JPS603525Y2 - variable resistor - Google Patents

Description

[Detailed description of the invention] The present invention relates to a rotary variable resistor, and in particular to a slider thereof, in which an elastic contact piece is provided in the center of the slider to increase the sliding torque and stabilize the slider. The object of the present invention is to provide a variable resistor having a sliding torque of 100%.

To explain the variable resistor, an exploded view of an example of a conventional variable resistor without a bearing fitting is shown in FIG.

20 is an insulating substrate with a horseshoe-shaped resistor 22 on its surface.
and a ring-shaped current collector 24 are provided concentrically and insulated from each other, and terminals 3 are connected to both ends of the resistor 22 and the extension of the current collector 24, respectively, forming a resistor substrate 2. .

Reference numeral 5 denotes an operating section, which includes an operating shaft 51, a resistor 22, and a current collector 24.
It consists of a slider 8 having sliding pieces 82 and 84 that make bridging sliding contact with the slider 8, an operating shaft 51 to which the slider 8 is fixed, and a slider receiving portion 52 as one unit.

Reference numeral 6 denotes a cap-shaped case made of a metal plate, which has a central hole 61 on the bottom surface through which the operating shaft 51 projects outward.

Reference numeral 7 denotes a mounting bracket made of a metal plate, with mounting legs projecting downward from the lower part of the side wall 74 bent at right angles, and a hole 71 in the central wall surface into which the small diameter shaft 53 at the end of the operating shaft 51 fits, and a hole 71 in the case 6. A mounting hole 73 that engages with a plurality of mounting legs 63 is provided.

At the opening on the right side of the case 6, overlap the resistance board 20 and the mounting bracket 7, insert the mounting legs 63 of the case 6 into the mounting notch 23 of the resistance board 2 and the mounting hole 73 of the mounting bracket 7, and bend them. It will stick.

In the conventional simple rotary variable resistor without bearings shown in FIG. 1, the rotational torque is generally small because the bearing is omitted, and it has been desired to increase and stabilize the rotational torque.

Particularly when the variable resistor is small, if the sliding pressure including the slider is kept constant, the radius of the sliding portion from the center becomes smaller, so the rotational torque becomes smaller.

The simplest way to counter this is to increase the contact pressure between the resistor sliding piece 82 and the current collector sliding piece 84 of the slider 8, but in a long-term rotational sliding test, the resistor 22, collector sliding piece 84 There was a limit due to wear of the electric body 24, increase in noise, and poor contact.

Another countermeasure is to insert a friction rubber ring or the like into the base of the operating shaft 51 or the small diameter shaft to increase the friction torque, but this method suffers from problems such as deterioration and deformation at high temperatures.

Furthermore, the method of inserting a coil spring has the problem of elastic return rotation, and the plate spring washer used as a countermeasure for this problem often has insufficient elastic performance, and insertion is also troublesome.

In the present invention, this problem was solved by adding and integrally providing an elastic sliding piece in the center of the slider.

Next, an embodiment of the present invention will be explained with reference to FIGS. 2 to 5.

Fig. 2 is a side sectional view of the variable resistor of the present invention, Fig. 3 is a perspective view of the slider, Fig. 4 is a perspective view of the resistor substrate, and Fig. 5A is a plan view of the slider. The mouth shows a side sectional view taken along line XX' in Figure A.

The components other than the slider are the same as the conventional variable resistor shown in FIG. 1, and are designated by the same reference numerals.

The slider 4 of the present invention shown in FIGS. 3 and 5 is made of an elastic metal, and has a resistor sliding piece 42, a current collector sliding piece, etc. compared to the conventional slider 8 shown in FIG. In addition to 44, an elastic sliding piece 46 is provided at the center of the slider.

The slider 4 has an S-symmetrical shape with a slider base 43, a plurality of concentric resistor sliding pieces 42 forming an S-semi-arc shape connected to this, and resistor sliding pieces 42 in the same direction as the slider base 43. is the center part 432 of the slider base 43 forming a concentric semicircle, and the resistor slider 42
A pair of current collector sliding pieces 44 are provided in directions 180° opposite to each other.

Also, in order to prevent mutual entanglement during plating or storage of the slider, one of the pair of current collector sliding pieces 44 has an outer connecting portion with the opposite side of the slider base 43. 45, but this connecting portion 45 may not be provided.

The elastic sliding piece 46 at the center of the slider is ring-shaped and curved downward in a U-shape, and slides into contact near the periphery of the central hole 21 of the insulating substrate 20.

The inner side of the semicircular center portion 432 of the slider base 43 with slider mounting holes 481 and 482 provided at both ends and the connecting portion 46
Connected with 2.

In the present invention, the operating unit 5 is composed of a rotating shaft 51, a slider receiver 52, and a small diameter shaft 53, and a ring-shaped contact portion 5 with as large a diameter as possible is provided on the contact surface between the slider receiver 52 and the bottom surface of the case 6.
There are 4.

In general, in a variable resistor, the resistor sliding piece 42 and the current collector sliding piece 44 are in sliding contact with the resistor 22 and the current collector 24 of the resistance board 2, so accurate positioning is required.

Therefore, in the present invention, the elastic sliding piece 46 is connected to the center of the central part 432 of the slider base 43 by one relatively narrow connecting part 462, so that the influence caused by the elastic deformation of the elastic sliding piece 46 can be ignored. That's what I do.

Further, as shown in FIG. 3, the arcuate central portion 4 of the slider base 43
32 contributes to the elasticity of the elastic sliding piece 46 by torsional stress, but if the elastic sliding piece 46 is twisted counterclockwise when viewed from the connecting portion 462 in advance, the spring characteristics of the elastic sliding piece 46 can be improved. It is also easier to keep the torque constant.

As another embodiment, FIG. 5 8 shows a U-shaped elastic sliding piece 46' that is not ring-shaped, a central part 432' of the slider base, and an elastic sliding piece connecting part 462'.

The assembly of the variable resistor of the present invention is similar to that of the conventional variable resistor shown in FIG.

In the present invention, an elastic sliding piece 46 is provided in the center of the slider in addition to the resistor sliding piece and current collector sliding piece of the slider, so that the friction between the elastic sliding piece 46 and the substrate 20 is reduced. In addition to the torque, the sliding torque of the variable resistor is increased due to an increase in the friction torque of the contact portion 54 of the large diameter slider receiver 52 with the case 6.

Further, the elastic sliding piece 46 is attached to the arcuate center portion 43 of the slider base 43.
2 are connected by a relatively narrow connecting portion 462 at the center thereof, there is little adverse effect due to elastic deformation of the elastic sliding piece 46.

Further, the arcuate central portion 432 of the slider base 43 contributes to the elasticity of the elastic sliding piece 46 due to its torsional stress.

Furthermore, if the arcuate center portion 432 of the slider base 43 is twisted counterclockwise in advance, the spring characteristics of the elastic sliding piece 46 will be improved and the torque can be easily made constant.

[Brief explanation of drawings]

Figure 1 is an exploded view of a conventional variable resistor without a bearing fitting, Figure 2 is a side sectional view of the variable resistor of the present invention, Figure 3 is a perspective view of the slider of the variable resistor of the present invention, and Figure 4 is a perspective view of the slider of the variable resistor of the present invention. The figure is a perspective view of the resistor board of the variable resistor of the present invention, FIG. FIG. 3C shows another embodiment of the elastic sliding piece of the slider of the variable resistor of the present invention. 2: Resistance board, 20: Insulating board, 21: Center hole, 22:
Resistor, 23: Notch, 24; Current collector, 3: Terminal, 4:
Slider, 42: Resistor sliding piece, 422: Resistor sliding piece contact, 43: Slider base, 432: Center part of slider base,
44; Current collector sliding piece, 45: Current collector sliding piece connection portion, 46
: Elastic sliding piece, 462: Elastic sliding piece connecting part, 47: Center hole, 481.482: Mounting hole, 5: Operating part, 51: Operating shaft, 52: Sliding receiver part, 53: Small diameter shaft , 54: contact portion, 6: case, 61: central hole, 63: case leg, 7: mounting bracket, 8: slider, 82: resistor sliding piece, 84: current collector sliding piece.

Claims (3)

[Scope of utility model registration request] (1) A resistor sliding piece 42 that slides on the resistor 22 of the rotary variable resistor resistance board 2, and a current collector sliding piece 44 that slides on the current collector 24 of the resistance board 2.
A rotary variable resistor is equipped with a slider formed from a single elastic plate, and an elastic sliding piece 46 that comes into force-sliding contact around the center hole 21 of the resistor board. (2) The plurality of resistor sliding pieces 42 are composed of closed concentric circular arc pieces, and one of the plurality of current collector sliding pieces 44 is provided with a closed connection part 45 on the outer periphery, and an elastic sliding piece in the center is provided. The variable resistor according to claim 1, wherein the piece 46 is ring-shaped and has a U-shaped slider attached to its lower surface. (3) The inside of the center half of the slider base 43 is concentric with S. On the outside thereof, there are a plurality of arc-shaped resistor sliding pieces 42, and on the opposite side there is one
A pair of opposing N I74 arc current collector sliding pieces 44;
Connecting portion 462 narrower than the center inside the center half of the slider base
The variable resistor according to claim 1, wherein the ring-shaped elastic sliding piece 46 is protruded through the variable resistor.