JPH048588Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a small switch whose installation space can be minimized.

[Conventional technology]

A power switch that is turned on and off by operating the electrical contacts for the keyboard of office automation equipment or the screen opening/closing lid of a small LCD television receiver.
Furthermore, small micro-switches have conventionally been used as power switches that are turned on and off when a car radio's earphones are connected and disconnected.

As shown in Fig. 4, the operating principle of the basic switch, the conventional micro switch 1 has one end of a tension member 2 fixed to a fixed base 3, the other end as a free end, and a movable contact 4 provided at the tip of the tension member 2. One end of a compression member 5 is fixed near the tip of the member 2. The other end of the compression member 5 is held in a compressed state by a receiver 6.

Furthermore, the movable contact 4 is brought into contact with one of the two fixed contacts 8 and 9 by a snap action by the tension member 2 and the compression member 5 in response to the external force 7 applied from the direction perpendicular to the tension member 2. It is configured as follows.

Since such a conventional micro switch 1 switches the contacts using a snap action, it is possible to reliably interrupt and conduct the electrical circuit.
It is widely used in various electronic devices.

[Problem that the invention attempts to solve]

However, although a small-sized micro switch 1 is also available, since the contact is switched by a snap action, the length in the lateral direction with respect to the direction in which the external force 7 is applied by the leaf spring of the tension member 2, etc. The distance l greatly affects the stroke of the movable contact 4.

Therefore, if the tension member 2 or the like is shortened in order to shorten the lateral length l relative to the external force 7, the snap action movement of the movable contact 4 and its contact with the fixed contacts 8 and 9 cannot be ensured. , the reliability of electrical circuit interruption and continuity is reduced.

Therefore, the length of the tension member 2 etc. cannot be reduced much, and the microswitch 1 requires a correspondingly large amount of installation space in a plane orthogonal to the pressing direction.

Along with this, there was a problem that it became a factor that hindered the miniaturization of the equipment and that the switches could not be arranged with a sufficiently high packaging density.

This idea was developed in consideration of the above points, and aims to provide a small switch that can minimize the installation space in the plane perpendicular to the pressing direction and can stably switch the contacts. purpose.

[Means for solving problems]

The small switch of this invention is provided with a movable piece having a recessed portion and a spring piece provided on the fixed terminal side and generating elasticity in the radial direction.

[Effect]

In this invention, during operation, the spring piece of the fixed terminal is inserted into the recess of the movable piece while sliding elastically.

〔Example〕

Hereinafter, embodiments of the small switch of this invention will be described based on the drawings. FIG. 1 is a sectional view showing the configuration of one embodiment. The embodiment shown in FIG. 1 is an on-switch, and has a pipe shape with a total length of about 5 mm, and numeral 11 in the figure indicates the pipe.

This pipe 11 is made of metal, and its outer diameter is 1.5~
It is formed to a diameter of about 5 mm, and an insulator 12 made of a resin material is inserted near the right end of the pipe 1.
At the right end of the insulator 12, the insulator 12 is fixed by a fixing part 11a formed by caulking.

A protruding piece 11b is formed at the right end of this pipe 11. This protruding piece 11b is formed by leaving the right end of the pipe 11 uncut, and is connected to the fixed terminal 13.
and a predetermined circuit.

The fixed terminal 13 is press-fitted into the axial center of the insulator 12 and is fixed therein. This fixed terminal 13 is shown in an enlarged view in Fig. 2a and in Fig. 2b (side view in Fig. 2a).
As is clearer, it is shaped like a phosphor bronze pipe, and the left end has an elastic spring piece 13 with spring properties.
2 to 4 pieces are formed with a left uncut.

The tip of each elastic spring piece 13a is bent into an ``H'' shape to have an insertion guide portion 13b, and the bent portion bent into a ``H'' shape serves as a convex contact portion 13c.

Furthermore, in contrast to the fixed terminals 13 shown in FIGS. 2a and 2b, as shown in FIG. may be formed.

In the case of FIG. 3 as well, the one having the convex contact portion 14c and the insertion guide portion 14 is
This is the same as in Figure b.

Here, the explanation returns to FIG. 1 again. pipe 11
A movable terminal 16 is inserted into the left end side. A stepped portion 16a having a reduced diameter is formed at a predetermined location on the outer peripheral surface of the movable terminal 16. A locking piece 11c is locked to this stepped portion 16a.

This locking piece 11c is formed by constricting the left end of the pipe 11 in the inner diameter direction. By locking the locking piece 11c to the step portion 16a, the movable terminal 16
The movable terminal 16 is prevented from moving leftward beyond a predetermined value and coming out of the pipe 11.

A recessed hole 16b is formed in the shaft center portion on the right end side of the movable terminal 16, corresponding to the elastic spring piece 13a of the fixed terminal 13.

Furthermore, a coil spring 17 is interposed between the insulator 12 and the movable terminal 16 within the pipe 11 . The coil spring 17 is in contact with the inner surface of the pipe 11 with some pressure.

Due to the elasticity of this coil spring 17, the movable terminal 1
6 is always pressed to the left, but as mentioned above, the locking piece 11c locks on the stepped portion 16a so that it does not come off, but against the elasticity of the coil spring 17 When pressing the movable terminal 16 to the right, the stroke is about 1 mm.

Next, the operation of the device configured as above will be explained. In explaining this operation, the relationship between the fixed terminal 13 and the movable terminal 16 will be described using the example of the fixed terminal 13 shown in FIGS. 2a and 2b.

Now, in FIG. 1, when the movable terminal 16 is pressed in the right direction in FIG. 1 against the elasticity of the coil spring 17, a convex portion is inserted from the insertion guide portion 13b of the fixed terminal 13 into the concave hole 16b of the movable terminal 16. Contact part 13c
The elastic spring piece 13a is inserted through.

At this time, the elastic spring piece 13a is inserted while the convex contact part 13c is sliding on the inner surface of the concave hole 16b,
Due to the elastic action of the elastic spring piece 13a, the elastic spring piece 13a elastically presses against the inside of the concave hole 16b.

Furthermore, although the coil spring 17 is compressed, the coil spring 17 may buckle or meander, causing the elastic spring piece 1
In order to prevent the coil spring 1 from coming into contact with
The dimensions of 7 are selected such that it contacts the inner circumferential surface of the pipe 11 with a slight press fit.

As described above, the concave hole 16b of the movable terminal 16
By contacting the elastic spring piece 13a inside, an electrical conduction path is formed between the fixed terminal 13, the elastic spring piece 13a, the movable terminal 16, the pipe 11, and the protrusion piece 11b, and functions as an on-switch.

Therefore, even if the tip of the movable terminal 16 must be partially formed of an insulating material, this can be done depending on how it is used.

This configuration not only allows for miniaturization, but also allows for a current of approximately 50 mA to flow in the energized state, but with simple contacts, sparks are generated at the contact area, which can damage insulating films such as oxide films. If this occurs at the contact portion and causes poor conduction or an extremely high resistance value, it will lack durability.
c is in pressure contact and the contact surface is cleaned by repeated sliding, so the above-mentioned drawback can be improved, and when conducting, the elastic spring piece 13 is inserted into the recessed hole 16b around the movable terminal 16.
a is inserted and becomes an integral part, so the movable terminal 16
It is possible to prevent rattling caused by the clearance of the sliding surface with respect to the inner surface of the pipe 11.

Accordingly, this type of switch, in which even the slightest error can affect operational accuracy, is durable, and guarantees reliable and highly accurate operation.

[Effect of idea]

As described above, according to the small switch of this invention, the elastic spring piece that generates elasticity in the radial direction provided on the fixed terminal is inserted into the recessed hole of the movable terminal while sliding elastically. It can be made smaller, the contact surface between the movable terminal and the fixed terminal can be refreshed, the oxide film can be removed, and the durability of conduction can be improved.

In addition, there is no play in the push operation of the movable terminal.
Stable operation is guaranteed and operation accuracy is high, making it suitable for this type of extremely small switch.

[Brief explanation of drawings]

Fig. 1 is a sectional view of one embodiment of the small switch of this invention, Fig. 2a is an enlarged front view of the fixed terminal portion of the same embodiment, Fig. 2b is a side view of Fig. 2a, and Fig. 3 The figure is an enlarged front view of another embodiment of the fixed terminal in the small switch of this invention, and FIG. 4 is a functional explanatory diagram of the conventional switch. 11...Pipe, 11b...Protrusion piece, 12...
Insulator, 13... Fixed terminal, 13a, 14... Elastic spring piece, 13b, 14a... Insertion guide part, 1
3c, 14c... Convex contact portion, 16... Movable terminal, 16a... Step portion, 16b... Recessed hole, 17...
coil spring.

Claims (1)

[Scope of utility model registration request] A conductive pipe, a fixed terminal that is inserted into one end of the pipe through an insulator and has a plurality of elastic spring pieces at its tip that are elastic in the outer diameter direction, and is movably inserted into the other end of the pipe. a movable terminal having a concave hole into which the elastic spring piece is inserted while in sliding contact when the movable terminal is in operation, and a movable terminal and a fixed terminal interposed between the insulator and the movable terminal in the pipe and when the movable terminal is not in operation. A small switch consisting of a coil spring that separates.