JPH0741124Y2 - Resistor board for variable resistor - Google Patents

Description

TECHNICAL FIELD The present invention relates to a resistance substrate for a variable resistor in which a conductor, a resistor, and a terminal are integrally molded.

Conventional Technology Conventional technology will be described with reference to FIGS. FIG. 3 is a front view of the resistance substrate, and FIG. 4 is an enlarged cross-sectional view in the vicinity of the terminal embedding portion which is a main part of FIG. Conventionally, a resistance substrate of this type has a desired resistance value (generally composed mainly of a carbon paste) and a resistor body 2 thereof, as described in Japanese Patent Publication No. 60-51241. A conductor 3 (generally composed mainly of silver paste) formed at both ends and a terminal 4 are provided on the conductor 3. By integrally molding these with a plastic material, the terminal 4 becomes a resistance substrate. It is embedded in 1 and fixedly joined to the conductor 3. Further, the tip of the terminal 4 is processed into a tapered shape so that the conductor 3 is not cut when the terminal is embedded.

However, in the above-mentioned conventional resistance board, the method of processing the tip portion of the terminal 4 into a taper shape is produced by a press die or the like, so that the deformed portions 4a, 4b near the tip portion due to burrs or the like are formed. However, there is a problem in that the electric conductor 3 is easily cut and the electric conductor 3 is cut into the joint surface with the electric conductor 3 and the electric conductor is cut.

In addition, since the conductor is generally formed of a material mainly composed of silver paste, there is a problem that the conductor exposed on the surface of the resistance substrate 1 is sulfided and transformed into an insulator.

The present invention solves such a conventional problem,
An object of the present invention is to provide a resistance substrate which can maintain a stable electrically conductive state without cutting the conductor.

Means for Solving the Problems In order to solve the above problems, the present invention provides a part of a conductor with a joint with a terminal, and the rest is overcoated with a resistor.

Therefore, according to the present invention, a part of the conductor is provided with a joint with the terminal, and the other part is overcoated with a resistor to form the terminal tip in two layers, so that the vicinity of the tip of the terminal is provided. Even if a deformed portion due to burrs or the like is generated, the conductor is not cut and an electrically stable conductive state can be maintained.

Embodiment An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a plan view of the resistance substrate, and FIG. 2 is an enlarged cutaway view of the vicinity of a terminal embedding portion which is a main part of FIG. The same parts as those of the conventional example will be given the same reference numerals and will be described with reference to FIGS.
As shown in the figure, a resistor 2 having a desired resistance value, a conductor 3 formed on both ends of the resistor 2, and a terminal 4 on the conductor 3 are integrally molded with a plastic material. As a result, the terminal 4 is embedded in the resistance substrate 1.
At this time, the resistor 2 overcoats the entire area of the conductor 3 except the plane joint 3a with the plane 4c of the terminal 4,
Therefore, the tip portion of the terminal 4 is constituted by bonding two layers of a conductor and a resistor. As described above, according to the above-described embodiment, even if the deformed portions 4a and 4b near the tip of the terminal are embedded in the resistor 2 when the terminal 4 is buried, the conductor 3 is not affected at all. Further, since the conductor 3 and the terminal 4 are securely joined to each other at the flat joint portion 3a where the resistor 2 is not overcoated, the conductor 3 is not cut as a result, and the electrical contact is prevented. In addition, it has the effect of maintaining a stable junction conduction state.

Effect of the Invention As is apparent from the above-described embodiments, the present invention is one in which almost all the area except for a part of a plane joint of a conductor with a terminal is overcoated with a resistor, and a deformed portion is embedded in the embedded terminal. Even if there is, there is no fear of cutting the conductor, and there is a remarkable effect that a stable junction conduction state can be obtained. Further, since the overcoating with the resistor can be performed in the process of forming the conventional resistor, no additional man-hours are required and the overcoating can be easily performed.

Further, since the conductor is overcoated with the resistor, it is not exposed on the surface of the resistance substrate, and therefore, the harmful effect due to sulfuration or the like can be avoided.

[Brief description of drawings]

FIG. 1 is a plan view of a resistance substrate according to an embodiment of the present invention,
2 is an enlarged cross-sectional view of a main part of the same substrate, FIG. 3 is a plan view of a conventional resistance substrate, and FIG. 4 is an enlarged cross-sectional view of the same. 1 ... Resistor substrate, 2 ... Resistor, 3 ... Conductor, 3a ...
Flat joint, 4 …… Terminal.

Claims (1)

[Scope of utility model registration request] 1. A resistor having a desired resistance value on its surface, conductors formed at both ends of the resistor, and terminals joined on the conductor, all of which are integrally molded. A resistance substrate for a variable resistor, wherein the conductor is overcoated on substantially the entire surface of the resistance substrate for the variable resistor, except for a planar joint portion in contact with the terminal.