JPS6134143A - 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, In, Te, Ti, Li and Mg 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% In and 0.5-5wt% at least one among Te, Ti, Li and Mg 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.

(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 operation and does not have sufficient wear resistance. When a contact piece for the outer periphery of a commutator of a small motor is made of alloy and used, abrasion powder is generated due to the sliding action with the brush contact, which causes noise generation.

(Object of the invention) The present invention has been made to eliminate such drawbacks,
The present invention aims to provide a sliding contact material that suppresses the adhesion of Ag7Cd 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, 0.1 to 5% by weight of Cd, 1 to 7% by weight of In, Te, Ti, Li, At least one type of Mg from 0.5 to
It is made by adding 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, Go) 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 it is less than 3% by weight, the effect will not appear, and if it exceeds 12% by weight, 5% by weight will cause the formation of oxides. As the amount increases, the contact resistance becomes high and unstable. Also 1
The reason why ~7% by weight of In is added 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, The amount of oxide produced increases, resulting in high contact resistance and instability. Further, the addition of 0.5 to 5% by weight of at least one of Te, Ti, Li, and Mg is because the oxides of the elements generated during the rubbing operation are /Ii! This is to act as a lubricant and improve wear resistance, and if less than 0.5% by weight Ag
The adhesion of the -Cd alloy cannot be suppressed and the wear resistance is not improved, and if it exceeds 5% by weight, a large amount of oxides are generated, resulting in high contact resistance and instability. Furthermore, some of the above-mentioned additive elements are added to F in a range of 0.01 to 0.5% by weight.
When substituted with e-group elements (FeNi, Co), the 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 form an alloy, and will precipitate as a single large lump in Ag, resulting in high contact resistance and instability with large variations. It is.

(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 composition shown in the right column of the table below, a small motor with a diameter of 12N and a length as shown in the drawings was used. A contact piece 1a with a thickness of 2 fl is formed on the outer periphery of the commutator 1 of 8II11, and a contact piece 1a with a diameter of 0.7 fl and a length of 8 cranes made of Au-Ag-Cu-pt is formed above and below the outer peripheral surface of the contact piece 1a. Book brush wire 2
A rotation test was conducted on the commutator 1 under the test conditions described below, with the brush contacts 3 facing each other in sliding contact, and the wear amount and contact resistance of the contact piece 1a were measured. The results shown in the column were obtained.

Test conditions Voltage: DC12V Current: 0.6A Commutator rotation speed: 1000rpm Commutator rotation time = 7 hours Contact crab of brush contact 100g As is clear from the table above, the wear of the contact piece of the conventional example It can be seen that the amount of wear of the contact piece of the example is significantly reduced compared to the amount of wear, 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 a state of contact between a commutator and a brush contact of a small mortar. -Commutator, l a---Contact piece, 2~-Brush wire, 3
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, In 1 to 7% by weight, Te, Ti, Li,
A sliding contact material containing 0.5 to 5% by weight of at least one type of Mg. 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.