JP2004273331A - Push-button switch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a push-button switch with high contact reliability which provides a desired operation feeling, prevents the invasion of dusts and the like to stabilize the contact state between a movable contact and a fixed contact when a rubber spring is pushed to perform reverse operation. <P>SOLUTION: The push-button switch is provided with a housing 1 having a housing part 1a, fixed contacts 2, 3 fixed in the housing part 1a, a movable contact 4 arranged opposed to the fixed contacts 2, 3, and a rubber spring 5 having a lower end peripheral edge part 5c in the holding part 1a, a bendable skirt part 5a provided in a space formed together with an upper end pressing surface part 5b, and contacts/disconnects the movable contact 4 to/from the fixed contact 3 due to the bending of this skirt part 5a. The lower end peripheral edge part 5c of the rubber spring 5 and opposed faces of a housing wall part 1c of the housing 1 having this lower end peripheral edge part 5c held therein are formed of inclined faces or arc faces each opening from the under face side toward the top face side. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a structure of a push button switch used as an operation switch of various electronic devices, and more particularly to a structure of a push button switch using a rubber spring as a reversing spring.
[0002]
[Prior art]
As a structure of a conventional push button switch, a movable contact facing a fixed contact and a rubber spring pressing the movable contact toward the fixed contact are arranged in a housing portion of a housing to which the fixed contact is fixed. 2. Description of the Related Art A push-button switch for returning an operating stem with a resilient force is known (for example, see Patent Document 1).
[0003]
Hereinafter, the structure of a conventional push button switch will be described with reference to the drawings.
FIG. 11 is a plan view of a conventional push button switch, and FIG. 12 is a sectional view of the conventional push button switch.
[0004]
In the figure, a housing 31 is formed of an insulating material such as a synthetic resin in a box shape having an open upper surface. The housing 31 is provided with a storage portion 31a having a storage wall portion 31b on the lower surface side, and a pair of fixed terminals 32 formed by bending a conductive material such as a metal plate on the inner bottom of the storage portion 31a. , 33 are buried. One end of the pair of fixed terminals 32 and 33 is exposed from the inner bottom surface of the housing 31 to form contact portions 32a and 33a, respectively, and the other end is led out of the housing 31 and is connected to the terminal portion. 32b and 33b are formed.
[0005]
The movable contact 34 is formed of a conductive thin metal plate having a spring property, and has an annular crosspiece 34a and a contact piece 34b integrally cut and raised at the center thereof. The movable contact 34 is disposed such that the crosspiece 34a is placed on the contact 33a of the fixed terminal 33 in a conductive state, and the contact piece 34b is opposed to the contact 32a of the fixed terminal 32 in a separated state. Have been.
[0006]
The rubber spring 35 is formed of a flexible elastomer or silicone rubber or the like, and has a dome shape having an outer shape of an open bottom surface. The skirt portion 35a is bent at the time of pressing and returning to provide elasticity. The skirt portion 35a includes a pressing surface portion 35b formed at an upper portion and an outer peripheral edge portion 35c formed at a lower portion. The outer peripheral edge 35c is inserted and held in a housing wall 31b provided in the housing 31a of the housing 31.
[0007]
An operating projection 35d is formed on the lower surface side of the pressing surface 35b, and the tip of the operating projection 35d presses the contact piece 34b of the movable contact 34 to conduct with the contact 32a of the fixed terminal 32. It is made to let.
[0008]
The stem 36 is formed of an insulating material such as a synthetic resin, is inserted into the opening of the housing 31, and the pressing projection 36 a of the stem 36 is brought into contact with the pressing surface 35 b of the rubber spring 35 to The rubber spring 35 is pressed downward. After the stem 36 is pressed, the stem 36 is returned to the initial position by the elastic force when the skirt portion 35a of the rubber spring 35 is bent and returned.
[0009]
[Patent Document 1]
JP 2000-260256 A
[0010]
[Problems to be solved by the invention]
However, in the structure of the conventional push button switch described above, the housing wall 31b for housing the rubber spring 35 provided in the housing 31a of the housing 31 and the outer peripheral edge 35c of the rubber spring 35 are provided. In consideration of the ease of assembling the rubber spring 35, the inner diameter of the housing wall 31b is made larger than the outer peripheral edge 35c of the rubber spring 35 to form the gap G.
[0011]
For this reason, the rubber spring 35 is displaced within the housing wall portion 31b, so that the rubber spring 35 is end-pushed and affects the operation feeling, and dust enters the contact portion from the gap G, resulting in poor contact. There was a fear. In addition, since the outer peripheral edge 35c of the rubber spring 35 expands when pressed in the gap G and the amount of movement until the outer peripheral edge 35c abuts on the housing wall 31b is added, the peak position of the operating force (the point at which the rubber spring 35c is bent and inverted). Is shifted rearward (on the contact ON position side), so that the stroke after reversal becomes short, and there is a problem that a good operation feeling cannot be obtained.
[0012]
Therefore, the present invention solves the above-described problems, and when the rubber spring is pressed to perform the reversing operation, a desired operation feeling is obtained, and at the same time, the intrusion of dust and the like is prevented, so that the movable contact and the fixed contact can be prevented. An object of the present invention is to provide a pushbutton switch that stabilizes a contact state and has high contact reliability.
[0013]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, in the present invention, as a first means, a housing having a storage part, a fixed contact fixed in the storage part, a movable contact arranged opposite to the fixed contact, A rubber spring for holding a lower end outer peripheral edge portion in the storage portion, a bendable skirt portion between the upper end pressing surface portion and the upper end pressing surface portion, and bringing the movable contact into and out of contact with the fixed contact by bending the skirt portion, Opposite surfaces of the lower end outer peripheral edge of the rubber spring and the housing wall portion of the housing where the lower end outer peripheral edge is held are formed by inclined surfaces or arcuate surfaces that expand from the lower surface toward the upper surface. It is characterized by.
[0014]
Further, as a second means, the height of the housing wall portion of the housing is formed to be the same as or higher than the height of the upper surface side of the lower peripheral edge of the rubber spring. Features.
[0015]
As a third means, the expansion angle of the outer peripheral edge of the lower end of the rubber spring is formed to be larger than the expansion angle of the housing wall of the housing, and The rubber spring is formed so that the dimensional difference on the lower surface side is larger than the dimensional difference on the upper surface side from the outer peripheral edge of the lower end of the rubber spring.
[0016]
Further, as a fourth means, the lower end outer peripheral edge of the rubber spring is connected to an opposing surface of a housing wall portion of the housing where the lower end outer peripheral portion is held, and communicates with the inner surface side of the rubber spring. The air flow path is formed.
[0017]
As a fifth means, a stem is held in the housing portion of the housing so as to be able to move up and down and presses an upper end pressing surface portion of the rubber spring, and the inner wall portion of the housing portion guides the stem up and down. A guide groove is formed, and the air flow path is formed by the guide groove.
[0018]
As a sixth means, the guide groove extends to the bottom surface side of the housing, and the inner bottom of the guide groove is formed at a position one step lower than the contact surface of the fixed contact. .
[0019]
Further, as a seventh means, the movable contact is formed of a metal plate having a spring property, and is sandwiched between a lower surface side of a lower peripheral edge of a lower end of the rubber spring and an upper surface side of the fixed contact. A protrusion is formed on a contact surface between the rubber spring and the fixed contact, and the protrusion connects the inner surface of the rubber spring to the guide groove.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, one embodiment of the push button switch of the present invention is shown in FIGS. 1 is a plan view of a push button switch, FIG. 2 is a sectional view taken along line 2-2 of FIG. 1, FIG. 3 is a sectional view taken along line 3-3 of FIG. 1, FIG. 4 is a plan view of a housing, and FIG. 6, FIG. 6 is a cross-sectional view of a rubber spring, FIG. 7 is a plan view of a movable contact, FIG. 8 is a cross-sectional view of a movable contact, and FIG. 9 is an explanatory diagram showing an operating force characteristic of the rubber spring.
[0021]
The housing 1 is formed in a rectangular box shape whose upper surface is opened with an insulating material such as a synthetic resin. A housing 1a is formed in the opening of the housing 1, and a pair of fixed contacts 2 and 3 made of a conductive metal material such as brass are inserted into the inner bottom of the housing 1a. The housing 1 is formed integrally with the housing 1 by a method such as molding.
[0022]
A guide groove 1b is provided on the inner wall of the housing 1a of the housing 1 so that a guide protrusion 6c of a stem 6 described later is engaged with the diagonal square. By providing the guide groove 1b, it is possible to guide the stem 6 into the housing 1 and regulate the position thereof when the stem 6 moves up and down, which will be described later.
[0023]
Further, a housing wall portion 1c formed of an inclined surface that expands from the lower surface side to the upper surface side is formed on the inner wall portion on the lower surface side of the housing portion 1a. An outer peripheral edge 5c of a lower end of a rubber spring 5 described later is opposed to and held by the housing wall 1c. Further, a part of the housing wall 1c and a part of the guide groove 1b are formed so as to be connected to each other, and the inside of the housing 1a surrounded by the housing wall 1c is formed. The inner bottom surface of the guide groove 1b is formed at a position one step lower than the inner bottom surface.
[0024]
A part of the housing wall part 1c of the housing 1 and a part of the guide groove part 1b are formed so as to be connected to each other, and the connected part is an air communicating with a space on the inner surface side of the rubber spring 5 described later. A flow path is configured.
[0025]
As described above, by forming the guide groove 1b in connection with a part of the housing wall portion 1c of the housing 1, an air flow path communicating with the inner surface side of the rubber spring 5 described later is formed. Therefore, when the rubber spring 5 is pressed and the reversing operation is performed, even if the housing wall portion 1c of the housing 1 and the outer peripheral edge portion 1c of the lower end of the rubber spring 5 are held in close contact with each other, the air inside the rubber spring 5 is held. Can be released to the outside, so that the rubber spring 5 can be reliably inverted and returned.
[0026]
Further, since the air flow path can be shared by the guide groove 1b, there is no need to newly provide an air flow path, and the configuration is simplified.
[0027]
A pair of fixed contacts 2 and 3 are buried in the inner bottom of the housing 1, a plurality of bent portions are formed in the middle of the buried portion, and one end of the bent portion extends outside the housing 1. Thus, the terminal portions 2a and 3a are formed. In addition, the other end side is exposed on the inner bottom surface inside of the housing portion 1a of the housing 1 surrounded by the housing wall portion 1c, and a pair of oppositely arranged ones are provided while maintaining a certain gap. The contact portions 2b and 3b are formed.
[0028]
In this case, the guide groove 1b is formed so as to extend to the bottom surface side of the housing 1, and the inner bottom of the guide groove 1b is set to be lower than the surfaces of the contact portions 2b, 3b of the fixed contacts 2, 3. Since it is formed at a lower position, even if dust enters the storage portion 1a, the entered dust is accumulated at the inner bottom of the guide groove portion 1b. This makes it possible to suppress the intrusion of dust and improve the reliability of contact.
[0029]
The movable contact 4 is formed of a phosphor bronze plate or a stainless steel plate having a spring property, has a substantially circular outer shape, and has a ring-shaped bar portion 4a formed outside thereof. An arc-shaped hole 4b is provided inside the bar 4a, and one end of the hole 4b is connected to the bar 4a by a connecting portion 4c at the center, and the other end is integrally cut and raised. The formed contact piece 4d is formed. The contact piece 4d is provided so as to be swingable on the crosspiece 4a via the connection portion 4c, and the tip end side is bent at an angle so as to be inclined slightly upward. Has become.
[0030]
The contact piece 4d has a contact protrusion 4e that contacts the rubber spring 5 on a surface facing the rubber spring 5 described later, that is, on an upper surface that is cut and raised and inclined and bent. Is formed. By providing the projection 4e, almost the center of the contact piece 4d is pressed, so that the contact is stable. Further, a plurality of protrusions 4f that are in contact with the contact portion 2b of the fixed contact 2 are formed on the lower surface, so that stable contact can be obtained.
[0031]
A projection 4g protruding toward the fixed contact 3 is formed on the lower surface of the crosspiece 4a. By providing the projection 4g, when the movable contact 4 is placed between the lower surface of a rubber spring 5 described later and the fixed contact 3 and is mounted on the fixed contact 3, the contact 3b and the projection are formed. The gap H (see FIG. 3) is ensured without the portion 4g being in contact with the periphery of the portion 4g. Thus, the movable contact 4 is always in contact with the fixed contact 3 and is formed so as to be able to contact and separate from the fixed contact 2 to constitute a switch contact.
[0032]
Since the movable contact 4 is provided with the protrusion 4g as described above, the space on the inner surface side of the rubber spring 5 and the guide groove 1b of the housing 1 can communicate with each other. Since the air in the rubber spring 5 is surely guided to the guide groove 1b from the gap H between the movable contact 4 and the fixed contact 3, the inversion and the return of the rubber spring 5 are surely performed. Can be done.
[0033]
In the present embodiment, the projection 4g is formed on the lower surface side of the crosspiece 4a of the movable contact 4, but instead of this projection 4g, a projection is formed on the upper surface side of the fixed contact 3. You may do it. Instead of the projection, a concave groove communicating with the space on the inner surface side of the rubber spring 5 may be provided on the lower surface of the rubber spring 5.
[0034]
The crosspiece 4a of the movable contact 4 is provided with a pair of projecting pieces 4h projecting outward, and when the movable contact 4 is inserted into the housing portion 1a of the housing 1, the guide groove portion is provided. The position is regulated by engaging with 1b.
[0035]
The rubber spring 5 is formed of a flexible elastomer or silicone rubber, and has a dome shape having an open bottom surface. The rubber spring 5 is bent at the time of movement and return of a stem, which will be described later, to give elasticity. It comprises a skirt 5a, a pressing surface 5b formed at the upper end of the skirt 5a, and an outer peripheral edge 5c formed at the lower end of the skirt 5a. An operation protrusion 5d is formed on the lower surface side of the pressing surface portion 5b, and the tip of the operation protrusion 5d comes into contact with the protrusion 4e provided on the upper surface side of the contact piece 4d of the movable contact 4. It has become.
[0036]
The outer peripheral surface of the outer peripheral edge 5c is formed as an inclined surface that expands from the lower surface to the upper surface. When the rubber spring 5 is inserted into the housing portion 1a of the housing 1, the outer peripheral edge portion 5c is disposed so as to face the inclined surface of the housing wall portion 1c.
[0037]
As described above, the distal end side of the lower peripheral edge portion 5c of the rubber spring 5 is formed to have a tapered shape in the mounting direction into the housing 1, so that the assembling property at the time of insertion is improved. At the same time, it is possible to reduce the gap between the housing 1 and the housing wall 1c after the insertion.
[0038]
In this case, the height of the storage wall 1c of the housing 1 is equal to or slightly higher than the height of the outer peripheral edge 5c of the rubber spring 5 on the upper surface side. It is formed as follows. By doing so, when the rubber spring 5 is pressed to perform the reversing operation, the upper surface side of the lower peripheral edge 5c of the rubber spring 5 that has been compressed and expanded does not protrude from the housing wall 1c. Therefore, it is possible to prevent the rubber spring 5 from rising from the storage wall 1c when pressed.
[0039]
Further, the mutual relationship of the inclined surfaces on which the storage wall portion 1c of the housing 1 and the outer peripheral edge portion 5c of the rubber spring 5 are arranged to face each other depends on the angle of expansion of the storage wall portion 1c of the housing 1. On the other hand, the outer peripheral edge 5c of the rubber spring 5 is formed so that the opening angle of the outer peripheral edge 5c is larger, and the upper surfaces of the housing wall 1c of the housing 1 and the outer peripheral edge 5c of the rubber spring 5 are respectively formed. The dimensional difference on the lower surface side is larger than the dimensional difference on the lower side.
[0040]
By doing so, when the rubber spring 5 is inserted into the housing wall portion 1c, the rubber spring 5 can be easily assembled, and the rubber spring 5 is housed at an appropriate position in the housing wall portion 1c. Variations in the mounting position (height dimension) of the spring 5 can be reduced. Then, the cross section 4a of the movable contact 4 can be reliably pressed toward the fixed contact 3 on the lower surface side of the rubber spring 5.
[0041]
In this embodiment, the movable contact 4 is formed of a metal plate having a spring property, and is formed so as to be sandwiched between the fixed contact 3 and the rubber spring 5. However, it is already known. Alternatively, a carbon ink contact or the like may be integrally formed on the lower end surface of the operation protrusion 5d of the rubber spring 5. In this case, the movable contact 4 becomes unnecessary, and the number of parts is reduced.
[0042]
The stem 6 is formed in a substantially circular shape with a molding material such as a synthetic resin, and has a flat pressing portion 6a which is operated by a human finger or the like on an upper surface thereof. On the lower surface side facing the pressing portion 6a, a pressing projection 6b protruding to the lower surface side, which comes into contact with the upper surface of the pressing surface portion 5b of the rubber spring 5 to bend the rubber spring 5 toward the movable contact 4 side. Is formed.
[0043]
Four guide projections 6c projecting in the cross direction are formed on the lower surface of the side surface of the stem 6. When the stem 6 is inserted into the opening of the housing 1a of the housing 1, the guide projection 6c is engaged with the guide groove 1b formed on the inner wall of the housing 1a. Thereby, the position is regulated to the housing 1 and the housing 1 is mounted so as to be movable up and down.
[0044]
Next, the operation of the push button switch having the above configuration will be described.
First, when the pressing portion 6a of the stem 6 is pressed by a person's finger or the like, the pressing protrusion 6b presses the pressing surface portion 5b of the rubber spring 5, and the skirt portion 5a is bent, thereby causing the operating protrusion 5d. Moves downward.
[0045]
Then, as shown by the solid line in FIG. 9, when the predetermined stroke is moved and the load of the operating force reaches the peak position, the skirt portion 5a is inverted and the operating protrusion 5d moves by itself and moves downward. Will be. When the operating protrusion 5d contacts the protrusion 4e on the upper surface of the contact piece 4d of the movable contact 4, the protrusion 4f on the lower surface of the contact piece 4d of the movable contact 4 makes contact with the fixed contact 2. The connection is made conductive and the contact is turned on.
[0046]
When the pressure on the stem 6 is released from this state, the stem 6 is urged upward by the elastic force of the skirt portion 5a of the rubber spring 5, and returns to the initial position. At this time, the contact piece 4d of the movable contact 4 also returns upward due to its own spring property, and the contact is turned off.
[0047]
In this case, the opposing surfaces of the lower peripheral edge 5c of the rubber spring 5 and the housing wall 1c of the housing 1 on which the lower peripheral edge 5c is held expand from the lower surface side to the upper surface side. The rubber spring 5 is formed such that the distal end side of the lower peripheral edge 5c of the rubber spring 5 has a tapered shape with respect to the mounting direction into the housing 1.
[0048]
Therefore, the gap between the outer peripheral edge 5c of the lower end of the rubber spring 5 and the housing wall 1c of the housing 1 can be reduced at the time of assembling, and when the rubber spring 5 is pressed to perform the reversing operation, the rubber Since it is possible to eliminate a gap (a play amount) until the outer peripheral edge portion 5c of the spring 5 expands and comes into contact with the housing wall portion 1c of the housing 1, as shown by a solid line in FIG. A certain point P (the point at which the skirt portion 5a is bent and inverted) can be set at an appropriate position and farther than the point R, which is the ON position of the contact point, and the stroke until the on after the inversion becomes longer. A good operation feeling at the time of operation can be obtained.
[0049]
At this time, if there is a certain gap G between the outer peripheral edge 5c of the lower end of the rubber spring 5 and the housing wall 1c of the housing 1 at the time of assembly, when the rubber spring 5 is pressed in the gap G, Since the lower end outer peripheral edge portion 5c expands and the amount of movement until the lower end outer peripheral edge portion 5c comes into contact with the housing wall portion 1c is added, as shown by a broken line in FIG. Point) is shifted backward (on the side of the ON position R of the contact), so that the stroke until the ON after the reversal is shortened, and a good operation feeling during operation cannot be obtained.
[0050]
FIG. 10 is a sectional view showing the structure of a push-button switch according to a second embodiment of the present invention. In this case, the difference from the first embodiment is that the configuration of the housing wall 1c of the housing 1 and the outer peripheral edge 5c of the lower end of the rubber spring 5 are slightly different.
[0051]
The configuration of the push button switch according to the second embodiment of the present invention is such that the lower end outer peripheral edge portion 5c of the rubber spring 5 and the facing surface of the housing wall portion 1c of the housing 1 where the lower end outer peripheral edge portion 5c is held. Each has a configuration formed by an arc surface that expands from the lower surface to the upper surface.
[0052]
Also in this case, the opposing surfaces of the lower peripheral edge 5c of the rubber spring 5 and the housing wall 1c of the housing 1 where the lower peripheral edge 5c is held expand from the lower surface side to the upper surface side, respectively. The rubber spring 5 is formed so as to have an open circular arc surface, and the distal end side of the lower peripheral edge 5c of the rubber spring 5 has a tapered shape with respect to the mounting direction into the housing 1.
[0053]
Therefore, similarly to the first embodiment, the gap between the lower peripheral edge 5c of the rubber spring 5 and the housing wall portion 1c of the housing 1 can be reduced when the rubber spring 5 is assembled. When the inversion operation is performed by pressing, the gap (play amount) until the outer peripheral edge portion 5c of the rubber spring 5 expands and comes into contact with the housing wall portion 1c of the housing 1 can be eliminated. As described above, the point P (the point where the skirt portion 5a is bent and reversed), which is the peak position of the operating force, can be set at an appropriate position and farther than the ON position of the contact, and the stroke until the ON position after the reversal Becomes longer, so that a good operation feeling at the time of operation can be obtained.
[0054]
In the embodiment of the present invention, the air flow path for allowing the space on the inner surface side of the rubber spring 5 to escape to the outside is formed by the guide groove 1b of the housing 1. A hole or groove for distribution may be formed in a part of.
[0055]
【The invention's effect】
As described above, the push button switch according to the present invention includes a housing having a storage portion, a fixed contact fixed in the storage portion, a movable contact disposed opposite to the fixed contact, and a lower end in the storage portion. A rubber spring for holding a peripheral edge portion and bendable between the upper end pressing surface portion and the upper end pressing surface portion; and a rubber spring for bringing the movable contact into and out of contact with the fixed contact by bending the skirt portion. And the opposite surface of the housing wall portion of the housing where the lower end outer peripheral portion is held is formed by an inclined surface or an arc surface that expands from the lower surface side to the upper surface side, so that it can be installed in the housing in the mounting direction. On the other hand, the tip end of the outer peripheral edge of the lower end of the rubber spring is formed to have a tapered shape, so that the assemblability is improved and the gap between the housing spring and the housing wall is reduced. Therefore, when performing the reversing operation by pressing the rubber spring, the peak position of the operating force (the point at which the rubber spring is flexed and reversed) can be set farther than the ON position of the contact point. Since the stroke until turning on is long, a good operation feeling can be obtained.
[0056]
In addition, the height of the housing wall portion of the housing is equal to or higher than the height of the upper peripheral side of the lower peripheral edge of the rubber spring, so that the rubber spring is pressed and inverted. When the operation is performed, the upper surface of the outer peripheral edge of the lower end of the rubber spring that has been compressed and expanded does not protrude from the housing wall portion, so that the rubber spring can be prevented from floating.
[0057]
Further, the expansion angle of the lower end outer peripheral edge of the rubber spring is formed to be larger than the expansion angle of the housing wall portion of the housing. Since the dimensional difference on the lower surface side is larger than the dimensional difference on the upper surface side, the rubber spring can be easily assembled and is housed at an appropriate position in the housing wall. (A height dimension) can be reduced, and the cross section of the movable contact can be reliably pressed toward the fixed contact.
[0058]
Also, since the lower peripheral edge of the rubber spring and the opposite surface of the housing wall portion of the housing where the lower peripheral edge is held, an air flow path communicating with the inner surface side of the rubber spring is formed. When the rubber spring is pressed to perform the reversing operation, the air in the rubber spring can be released to the outside even if the housing wall of the housing and the outer peripheral edge of the lower end of the rubber spring are in close contact with each other. , The return can be reliably performed.
[0059]
Further, a stem is held in the housing portion of the housing so as to be able to move up and down and presses an upper end pressing surface portion of the rubber spring. A guide groove portion is formed on the inner wall portion of the housing portion to guide the stem up and down. Since the air flow path is formed by using the air flow path, the air flow path can be used also as the guide groove, so that it is not necessary to newly provide an air flow path, and the configuration is simplified.
[0060]
In addition, the guide groove extends to the bottom side of the housing, and the inner bottom of the guide groove is formed at a position one step lower than the contact surface of the fixed contact, so that invading dust is accumulated on the inner bottom of the guide groove. Therefore, intrusion of dust into the contact portion can be suppressed, and contact reliability can be improved.
[0061]
The movable contact is formed of a metal plate having a spring property, and is sandwiched between the lower surface of the lower peripheral edge of the rubber spring and the upper surface of the fixed contact. A protrusion is formed, and the inner surface side of the rubber spring communicates with the guide groove by the protrusion, so that the air in the rubber spring is reliably discharged from the gap between the movable contact and the fixed contact formed by the protrusion. Since the rubber spring is guided to the guide groove, the rubber spring can be reliably inverted and returned.
[Brief description of the drawings]
FIG. 1 is a plan view showing a push-button switch according to a first embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1 of the present invention.
FIG. 3 is a sectional view of the present invention taken along line 3-3 in FIG. 1;
FIG. 4 is a plan view showing a housing according to an embodiment of the present invention.
FIG. 5 is a plan view showing a rubber spring according to one embodiment of the present invention.
FIG. 6 is a sectional view showing a rubber spring according to one embodiment of the present invention.
FIG. 7 is a plan view showing a movable contact according to an embodiment of the present invention.
FIG. 8 is a sectional view showing a movable contact according to an embodiment of the present invention.
FIG. 9 is an explanatory diagram showing the operating force characteristics of the rubber spring of the present invention.
FIG. 10 is a sectional view showing a push-button switch according to a second embodiment of the present invention.
FIG. 11 is a plan view showing a conventional push button switch.
FIG. 12 is a sectional view showing a conventional push button switch.
[Explanation of symbols]
1 Housing
1a Storage section
1b Guide groove
1c Storage wall
2 Fixed contacts
2a Terminal
2b Contact part
3 Fixed contacts
3a Terminal
3b Contact part
4 Moving contacts
4a pier
4b hole
4c connection
4d contact piece
4e, 4f protrusion
4g protrusion
4h protruding part
5 Rubber spring
5a Skirt
5b Pressing surface
5c Outer edge
5d working projection
6 stem
6a Pressing part
6b Pressing projection
6c Guide protrusion
G, H gap

Claims (7)

A housing having a storage portion, a fixed contact fixed in the storage portion, a movable contact disposed to face the fixed contact, and a lower end outer peripheral portion held in the storage portion and an upper end pressing surface portion. A rubber spring that has a bendable skirt portion between the movable contact and the fixed contact by bending the skirt portion, and a lower peripheral edge of the lower end of the rubber spring, and a lower peripheral edge of the lower end. A push button switch, wherein opposing surfaces of the housing wall portion of the housing to be held are formed by inclined surfaces or arc surfaces that expand from a lower surface to an upper surface. 2. The height of the housing wall of the housing is equal to or higher than the height of the outer peripheral edge of the lower end of the rubber spring on the upper surface side. Push button switch. The expansion angle of the lower peripheral edge of the rubber spring is larger than the expansion angle of the housing wall of the housing, and the housing wall of the housing and the lower peripheral edge of the rubber spring are formed. 3. The push-button switch according to claim 1, wherein the dimensional difference on the lower surface side is larger than the dimensional difference on the upper surface side. The lower end outer peripheral edge of the rubber spring and the opposing surface of the housing wall portion of the housing where the lower end outer peripheral portion is held, forming an air flow passage communicating with the inner surface side of the rubber spring. The push button switch according to any one of claims 1 to 3, wherein: A guide is provided in the housing portion of the housing so as to be able to move up and down, and a stem that presses an upper end pressing surface portion of the rubber spring is formed. 5. The push button switch according to claim 4, wherein said air flow path is formed by a guide groove. The push button switch according to claim 5, wherein the guide groove extends to a bottom surface side of the housing, and an inner bottom of the guide groove is formed at a position one step lower than a contact surface of the fixed contact. The movable contact is formed of a metal plate having a spring property, and is sandwiched between a lower surface of an outer peripheral edge of a lower end of the rubber spring and an upper surface of the fixed contact, and a contact between the movable contact and the fixed contact. 6. The push button switch according to claim 5, wherein a protrusion is formed on the surface, and the protrusion connects the inner surface of the rubber spring to the guide groove.

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