JPS58107445A - Material for sliding contact - Google Patents

Abstract

PURPOSE:To obtain the sliding contact material having the libricativity of an alloy enhanced, abrasion resistance improved and contact resistivity stabilized at a low value, by adding limited amounts of specified elements such as Sb, Cd, Mo and Zn to a specified Ag-Sn alloy. CONSTITUTION:The sliding contact material prepared by adding 1-10wt% Sn, 0.1-3%, in total, one or more, of W, Ce, Sb, Cd, Mo, Se, As, Zn, Ca and Mg, and optionally 0.01-0.5% the group-Fe to Ag. In this contact material, the oxidies of the added elements formed during sliding motion act as a lubricant to improve the wear resistance of the Ag-Sn alloy. By the addition of the group- Fe, crystal grains are minimized, and the wear resistance is further improved. When a contact piece for the commutator of a small-sized motor is made using said material, the effect to reduce the dispersion of the rotation number of the commutator, etc. are obtained.

Description

[Detailed description of the invention] The present invention relates to improvements in sliding contact materials.

A with excellent sulfidation resistance as one of the conventional sliding 96 materials
Ag-8n alloy has been used, but since Ag-8n alloy has low lubricity and poor wear resistance, contact pieces around the commutator of small motors are manufactured and used with Ag-8n alloy. In such cases, abrasion powder is generated due to contact with the brush welder, causing noise.

The present invention has been made to eliminate such drawbacks.
, it is an object of the present invention to provide a pushing contact material which improves the lubricity of Ag-8n alloy, improves wear resistance, and has low and stable contact resistance.

One of the push contact materials of the present invention contains 8n1 to 1 in Ag.
0 weight - and W, Ce, Sb, Cd, Mo.

Se, As, Zn, Ca, and Mg are added in a total amount of 0.1 to 3% by weight.

Another sliding contact material of the present invention is KSn in Ag.
l ~ 10 wt- and W, Ce, 8 b, C
A total of 0.1 to 3% by weight of at least one of dMo, 8e, As, Zn, Cm, and Mg, and 0.0% of Fe group.
It is made by adding 1 to 0.5 weight.

In the sliding contact material of the present invention, 1 to 1
The reason why 8N of 0 weight is added is to improve the sulfidation resistance of Ag, and if it is less than 1 weight, the effect will not appear.
If it exceeds 10% by weight, a large amount of oxides will be produced, and the contact resistance will be high and unstable. Nine W, Ce
, 8b, Cd, Mo.

The reason why at least one of Ss, As, Zn, Ca, and Mg is added in a total amount of 0.1 to 3% by weight is that the oxides of the above elements generated during sliding are soft and act as a lubricant, improving wear resistance. This is to improve A g if it is less than 0.1 weight.
It is not possible to improve the thermal properties of Sn, the wear resistance is not improved, and the number of precipitated particles of the eutectic with Ag is large and large, and the amount of oxide generated by these particles is large. This is because the contact resistance is high and the instability is improved.If the weight is less than 0.01 weight, the crystal grains cannot be refined, and if the o, s, fit is more than 0.01 weight, the crystal grains cannot be refined, and if the weight exceeds o, s, fit, no alloying occurs, and large lumps are formed alone in Ag. The contact resistance is high, the variation is large, and the contact resistance is unstable.

Next, a contact piece for a commutator of a small motor made of a nine-point sliding contact material according to the present invention and a conventional sliding contact material will be described.

Using the sliding contact material according to the embodiment of the present invention and the conventional sliding contact material having the compositions shown in the right column of the table below, the diameter of the small motor is 6 mm and the length is -Ag-Cu as shown in the drawing. A rotation test of the commutator 1 was carried out under the test conditions described below by slidingly contacting brush contacts 3 having three brush wires 2 each having a diameter of 0.2511J and a length of 10 mm so as to face each other. The wear amount of the contact piece 1a and the variation in the rotation speed of the commutator 1 were measured, and the results shown in the right column of Table O below were obtained.

Test conditions Voltage = 12V 11 fit, : DC56mA Commutator rotation speed '2800rpm Commutator rotation time: 5
00 hour brush contact contact crab 5F/3 wear 11Fi 3-6μ, whereas the amount of wear of the m4 piece in the example was 2-3μ, which was significantly reduced, indicating excellent wear resistance. 6 In addition, the variation in the rotational speed of the commutator moving around the contact piece in the conventional example was 8 to 11, while the variation in the rotational speed of the commutator with the contact piece in the example was 3 to 4.5. It can be seen that there is a significant decrease in -.

As detailed above, since the sliding W single-point material of the present invention has high hardness and excellent wear resistance, the contact piece of the commutator of a small motor made using this material is in sliding contact with the brush contact piece. There is no generation of abrasion powder during operation, so there is no noise generation, and the contact resistance is low and stable, so it has excellent effects such as greatly reducing the fluctuation of the rotation speed of the commutator of small motors. There is.

[Brief explanation of the drawing]

The figure shows the commutator and brush Ii1 of the small motor. It is a perspective view which shows the contact state with a door. l...Commutator, 1a...Contact piece, 2.
...Brush wire, 3...Brush contact. Applicant Tanaka Kikinzoku Kogyo Co., Ltd.

Claims (1)

[Claims] 1) In Ag, 8n 1 to 10 weight- and W, Ce8
A sliding contact material containing a total of 0.1 to 3% by weight of at least one of Cd, Mo, 8e, As, Zn, and CmMg. 2) Ks8nl'-10wt- in Ag and W, Ce8
At least one of b, Cd, Mo, 8e, As, Zn, CaMg in total of 0°1-3% by weight and Fe group 0.01-3% by weight.
Sliding contact material made by adding 0.5 weight'ts.