JPH0419762Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to the structure of a variable resistor.

(Prior Art) Conventionally, a variable resistor having a structure shown in FIG. 3 is known.

That is, this variable resistor has a hole 1a in the center of the bottom surface.
The rubber elastic body 7 and the coiled slider 6 are placed in a housing 1 having a projection 5a projecting from the hole 1a in a recess 5b.
A rotor 5 installed in the rotor 5, a resistor and a current collecting electrode body with which the coiled slider 6 is pressed are provided protruding from the resistor substrate 2 printed on the front surface 2a and the back surface 2b of the resistor substrate 2. and the opening 1b of the housing 1 and the resistor board 2.
By filling the adhesive 4 into the recess formed with the back surface 2b and hardening it, the output extraction terminals 8, 8
and the recess 1b of the housing 1 is sealed.

Incidentally, the rotor 5, as shown in FIGS. 4A and B,
A cross-shaped driver groove 5c for resistance value adjustment is carved on the surface of the protrusion 5a, and the surface 5e of the stepped portion 5d maintains a minute distance from the inner circumferential surface 1d of the housing 1 on the hole 1a side. is housed within.

Further, reference numeral 3 denotes an elastic rubber ring which is crimped between the rotor 5 and the resistor board 2 and plays the role of complete sealing, so that unnecessary substances such as dust and grease are removed from the resistor board 2.
This prevents the particles from entering the surface 2a.

(Problems to be solved by the invention) By the way, when manufacturing the conventional variable resistor, a room temperature curing adhesive or a thermosetting adhesive is used as the adhesive 4. Curing adhesives have a long curing time and are low in productivity, while thermosetting adhesives have a short curing time and are low in productivity.
Suitable for fully automatic assembly, improving productivity.

However, with thermosetting adhesive, the inner peripheral wall 1c of the housing 1 and the outer peripheral wall 5f of the rotor 5 are affected by the heat during drying between filling and curing.
The gas in the space E between the housing 1 and the resistor substrate 2 expands, and this gas mixes into the adhesive 4 through the gap (not shown) between the inner peripheral wall 1c of the housing 1 and the resistor substrate 2, causing air bubbles in the adhesive 4. Therefore, there was a problem that adhesive strength and reliability of sealing performance were lowered. The present invention aims to provide a variable resistor that solves this problem.

(Means for solving the problems) As shown in FIGS. 1 and 2 A and B corresponding to the embodiment, the present invention has a hole 1a in the center of the bottom surface and an opening 1b in the top surface. A rotor 9 has a protrusion 9a protruding from a hole 1a in a housing 1, and an elastic body 7 and a coiled slider 6 are installed in a recess 9b, and a resistor with which the coiled slider 6 is in pressure contact. and a current collector electrode body are printed on the surface 2a, and an output extraction terminal 8 provided protruding from the back surface 2b of the resistor substrate 2, and the opening 1b of the housing 1 and In a variable resistor formed by filling a recess formed with the back surface 2b of the resistor substrate 2 with an adhesive 4 for sealing the output extraction terminals 8, 8,
Inner peripheral surface 1 on the hole 1a side at the bottom center of the housing 1
Wide grooves 10, 10 are provided on the surface 9e of the stepped portion 9d of the rotor 9 facing the rotor 9, and an elastic rubber ring 3 is pressed into the space where the rotor 9 and the resistor substrate 2 face each other. This is what was placed.

(Function) According to the present invention, the wide grooves 10, 10 allow
Inner peripheral wall 1c of housing 1 and outer peripheral wall 9 of rotor 9
Since the space E between the space E and the space E can communicate with the outside of the housing 1, when a thermosetting adhesive is used as the adhesive 4, the expanded gas in the space E can be transferred to the wide groove 10, 10 to the outside of the housing 1, so that the expanded gas does not get mixed into the adhesive 4.

(Example) Hereinafter, the present invention will be explained with reference to the drawings. 1, 2A and 2B show an embodiment of the present invention, and 3.
The same parts as those of the conventional example described in FIGS.

The variable resistor according to the present invention is different from the rotor 5 of the conventional example.
This variable resistor is characterized by having the same configuration as a conventional variable resistor except that a rotor 9 is used instead of the rotor 9.

That is, the rotor 9 has the same shape as the rotor 5 of the conventional example, and has a protrusion 9a that protrudes from the hole 1a of the housing 1, and the rubber elastic body 7 and the coiled slider 6 are placed in the recess 9b. It is installed in the housing 1 and housed in the housing 1.

Also, the elastic rubber ring 3 is connected to the rotor 9 as before.
and the resistor substrate 2.

Further, the horizontal groove 9 of the cross driver groove 9c of the protrusion 9a
A wide groove 10,1 is formed on the surface 9e of the stepped portion 9b parallel to g.
0 is set.

As a result, when a thermosetting adhesive is used as the adhesive 4, the wide grooves 10, 10 It can be naturally discharged to the outside of the housing 1 through.

In this embodiment, the wide grooves 10, 1 of the stepped portion 9d
0 is provided in parallel to the lateral groove 9g of the cross driver groove 9c carved in the protrusion 9a of the rotor 9, but the protrusion 9 is not limited to this.
It is sufficient if it is provided on the surface 9e of the step portion 9d with the gap a sandwiched therebetween.

(Effects of the invention) As explained above, according to the invention, a plurality of wide grooves are provided on the surface of the rotor that is in contact with the circumferential surface of the hole at the center of the bottom of the housing of the variable resistor. Since the space is communicated with the outside, (a) it is possible to prevent the generation of air bubbles, which is conventional when using a thermosetting adhesive;

(b) The conventional correction of air bubbles is no longer necessary, and therefore the time required for manufacturing can be greatly shortened, thereby improving the productivity of variable resistors.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing an embodiment of a variable resistor according to the present invention, Figs. 2A and B are a plan view and a right side view of the same rotor, respectively, and Fig. 3 is an example of a conventional variable resistor. The sectional view shown in FIGS. 4A and 4B are a plan view and a right side view of a conventional rotor, respectively. 1...Housing, 2...Resistor board, 3...
Elastic rubber ring, 4... Adhesive, 5, 9... Rotor, 6... Coiled slider, 7... Elastic body, 8...
...Output extraction terminal, 10...Wide groove.

Claims (1)

[Scope of utility model registration request] A housing 1 having a hole 1a at the center of the bottom surface and an opening 1b at the top surface has a protrusion 9a projecting from the hole 1a, and an elastic body 7 and a coiled slider 6 are installed in the recess 9b. A rotor 9, a resistor and a current collecting electrode body with which the coiled slider 6 is pressed are provided protruding from a resistor substrate 2 having a surface 2a printed on it, and a back surface 2b of the resistor substrate 2. A recess formed by the opening 1b of the housing 1 and the back surface 2b of the resistor substrate 2 is filled with an adhesive 4 for accommodating the output extraction terminals 8, 8 and sealing the output extraction terminals 8. In the variable resistor, a plurality of wide grooves 10, 10, . A variable resistor characterized in that an elastic rubber ring 3 is placed in pressure contact with a space where the rotor 9 and the resistor substrate 2 face each other.