JPS5828329Y2 - semi-fixed resistor - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a semi-fixed resistor, and more particularly to a mounting structure for a wiper (slider) that slides on a resistor of a small-sized semi-fixed resistor.

Conventionally, semi-fixed resistors having various configurations are known.

For example, as shown in Fig. 1, there are three terminals 1 at the bottom end,
2 and 3, a resistor board 6 and a wiper 7 are provided on the terminals 1 and 3, respectively, on which a resistor 4 whose ends are conductive and a conductive film 5 conductive on the terminal 2 are formed, and the wiper 7 is attached to the eyelet. 8, which is rotatably attached to the substrate 6 is known.

Although the above semi-fixed resistor has a very small number of parts and has a low manufacturing cost, when it is incorporated into a printed circuit board etc. for adjustment, the protrusion 10 that fits into the hole 9 of the eyelet 8
This method has disadvantages in that the position of the wiper 7 must be adjusted using a special screwdriver 12 having a recess 11 into which the wiper 7 is inserted.

As shown in Figure 2, as a solution to the above drawbacks,
Driver insertion pieces 13.13 are provided on both sides of the wiper 7 of the semi-fixed resistor shown in FIG. 15 is known in which the position of the wiper 7 is adjusted.

However, in the semi-fixed resistor shown in FIG.
The blade 16 of the driver 15 is made up of two driver insertion pieces 13.
13, the driver 15
The blade 16 of the blade 16 easily comes off and adjustment work is difficult.

On the other hand, as shown in FIG. 3, a wiper 20 is provided which has a circular hole 17 in the center and a sliding part 19 having an arcuate notch 18 so that both sides thereof can be elastically deformed,
The above-mentioned resistance is achieved by the headed shaft 24 whose shaft portion 21 is formed to have a cross-sectional shape that matches the occluded circular hole 17 and a groove 23 into which the retaining washer 22 is fitted is provided at the tip end, and by the retaining washer 22. The wiper 20 is rotatably attached to the substrate 6 via a spring washer 25, and the elastic deformation of both sides of the sliding portion 19 causes the sliding portion 1
It is known that the resistor 9 is in pressure contact with the resistor 4 so that it can slide.

The semi-fixed resistor shown in FIG. 3 above has an ordinary screwdriver 15 (
Although it is possible to easily move the wiper 20 by inserting the blade 16 (see FIG.
Since it has to be processed so that its cross section has an occluded circular shape, it has the disadvantage of increasing manufacturing costs.

The present invention was made in order to eliminate the above-mentioned drawbacks of conventional semi-fixed resistors, and consists of a piece punched out of an elastic metal plate and having a pointed tip inserted from a part of the circumference of a circular mounting hole. A wiper with a protruding shape is provided, and the biting piece is bitten into the lower surface of the head of a round headed shaft made of a metal material that is softer than the wiper, and the wiper is attached to the resistance board together with the headed shaft. By being rotatably mounted, a screwdriver groove is provided in the headed shaft into which the blade of an ordinary screwdriver can be inserted, and the wiper can be easily moved without using a special screwdriver. To provide a low-cost semi-fixed resistor in which a wiper is attached to a resistor board using a single round headed shaft, thereby reducing the number of parts and the number of man-hours for machining the headed shaft. It is an object.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In FIGS. 4 and 5, 6 has a strip-shaped resistor 4 formed on its surface to form a substantially arc, and a hole 31 for attaching a wiper 30 is provided in the center of the arc. Resistance boards similar to those shown in the figures,
1, 2 and 3 are terminals, and 5 is a conductive film.

The wiper 30 is made by punching out an elastic metal plate, for example, a phosphor bronze plate, and as shown in FIG.
3... are protruded and these biting pieces 3
3.33... is bent upward.

Furthermore, when punching out the wiper 30, a part of the tip thereof is punched out downward into a hemispherical shape, thereby providing the sliding portion 34.

On the other hand, 35 is a headed shaft in which a thick disk-shaped head 37 is formed at one end of a shaft portion 36 having a circular cross section by header processing, etc. A driver groove 26 similar to that shown in FIG. 3 is formed, and a caulking hole 38 having a depth reaching the middle portion of the shaft portion 36 is provided on the tip surface of the shaft portion 36.

The headed shaft 35 has its shaft portion 36 connected to the wiper 30.
through the mounting hole 32 of the resistor board 6 and the hole 31 provided in the resistor board 6,
As shown in FIG. 4, with the biting pieces 33, 33 of the wiper 30 bitten into the lower surface of the headed shaft 35 by pressing or the like, the shaft portion 36 of the headed shaft 35
The wiper 30 is caulked to the resistance board 6 using the caulking hole 38 at the lower end of the wiper 30, and the wiper 30 is attached to the head shaft 3.
It is attached to the resistor board 6 so as to rotate together with the resistor 5.

At this time, the wiper 30 is attached to the resistance board 6 so that the sliding part 34 comes into pressure contact with the resistor 4 due to the elasticity of the wiper 30 itself.
2 and the diameter of the hole 31 of the resistance board 6 on the headed shaft 35.
The diameter of the shaft portion 36 is made equal to the diameter of the shaft portion 36 so that the sliding portion 34 always slides on the same trajectory of the resistor 4.

If the semi-fixed resistor has the above configuration, in order to move the wiper 30, it is sufficient to insert the blade of a normal driver into the driver groove 26 provided in the head 37 of the headed shaft 35 and rotate it. While the wiper 30 can be easily moved with a screwdriver, the manufacturing of the headed shaft 35 is not specifically shown, but since the shaft portion 36 has a circular cross section, the cross section cut to a predetermined length is This can be easily done by inserting a circular wire material such as copper or aluminum into a chuck member, and then inserting a mold to form a head 37 and a mold to form a caulking hole 38 on both end faces of the chuck member, which is called header processing. It can be carried out.

As is clear from the above detailed explanation, the present invention provides a wiper by inserting a cut piece provided in the wiper mounting hole into the lower surface of the head of the headed shaft having a shaft portion with a circular cross section. If you install the wiper on the resistance board so that it can rotate together with the headed shaft, and if you provide a driver groove in the head of the headed shaft to insert the driver blade, you can easily operate the wiper using a regular screwdriver. While it is movable, since a headed shaft with a circular cross section is used, the headed shaft can be easily manufactured by header processing, which is compatible with the small number of parts. Therefore, the production cost of the semi-fixed resistor according to the present invention can be significantly reduced.

[Brief explanation of drawings]

1 and 2 are perspective views of a conventional semi-fixed resistor, FIG. 3 is an exploded perspective view of a conventional semi-fixed resistor, and FIG. 4 is a sectional view of a semi-fixed resistor according to the present invention. FIG. 5 is an exploded perspective view of a semi-fixed resistor according to the present invention. 1.2.3...Terminal, 4...Resistor,
5... Conductive film, 6... Resistance substrate, 26
... Driver groove, 30 ... Wiper, 31 ... Hole, 32 ... Mounting hole, 33
... Biting piece, 34 ... Sliding part, 35
...Shaft with head, 36 ...Shaft part, 3
7... Head, 38... Hole for caulking.

Claims (1)

[Scope of utility model registration request] A resistor board with a resistor having a substantially constant width formed in a substantially circular arc on the surface and a hole in the center of the arc, and a circular mounting hole formed by punching out an elastic metal plate. A wiper having a biting piece with a sharp tip protruding almost perpendicularly to the plate surface of the metal plate and having a sliding portion at the tip that slides on the resistor, and a metal material that is softer than the wiper. and a headed shaft formed so that its shaft portion has a circular cross section, and the headed shaft is inserted into the hole provided in the resistance board and the mounting hole provided in the wiper, and the headed shaft is inserted into the hole provided in the resistance board and the mounting hole provided in the wiper. The tip of the headed shaft is plastically deformed with the biting piece biting into the lower surface of the head of the wiper, and the wiper is attached to the resistance board so as to be rotatable together with the headed shaft. Semi-fixed resistor.