JPH03215905A - Small type variable resistor - Google Patents

Abstract

PURPOSE:To satisfy electric characteristics, and to miniaturize the title resistor by a method wherein a bent part is provided on the constricted part of a sliding piece, and the edge face of the bent part is brought into contact with a resistor substrate. CONSTITUTION:The title variable resistor is composed of a resistor substrate 1, having at least a resistor film 1a on the area excluding the circumferential surface of a center hole 1c, a contact part 11a which slidingly moves on the resistor film, and a sliding piece 11 which is rotatably attached to the resistor substrate 1 having a constricted part edge face 11f which is brought into contact with the center hole circumference of the resistor substrate 1. To be more precise, the diameter of the edge face 11f can be reduced to the vicinity of the center hole diameter of the resistor substrate 1 by providing a bent part 11e on the constricted part 11d of a sliding piece 11 and having the bent edge face 11f to come in contact with the resistor substrate 1, and the distance between the edge face 11f and the resistor film 1a can be increased. As a result, electric characteristics of the title variable resistor can be satisfied, and its miniaturizartion can also be achieved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a small variable resistor used in cameras, video tape recorders, and the like.

2. Description of the Related Art A conventional small variable resistor will be explained with reference to FIGS. 2 and 3. FIG. 2 is an exploded perspective view, and FIG. 3 is a side sectional view. In the figure, 1 is a resistor substrate, on which a resistor film 1a, a silver electrode 1b, and a center hole 1c are formed. Note that the resistor film 1a and the silver electrode 1b are provided except for the central hole shown in the figure. Reference numeral 2 denotes a slider, which is formed by a contact portion 2a that slides on the resistor film, a driver groove 2b, a central hole 2c, and a squeeze portion 2d.

Reference numeral 3 designates a middle terminal, which has a fitting part 3a at its center.The eyelet part 3a is inserted into the center hole 1c of the resistor board 1, and the slider 2 is inserted into the protruding eyelet part 3a. Insert the center hole 2c of the slider 2 into the protruding eyelet 3a.
A small variable resistor is formed by rotatably tightening the resistor.

Problems to be Solved by the Invention However, in the conventional small variable resistor described above, the resistor film 1a on the resistor substrate 1 and the squeeze portion 2d of the slider 2
Since the portion B in contact with the resistor substrate 1 is too close to the resistor substrate 1, there is a problem that electrical characteristics such as withstand voltage are not sufficient.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a bending part in the part of the squeeze part of the slider that comes into contact with the resistor substrate,
The end face of the throttle part is brought into contact with the resistor substrate.

Function: As described above, a bent portion is provided in the squeeze portion of the slider, and the bent end surface is brought into contact with the resistor substrate, so that the diameter of the end surface is reduced to near the center hole diameter of the resistor substrate. It is possible to significantly change the distance between the resistor film and the resistor film on the "second resistor substrate", which satisfies the electrical characteristics, and when the distance is the same as that of a conventional small variable resistor. It can be made smaller in comparison.

Embodiment A small variable resistor which is an embodiment of the present invention will be explained with reference to FIG. FIG. 1 is a side sectional view. Note that parts that are the same as those in the prior art are given the same numbers as in the prior art, and description thereof will be omitted. 11 is a slider, and the squeeze part 1 of the slider 11
Bend part at 1d]. 1e, and its end face 11f is brought into contact with the resistor substrate 1.

Effects of the Invention As described above, the squeeze part of the slider has a bent part, and the bent end face is brought into contact with the resistor board, so the diameter of the end face is set to the center hole diameter of the resistor board {=J The distance between the resistor film on the resistor substrate and the resistor film on the resistor board can be increased to meet the electrical characteristics, and the sliding distance between the conventional small variable resistor and the resistor film can be increased. When the distance between the contact portion and the child resistor substrate is the same, it is possible to provide a small variable resistor that is smaller than the conventional one.

[Brief explanation of drawings]

Fig. 1 is a side sectional view of a small town variable resistor which is an embodiment of the present invention, Fig. 2 is an exploded perspective view of a conventional small variable resistor, and Fig. 3 is a sectional side view of the same. be. 1... Resistor board, 1a... Resistor film, 1c... Center hole, 11... Slider, lla... Contact part, lid... squeeze part,]. 1 e...Bending part, ]. 1 f
・・・・・・End face of bent part. rA′1 2 Diagram 3 Diagram

Claims (1)

[Claims] a resistor substrate having a resistor film except for at least the peripheral surface of the central hole; a contact portion that slides on the resistor film; and a resistor having an end surface of a constriction portion that comes into contact with the periphery of the center hole of the resistor substrate. A small variable resistor consisting of a slider rotatably mounted on a body board.