JPH05291009A - Variable resistor - Google Patents

Abstract

PURPOSE:To provide a thin variable resistor that contributes to reduce the number of component parts needed which is mainly used for sound volume adjustment of a stereo amplifier and the like. CONSTITUTION:A resistor, on which a resistance path and first and second conductive parts provided on both ends of the resistance path are concentrically arranged, is provided on both surfaces of a resistance substrate 15, and by fixing brushes 14a to 14c, which perform an additional function as an external terminal, in such a manner that the resistance substrate 15 is pinched, a space- saving variable resistor, having reduced number of component parts, can be accomplished.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable resistor mainly used for volume control of a stereo amplifier or the like.

[0002]

2. Description of the Related Art A conventional technique will be described with reference to FIGS.

As shown in FIG. 1, an operating shaft 1 is rotatably held by a bearing 2, and a brush mounting plate 3 to which a brush 4 is slidably contacted with a resistor substrate 5 is fixed by a speed nut 7 or the like. There is.

A case 8 holds the resistor substrate 5 and is fixed to the bearing 2. This resistor substrate 5
Is arranged concentrically with a resistance path 5a having conductive parts 5b and 5c at both ends thereof, the brush 4 is slidably contacting the resistance path 5a and the conductive part 10, and the outer terminals 6a, 6b and 6c are respectively conductive. It is fixed to the portions 5b, 10, 5c.

Next, the operation of the conventional variable resistor will be described. As the operating shaft 1 rotates, the brush 4 slides on the resistance substrate 5 via the brush mounting plate 3, and the position of the brush 4 changes depending on the position of the brush 4. The input signal applied to the external terminals 6a and 6c.
It can be taken out as an output signal divided between a and 6b.

[0006]

However, the above-mentioned conventional variable resistor has a long depth dimension, and the heat sink cannot be sufficiently long on the set side especially in the case of the four-strip structure, and the number of parts is large, and cost reduction is difficult. There was a certain problem.

[0007]

According to the present invention, there is provided a concentric resistance path, a first conductive path connected to one end of the resistance path, and a second conductive path connected to the other end of the resistance path. A resistor substrate having resistors formed of conductive paths on both sides, an operation shaft on which the resistor substrate is rotatably mounted, and a first conductive path and a resistance path of each of the resistors provided on both sides. A variable resistor is configured with each of the brushes for sliding out of the second conductive path, which are for external extraction.

[0008]

As described above, by providing the resistors on both sides of the resistor substrate, it is possible to make the device thinner and reduce the number of parts.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a variable resistor according to the present invention is shown in FIGS.
Will be explained.

As shown in the figure, 11 is an operating shaft, which is rotatably held by a bearing 12, a resistor substrate 15 is attached via a mounting plate 13, and is fixed by a speed nut 17. Reference numeral 14 (14a to 14c) is a brush integrated with an external terminal for leading out to the outside, which is fixed to the case 16 and comes into sliding contact with the resistor substrate 15 as the resistor substrate 15 rotates. The case 16 is fixed to the bearing and protects the resistor substrate 15 and the brush 14.

The resistor substrate 15 is formed with resistors having concentric circular surfaces on both sides of which a first conductive path 18a is connected to one end of the resistive path 15a and a second conductive path 18b is connected to the other end. The brush 14 is attached to the case 16 such that the resistor substrate 15 is symmetrically sandwiched from both sides.

Next, the operation of the variable resistor of the above embodiment will be described. When the operating shaft 11 is rotated, the resistor substrate 15 is rotated through the mounting plate, and the brushes 14a-1.
4c is a resistance path 15a and a first conductive path 18a,
The brushes 14a to 14 are slidably contacted on the second conductive path 18b.
The input signal applied to 14b and 14c according to the position of c is taken out as a signal divided between the brushes 14a and 14b.

As described above, the resistors are formed on both surfaces of the resistor substrate to save space and reduce the number of parts.

FIG. 3 shows another embodiment of the resistor substrate of the variable resistor according to the present invention. According to FIG. 3, 20 is a resistor substrate, and 21 are concentric circles at both ends. The formed first conductive path 22 and the second formed on the inner circumference
Is a resistance path in which electrodes 21a and 21b are formed at both ends formed on the resistor substrate 20 connected to the conductive path 23 of FIG.

Reference numeral 23a denotes a first end of a sliding contact portion which is electrically separated by a slit 25 from a sliding contact portion 23b of a second conductive path 23 with which a brush portion of an external terminal 24c, which will be described later, slides. The end is connected to the sliding contact portion 23b via the resistance portion 26, and the second conductive path 23 is formed in a loop shape via the slit 25. 24a, 24b, and 24c each have a resistance path 21, a first conductive path 22 on the outer periphery, and a sliding contact portion 23b and a first end 23a of the sliding contact portion on the second conductive path 23 on the inner periphery, and a resistance portion 26. , An outer terminal having a brush portion slidingly contacting the slit 25. In the variable resistor, the outer terminals 24a to 24c are attached to a case (not shown), the resistor substrate 20 is rotated, and the outer terminals 24b and 24c are rotated.
By applying an input signal to, the output signal can be taken out as a voltage divided between the outer terminals 24a and 24b according to the position of the resistance path 21.

The slit 25 is slanted with respect to the brush portion so that the outer terminal 24c is not opened.
Be sure that either contact is in contact.

Next, the operation will be described. When the resistor substrate 20 rotates and reaches the maximum attenuation direction (position A in FIG. 1), the brush portion of the outer terminal 24c exceeds the slit 25. At this time, the resistance value between the outer terminals 24b and 24c is in a form in which the resistance value of the resistance portion 26 is added to the resistance value of the resistance path 21, and the maximum attenuation is improved accordingly.

For example, the resistance value of the resistance path 21 is 10 KΩ,
The resistance between the outer terminals 24a and 24b at the time of maximum attenuation is AΩ, and there is no slit 25, and instead of the resistance portion 26, the sliding contact portion 2 is provided.
If 3b is extended, it becomes equivalent to the conventional example, and if the maximum attenuation amount at this time is -100 dB, the following (Equation 1) is simply obtained.

[0019]

[Equation 1]

Next, a slit 25 is provided as in the present invention,
If the resistance value of the resistance path 21 is 10 KΩ and the resistance value of the resistance portion 26 is 90 KΩ, the outer terminals 24b and 24c are at the maximum attenuation.
The resistance value between them is 100 KΩ, and the maximum attenuation amount x is simply the following (Equation 2).

[0021]

[Equation 2]

120 dB and 20 as in the above (Equation 2)
The maximum dB attenuation is improved. Although the above description has been made on the rotary type variable resistor, the same configuration can be applied to the slide type variable resistor.

As described above, according to another embodiment of the variable resistor of the present invention shown in FIG. 3, a slit is provided between the sliding contact portion and the end of the sliding contact portion of the second conductive path, and this sliding contact portion is provided. Since the resistance portion is continuously provided at the end and the second conductive path is formed into a loop shape through the slit, the resistance value of the resistance path and the resistance portion is only at the maximum damping when the brush sliding jointly is located at the end. Can be added to improve the maximum attenuation.

In the embodiment of FIG. 3, the variable resistor is made thinner and the maximum attenuation is improved. However, when only the maximum attenuation is improved, the above-mentioned FIG. This can be achieved by adopting only the structure of the resistance substrate of.

[0025]

As described above, according to the present invention, the concentric resistance path, the first conductive path connected to one end of the resistance path, and the second conductive path connected to the other end of the resistance path. A resistor substrate having resistors formed of conductive paths on both sides, an operation shaft on which the resistor substrate is rotatably mounted, and a first conductive path and a resistance path of each of the resistors provided on both sides. Since the variable resistor is configured with the respective brushes for sliding out of the second conductive path for external extraction, the resistors are provided on both sides of the resistor substrate,
This saves space and reduces the number of parts.

[Brief description of drawings]

FIG. 1 is a side sectional view of an embodiment of a variable resistor of the present invention.

FIG. 2 is a top view for explaining the relationship between the resistor substrate and the brush, which is the main part of the same.

FIG. 3 is a top view illustrating a relationship between a resistor substrate and a brush, which is a main part of another embodiment.

FIG. 4 is a side sectional view of a conventional variable resistor.

FIG. 5 is a top view for explaining the relationship between the resistor substrate and the brush, which is the main part of the same.

[Explanation of symbols]

 11 Operation Axis 15a Resistance Path 18a First Conduction Path 18b Second Conduction Path 14a to 14c Brush 20 Resistor Substrate 21 Resistor 22 First Conduction Path 23 Second Conduction Path 23a Sliding Contact First End 23b Sliding Contact 24a to 24c Outer terminal integrated with brush 25 Slit 26 Resistor

Claims (3)

[Claims] 1. A double-sided resistor having a concentric resistance path, a first conductive path connected to one end of the resistance path, and a second conductive path connected to the other end of the resistance path. A resistor substrate, an operation shaft on which the resistor substrate is rotatably mounted, and a first conductive path, a resistance path, and a second conductive path of the resistors provided on both surfaces, which are in sliding contact with each other. Variable resistor consisting of each brush for derivation. 2. A resistance path having electrodes at least at both ends, a first conductive path connected to one end of this resistance path, and a slide contact portion and a resistance portion connected to the other end of this resistance path. Brushes that slide together on the sliding contact portions of the second conductive path formed in a loop, the first conductive path, the resistance path, and the second conductive path, and slide on the resistance path. When the brush to be positioned is located at the electrode at one end of the resistance path, the sliding contact portion is provided at the sliding contact portion of the second conductive path where the brush sliding along the second conductive path is located, with a slit provided therebetween. A variable resistor configured such that a first end portion and the resistance portion are provided between the other end of the sliding contact portion first end portion and the sliding contact portion. 3. The slit between the sliding contact portion and the first end of the sliding contact portion is provided obliquely to the sliding direction of the brush, and
The variable resistor according to claim 2, wherein the brush is provided with a plurality of contacts.