The contact has a plurality of arms extending in a cross direction continuously from the reversible bulging portion, and a diagonal square portion of the housing is connected to the accommodating portion and is connected to the upper movable contact. A push button switch, characterized in that an accommodation recess for accommodating each of the arms is formed, and the second peripheral fixed contact that is in constant contact with at least one of the arms is disposed in the accommodation recess. 3. The lower movable contact has an outer diameter formed into a substantially circular dome shape, and is formed to have a smaller diameter than the outer diameter of the extended arm portion of the upper movable contact. The push button switch according to claim 2. 4. The housing recess of the housing has a front wall portion facing the tip end portion of the arm portion and side wall portions facing both side portions of the arm portion, and the side wall portion and the arm portion side. The front wall portion, so that the gap formed by the portion is narrower than the gap formed by the front wall portion and the tip portion of the arm portion,
The push button switch according to claim 1 or 2, wherein a side wall portion is formed. 5. The arm portion is formed with an inclined surface in which the side portion becomes narrower from the base end portion toward the distal end portion, and the side wall portion of the accommodating recessed portion follows the inclined surface and the front portion. 5. A parallel portion that widens toward the wall portion is formed.
Push button switch described. 6. The peripheral fixed contact or the second peripheral fixed contact is disposed in one pair of the accommodation recesses on one diagonal line of the housing, and the bottom surface of the other pair of accommodation recesses intersecting the accommodation recesses is formed. The push button switch according to claim 1, wherein the peripheral fixed contact or the second peripheral fixed contact is formed lower than a contact surface with the arm portion.