SLIDING ELECTRIC COMPONENT

Provided is a sliding electric component that extends the service life of a slider, inhibits the occurrence of abnormal sounds during sliding, smooths the sliding of the slider, and inhibits the occurrence of abrasion powder from carbon paste. The sliding electric component comprises a first power collection part (12), a second power collection part (13), and a slider (15) for sliding on the first power collection part (12) and the second power collection part (13), wherein the a plurality of areas (12a, 13a) composed of carbon paste are formed in the sliding direction of the slider (15) in continuous fashion on the second power collection part (13) on which the slider (15) slides.

TECHNICAL FIELD

The present invention relates to a sliding electric component such as a potentiometer or switch provided with a wiper.

BACKGROUND ART

Switch circuits each configured to electrically connect or disconnect between terminals via sliding of a wiper on a power collecting portion or an insulator have been widely used. For example, Patent Literature (hereinafter, referred to as “PTL”) 1 and PTL 2 each disclose an example of the switch circuit.

PTL 1 discloses a technique that forms the insulator by cutting a power collecting portion formed on an insulating substrate. In addition, PTL 2 discloses a technique that forms the insulator by forming a comb-shaped power collecting portion on an insulating substrate.

FIG. 11is a schematic diagram of a switch circuit according to the related art. This switch circuit includes first and second terminals1and2, first and second power collecting portions3and4, and insulator5, and wiper6. First and second power collecting portions3and4are each formed of an etched metal foil or a metal part or conductive coating material such as silver.

When wiper6made of metal is positioned in contact with first and second power collecting portions3and4, the switch is in a closed state where first and second terminals1and2are in electric conduction. Meanwhile, when wiper6is positioned in contact with first power collecting portion3and insulator5, the switch is in an open state where first and second terminals1and2are not in electric conduction.

FIG. 12is a diagram illustrating the relationship between the output of the switch circuit and a sliding distance of wiper6. When wiper6is positioned on power collecting portion4, the switch is in the closed state, so that the output of the switch is 100%. When wiper6slides to the position of insulator5, the switch turns into the closed state, and the output of the switch becomes zero.

When wiper6slides on first and second power collecting portions3and4, there may be noise and/or unsmooth sliding due to friction between the metals. Moreover, the life of wiper6being slidable may be reduced. For this reason, carbon paste excellent in slidability is often applied to the entire surfaces of first and/or second power collecting portions3and4.

CITATION LIST

Patent Literature

SUMMARY OF INVENTION

Technical Problem

When the carbon paste is applied to the entire surfaces of first and/or second power collecting portions3and/or4, the applied carbon paste generates abrasion powder. The generated abrasion powder easily scatters, and when the abrasion powder scatters to insulator5, the insulation quality of insulator5may degrade.

The present invention has been made in order to solve the problem mentioned above and thus aims to provide a sliding electric component capable of extending the life of a wiper, suppressing noise during sliding, making the wiper slide smoothly, and suppressing the generation of abrasion powder from carbon paste.

Solution to Problem

The present invention can provide a sliding electric component including: a first power collecting portion; a second power collecting portion; and a wiper configured to slide on the first and the second power collecting portions, in which a plurality of regions each made of carbon paste are formed on the second power collecting portion where the wiper slides, the plurality of regions being intermittently formed in a direction in which the wiper slides.

Advantageous Effects of Invention

According to the present invention, it is made possible to extend the life of a wiper, suppress noise during sliding, make the wiper slide smoothly, and suppress the generation of abrasion powder from carbon paste.

DESCRIPTION OF EMBODIMENT

Hereinafter, a description will be given of an embodiment of the present invention with reference to the drawings.

FIG. 1is a diagram illustrating an exemplary configuration of a sliding electric component according to the embodiment of the present invention. As illustrated inFIG. 1, this sliding electric component includes first and second terminals10and11, first and second power collecting portions12and13, insulator14, and wiper15. First and second power collecting portions12and13are each formed of an etched metal foil or a metal part or conductive coating material such as silver

When wiper15made of metal is positioned in contact with first and second power collecting portions12and13, the switch is in a closed state where first and second terminals10and11are in electrical conduction. Meanwhile, when wiper15is positioned in contact with first power collecting portion12and insulator14, the switch is in an open state where first and second terminals10and11are not in electrical conduction.

Carbon paste regions12aand13ahaving conductivity are intermittently formed in a direction in which wiper15slides. Carbon paste regions12aare formed on the surface of first power collecting portion12to be in contact with wiper15while carbon paste regions13aare formed on the surface of second power collecting portion13to be in contact with wiper15.

The formation of carbon paste regions12aand13aexcellent in slidability can extend the life of slidability of wiper15twice as long as that of the related art. Moreover, it is made possible to suppress the noise that is generated when wiper15slides. Furthermore, the frictional coefficient becomes so small that wiper15slides smoothly.

Furthermore, forming carbon paste regions12aand13aintermittently can suppress the generation of abrasion powder. Thus, an increase in the contact resistance value between wiper15and first power collecting portion12or second power collecting portion13can be suppressed. Furthermore, the amount of abrasion powder that scatters to insulator14can be reduced, so that insulator14can be prevented from decreasing in insulation quality. Thus, the switch increases in reliability.

Note that, although carbon paste regions12aand13aare formed on the surfaces of both first and second power collecting portions12and13in the example ofFIG. 1, carbon paste regions12aand13amay be formed on the surface of only one of first and second power collecting portions12and13. The advantageous effects of the present application mentioned above can be obtained about in this case as well.

FIGS. 2 to 7are diagrams each illustrating a relationship between the shape of wiper15and a carbon paste formation pattern. When wiper15includes two metal brushes as illustrated inFIG. 2, a pattern is formed in which one of the metal brushes intermittently comes into contact with carbon paste regions12awhile the other brush intermittently comes in contact with carbon paste regions13awith sliding of wiper15.

When wiper15includes four metal brushes as illustrated inFIG. 3, a pattern is formed likewise in which two of the four metal brushes intermittently come in contact with carbon paste regions12awhile the other two brushes intermittently come in contact with carbon paste regions13a.In the case ofFIG. 3, two of the four metal brushes are always in contact with carbon paste regions12aand13a.For this reason, the slidability of wiper15can be kept in uniform regardless of the position of wiper15.

In addition, a dotted pattern in which circular carbon paste regions12aand13aare spread may be employed as illustrated inFIG. 4. This pattern reduces the total area of carbon paste regions12aand13a,so that it is made possible to significantly suppress the generation of abrasion powder while suppressing degradation in slidability of wiper15.

Moreover, as illustrated inFIGS. 5 to 7, carbon paste regions12aand13amay be each formed in a rhombus, trapezoid or star shape or a shape other than these shapes. In this case as well, it is made possible to significantly suppress the generation of abrasion powder while suppressing degradation in slidability of wiper15as in the case where carbon paste regions12aand13aare each formed in a circular shape.

Furthermore, although first and second power collecting portions12and13are each formed in a linear shape inFIGS. 1 to 7, these portions do not have to be formed in a linear shape. In addition, althoughFIGS. 1 to 7illustrate switch circuits, the present invention is applicable to other sliding electric components such as a potentiometer, for example.

FIG. 8is a diagram illustrating an exemplary configuration of a potentiometer with a switch. This potentiometer provided with a switch includes first and second terminals10and11, first and second power collecting portions12and13, insulator14, wiper15, third and fourth terminals20and21, resistor22, third power collecting portion23, wiper24and rotating body30, which are placed on insulating substrate31.

Wipers15and24are attached to rotating body30. Rotating body30is rotatably supported by insulating substrate31.

First and second terminals10and11, first and second power collecting portions12and13, insulating body14, wiper15, and carbon paste regions12aand13aare identical to the elements of the switch circuit described withFIGS. 1 to 7.

In the example ofFIG. 8, however, first and second power collecting portions12and13are each formed in an arc shape. Moreover, carbon paste regions12aand13aare formed intermittently in a direction in which wiper15slides. Thus, the advantageous effects described in the cases ofFIGS. 1 to 7can be obtained.

Meanwhile, third and fourth terminals20and21, resistor22, third power collecting portion23and wiper24form a potentiometer. Resistor22is formed of a carbon resistor, for example. Moreover, third power collecting portion23is formed of an etched metal foil or a metal part or conductive coating material such as silver

In addition, the resistor value between third terminal20and fourth terminal21can be changed by sliding wiper24made of metal while wiper24is in contact with both resistor22and third power collecting portion23.

Furthermore, carbon paste regions23ahaving conductivity are formed intermittently on third power collecting portion23in a direction in which wiper24slides. Thus, the same effects as those described in the cases inFIGS. 1 to 7can be obtained.

Note that, carbon paste regions12a,13aand23amay be formed from the edges of first, second and third power collecting portions12,13and23with a predetermined interval.

FIGS. 9 and 10are diagrams for describing the positions where carbon paste regions12aand13aare formed.FIGS. 9 and 10each illustrate a cross section of first and second power collecting portions12and13in a short-side direction, where carbon paste regions12aand13aare formed.

In the example ofFIG. 9, carbon paste regions12aare formed from the edge of first power collecting portion12in the short-side direction with a predetermined interval while carbon paste regions13aare formed from the edge of second power collecting portion13in the short-side direction with a predetermined interval. In this case, even when carbon paste regions12aand13aare somewhat shifted in position due to manufacturing variations, the possibility of first and second power collecting portions12and13being electrically connected with each other is low.

Meanwhile, when carbon paste regions12aand13aare formed without the interval mentioned above, first and second power collecting portions12and13may be electrically connected with each other due to manufacturing variations. For example, as illustrated inFIG. 10, carbon paste region12amay extend to carbon paste region13aand cause first power collecting portion12and second power collecting portion13to be electrically connected with each other.

Because of the concern mentioned above, carbon paste regions12aare formed from a the edge of first power collecting portion12in the short-side direction with a predetermined interval while carbon paste regions13aare formed from the edge of second power collecting portion13in the short-side direction with a predetermined interval. Thus, the insulation quality between first and second power collecting portions12and13can be ensured.

As has been described above, the sliding electric component according to the embodiment is capable of extending the life of the wiper, suppressing noise during sliding, making the wiper slide smoothly, and suppressing the generation of abrasion powder from carbon paste.

INDUSTRIAL APPLICABILITY

The sliding electric component according to the present invention is suitable for use as a sliding electric component such as a potentiometer or switch provided with a wiper.

REFERENCE SIGNS LIST

3,12First power collecting portion

4,13Second power collecting portion

12a,13a,23aCarbon paste region

23Third power collecting portion