JP2001006908A - Sliding resistor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sliding resistor excellent in electric characteristic, sliding performance and wear resistance. SOLUTION: In a sliding resistor 3, a plurality of first carbon layers 1 containing much resin component and a second carbon layer 2 containing much conductive component are collectively formed integrally. The first carbon layer 1 is formed of many particles. The second carbon layer 2 is printed and formed on the first carbon layer 1. The sliding resistor 3 is baked and formed on a substrate composed of thermosetting resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a sliding resistor having a plurality of carbon layers.

[0002]

2. Description of the Related Art Conventionally, as this kind of technique, there is a technique disclosed in, for example, Japanese Utility Model Laid-Open Publication No. 3-43766. In this conventional resistance substrate, an upper resistance layer made of the same resistor paste is provided on a lower resistance layer made of a resistor paste.

[0003]

However, in the above-described conventional resistor, when the sliding body slides for a long period of time, the carbon film is shaved and wear powder is generated. This abrasion powder causes a problem that it becomes a noise and an accurate resistance value cannot be obtained.

[0004] Further, when a carbon film containing a large amount of resin having a large amount of base components is used as a resistor, the slidability is improved, but the amount of conductive components is reduced, and an accurate resistance value cannot be obtained. is there.

[0005] An object of the present invention is to provide a sliding resistor excellent in electric characteristics, slidability and wear resistance.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and the invention of claim 1 relates to a sliding resistor in which a sliding contact piece slides. A plurality of first carbon layers each containing a large amount of a resin component, and a second carbon layer containing a large amount of a conductive component;
And a carbon layer.

According to a second aspect of the present invention, in the first aspect, the first carbon layer is formed of a large number of particles,
The second carbon layer is printed on the first carbon layer.

According to a third aspect of the present invention, in the first aspect of the invention, the sliding resistor is fired on a substrate made of a thermosetting resin.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to FIGS. In FIG. 1, 1 is a first carbon layer, 2 is a second carbon layer, 3 is a sliding resistor, and 4 is a holder.

The first carbon layer 1 is formed of a resistor such as a so-called carbon film containing a large amount of a resin component such as a phenol resin as a base component. The first carbon layer 1 has a high hardness and a high resistance. The first carbon layer 1 is, for example, in the form of small particles having a substantially circular upper surface 1a as shown in FIG.

The first carbon layer 1 may be formed of one type of carbon layer or a plurality of types of carbon layers having different components. The shape of the surface of the first carbon layer 1 is not limited to a circle, but may be a square or a polygon.

The second carbon layer 2 is a resistor for covering and fixing the first carbon layer 1 made of many particles. The second carbon layer 2 is formed of a so-called carbon film containing a large amount of a conductive component such as carbon black as a conductive component. The second carbon layer 2 has a lower hardness and a lower resistance than the first carbon layer 1. The second carbon layer 2 fixes the first carbon layer 1 and has excellent electrical characteristics and slidability. Thereby, even if it is used for a long period of time, it is excellent in abrasion resistance and electric characteristics can be maintained.

FIG. 6 is a graph showing the relationship between the amount of resin and the hardness of the carbon layer. As shown in FIG. 6, the hardness increases as the amount of resin contained in the carbon layer increases. The first
The carbon layer 1 is formed of, for example, a hard material having a resin amount of about 1.5 [%]. The second carbon layer 2 is formed of a soft material having a resin amount of about 0.5%.

FIG. 7 is a graph showing the relationship between the amount of resin for the carbon layer and the resistance value. As shown in FIG. 7, as the amount of resin contained in the carbon layer increases, the resistance value increases. The first carbon layer 1 is formed of a material having a high resistance, for example, a resin amount of about 1.5 [%]. The second carbon layer 2 is
It is formed of a resin having a low resistance of about 0.5 [%].

The sliding resistor 3 is a resistor in which the first carbon layer 1 and the second carbon layer 2 are blended and integrated. The sliding resistor 3 is formed by solidifying the surface 1a of the first carbon layer 1 and the surface 2a of the second carbon layer 2 flush. The carbon layer of the sliding resistor 3 is not limited to the first carbon layer 1 and the second carbon layer 2, but may be formed of three or more types of carbon layers.

The holding body 4 is made of a non-conductive thermosetting resin that exposes the surfaces 1a and 2a of the sliding resistor 3 flush with each other and covers the peripheral side surface and the bottom surface. The holder 4 is made of, for example, an epoxy resin-based thermosetting resin. The holder 4 is
For example, it is formed of a printed board having a circular or rectangular shape or a polar board. The shape of the holding body 4 may be an appropriate shape according to the purpose of use, and the shape is not particularly limited.

Next, the manufacturing process of the sliding resistor 3 will be described in detail with reference to FIGS. 2, 3, 4 and 5. In the first step, as shown in FIGS. 2 and 3, a large number of first carbon layers 1 having a high resin component are arranged in a desired range on the aluminum foil 5 as a first layer, screen-printed, and fired. The first carbon layer 1 has, for example, a substantially circular drum shape with a flat surface 1a as shown in FIG.

In the second step, as shown in FIGS. 4 and 5, on the first carbon layer 1 of the aluminum foil 5 formed in the first step, a film-like second carbon layer having a large amount of conductive components is formed. 2 is screen printed as a second layer, baked, and
Is molded. The periphery of the first carbon layer 1 is covered with a second carbon layer 2. Thereby, the large number of first carbon layers 1 juxtaposed in the first step are solidified by the second carbon layers 2.

In the third step, the sliding resistor 3 fired in the second step is transfer-molded by using a holder 4 made of a thermosetting resin, and the aluminum foil 5 is peeled off. The resistor 3 is completed. Since the surfaces 1a and 2a of the first carbon layer 1 and the second carbon layer 2 are formed so as to be placed on the upper surface of the aluminum foil 5, the surfaces 1a and 2a of each other are formed flush.

The shape of the sliding resistor 3 and the holding member 4 that covers the lower surface and the peripheral side surface of the sliding resistor 3 are not particularly limited, and may be any suitable shape depending on the use.

Next, another embodiment will be described in detail with reference to FIGS. 8 is a plan view schematically showing another embodiment of the present invention, FIG. 9 is a schematic enlarged sectional view of a main part, FIG. 10 is a schematic enlarged perspective view of a main part, and FIG. 11 is a line CC of FIG. FIG. 12 is an enlarged plan view showing an example of a sliding contact piece used for an automobile steering angle sensor.

The products shown in FIGS. 8 to 11 have, for example, sliding contact pieces 8 and 9 which slide on circular sliding resistors 6 and 7 along the sliding resistors 6 and 7, respectively. These are volume and sliding resistance type sensors.

The sliding resistors 6 and 7 are the same resistors as the sliding resistor 3 described above. The sliding resistors 6, 7 are
Second carbon layers 12 and 13 containing a large amount of conductive components are formed on first carbon layers 10 and 11 containing a large amount of resin components.
Is printed. The sliding resistors 6 and 7 are baked on a substrate 14 formed of a thermosetting resin.

The substrate 14 has a substantially disc shape having a through hole 15 at the center for inserting a shaft rod or the like. The sliding contact pieces 8 and 9 are, for example, a large number of metal brushes 8 having elasticity.
a and 9a are arranged in a plate shape, and slide in a circular shape in accordance with the pattern shape of the sliding resistors 6 and 7. still,
The sliding contact pieces 8, 9 may be formed by a single metal leaf spring.

Incidentally, the metal brush 8 of the sliding contact pieces 8, 9 is used.
The numbers a and 9a may be, for example, about ten as shown in FIG. 12, and the number is not particularly limited. FIG.
The width T1 of the metal brushes 8a and 9a shown in FIGS. 11 and 12 is 0.2 to 1.0 [mm]. The first carbon layers 10 and 11 are formed of grains having a width T2 of 0.2 to 05 [mm]. The first carbon layers 10 and 11 are smaller than the width T1 of the metal brushes 8a and 9a, and have a size such that one metal brush 8a and 9a contacts a plurality of first carbon layers 10 and 11. Is desirable.

The above-described substrate 14 is used, for example, for an automobile throttle sensor, a steering angle sensor, a tire angle sensor, and the like. The sliding contact pieces 8 and 9 may be linearly moved by arranging the sliding resistors 6 and 7 in a linear shape.

[0027]

Since the present invention is constructed as described above, the following effects can be obtained. The invention according to claim 1 is the sliding resistor in which the sliding contact piece is in sliding contact, wherein the sliding resistor contains a large amount of a resin component, a plurality of first carbon layers, and a large amount of a conductive component. And a second carbon layer, which provides a sliding resistor having excellent sliding properties and abrasion resistance of the first carbon layer and excellent electrical properties of the second carbon layer. Can be.

According to a second aspect of the present invention, in the first aspect of the present invention, the first carbon layer is formed into a large number of particles, and the second carbon layer is printed on the first carbon layer. Thus, the large number of particulate first carbon layers can be firmly formed by the second carbon layer, and the first carbon layer in the second carbon layer can be solidified.
It is possible to provide a sliding resistor that can obtain a desired resistance value by adjusting the density of the carbon layer.

According to a third aspect of the present invention, there is provided the sliding resistor according to the first aspect of the present invention, wherein the sliding resistor is fired on a substrate made of a thermosetting resin so that an accurate resistance value can be obtained. Can be easily installed on a board or switch plate having a desired shape.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a plan view showing a first step in the drawing showing the embodiment of the present invention.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a plan view showing a second step in the drawing showing the embodiment of the present invention.

FIG. 5 is a sectional view taken along line BB of FIG. 4;

FIG. 6 is a drawing showing an embodiment of the present invention, and is a graph showing a relationship between a resin amount and a hardness with respect to a carbon layer.

FIG. 7 is a graph showing an embodiment of the present invention and is a graph showing a relationship between a resin amount and a resistance value with respect to a carbon layer.

FIG. 8 is a plan view schematically showing another embodiment of the present invention.

FIG. 9 is a drawing showing another embodiment of the present invention, and is a schematic enlarged sectional view of a main part.

FIG. 10 is a drawing showing another embodiment of the present invention, and is a schematic enlarged perspective view of a main part.

FIG. 11 is a sectional view taken along line CC of FIG. 6;

FIG. 12 is a drawing showing another embodiment of the present invention, and is an enlarged plan view of a sliding contact piece.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st carbon layer 2 2nd carbon layer 3,6,7 Sliding resistor 4 Holder 8,9 Sliding contact piece 14 Substrate

Claims (3)

[Claims] In a sliding resistor (3, 6, 7) in which sliding contact pieces (8, 9) are in sliding contact, said sliding resistor (3, 6, 7) contains a large amount of a resin component. A sliding resistor comprising a plurality of first carbon layers (1) and a second carbon layer (2) containing a large amount of conductive components. 2. The invention according to claim 1, wherein the first carbon layer (1) is formed in a number of particles, and the second carbon layer (2) is formed on the first carbon layer (1). A sliding resistor formed by printing on a sliding resistor. 3. The sliding resistor according to claim 2, wherein the sliding resistor is fired on a substrate made of a thermosetting resin. body.