JPS6134144A - Sliding contact material - Google Patents

Abstract

PURPOSE:To obtain a sliding contact material hardly causing agglutination and having superior wear resistance by adding specified percentages of Cu, Cd, Sb, Si, Bi, Ge and Ga to Ag. CONSTITUTION:The sliding contact material having low and stable contact resistance as well as reduced agglutination and improved wear resistance is obtd. by adding 3-12wt% Cu, 0.1-5wt% Cd, 1-7wt% Sb and 0.5-5wt% at least one among Si, Bi, Ge and Ga to Ag. When a part of the added elements, is substituted with 0.01-0.5wt% Fe group element such as Fe, Ni or Co crystal grains are made fine and the wear resistance can be improved further.

Description

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

(Conventional technology and problems) Ag-Cd alloy has traditionally been used as one of the sliding contact materials, but Ag-Cd alloy adheres during sliding operation 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 due to the sliding action with the brush contact, causing noise.

(Object of the invention) The present invention has been made to eliminate such drawbacks,
The object of the present invention is to provide a sliding contact material that suppresses the adhesion of Ag-Cd alloys, 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, 0.1 to 5% by weight of Cd, 1 to 7% by weight of Sb, and Si, Bi+ Ge, Ga. 0.
It is made by adding 5 to 5% by weight.

Further, some of the additive elements of the sliding contact material of the present invention are 0.
Fe group element (Fe.

Ni, Co) may be substituted.

In the sliding contact material of the present invention, 0.1
3-12 wt% C in addition to adding ~5 wt% Cd
The purpose of adding u is to increase the hardness of the Ag-Cd alloy and improve its wear resistance.If the amount is less than 3M%, 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. Also 1-7
The purpose of adding MN% of Sb is to increase the adhesion resistance of the Ag-Cd alloy and improve its wear resistance.If it is less than 1% by weight, the effect will not appear, and if it exceeds 7% by weight, it will cause oxides. The amount of contact produced increases, resulting in high contact resistance and instability. Furthermore, the reason why at least one of Si, Bi, Ge, and Ga is added in an amount of 0.5 to 5% by weight is that oxides of the above elements generated during the sliding action act as a lubricant and improve wear resistance. If it is less than 0.5% by weight, it will not be possible to suppress the adhesion of the Ag-Cd alloy and the wear resistance will not improve, and if it exceeds 5% by weight, the amount of oxides generated will be large, resulting in high contact resistance and failure. It is stable. Furthermore, when some of the above additive elements are replaced with Fe group elements (FeNi, Co) in the range of 0.01 to 0.5% by weight, crystal grains can be made finer and wear resistance can be further improved. If it is less than 0.01% by weight, the crystal grains cannot be refined, and if it exceeds 0.5% by weight, it will not be alloyed and will precipitate as a single large lump in Ag, resulting in high contact resistance and large variations. This is unstable.

(Example and Conventional Example) Using a sliding contact material according to an embodiment of the present invention and a conventional sliding contact material having the compositions shown in the right column of the table below, a small motor with a diameter of 12fi and a length as shown in the drawings was used. A contact piece 1a with a thickness of 2N is formed on the outer periphery of the commutator 1 of the 8 cranes, and this contact piece 1
Brush contacts 3 having two brush wires 2 made of Au-Ag-Cu-pt with a diameter of 0.1 tm and a length of 81 are brought into sliding contact with each other so as to face each other on the upper and lower sides of the outer peripheral surface of a. A rotation degree test of the commutator 1 was conducted under the test conditions, and the contact piece 1a
The wear amount and contact resistance were measured, and the results shown in the right column of the table below were obtained.

Test conditions Voltage: DC12V Current 7 0.6A Commutator rotation speed: 1000rpm Commutator rotation time Near time Brush contact contact crab 100g As is clear from the table above, the amount of wear on the conventional contact piece It can be seen that the amount of wear of the contact piece of the example is significantly reduced compared to that of the example, indicating that the contact piece of the example has excellent wear resistance. Furthermore, it can be seen that the contact resistance of the commutator having the contact pieces of the example is lower and more stable than the contact resistance of the commutator having the contact pieces of the conventional example.

(Effects of the Invention) As detailed above, the sliding contact material of the present invention is resistant to adhesion and has excellent wear resistance, so the contact piece of the commutator of a small motor made using this material has sliding action with the brush contact. There are excellent effects such as extremely little generation of abrasion powder, therefore no noise, and low and stable contact resistance.

[Brief explanation of the drawing]

The figure is a perspective view showing the state of contact between the commutator and brush contacts of a small motor. ■---Commutator, la-one contact piece, 2--brush wire, 3--one brush contact.

Claims (1)

[Claims] 1) 3 to 12% by weight of Cu and 0.1 to 0.1 to 12% by weight of Cd in Ag
5% by weight and 1 to 7% by weight of Sb, Si, Bi, Ge,
A sliding contact material containing 0.5 to 5% by weight of at least one type of Ga. 2) The sliding contact material according to claim 1, wherein a part of the additional element is substituted with an Fe group element in a range of 0.01 to 0.5% by weight.