JP2742136B2 - Rotating variable resistor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a rotary operation type variable resistor such as a semi-fixed variable resistor in which a throttle portion of a slider is crimped with a stopper plate to integrate the two. About.

[Prior Art] Conventionally, semi-fixed variable resistors as shown in FIGS. 6 and 7 have been widely used.

In the figure, a slider 1 is formed by drawing, punching, bending, or the like on a metal plate so that a mounting hole 2a is formed on an inner bottom surface.
2b, a contact portion 3 extending from one side of the throttle portion 2 and slidable on a resistance pattern, which will be described later, and extending from another side portion of the throttle portion 2. The upper plate 4 having an adjustment hole 4a is provided. Resistor substrate 5
An annular resistance pattern (not shown) is formed around the through-hole 5a on the surface of the slider 1. The through-hole 5a faces the mounting hole 2a of the slider 1 mounted on the resistance substrate 5. And the contact piece 3 is elastically contacted with the resistance pattern. Then, a stopper plate 6 made of a metal plate is passed through the through hole 5 a from the back side of the resistance substrate 5, and a pair of locking pieces formed at the end of the stopper plate 6 are formed.
By crimping the periphery of the mounting hole 2a of the slider 1 at 6a, that is, the inner bottom surface 2b of the throttle unit 2, the slider 1 and the stopper plate 6 can rotate integrally with the resistance substrate 5. . In addition, similarly to the upper plate 4 of the slider 1, an adjustment hole 6c is also formed on the back side of the flange 6b of the stopper plate 6.

Numerals 7 to 9 in the drawing denote metal terminals. The metal terminal 7 is sandwiched between the back surface of the resistance board 5 and the flange 6b of the stopper plate 6, and the metal terminals 8, 9 are both ends of the resistance pattern. It is connected to the. Reference numeral 10 denotes a resin case (not shown in FIG. 7) that covers the slider 1. The resin case 10 has an opening 10a through which the adjustment hole 4a of the upper plate 4 is exposed.

After the semi-fixed variable resistor having the above configuration is mounted on the printed wiring board, the adjustment jig such as a driver is
The slider 1 is inserted into the adjusting hole 4a of the upper plate 4 through the opening 10a of the upper plate 4, or into the adjusting hole 6c of the stopper plate 6 from the back side, and the slider 1 is directly or through the stopper plate 6. By appropriately rotating, the contact piece 3 slides on the resistance pattern to change the resistance value.

[Problems to be Solved by the Invention] By the way, in this type of semi-fixed variable resistor, miniaturization has been promoted more and more recently, and the slider 1 having a small inner diameter of the throttle portion 2 has been fixed to the stopper plate 6. It has become difficult to securely caulk and fix with the locking pieces 6a. That is, as shown in FIG. 8, the mounting hole 2a and the side wall 2c of the narrowed portion 2 are
When the locking piece 6a of the stopper plate 6 is bent, the locking piece 6a comes into contact with the side wall 2c, and the locking piece 6a cannot be brought into surface contact with the inner bottom surface 2b of the narrowed portion 2. As a result, the caulking strength is insufficient, and the rotation of the stopper plate 6 causes the slider 1 to rotate.
In other words, the reliability of the slider 1 has to be reduced, for example, there is a possibility that the slider 1 cannot be followed, or there is a possibility that the slider 1 may be loose and the conduction may be poor.

Accordingly, it is an object of the present invention to solve the above-mentioned problems of the prior art and to provide a rotary operation type variable resistor that can securely fix a throttle portion of a slider with a stopper plate even if the size is reduced. Is to do.

[Means for Solving the Problems] An object of the present invention described above is to provide a resistance substrate formed with an annular resistance pattern, and a drawing portion which is drawn in a concave shape and has a mounting hole formed in an inner bottom surface. A slider made of a metal plate placed on the substrate and held rotatably, and slidable on the resistance pattern with a contact piece extending from the throttle portion, a through hole of the resistance substrate and A stopper plate made of a metal plate that penetrates the mounting hole and the locking piece crimps the throttle around the mounting hole, and integrally rotates the slider and the stopper plate to obtain a resistance value. This is achieved by providing an escape window for inserting the locking piece of the stopper plate in the side wall of the throttle portion of the slider in the rotary operation type variable resistor for performing the change.

[Operation] According to the above-described means, even if the inner diameter of the throttle portion of the slider is small, the locking piece of the stopper plate is inserted into the escape window so that it does not contact the side wall of the throttle portion. Thus, the locking piece can be caulked and fixed in a state of being in surface contact with the inner bottom surface of the squeezed portion, and sufficient caulking strength can be obtained.

Example An example of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of a semi-fixed variable resistor according to one embodiment of the present invention, and FIGS. 2 to 5 are manufacturing process diagrams of a slider incorporated in the variable resistor. 6 and 7 are denoted by the same reference numerals, and redundant description will be omitted as appropriate.

As shown in FIGS. 1 and 5, in the semi-fixed variable resistor according to the present embodiment, a pair of escape windows 2d is opened in the side wall 2c of the throttle portion 2 of the slider 1, and these escape holes are opened. Windows 2d are mounting holes
It is located on the extension of the longitudinal direction of 2a. Therefore,
Despite the fact that the inner diameter of the throttle portion 2 has become smaller with the downsizing, the locking piece 6a of the stopper plate 6 is inserted into the escape window 2d at the time of caulking, so that the locking piece 6a contacts the side wall 2c. The surface of the inner bottom surface 2b is brought into contact without contact, and the narrowed portion 2 is securely caulked and fixed.

To manufacture such a slider 1, first, the second
As shown in the drawing, a small hole 12 having an isosceles triangle shape is formed at a predetermined position of a metal plate 11, and the dotted line portion in the drawing is squeezed in a concave shape and pressed to form a hole, as shown in FIG. The metal plate 11 is formed by forming the narrow hole 12 having the mounting hole 2a in the inner bottom surface 2b by forming the small hole 12 into a substantially rectangular escape window 2d, and an arc-shaped portion extending from one side of the narrow portion 2. A contact piece 3 and an upper plate 4 having a substantially cross-shaped adjustment hole 4a extending from the other side of the throttle portion 2;
And processed into a predetermined shape having Next, as shown in FIGS. 4 (a) and 4 (b), the vicinity of the adjustment hole 4a is raised to complete the shape of the upper plate 4, and thereafter, the dotted lines A and B in FIG.
5 (a) and 5 (b), the slider 1 having a desired shape can be obtained.

As described above, in the above embodiment, since the escape window 2d is previously opened in the side wall 2c even if the inner diameter of the throttle portion 2 of the slider 1 is small, the locking piece 6a of the stopper plate 6 is not used. The squeezed portion 2 can be caulked and fixed in a state of being in surface contact with the inner bottom surface 2b,
For this reason, the shortage of swaging strength, which has been concerned with miniaturization, has been resolved. Therefore, in the above embodiment, although extremely small, the slider 1 and the stopper plate 6 are securely integrated, the slider 1 does not rattle, and the semi-fixed variable is highly reliable. Has become a resistor.

In addition, an escape window formed in the side wall 2c of the throttle unit 2 of the slider 1
The shape of 2d and the shape of the small hole 12 for forming the escape window can be appropriately selected, but in order to make it easier to insert the locking piece 6a of the stopper plate 6 at the time of caulking, a substantially square shape as in the above embodiment is used. Escape window
2d is desirable, and in order to form the escape window 2d of such a shape by drawing, it is the experiment of the present inventors that an approximately isosceles triangular small hole 12 as shown in FIG. 2 is optimal. Please note that it has been confirmed by

[Effects of the Invention] As described above, according to the present invention, even if the inner diameter of the throttle portion of the slider fixed to the stopper plate is reduced, the inside of the escape window opened on the side wall of the throttle portion is reduced. The locking piece of the stop plate is inserted into the locking section, and the locking piece can be caulked and fixed in a state in which it is in surface contact with the inner bottom surface of the narrowed portion. A highly reliable rotary operation type variable resistor can be provided.

[Brief description of the drawings]

FIG. 1 is a sectional view of a semi-fixed variable resistor according to an embodiment of the present invention, and FIGS. 2 and 5 show a manufacturing process of a slider incorporated in the variable resistor. FIG. 2 is a plan view of a metal plate before drawing, FIG. 3 is a plan view of a metal plate that has been subjected to drawing and punching, and FIG. 4A is a plan view of a metal plate that has been subjected to primary bending. 4 (b) is a side view of the same, FIG. 5 (a) is a plan view of a slider completed by performing secondary bending, FIG. 5 (b) is a side view thereof, and FIG. FIG. 7 is a cross-sectional view of a semi-fixed variable resistor according to a conventional example, FIG. 7 is an exploded perspective view of the same, and FIG. 8 is a main-portion cross-sectional view for explaining a problem of the prior art. 1 ... slider, 2 ... throttle, 2a ... mounting hole, 2b ... inner bottom surface, 2c ... side wall, 2d ... escape window, 3 ... contact piece, 5 ... resistance board, 5a ... ... through-hole, 6 ... stopper plate, 6a ... locking piece.

Claims (1)

(57) [Claims] 1. A resistance substrate having an annular resistance pattern formed thereon and a constricted portion formed by drawing in a concave shape and having a mounting hole formed in an inner bottom surface are mounted on the resistance substrate and rotatably held. A metal plate slider that allows a contact piece extending from the throttle portion to slide on the resistance pattern, and a through-hole and the mounting hole of the resistance board, and the locking piece is A rotary operation type variable resistor which comprises a metal plate stop plate for caulking the throttle portion around the mounting hole, and changes the resistance value by rotating the slider and the stop plate integrally. A rotary operation type variable resistor, wherein an escape window for inserting the locking piece of the stopper plate is provided in a side wall of the throttle portion of the slider.