JPS598265Y2 - switch device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a switch for controlling the speed of, for example, an electric tool, and particularly relates to an improvement of a switch device that takes measures to prevent noise from being applied to other electric appliances.

FIG. 1 shows a well-known switch device, in which 11 is a box;
12 is the cover.

The inside of the box 11 is partitioned by a partition wall 13, and a common contact piece 14 is provided at the inner bottom of the box 11 located at the front in the figure.
, a first fixed contact piece 15, and a second fixed contact piece 16 are provided.

Furthermore, a sliding resistance (not shown) is provided on the back surface of the partition wall 13.

A shaft portion 18 of an operator 17 that drives the sliding resistor and a movable contact piece to be described later is provided on the cover 12 so as to be freely removable.

A coil spring 19 is interposed between the end surface of the shaft portion 18 and the inner wall surface of the cover 12 to bias the operator 17 in the projecting direction.

On the other hand, 20 is a contact, and this contact 20 has a protrusion 2.
1 is provided.

One end portion of a movable contact piece 22 is rotatably provided on this protrusion 21 .

The upper end of one end of the movable contact piece 22 is engaged with the shaft portion 18 of the operator 17, and the other end is always urged toward the inner bottom of the box 11 by a spring 23.

Further, the common contact piece 14 is connected to a terminal 24, and the first
The fixed contact piece 15 is connected to a terminal 26 via a capacitor 25 for noise prevention.

Further, the first fixed contact piece 15 is connected to the second fixed contact piece 16 and a terminal 28 via a control circuit 27 comprising, for example, a thyristor and the aforementioned sliding resistor.

A power supply 29 is connected to the terminals 24 and 26, and the terminal 26
．． A motor 30 of, for example, an electric tool is connected to 28.

In the above structure, when the operator 17 is driven in the direction of arrow A in the figure, the other end of the movable contact piece 22 comes into contact with the first fixed contact piece 15, and the power supply 29 is supplied to the motor 30 via the control circuit 27. Ru.

In this state, when the operator 17 is further driven in the direction of arrow A, the resistance value of the sliding resistance is varied, the conduction angle of the thyristor is controlled, and the rotational speed of the motor 30 is increased.

Then, when the other end of the movable contact piece 22 slides onto the second fixed contact piece 16, maximum power is supplied to the motor 30.

Further, at this time, the contactor 20 short-circuits the common contact piece 14 and the first fixed contact piece 15.

Therefore, the capacitor 25 prevents noise generated by the motor 30 from flowing into the power supply 29.

By the way, in the above structure, the movable contact piece 22 is placed on the protrusion 21 of the contactor 20, and the common contact piece 14 and the movable contact piece 22 are electrically connected via the contactor 20.

In other words, the contactor 20 is part of the main current section.

Furthermore, since the contactor 20 and the movable contact piece 22 are in point contact, the contact is unstable, and there is a drawback that the temperature rise at the contact portion is large.

Further, the work of engaging the movable contact piece 22, one end of which is engaged with the shaft portion 18 of the operator 17, with the contact member 20 and the protrusion 21 is extremely complicated. 20, it is difficult to improve vibration resistance.

This idea was made based on the above circumstances, and by providing an elastic contactor in the middle of the movable contact piece, it not only prevents noise when maximum power is supplied, but also allows the main power section to be composed of only the movable contact piece. This aims to provide a switch device that can maintain contact stability, suppress temperature rise, is easy to assemble, and has excellent vibration resistance.

An embodiment of this invention will be described below with reference to the drawings.

In FIG. 2, 31 and 32 are a box and a cover that constitute a switch case, respectively.

A shaft portion 34 of an operator 33 is provided on this cover 32 so as to be able to move in and out.

A return spring 35 is interposed between the end surface of the shaft portion 34 and the inner surface of the cover 32.
And the shaft portion 34 is urged in the protrusion direction.

A locking step 36 is provided on the shaft portion 34, and the step 36 engages with a protrusion 37 provided on the inner surface of the cover 32 to define the protruding position of the operator 33.

On the other hand, the inside of the box 31 is partitioned by a partition wall 38, and the inner bottom of the box 31 located at the front in the figure has a common contact piece 39, a first fixed contact piece 40, and a second fixed contact piece 41 in order along the longitudinal direction. are provided at predetermined intervals.

Furthermore, a sliding resistance (not shown) is provided on the back surface of the partition wall 38.

The common contact piece 39 has a through hole 4 at one end as shown in FIG.
2 is provided, and projections 43 and 44 are cut and shaped at the other end.

In addition, a tongue portion 45 is bent at a predetermined angle in the through hole 42, and a contact piece 46 is provided between the protrusion 43 and the tongue.
extends in the direction of the first fixed contact piece 40.

The through hole 42 is located at the opening of a recess 47 provided at the inner bottom of the box 31, and the tongue 45 is brought into contact with the wall of the recess 47.

A movable contact piece 48 is provided on the common contact piece 39.

As shown in FIG. 3, this movable contact piece 48 has one longitudinal end central portion 49 bent downward, and both side portions 50 and 51 curved slightly upward.

Further, a through hole 52 is provided in the middle portion, and the other end portion 53 is bent downward into a substantially L-shape.

A notch hole 54 is provided in the vertical surface of this L-shaped portion.

Furthermore, the movable contact piece 48 is provided with a contactor 55 .

As shown in FIG. 3, this contactor 55 is provided with four points 56 in the center thereof which are fitted into the through holes 52 of the movable contact piece 48, and the end portions 57 are fitted into the notch holes 54 of the movable contact piece 48. It is bent downward so that it can be inserted.

This bent portion has elasticity.

The tip of the actuator 58 is engaged with the recess 56 of the contactor 55 .

The base end of the actuator 58 is fitted into a recess 59 provided in the shaft portion 34 of the operator 33 so as to be freely removable and removable. It is biased in the protruding direction by the interposed coil spring 61.

Note that the common contact piece 39, the first and second fixed contact pieces 40
, 41 are not shown, but as in FIG.
A control circuit 27, a power supply 29, and a motor 30 are connected.

The operation in the above structure will be explained.

Normally, the operator 33 is in a protruding state as shown in FIG.
At this time, the middle part of the movable contact piece 48 is connected to the protrusion 43 of the common contact piece 39. 44, and the through hole 42 of the common contact piece 39 and the box 3
1 into the recess 49, and both side portions 50, 51 are brought into contact with the common contact pieces 39 located on both sides of the through hole 42.

Therefore, the other end of the movable contact piece 48 and the contactor 55 are separated from the first and second fixed contact pieces 40, 41, and the switch state is in the OFF state.

When the operator 33 is pulled in from this state against the biasing force of the return spring 35, the movable contact piece and the contact 55 are moved to the operator 58.
moved by

That is, the movable contact piece 48 and the contactor 55 are connected to the protrusions 43 and 44.
The actuator 58 slides in contact with the protrusion 43.4.
4, the movable contact piece 48 is rotated about the projections 43, 44 as shown in FIG. 4a.

Therefore, the other end 53 of the movable contact piece 48 comes into contact with the first fixed contact piece 40, and the switch state is turned on.

In this state, when the operator 33 is further pulled in, the center portion 49 of one end of the movable contact piece comes into contact with the tongue portion 45 of the common contact piece 39, as shown in FIG. 4b, and at the same time, one end of the movable contact piece Both sides 50, 51 of the projection 43. 44.

Therefore, the on state of the common contact piece 39 and the first fixed contact piece 40 is maintained.

Further, at this time, the contactor 55 slides together with the movable contact piece 48, and the end portion 57 comes into contact with the first fixed contact piece 40.

When the operator 33 is further pulled in, the center portion 49 of one end and the other end 53 of the movable contact piece 48 are slid on the contact piece 46 of the common contact piece 39 and the first fixed contact piece 40, respectively. As shown in Figure C, the other end 53 of the movable contact piece 48
is brought into contact with the fixed contact piece 41, and the maximum power is supplied.

At this time, the contactor 55 is slid on the first fixed contact piece 40,
The first fixed contact piece 40 and the common contact piece 39 are maintained in a conductive state.

Therefore, as in the conventional case, the capacitor prevents noise generated by the motor from flowing into the power supply.

In the above state, when the pulling force of the operating element 33 is released, the operating element 33 is returned by the return spring 35.

Along with this, the movable contact piece 48 and the contactor 55 perform operations in reverse order to those described above, and return to the OFF state shown in FIG. 2.

According to the above structure, the movable contact piece 48 is provided with the contact 55,
The common contact piece 39 and the second fixed contact piece 41 are the movable contact piece 48
In the electrically conductive state, the end portion 57 of the contactor 55 and the center portion 49 of one end portion of the movable contact piece 48 are short-circuited to the first fixed contact piece 40 and the common contact piece 39, respectively.

Therefore, as in the conventional case, it is possible to prevent noise from going around, and since the main current section is composed of only the movable contact piece 48, the stability of contact can be maintained and temperature rise can be suppressed.

Furthermore, since the contactor 55 has a structure in which the recess 56 and the end portion 57 are respectively fitted into the through hole 52 and the notch hole 54 of the movable contact piece 48, assembly is easy. The end portion 57 of the contactor 55 has elasticity while making contact.

Therefore, the stability of the contact with the first fixed contact piece 40 can be ensured, and the vibration resistance is also excellent.

Note that this invention is not limited to the above embodiments,
For example, as shown in FIG. 5, the contact 60 may be fixed to the center portion 49 of one end of the movable contact piece 48 by caulking.

In this case, the through hole 52 of the movable contact piece 48 is used as the recess 61, and the notch hole 54 is unnecessary.

Even with such a structure, the same effects as in the above embodiment can be obtained.

It goes without saying that various other modifications can be made without changing the gist of the invention.

As detailed above, this invention not only prevents noise, but also maintains contact stability by configuring the main conductor part with only a movable contact piece, suppresses temperature rise, and simplifies assembly. A switch device with excellent vibration resistance can be provided.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway side view showing an example of a conventional switch device, FIG. 2 is a partially cutaway side view showing an embodiment of the switch device according to this invention, and FIG. 3 is a partially cutaway side view showing an example of a conventional switch device. An exploded perspective view showing the main parts taken out, Figures 4a, l) and c are partially cutaway side views shown to explain the operation of Figure 2, respectively, and Figure 5 is another embodiment of the invention. FIG. 31...Box, 32...Cover,
33...Operator, 39...Common contact piece, 40.41...First and second fixed contact piece, 4
8...Movable contact piece, 50. 60...Contact child.

Claims (1)

[Scope of utility model registration request] A common contact piece and first and second fixed contact pieces are arranged along the operating direction of the operator, and the common contact piece and the first and second fixed contact pieces are arranged in accordance with the operating state of the operator. In a switch device in which the connection state is switched by a movable contact to vary the power supplied to the controlled device, and the common contact and the first fixed contact are connected when maximum power is supplied to prevent noise, A movable contact whose one end is always in sliding contact with the common contact according to the operating state, and a movable contact that is provided on this movable contact and which is connected to the common contact and the second fixed contact, and the common contact is connected to the common contact. A switch device comprising an elastic contact that short-circuits a contact piece and a first fixed contact piece.