JPS62213205A - Miniature variable resistor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a small variable resistor as an electronic component.

(Prior Art) As sets become smaller and cheaper, there is a demand for small variable resistors that are smaller and cheaper. An example of a conventional small variable resistor will be described below with reference to the drawings.

In FIG. 4, a resistor element 1b having silver electrode portions 1a at both ends is formed on the main surface of a resistor substrate 1.
Furthermore, there is a terminal hole 1c in the center of the silver electrode part 1a in which the outer terminal 2 is attached, a notch 1a in the middle of the two silver electrode parts 1a in which the protrusion 3a of the inner terminal 3 is engaged, and a notch 1a in the center of the board. terminal 3
A central hole 1e into which the eyelet portion 3b is inserted is formed. The outer terminal 2 includes a terminal part 2b which is inserted into the terminal hole 1c of the resistor board 1, the part protruding onto the board is fixed by caulking, etc., and is electrically connected to the electrode part 1a by soldering or the like. is formed.

The middle terminal 3 has a resistor substrate 1. An eyelet part 3b that is inserted into the center hole of each of the seat plate 4 and the slider 5, a protrusion 3a that engages with the stopper 68 of the cap 6 stands vertically at the end, and a terminal part 3c stands vertically in the opposite direction. It is formed to do so.

The seat plate 4 is made of synthetic resin and has a central hole 4a through which the eyelet 3b of the inner terminal 3 is inserted. Slider 5
has a central hole 5a in the center through which the eyelet 3b of the intermediate terminal 3 is inserted, and an arm portion 5b that contacts the resistor cord 1b with appropriate pressure and an arm portion 5b formed around the center hole 5a inside the cap 6. A notch 5C is formed to engage with the protrusion 6b. The cap 6 is made of synthetic resin and has a rotation adjustment groove 6C on the top surface.
1 has a cylindrical part 6d in the center of the lower surface thereof, which is inserted into the inner diameter part of the eyelet part 3b of the inner terminal 3. Further, to explain with reference to FIG.
A stopper 68 with which the protrusion 3a comes into contact, and a protrusion 6b that engages with the notch 5C of the slider 5 are provided.

Next, 1. its assembly method will be explained. First, the outer terminal 2 is assembled to the resistor board 1. Next, the resistor board 1 is assembled.
．． Stack the seat plate 4 and the slider 5 in this order, and insert the center hole 1 in each.
Insert the eyelet part 3b of the middle terminal 3 into e, 4a and 5a,
The slider 5 is assembled so that the slider 5 can be freely rotated by caulking the part protruding from the upper surface of the slider 5. Furthermore, insert the cylindrical part 6d of the cap 6 into the inner diameter part of the eyelet part 3d of the inner terminal 3,
The partial hair protruding from the lower surface of the inner terminal 3 is crimped to make the cap rotatable, and the assembly is completed.

In the conventional stopper mechanism, the stopper 6 of the cap 6
8 and the protrusion 3a of the middle terminal 3 come into contact with each other, forming a terminal whose rotation is restricted. FIG. 0 shows a state in which the cap 6 is rotated and the stopper mechanism is activated. To stabilize the stop strength.

When the stopper 6a and the protrusion 3a come into contact, the protrusion 3a
It is necessary that the entire area S of the side surface of the stopper 68 be included within the plane of the stopper 68.

(Problem to be Solved by the Invention) However, the protrusion 3a of the inner terminal 3 may tilt inward due to variations in bending process or unexpected deformation during the assembly process, and the contact area between the stopper and the protrusion S As a result, there is a problem that the stop strength is extremely small, and the number of parts and assembly steps are also large, and the price requested by the user cannot be satisfied. The present invention solves the problems and provides a small variable resistor that constitutes a stable stopper mechanism with fewer parts and satisfies the user's needs.

(Means for solving the problem) Having an arc-shaped through groove in the top plate part covering the resistor element,
In addition, a brush that can rotate once is provided on the cover that also serves as a live power section. This brush has a sliding arm that slides on the resistor element at one end and a protrusion that projects outward from the through groove of the cover at the other end.

(Function) By moving the protrusion protruding from the through-groove of the cover along the through-groove, the brush can be rotated and set to the desired resistance value, and both ends of the through-groove can be moved against the movement of the protrusion. It can be used as a stopper.

(Example) Embodiments will be described in detail below with reference to the five drawings.

FIG. 1 shows an embodiment of the present invention, where 11 is a resistor substrate on which a resistor element 14 is formed and a lead-out terminal 16 is connected to the resistor element 14, and 12 is a live current part. A metal cover 13 which also serves as a brush is rotatably attached to the cover 12 and has a sliding arm 13b at one end that slides over a resistor element formed on a resistor substrate. An arc-shaped through groove 12a is provided in the top plate portion of the cover 12, and a protrusion 13a provided on the brush 13 projects outward through this through groove 12a.

Next, details of each part will be explained. FIG. 2 shows the resistor board 11
and a cover 12 that is placed over this. First, the resistor substrate 11 has a resistor element 14 formed on its main surface, and electrode parts 15 provided at both ends of the resistor element 14.
A terminal 16 for drawing out is connected to each of the terminals 16 and 16 . The outer periphery of the board has a notch Ilb into which the mounting leg 12b of the cover 12 is locked, and a notch lie through which the intermediate terminal 12c extending from the cover 12 passes.

The cover 12 is made of a metal material, and has a mounting leg portion 12b and a middle terminal 12c integrally formed on a rounded outer peripheral portion. There is an arc-shaped through groove 1 in the top plate part of the cover 12.
2a is formed. As shown in FIG. 3, inside the cover 12, a cylindrical part 12d for holding the brush 13 is provided at the center, and a central hole 13c of the brush 13 is fitted into this cylindrical part 12d. The brush 13 is rotatably attached by caulking the tip of the cylindrical portion 12d. A sliding arm 13b that slides on the resistor element 14 extends from one end of the brush 13, and a protrusion 13a that projects outward from the through groove 12a of the cover 12 is provided at the other end. There is.

In this embodiment configured in this way, by moving the protrusion 13a provided on the brush 13 and protruding outward from the through groove 12a of the cover 12 by hand or with a special screwdriver, the resistor element can be moved by the sliding arm 13b. A desired resistance value can be set by changing the contact position on 14. Further, since the movement of the protrusion 13a is stopped at both ends 12f of the through groove 12a, these ends 12f serve as reliable stoppers. Furthermore, the number of parts is reduced to 4 from 6 in the conventional example, greatly simplifying one assembly operation.

(Effects of the Invention) As explained above, according to the present invention, even if the protrusion of the brush is slightly deformed, it can be reliably stopped at both ends of the through-groove of the cover, and the stopper mechanism is structurally robust. In addition, the number of parts can be reduced, assembly can be simplified, and manufacturing costs can be significantly reduced.

[Brief explanation of drawings]

Figure 1 is a sectional view of one embodiment of the present invention, Figures 2 and 3 are
The figure is a diagram showing the configuration of each part of the same embodiment. Fig. 4 is an exploded perspective view of a conventional small variable resistor, Fig. 5 is a view showing the inside of the cap portion, and Fig. 6 is a cross-sectional view showing the stopper mechanism of the conventional example in an activated position. be. 11...Resistor board, 12...Cover, 12a
...through groove, 12c...middle terminal, 13...brush. 13a...Protrusion, 13b...Sliding arm, 14.
...Resistor element, 15... Electrode, 16... Output terminal. Fig. 1 13-,, Brush 16 +++ Drawing paper Fig. 4 Fig. 6

Claims (1)

[Claims] a resistor substrate on which a resistor element is formed; a cover that covers the resistor element portion of the resistor substrate and has an arc-shaped through groove in its top plate portion and also serves as a live current portion; and a top plate of the cover. The brush is rotatably held inside the cover and includes a sliding arm that slides on the resistor element at one end and a protrusion that protrudes outward from the through groove of the cover at the other end. A small variable resistor, characterized in that the resistance value is set to a required value by moving the protrusion, and both ends of the through groove serve as stoppers against the movement of the protrusion.