JPH0729452A - Microswitch - Google Patents

Abstract

PURPOSE:To provide a small-sized microswitch applicable to the opening and closing of two high load circuits. CONSTITUTION:A pushbutton having two movable pieces 8, 11 supported by each fixed terminals 3, 5 in such a manner as to be capable of oscillating; at least two fixed contacts 4a, 6b; two movable springs 8a, 88a for snap action; and two pressing parts 7a, 7b is integrated into a resin case 2 to constitute two switch circuits. One switch circuit is arranged in the inner part of the resin case 2 than the other switch circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a micro switch for switching contacts in a snap action manner.

[0002]

2. Description of the Related Art FIG. 3 shows an example of a conventional microswitch.

The microswitch 15 is a normally open type 2
It is a terminal switch, and two fixed terminals 17 and 18 are provided on one end surface of the resin case 16, and a push button 19 is attached to the opposite end surface facing the end surface. It has a structure in which a movable piece 20 for switching contacts operated by a button 19 is incorporated.
The movable piece 20 is integrally formed with a movable spring 20a for snap action for maintaining the contact switching state. The movable piece 20 has its proximal end engaged and supported by one engagement piece 17a provided on the fixed terminal 17, and
The other contact piece 17b has a movable contact 20b of the movable piece 20.
The free end of the movable spring 20a for snap action extending from the side is engaged and supported.

In such a micro switch 15, in a normal state where no external force is applied to the push button 19, as shown in the figure, the elastic restoring force of the movable spring 20a causes the free end side of the movable piece 20 to be urged and displaced upward to abut. Maintained in contact with the piece 23,
When the push button 19 is pushed and the middle portion of the movable piece 20 is displaced downward beyond a certain position, the elastic restoring force of the movable spring 20a is instantly reversed so as to bias the movable piece 20 downward ( Snap action), movable contact 2
0b is contacted with the contact (normally open contact) 18a of the fixed terminal 18 to switch the contact. Then, when the pushing force of the push button 19 is released, the push button 19 is pushed back upward by the elastic restoring force of the movable piece 20, and the elastic restoring force of the movable spring 20a again attaches the free end side of the movable piece 20 upward. It acts in the direction of force and returns to the normal state.

[0005]

However, such a conventional micro switch is a one-circuit switch that opens and closes a load of one circuit, such as an interlock switch for opening and closing a door of OA equipment. When trying to open and close the load of two circuits, such as a drive system such as a motor and a control system such as an operation panel display, two micro switches must be installed to open and close at the same time, which makes installation space and connection complicated. There is a drawback that becomes.

The present invention has been made in view of the above points, and an object of the present invention is to provide a micro switch which is small and can be applied to the opening and closing of two circuits with a high load.

[0007]

According to the present invention, in order to achieve the above-mentioned object, each one end is swingably engaged with and supported by each fixed terminal, and each free end has a movable contact. Two metal movable pieces provided respectively, at least two fixed contacts that are respectively arranged to face each of the movable contacts, and each of the movable contacts come into contact with the movable contact as the movable piece swings, and each of the fixed contacts. Two movable springs made of leaf springs, which are respectively provided between the terminal and each movable piece, and a push button having two pressing portions for pressing and displacing the intermediate portion of each movable piece in the longitudinal direction are made of resin. Two switch circuits are built into the case, one switch circuit is arranged inside the resin case more than the other switch circuit, and both movable pieces are pressed and displaced by the push button. And to perform the contact switching by the said two movable contacts of the two movable spring is snap acting by.

[0008]

According to the above structure, since two push pieces having two movable pieces, at least two fixed contacts, two movable springs and two pressing portions are incorporated in the resin case to form two switch circuits, It can be used to open and close two circuits, and since both contacts can be switched by snap action type, it can be applied to a high load circuit, and one switch circuit is more resin case than the other switch circuit. It is small because it is placed inside.

[0009]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a sectional view of an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the main part thereof.

The microswitch 1 of this embodiment is a four-terminal switch having two normally open type switch circuits. The resin case 2 is provided with four fixed terminals 3 to 6, and a push button 7 is provided. Is pierced from the inside so that it cannot come out.

Fixed terminal 3 constituting one switch circuit
A pair of engaging pieces 3a projecting into the case in, 3b are continuously provided with a predetermined distance, one end of the movable piece 8 in the engaging groove 3 ₁ a which is formed on one engaging piece 3a is engaged and supported with the free end of the movable spring 8a of the snap action consisting of the leaf spring member is engaged and supported so as not to lateral displacement in the engagement groove 3 ₁ b formed on the other engagement piece 3b.

In this embodiment, the movable piece 8 and the movable spring 8a are integrally formed as shown in FIG. One end of the movable piece 8 has an engaging groove 3 ₁ a of the engaging piece 3 a.
The movable contact 8b is formed on the other end side of the movable contact 8b. The movable spring 8a is curved downward from the other end of the movable contact 8b. It is engaged and supported in the engaging groove 3 ₁ b of 3b.

Below the movable contact 8b of the movable piece 8, a fixed contact 4a connected to the fixed terminal 4 is arranged so as to face it, and above the movable contact 8b, the movable contact 8b normally contacts the movable contact 8b. The contact pieces 9 are arranged to face each other.

Further, one pressing portion 7a of the push button 7 biased upward by the spring 10 is in contact with an intermediate portion of the movable piece 8 in the longitudinal direction.

One switch circuit is constituted by the fixed terminal 3, the movable piece 8 integrated with the movable spring 8a, the fixed terminal 4 having the fixed contact 4a, and the one pressing portion 7a of the push button 7.

In this embodiment, the other switch circuit having the same structure is arranged inside the resin case 2 rather than one switch circuit.

That is, the other switch circuit includes a fixed terminal 5 having a pair of engaging pieces 5a and 5b, and a movable spring 11.
a movable piece 11 integrated with a and movable contact 1 of the movable piece 11
The fixed terminal 6 having a fixed contact 6a facing 1b and the other pressing portion 7b of the push button 7 for pressing and displacing the intermediate portion of the movable piece 11 are configured similarly to the one switch circuit, and in particular, In this embodiment, the other switch circuit has a similar shape in which one switch circuit is made smaller.

In the microswitch 1 having the above-mentioned structure, in the normal state where no external force is applied to the push button 7,
As shown in FIG. 1, the push button 7 is in the upper position due to the urging force of the spring 10, and the movable springs 8a and 11a are movable.
Elastic free restoring force biases the free ends of the movable pieces 8 and 11 upward to move the movable contacts 8b and 11b to the contact pieces 9 and 12, respectively.
To maintain contact.

When the push button 7 is pushed in, the intermediate portions of the movable pieces 8 and 11 are displaced downward by more than the set position by the pressing portions 7a and 7b.
The elastic restoring force of a and 11a is reversed so as to bias and move the movable pieces 8 and 11 downward (snap action), and the movable contacts 8b and 11b instantly move to the fixed contacts (normal The open contacts) 4a and 6a are brought into contact with each other.

When the pushing force of the push button 7 is released, the push button 7 is pushed back upward by the spring 10 and is displaced upward by the elastic restoring force of the movable pieces 8 and 11, so that the elastic force of the movable springs 8a and 11a is increased. The restoring force again acts in the direction of urging the free ends of the movable pieces 8 and 11 upward, and returns to the normal state.

As described above, since the microswitch 1 has two switch circuits built therein, it can be applied to an interlock switch for opening / closing a load of two circuits, for example, opening / closing a door of an OA device.

Moreover, since the contacts of both of the two switch circuits are switched by the snap action method, it can be applied to the opening and closing of a high load circuit, and one switch circuit can be made similar to the other switch circuit. Resin case 2
Since it is placed inside, it can be realized in a small size.

In the above embodiment, the movable springs 8a and 11a are used.
Although the movable piece and the movable pieces 8 and 11 are integrally formed, as another embodiment of the present invention, the movable spring and the movable piece are provided separately,
Alternatively, one end of the movable spring may be engaged with the movable piece.

In the above embodiment, the normally open fixed contacts 4a, 6 are provided.
Although only a is provided, as another embodiment of the present invention,
Of course, a normally closed fixed contact may be provided.

[0026]

As described above, according to the present invention, a push button having two movable pieces, at least two fixed contacts, two movable springs and two pressing portions is incorporated in a resin case to form two switch circuits. Since it is configured, it can be used to open and close the load of two circuits with a single switch,
Moreover, since all the contacts are switched in a snap action type, it can be applied to the opening and closing of a high load circuit, and since one switch circuit is arranged inside the resin case more than the other switch circuit, It becomes small.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

FIG. 2 is an exploded perspective view of a main part of FIG.

FIG. 3 is a sectional view of a conventional example.

[Explanation of symbols]

 2, 16 Resin case 3 to 6, 17, 18 Fixed terminal 4a, 6a, 18a Fixed contact 7, 19 Push button 8, 11, 20 Movable piece 8a, 11a, 20a Movable spring 8b, 11b, 20b Movable contact

Claims (1)

[Claims] 1. Two movable pieces made of metal, each one end of which is swingably engaged with and supported by each fixed terminal, and each free end of which is provided with a movable contact, and each of the movable contacts. And at least two fixed contacts, which are arranged to face each other and contact each movable contact with the swing of each movable piece, and made of leaf springs provided respectively between each fixed terminal and each movable piece. Two movable springs and a push button having two pressing portions for pressing and displacing the intermediate portion in the longitudinal direction of each movable piece are assembled in a resin case to form two switch circuits, and one switch circuit is formed. , The switch circuit is disposed inward of the other switch circuit, and the movable springs are snap-operated by pressing and displacing the movable pieces by the push button to move the movable springs. Micro switch which is characterized in that the contact switching by point.