JPS616232A - Sliding contact material - Google Patents

Abstract

PURPOSE:To obtain the titled material having low and stable contact resistance by adding prescribed perdentages of Cu, Cd, In and Sn to Ag so as to control the stickinessof an Ag-Cd alloy and to improve the wear resistance. CONSTITUTION:A sliding contact material is obtd. by adding 3-12wt% Cu, 0.5-5wt% Cd and 0.5-10wt% In and Sn to Ag. In the material, 0.01-0.5wt% Fe group element may be substituted for part of said added elements. Since the sliding contact material is hardly stuck and has superior wear resistance, when the contact chips 1a of a commutator 1 for a small-sized motor are made of the sliding contact material, the contact chips 1a produce very little dust due to wear during sliding along bruch contacts 3. No noise is generated and a beneficial effect such as low and stable contact resistance is shown.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to improvements in sliding contact materials.

(Prior art and problems) Ag-Cd alloy has conventionally been used as one of the sliding contact materials, but Ag-Cd alloy adheres during sliding and does not have sufficient wear resistance. When a Cd alloy is used as a contact piece for the outer periphery of a commutator of a small motor, abrasion powder is produced by sliding with the brush contact, causing noise.

(Object of the invention) The present invention has been made to eliminate such drawbacks,
It is an object of the present invention to provide a sliding contact material which suppresses the adhesion of Ag-Cd alloy, improves wear resistance, and has low and stable contact resistance.

(Structure of the Invention) The sliding contact material of the present invention contains 3 to 12% by weight of Cu, 0.5 to 5% by weight of CD, and 0.5% of 1n and Sn in Ag.
It is made up of a 5-10% heavy view device.

Further, some of the above-mentioned additive elements of the sliding contact material of the present invention are added to 0.
Fe group element (Fe.

Ni, Co) may be substituted.

In the sliding contact material of the present invention, 0.5
~5% weight Cd in addition to adding 3~12wt% C
The reason why u is added is to increase the hardness of the Ag-Cd alloy and improve its wear resistance.If it is less than 3% by weight, this effect will not appear, and if it exceeds 12% by weight, a large amount of oxides will be produced. This results in high contact resistance and instability. Furthermore, In
The reason why 0.5 to 10% by weight of Sn is added is that the oxides of the above elements generated during sliding act as lI lubricants and improve wear resistance. Adhesion cannot be suppressed and abrasion resistance cannot be improved, and if it exceeds 10% and 4%, a large amount of oxide is generated, resulting in high contact resistance and instability. 2.Furthermore, a part of the above-mentioned additional elements is added in the range of 0.01 to 0.5 wt.
When substituted with Fe, Ni, Co), the crystal grains can be made finer and the wear resistance can be further improved.If the substitution is less than 0.01% by weight, the grains cannot be made finer, and if the substitution is less than 0.5% by weight, the grains cannot be made finer. If it exceeds the range, alloying will not occur, and it will precipitate as a single large lump in Ag, resulting in high contact resistance and large variations, resulting in instability.

(Example and Conventional Example) Using the sliding contact material according to the embodiment of the present invention and the sliding contact material of the conventional example having the compositions shown in the right column of the table below, a small motor with a diameter of 12 mm, as shown in the drawings, was used. Commutator l with length 811
A contact piece 1a having a thickness of 211 is formed on the outer periphery of the contact piece 1a, and a Pd-Ag-Cu-Pt-
A brush wire 2 made of Au-Zn with a diameter of 0.7 mm and a length of 81 layers is brought into sliding contact so as to face each other, and a commutator 1 A rotation test was conducted, and the wear amount and contact resistance of the contact piece 1a were measured, and the results shown in the right column of the table below were obtained.

Test conditions Voltage: l') C12V Current: 0.6A Commutator rotation speed: 1000rpm Commutator rotation time Near time Brush contact contact crab 100g (Left below blank) [I)] 1? ; As is clear from the table 1, the connection 13. of the conventional example. It can be seen that the amount of wear on the contact piece of the example is significantly reduced compared to the amount of wear on the contact piece of the example, indicating that the contact piece of the conventional example has a lower wear resistance. In contrast, it can be seen that the contact resistance of the commutator 11 having the contact piece of the example is low and stable.

(Effects of the Invention) As detailed above, the sliding contact material of the present invention is resistant to adhesion and has excellent wear resistance. Extremely little wear powder is produced during operation, so there is no noise, and the contact resistance is low (stable), among other excellent effects.

[Brief explanation of drawings]

The figure is a perspective view showing the state of contact between the commutator and brush contacts of a small motor. ■--Commutator, 1a--Contact piece, 2-Brush wire (A, 3
Brush contact.

Claims (1)

[Claims] 1) 3 to 12% by weight of Cu and 0.5% of Cd in Ag
~5% by weight and 0.5 to 10% by weight of In and Sn. 2) The sliding contact material according to claim 1, wherein a part of the additive element is substituted with an Fe group element in a range of 0.01 to 0.5% by weight.