JPS5848973B2 - trigger switch - Google Patents

Description

[Detailed description of the invention] The present invention relates to a trigger type switch.

Conventionally, in a trigger type switch, as shown in FIG. 1, a trigger 2 is rotatably attached to a pin 3 in a case 1, and a trigger 2 is attached to the trigger 2 at a position away from the pin 3. An actuating plate 5 is rotatably attached by a pin 4.

By pushing the trigger 2 against the biasing force of the compression spring 6, the actuating plate 5 is moved to the right in the constant stroke diagram along the case 1.

On the other hand, a shaft 7 swingably provided in the case 1
A compression spring 10 is fitted between a claw 8 that is swingably attached to the shaft 7 and a projection 9 provided on the actuating plate 5, so that when the actuating plate 5 moves, it swings together with the shaft 7 via the compression spring 10. The movable contact plate 11 is moved in the opposite direction to the operating plate 5 by the movable claw 8, and the fixed contact pieces 13 and 14 are turned on and off by the movable contact piece 12 provided on the movable contact plate 11. There is.

By the way, in the trigger type switch, the movable plate A is composed of the shaft 7, the pawl 8, and the movable contact plate 11, and the pawl 8 has a movable contact piece 12 and a fixed contact piece 13, 14. Compression spring 1 due to arc on and off with
0 and the shaft 7 from being burnt out.
This has the disadvantage of requiring a large number of parts and complicating assembly work.

In addition, since the shaft T and the pawl 8 perform rocking motion, and the movable contact plate 11 performs linear motion, the amount of movement of the actuating plate 5 is not accurately transmitted to the movable contact plate 11, resulting in reliable switch switching. It had the disadvantage of being of low quality.

The present invention has been made in view of the above-mentioned drawbacks, and its purpose is to simplify the assembly work by reducing the number of structural parts of the movable plate, eliminate the need for a separate shield plate, and ensure reliable switching of the switch. The aim is to provide a highly reliable trigger type switch that can perform the following functions.

The present invention will be explained below with reference to embodiments shown in the drawings.

In FIG. 2, 20 is a pin 22 attached to the switch case 21.
The trigger is rotatably attached to the trigger, and a compression spring 23 for return is fitted inside the trigger.

Reference numeral 24 denotes an actuating plate rotatably connected by a pin 25 at a position slightly apart from the pin 22 of the trigger 20, and a projection 26 made of a separate member is provided downward at a predetermined position.

When the trigger 20 is pushed in against the biasing force of the compression spring 23, the actuating plate 24 is activated by the case 21.
Move to the right in the constant stroke diagram along the lower part.

27 is fitted into the case 21 described in (7);
This movable plate 27 is a movable plate that swings in conjunction with the movement of 4.
is integrally molded with resin, as shown in Figure 3.
Opposing fan-shaped side wall parts 29 and 30 are connected by a shielding part 28 to form an ffiH shape.

Then, each side wall portion 29. At the top of 30, supporting protrusions 29a and 30a are provided facing outward, and
Notches 29b and 30b are provided in the arc portions of the side wall portions 29 and 30.
A movable contact piece 3 whose front and back surfaces are continuous is provided below the shielding part 28 on the trigger 20 side from the notches 29b and 30b.
1.32 is installed.

-E The protrusions 29a and 30a are each swingably inserted into a recess 33 provided on the upper surface of the case 21 at a position a certain distance away from the protrusion 26 of the actuating plate 24 toward the trigger 20.

Furthermore, a protrusion 28a is provided approximately in the center of the shielding portion 28, facing the protrusion 26, and each protrusion 26, 28a
Under normal conditions, the opening plate 27 is biased counterclockwise by the compression spring 36 fitted through the receivers 34 and 35, and is in the state shown in FIG.

Reference numerals 37 and 38 denote fixed contact pieces provided at the front and rear ends of the case 21, and their tips face each other at a predetermined interval in the center of the case 21.

Side wall portions 29 and 30 of the movable plate 27 below the shielding portion 28 are positioned in pressure contact between the fixed contact pieces 37 and 38, respectively.

In the above configuration, when the trigger 20 is in the non-operated state, the actuating plate 24 is in the state shown in FIG. 2, and the projection 26 is located at the rear end of the recess 33 of the case 21.

Therefore, the movable plate 27 is swung counterclockwise around the protrusions 30a and 29a by the biasing force of the compression spring 36, and the movable contact piece 31.32 is moved from the fixed contact piece 37.3.
8, and the fixed contact pieces 37, 38 are in a non-contact (off) state by sandwiching the side wall portions 29, 30 (FIG. 4A).

In this state, when the trigger 20 is pushed toward the case 21 against the biasing force of the compression spring 23, the actuation plate 24 moves by a certain stroke to the right in FIG. 2 along the case 21.

By this movement of the actuating plate 24, the force of the protrusion 26 is released and the pivoting plate 27
When the movable plate 27 is moved to the right from the line connecting the protrusions 29a, 30a and 28a, the movable plate 27 is biased clockwise.

That is, the movable plate 27 rapidly swings clockwise around the protrusions 29a and 30a, and the movable contact pieces 31 and 32
is located between the fixed contact pieces 37 and 38, and the fixed contact pieces 37
．． 38 makes contact via the sliding contact pieces 31 and 32, and the switch is switched from the off state to the on state (fourth diagram)
.

As mentioned above, the movable contact pieces 31 and 32 are connected to the fixed contact piece 3γ.
, 38, an arc is generated, but this arc does not reach the compression spring 36 due to the presence of the shielding portion 28.
Burnout of the compression spring 36 due to arcing is reliably prevented.

Next, when the pressing force of the trigger 20 is released, the trigger 20 returns to its original position due to the urging force of the compression spring 23, and along with this, the actuating plate 24 returns to its original position.

Then, the protrusion 26 of the operating plate 24 is connected to the protrusion 29 of the moving plate 27.
When moving to the left of the line connecting 28a, 30a and 28a, the movable plate 27 swings counterclockwise again.

Therefore, the movable contact pieces 31.32 are fixed contact pieces 37.
38 to the upper side of the fixed contact piece 37. 38 becomes the non-contact state again, and the switch changes from the on state to the off state (Fig. 4A).

As described above, according to the trigger type switch of the present invention, the movement plate having the movable contact piece that turns on and off the fixed contact piece in conjunction with the actuation plate is swingably supported by the case at one end. The opposing side walls and the shielding part that connects them and shields the compression spring from the fixed contact piece are integrally formed using synthetic resin, so the number of parts is extremely small compared to conventional products, simplifying the assembly process. In addition, by the movement of the actuating plate described in (h), the movable plate can be swung through only the compression spring to turn on and off the movable contact piece and the fixed contact piece, so that the switch can be switched accurately; This not only improves the reliability of switch operation, but also prevents the compression spring from burning out due to the arc that occurs when the contact piece turns on and off.
This can be prevented without providing any special members.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view showing the configuration of a conventional trigger switch.
FIG. 2 is a vertical cross-sectional view showing the configuration of one embodiment of the present invention, and FIG.
This figure is an enlarged perspective view of the movable plate shown in FIG. 2, and FIGS. 4A and 4B are cross-sectional views taken along the line IV--IV in FIG. 20...Trigger, 24...Operating plate, 22
7... Movable plate, 28... Shielding part, protrusion, 29, 30... Side wall part, 29a... Protrusion, 31, 32... Movable Contact piece, compression spring, 37,
38...Fixed contact piece. 6... Protrusion, 28a..., 30a... 36... Pressure

Claims (1)

[Claims] 1. An actuating plate that moves a certain stroke relative to the case when the trigger is operated, a movable plate that is swingably supported at one end by the case and has a movable contact piece on the other end, and the actuating plate and the movable plate. The movement of the actuating plate based on the trigger operation causes the movable plate to swing via the compression spring, and the movable contact piece turns on the fixed contact piece placed opposite the movable contact piece. - In a trigger-type switch that turns off, the movable plate is connected to an opposing side wall portion that is swingably supported by the case at its tip, and a compression spring is connected to the movable and fixed contact pieces. The movable plate swings to form a fixed contact piece on a part of the end opposite to the swing fulcrum of the side wall. A trigger-type switch characterized by having a movable contact piece that turns on and off.