JPH0119370Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a small variable resistor that is used by being attached to a printed circuit board or the like.

Prior Art For example, as shown in FIGS. 1 and 2,
A circular hole 3 is provided in a resistance substrate 2 having an arcuate resistance film 1 formed on its surface, a wiper mounting hole 6 provided in a terminal plate 5 having two terminals 4, and the circular hole 3 in the resistance substrate 2.
, place the terminal board 5 on the back side of the resistor board 2, insert the cut and raised piece 8 provided on the wiper 7 into the wiper mounting hole 6 of the terminal board 5, and then There is a variable resistor in which the wiper 7 is rotatably attached to the resistor board 2 by bending the wiper 7 into the resistor board 2.

By the way, in the variable resistor as mentioned above,
Conventionally, the central part of the base of the two terminals 4 is connected to the resistor board 2.
A stopper 4a on the resistance board 2 side is formed on which a stopper piece 7a that is cut upward and protrudes from the periphery of the wiper 7 in the radial direction rests against it.

However, as described above, if a part of the two terminals 4 is cut up to form the stopper 4a, the two
The terminal 4 must be at least longer than the length _h1 of the stopper 4a, and when a variable resistor as shown in Fig. 1 is mounted on the printed circuit board 9, the mounting height
There was a drawback that h ₀ (h ₀ > h ₁ ) was high. moreover,
There is a drawback that the size is large due to the rotation radius of the fan-shaped stopper piece 7a of the wiper 7 and the stopper 4a of the two-terminal cut-and-raised portion.

Purpose of the invention The present invention was made in order to eliminate the above-mentioned drawbacks, and its purpose is to provide a variable resistor in which a wiper is rotatably attached to a resistor board, in which the wiper is drawn toward the resistor board by drawing, etc. A part of the terminal is formed by forming a protruding part, and by cutting the side wall of the protruding part and placing the stopper piece protruding inside the peripheral edge of the wiper against the stopper protruding from the surface of the resistor board. Instead of cutting and raising the stopper on the outer periphery of the resistor board, a stopper is protruded near the circular hole of the resistor board, thereby reducing the mounting height and size of the variable resistor.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

In FIGS. 3 and 4, a resistive substrate 11 has a substantially arc-shaped resistive film 12 formed on its surface, and has a circular hole 13 at a position where the distance to the resistive film 12 is approximately constant. The structure is the first
It is the same as the resistor substrate 2 shown in FIGS.

Conductive films 14, 14 are provided at both ends of the resistive film 12.
1 terminal 15 and 3 terminal 16, which penetrate through the resistive substrate 11 substantially perpendicularly, are soldered to these conductive films 14, 14 with solder 17, respectively.

On the back surface of the resistance board 11, a terminal plate 19 is provided which sandwiches the resistance board 11 together with the wiper 18 and rotatably attaches the wiper 18 to the resistance board 11.
are placed.

The terminal plate 19 is formed by punching out a metal plate such as brass, and includes a wiper mounting hole 20 having a diameter slightly smaller than the circular hole 13 of the resistance board 11, and a wiper mounting hole 20 for the wiper 18.
Two terminals 21 that are electrically connected to each other and a stopper 22 of the wiper 18 are formed.

The outer periphery of the wiper mounting hole 20 of the terminal board 19 is drawn so as to protrude into the circular hole 13 of the resistance board 11, while the stopper 22 is formed by a cut provided on the outer periphery of the circular hole of the resistance board 11. Notch groove 2
3, and its tip portion protrudes from the surface of the resistor board 11.

On the other hand, the wiper 18 rotatably attached to the resistance board 11 by the terminal plate 19 is made of a metal material having spring properties such as nickel silver.

The wiper 18 has a shaft portion 24 that projects toward the circular hole 13 of the resistance board 11 and has a tapered side wall 23, and has a notch formed by cutting the protruding surface of the shaft portion 24. Piece 25, 25,...
In the circular hole 13 of the resistance board 11, the terminal plate 19 is inserted.
The wiper 18 is fitted into the wiper mounting hole 20 and bent onto the terminal plate 19, and the wiper 18 is attached to the cut and raised piece 2.
5, 25, . . . are rotatably secured to the peripheral edge of the wiper mounting hole 20 of the terminal board 19.

The slit-shaped holes 26 formed after the cut and raised pieces 25, 25, . . . are so-called driver holes into which the blade of a driver (not shown) for rotating the wiper 18 is inserted. Become.

As shown in FIG. 5, the wiper 18 also has a stopper piece on the wiper 18 side that is formed by cutting up the side wall 23 of the shaft portion 24 and protruding on both sides of a contact point 27 provided on the peripheral edge of the wiper 18. 28, 28 are made to protrude. These stopper pieces 28 , 28 are abutted against the stopper pieces 22 on the terminal plate 19 side that protrude from the surface of the resistance board 11 , and the wiper 18 is arranged such that its contacts 27 stop at both ends of the resistance film 12 .
Rotation angle is regulated.

If the variable resistor has the above configuration, the stopper pieces 28, 28 of the wiper 18 will come into contact with the stopper 22 provided on the terminal board 19 on the front side of the resistance board 11, and the variable resistor shown in FIG. It is no longer necessary to provide the cut and raised pieces 4a on the two terminals 4.
Therefore, in the variable resistors shown in FIGS. 3 and 4, the mounting heights on the printed circuit board are as shown in FIG.
By reducing the value of the height h ₁ of the wide portion of each base of 1, it can be made very low.

Incidentally, in a conventional variable resistor, the height from the printed circuit board 9 is about 6 mm, but in the variable resistors shown in FIGS. 2 and 3, it is about 3 mm.

In the present invention, the stopper piece 2 of the wiper 18
8 and 28 are located inside the periphery of the wiper 18, and the stopper pieces 28 and 28 do not protrude from the periphery of the wiper 18, so that the diameter of the wiper 18 as a whole is reduced and the variable resistor is also made smaller. .

In the above embodiment, the wiper 18 has a shaft portion 24 having a protruding portion that protrudes toward the resistance board 2, as in the wiper 7 shown in FIG. 1, instead of having the tapered side wall 23. It is also possible to use one having a part.

Further, the stopper 22 on the resistance board 11 side may be directly fixed to the resistance board 11.

Effects of the Invention As is clear from the above detailed description, the present invention provides a variable resistor with a wiper stopper piece inside the periphery of the wiper, and instead of cutting and raising a part of the terminal, the resistor board Since a stopper is provided protruding from the terminal so that the stopper piece of the wiper can rest against it, there is no need to increase the length of the terminal by cutting and raising the terminal, and the mounting height of the variable resistor to the printed circuit board can be lowered. Moreover, the diameter of the wiper can be reduced, and the size of the variable resistor can be reduced.

[Brief explanation of the drawing]

1 and 2 are a vertical cross-sectional view and a plan view, respectively, of a conventional variable resistor, FIG. 3 is a vertical cross-sectional view of an embodiment of a variable resistor according to the present invention, and FIG. 4 is a vertical cross-sectional view of a conventional variable resistor. FIG. 5 is a plan view of the variable resistor, and FIG. 5 is a side view of the variable resistor of FIG. 4...2 terminal, 4a...stopper, 11...resistance board, 12...resistance film, 13...circular hole, 18...
... Wiper, 19 ... Terminal board, 20 ... Wiper mounting hole, 21 ... 2 terminals, 22 ... Stopper, 23 ...
... Side wall, 24 ... Shaft, 25 ... Cut and raised piece, 29
...opening edge.

Claims (1)

[Scope of utility model registration request] A resistive substrate having a substantially arc-shaped resistive film formed on its surface has a concentric circular hole inside the circular arc of the resistive film, and a wiper mounting hole having a smaller diameter than the circular hole. Place the terminal board on the back side of the resistor board by aligning the wiper mounting hole of the terminal board with the two conductive terminals with the circular hole of the resistor board, and insert the cut and raised piece provided on the wiper into the resistor board. A variable resistor is formed by inserting the wiper into the wiper mounting hole of the terminal board through the circular hole, bending it onto the terminal board, and rotatably attaching the wiper to the resistor board, which is formed on the peripheral edge of the wiper. A region including the cut-and-raised piece on the inside of the contact that slides on the resistive film is formed to protrude toward the resistor substrate, and a side wall of the protruding portion is cut and raised to form a protrusion on the wiper. A variable resistor characterized in that a stopper piece is formed that protrudes inward from a peripheral edge portion, and the stopper piece is brought into contact with a stopper on the resistor board side that is provided protruding from the surface of the resistor board.