JP2003168343A - Push button switch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure of a push button switch reducing the number of components, facilitating assembly, and preventing the wear of a moving contact to enhance contact reliability. <P>SOLUTION: This push button switch is equipped with a stem 5 pushing the moving contact 4 installed so as to be capable of moving up and down in a housing part 1a of a housing 1 to fixed contacts 2a, 2b, and a cover 6 fit to the top surface of the housing 1 so as to cover the housing part 1a, and a long operation lever 6b is integrally formed at one end of the cover 5 by extending and folding back a part of the cover 6 on the top surface side of the stem 5, a stem pushing part 6c for pushing the stem 5 by coming in contact with the top surface of a pushing projection part 5a of the stem 5 and an elastically deformable elastic arm 6d extending from the stem pushing part 6c are formed in the operation lever 6b. <P>COPYRIGHT: (C)2003,JPO

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 movable contact is brought into contact with and separated from a fixed contact by being pressed, and in particular, it is used for an information input device such as a mouse and the like and requires an overstroke. And a structure of a push button switch.

[0002]

2. Description of the Related Art The structure of a conventional push button switch is shown in FIGS. FIG. 5 is a vertical sectional view of the push button switch, and FIG. 6 is a partial sectional view showing the relationship between the movable contact and the coil spring.

The conventional push button switch has a housing 21 having a housing, a central fixed contact 22a and a peripheral fixed contact 22b arranged in the housing of the housing 21, and a central fixed contact 22a and a peripheral fixed contact 22b. , A coil spring 25 disposed on the movable contact 24, and a stem 26 for pressing and reversing the movable contact 24 via the coil spring 25.
A cover 27 attached to the upper surface of the housing 21 and a dustproof sheet 28 interposed between the cover 27 and the housing 21.

The housing 21 is made of an insulating material such as synthetic resin and is formed in a box shape having an upper surface opening, and has a storage portion 21a therein. In the center of this storage part 21a,
A central fixed contact 22a made of a conductive metal material is provided so as to be exposed on the inner bottom surface, and peripheral fixed contacts made of a conductive metal material are also provided at positions facing each other across the central fixed contact 22a. 22b is provided. Further, the peripheral portion of the movable contact 24 and the peripheral fixed contact 22b are in a conductive state.

Further, the housing 21 is provided with a pair of fixed terminals 23a and 23b protruding outward from the side wall. The fixed terminals 23a and 23b are embedded in the housing 21 and are not shown. However, the central fixed contact 22a and the peripheral fixed contact 22b are electrically connected to each other. In addition, a pair of the fixed terminals 23
A and 23b are bent downward along the side wall of the housing 21 to form a soldering terminal.

When the stem 26 is pressed, the movable contact 24 is pressed and inverted through the coil spring 25 to contact the central fixed contact 22a, and the central fixed contact 22a and the peripheral fixed contact 22b are moved. The pair of fixed terminals 23a and 23b are electrically connected by being connected via a contact point 24.

At this time, if the stem 26 is continuously pressed after the movable contact 24 is reversed, the coil spring 25 will be compressed, and the movable contact 24, the central fixed contact 22a and the peripheral fixed contact 22b. The stem 26 is pushed down in a state in which is conducted. By thus compressing the coil spring 25, the overstroke after the movable contact 24 is reversed (after the contact is turned on) is obtained.

[0008]

However, in the structure of the conventional push button switch described above, the stem 2
6, the coil spring 25 is housed inside, and the coil spring 25 is arranged on the movable contact 24.
Since the structure in which the stem 26 is retained and held in 7 is used, there is a problem in that the number of parts is large and assembly is complicated.

Further, since the winding end of the coil spring 25 contacts the movable contact 24, the movable contact 2 is abraded by abrasion.
There was a problem that cracks occurred in No. 4 and were damaged.

Therefore, the present invention solves the above-mentioned problems, reduces the number of parts, facilitates assembly, and prevents wear of the movable contact and improves contact reliability. The purpose is to provide.

[0011]

In order to solve the above-mentioned problems, the first means of the present invention is to provide a housing having an accommodating portion, a fixed contact disposed on the inner bottom surface of the accommodating portion,
A movable contact which is made of an elastically deformable leaf spring and is brought into contact with and separated from the fixed contact; and a movable contact provided on the housing.
A stem that presses the movable contact in a direction of contacting the fixed contact and a cover that is attached to an upper surface of the housing so as to cover the storage portion are provided, and a part of the cover is extended to one end side of the cover. Then, by folding back to the top surface side of the stem, a long operation lever is integrally formed,
This operation lever is characterized in that a stem pressing portion that comes into contact with the top surface of the stem and an elastic arm portion that further extends from this pressing portion are formed.

As a second means, the operating lever is formed to be elastically deformable, and the movable contact is provided between the stem and the inner bottom surface of the housing by the elastic force of the operating lever. It is characterized in that it is sandwiched and elastically biased toward the fixed contact side.

As a third means, the movable contact is formed of a metal spring having a dome-shaped bulging portion, and the lower surface of the stem has a protruding portion for pressing the bulging portion top portion of the movable contact. And the stem pressing portion of the operation lever is disposed on the same axis line corresponding to the protrusion on the lower surface of the stem.

As a fourth means, the operation lever is rotated by the elastic arm portion with the stem pressing portion as a fulcrum as the stem pressing portion presses the stem top surface during the turning operation. It is characterized by elastic deformation in the moving direction.

As a fifth means, an arcuate operating portion is formed on the free end side of the elastic arm portion.

[0016]

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 the push button switch, FIG. 2 is a front view thereof, FIG. 3 is a side view thereof, and FIG.
FIG. 6 is a vertical sectional view showing an operating state of an operating lever.

In the figure, the housing 1 is formed of an insulating material such as synthetic resin into a box shape having a storage portion 1a inside and a rectangular upper surface. A central fixed contact 2a made of a conductive metal terminal material is arranged at the center of the inner bottom surface of the housing portion 1a of the housing 1 in a state of protruding from the terminal material and exposing the upper surface side. Peripheral fixed contacts 2b and 2b, which are also made of a conductive metal terminal material, are disposed at positions facing each other with the central fixed contact 2a interposed therebetween, with the upper surface exposed from the terminal material.
Fixed terminals 3a and 3b are formed at the center of the bottom surface of the housing 1 so as to project outward.

The fixed terminals 3a and 3b are connected to the central fixed contact 2a and the peripheral fixed contact 2b in the housing 1 in a conductive state by the terminal material, and the connecting portion is the housing. It is bent within the housing 1 and is embedded in the bottom of the inside of the housing 1.

The fixed terminals 3a and 3b are formed by projecting outward from the center of the bottom surface of the housing 1 and bending from the projecting base toward the bottom surface along the central side wall of the housing 1. The connection terminals are used by being soldered to a conductive pattern provided on a circuit board on which a push button switch (not shown) is mounted.

Further, on the upper surface side of the housing 1, there are formed locking projections 1b composed of projections at the four corners. The locking projection 1b is engaged with a locking hole 6g of the cover 6, which will be described later, so that the cover 7 is attached to the upper surface side of the housing 1.

The movable contact 4 is formed of a conductive metal plate in a substantially disk shape, and has a dome-shaped bulging portion 4a formed at the center, and the lower surface of the top of the bulging portion 4a serves as the central contact portion. Has become. In addition, the peripheral portion of the movable contact 4 has the peripheral fixed contacts 2b, 2b disposed on the inner bottom surface of the housing 1.
It is placed on b and connected to the peripheral fixed contacts 2b and 2b, and the central contact portion is arranged to face the central fixed contact 2a.

The movable contact 4 is reversed by the central dome-shaped bulging portion 4a being pressed by the stem 5 described later, so that the central contact portion is connected to the central fixed contact 2a. Has become.

The stem 5 is made of an insulating material such as synthetic resin. The stem 5 is provided with a pressing protrusion 5a which is protruded outward from the housing portion 1a of the housing 1 and is pressed. The lower surface of the pressing protrusion 5a is protruded downward. A protrusion 5b is formed which contacts the upper surface of the bulging portion 4a of the movable contact 4 and presses the movable contact 4 downward. A flange 5c is formed on the outer peripheral edge of the pressing protrusion 5a so as to come into contact with the inner surface of the cover 6 to be described later when the stem 5 is pressed.

When the stem 5 is pressed and the stem 5 is returned, the collar portion 5c is moved to the housing 1
The stem 5 is locked to the inner surface of a cover 6, which will be described later, which is fixed to the upper surface of the stem 5 to prevent the stem 5 from protruding outward.

The cover 6 is formed of a plate material such as a metal plate having elasticity, and has a substrate portion 6a formed in a substantially rectangular flat plate shape, and a part of the cover 6 is extended to one end side of the substrate portion 6a. An elongated operation lever 6b which is elastically deformable by folding back the free end side above the pressing projection 5a of the stem 5 in a substantially U shape is integrally provided.

Further, the operation lever 6b has a downwardly projecting stem pressing portion 6c which comes into contact with the top surface of the pressing protrusion 5a of the stem 5, and further extends from the stem pressing portion 6c to be elastically deformable. The elastic arm portion 6d is formed. Further, an arc-shaped operation portion 6e is provided on the free end side of the elastic arm portion 6d, and the operation member 6e is engaged with the driving member D of the electronic device in which the push button switch is mounted to perform the pushing operation. It is supposed to be done.

The stem pressing portion 6c has the movable contact 4
It is formed at an appropriate position of the operation lever 6b so as to come in contact with the upper surface of the bulging portion 4a and press the movable contact 4 downward along the same axis line corresponding to the protrusion 5b of the stem 5. By doing so, the pressing operation force of the operation lever 6b is transmitted from the stem pressing portion 6c to the protrusion 5b on the lower surface of the stem 5 without loss, so that the movable contact 4
The top of the bulging portion 4a can be surely pressed.

The operating lever 6b is elastically deformable, and the elastic force of the operating lever 6b biases the top surface of the pressing projection 5a of the stem 5 downward. It is attached to the upper surface side of the housing 1. With this, the movable contact 4 is sandwiched between the stem 5 and the inner bottom surface of the housing portion 1a of the housing 1, and is elastically biased toward the central fixed contact 2a and the peripheral fixed contact 2b. Therefore, since the pre-stroke can be given to the elastically deformable movable contact 4 in advance, the contact is stable and the switching can be surely performed at the desired switching position.

Further, when the operation lever 6b is rotated, the elastic arm portion 6d is moved by the stem pressing portion 6c as the stem pressing portion 6c presses the top surface of the stem 5. Is formed so as to be elastically deformed in the rotation direction with the fulcrum as a fulcrum. Further, since the arcuate operation portion 6e is provided on the free end side of the elastic arm portion 6d, the drive member D of the electronic device in which the push button switch is mounted is engaged with the operation lever 6b. When the pushing operation is performed, even after the switch is turned on once, the pushing operation can be continued while the switch is turned on, that is, the so-called overstroke operation can be reliably performed.

Further, when the operating lever 6b is pushed by the driving member D, it is rotated along the arc-shaped operating portion 6e, so that the driving member D of the electronic device is operated from the beginning to the end of the operation stroke. It is possible to make sure that it is brought into contact with and pushed in.

Further, the base plate portion 6a of the cover 6 is provided at its center with an insertion hole 6f through which the pressing projection portion 6a of the stem 5 is projected, and the four corner portions of the base plate portion 6a are provided. A locking hole 6g to be engaged with the locking projection 1b formed on the upper surface side of the housing 1 is formed. The locking protrusion 6b of the housing 1 is engaged with the locking hole 6g and caulked by a method such as pressing, so that the stem pressing portion 6c and the projection 5b of the stem 5 are aligned on the same axis. In this state, the cover 6 is fixed to the upper surface side of the housing 1.

Next, the operation of the push button switch having the above structure will be described. As shown in FIG. 4, in the initial state (position indicated by L1 in FIG. 4) when the operation lever 6b is in a non-pressing operation, the elastic force of the operation lever 6b causes the pressing projection 5a of the stem 5 to move upward. Since the surface is always urged downward (position indicated by M1 in FIG. 4), the movable contact 4
The pre-stroke is applied to the movable contact 4, and the peripheral edge of the movable contact 4 is in contact with the upper surfaces of the peripheral fixed contacts 2b and 2b. At this time, the dome-shaped bulging portion 4a is separated from the central fixed contact 4a, and the switch is off.

From this state, when the operating portion 6e of the operating lever 6b is pressed by the driving member D such as an electronic device, it is moved to the position indicated by L2 in FIG. 4, and the stem pressing portion 6c is moved to the stem 5 by the stem pressing portion 6c. The pressing protrusion 5a of FIG.
2 is pushed to the position shown in FIG.
The protruding portion 5b provided below presses the upper surface of the top of the bulging portion 4a of the movable contact 4 and pushes down the bulging portion 4a.

At this time, since the bulging portion 4a of the movable contact 4 is pressed downward, the bulging portion 4a of the movable contact 4 is inverted downward. Therefore, the lower surface of the top of the bulging portion 4a comes into contact with the central fixed contact 2a, and the peripheral fixed contacts 2b, 2b and the central fixed contact 2a are electrically connected via the movable contact 4 so that the switch is operated. Turns on.

From this state, the operation lever 6b is further
When the operating portion 6e of FIG. 4 is pressed by a driving member D such as an electronic device, the elastic arm portion 6d of the operating lever 6b elastically deforms in the rotating direction with the stem pressing portion 6c as a fulcrum (FIG. 4). Position indicated by L3). At this time, on the free end side of the elastic arm portion 6d, the arc-shaped operation portion 6 is formed.
e is provided, and the drive member D is the operation portion 6e.
It is possible to reliably push in the operation stroke from the beginning to the end along the arc surface.

In this way, since the elastic arm portion 6d of the operation lever 6b elastically deforms in the rotation direction with the stem pressing portion 6c as a fulcrum, the state is kept on even after the switch is turned on once (Fig. Since the push-in operation can be continued while keeping the position (denoted by M2 in 4), the overstroke operation can be reliably performed.

When the pressing force applied to the operating lever 6b is released from this state, the operating lever 6b returns to the initial state by its own elastic force, and the bulging portion 4a of the movable contact 4 moves to its own state. It is elastically reversed to return to the initial state, and the urging force at this time pushes the stem 5 upward to return to the initial position. At this time, as the bulging portion 4a is reversed, the lower surface of the top of the bulging portion 4a is separated from the central fixed contact 2a, and the switch is turned off.

According to the above construction, by extending a part of the cover 6 to one end side of the cover 6 and folding it back to the top surface side of the stem 5, the elongated operation lever 6b is formed.
Is integrally formed, and the stem 5 is attached to the operation lever 6b.
And a stem pressing portion 6c that comes into contact with the top surface of the pressing protrusion 5a and pushes the stem 5 for operation.
Since the elastically deformable elastic arm portion 6d extending further from c is formed, the cover 6 and the operation lever 6b are integrally formed, so that the number of parts can be reduced and the assembly is facilitated. It is something that can be done.

Further, the movable contact 4 has the same construction as the conventional one.
Since the upper surface of the top of the above is not directly pressed by a coil spring or the like, but is pressed by the operation lever 6b from the upper surface of the stem 5 via the stem 5, the movable contact 4 is not worn. Further, since the cover 6 closes the opening of the housing portion 1a of the housing 1, the intrusion of dust and the like can be suppressed, and the contact reliability can be improved.

[0040]

As described above, the push button switch of the present invention includes a housing having a housing, a fixed contact disposed on the inner bottom surface of the housing, and a fixed contact made of an elastically deformable leaf spring. One end of the cover is provided with a movable contact that is brought into contact with and separated from the housing, a stem that is vertically movable in the housing and that presses the movable contact in a direction of contacting the fixed contact, and a cover that is attached to the upper surface of the housing so as to cover the storage portion. On the side, a long operation lever is integrally formed by extending a part of the cover and folding it back to the top surface side of the stem, and this operation lever has a stem pressing portion that abuts on the top surface of the stem. Since the elastic arm portion further extending from the pressing portion is formed, the cover and the operating lever are integrally formed, so that the number of parts can be reduced and the assembly can be easily performed.
Also, since the operation lever presses from the top surface of the stem, the movable contact does not wear, and the cover is used to close the opening of the housing to prevent dust from entering and to improve contact reliability. Can be improved.

Further, the operating lever is formed to be elastically deformable, and the movable contact is sandwiched between the stem and the inner bottom surface of the housing by the elastic force of the operating lever to elastically urge the fixed contact side. Therefore, since the pre-stroke can be given to the elastically deformable movable contact in advance, the contact is stable and the switching can be reliably performed at the desired switching position.

Further, the movable contact is formed of a metal spring having a dome-shaped bulge, and a protrusion for pressing the top of the bulge of the movable contact is formed on the lower surface of the stem to push the stem of the operating lever. Since the part is arranged on the same axis line corresponding to the protrusion on the lower surface of the stem, the pressing operation force of the operating lever is transmitted from the stem pressing part to the protrusion on the lower surface of the stem without loss, so that the bulging top part of the movable contact can be secured. It can be pressed.

Further, the operation lever is simple in that the elastic arm portion elastically deforms in the rotational direction with the stem pressing portion as a fulcrum as the stem pressing portion presses the stem top surface during the rotating operation. With the structure, it is possible to reliably obtain an overstroke after the switch is turned on.

Further, since the arcuate operation portion is formed on the free end side of the elastic arm portion, when the operation lever is pushed in by the drive member, it is rotated along the arcuate operation portion. From the beginning to the end of the operation stroke, the drive member can be reliably brought into contact with and pushed in.

[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 front view showing the same push button switch of the present invention.

FIG. 3 is a side view showing the same push button switch of the present invention.

FIG. 4 is a vertical cross-sectional view showing an operating state of the operation lever of the push button switch of the present invention.

FIG. 5 is a vertical sectional view showing a conventional push button switch.

FIG. 6 is a partial cross-sectional view showing a relationship between a movable contact of a conventional push button switch and a coil spring.

[Explanation of symbols]

1 housing 1a Storage section 1b Locking protrusion 2a Central fixed contact 2b Peripheral fixed contact 3a Fixed terminal 3b fixed terminal 4 movable contacts 4a bulge 5 stems 5a Pressing protrusion 5b protrusion 5c Tsuba 6 cover 6a substrate part 6b Operation lever 6c Stem pressing part 6d elastic arm 6e Operation part 6f insertion hole 6g locking hole

Claims (5)

[Claims] 1. A housing having an accommodating portion, a fixed contact disposed on an inner bottom surface of the accommodating portion, a movable contact made of an elastically deformable leaf spring, which comes in contact with and separates from the fixed contact, and moves up and down to the housing. A stem that is movably provided and presses the movable contact in a direction in which the movable contact comes into contact with the fixed contact; and a cover that is attached to an upper surface of the housing so as to cover the storage portion. A long operating lever is formed integrally by extending a part of the stem back to the top surface side of the stem, and a stem pressing portion that abuts the top surface of the stem, and the stem pressing portion. A push-button switch, characterized in that an elastic arm portion extending further from is formed. 2. The operating lever is formed to be elastically deformable, and the movable contact is held between the stem and an inner bottom surface of the housing by an elastic force of the operating lever. The push button switch according to claim 1, wherein the push button switch is elastically biased to the side. 3. The movable contact is formed of a metal spring having a dome-shaped bulging portion, and a protrusion for pressing the bulging portion apex of the movable contact is formed on the lower surface of the stem, and the operation is performed. 3. The push button switch according to claim 1, wherein the stem pressing portion of the lever is arranged on the same axis line corresponding to the protrusion on the lower surface of the stem. 4. The operation lever is elastically deformed in a rotational direction with the stem pressing portion serving as a fulcrum, as the stem pressing portion presses the stem top surface during a rotating operation. The push button switch according to any one of claims 1 to 3, wherein 5. The push button switch according to claim 4, wherein an arcuate operation portion is formed on the free end side of the elastic arm portion.