JPH0368499B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a brush material for making a comb-like sliding brush that is attached to a spring base and used as a sliding contact.

Conventionally, this seed brush material includes Cu-Be, Cu-
Cu-based alloys such as Ni, Cu-Sn, Cu-Ni-Zn, Cu-Ti, and phosphor bronze have been used;
When a comb-shaped sliding brush made of a base alloy is attached to a spring base material and used as a sliding contact in contact with a commutator, when the sliding contact slides due to the rotation of the commutator,
The contact portion of the comb-shaped sliding brush is subject to significant wear due to electrical and mechanical erosion, resulting in a short service life. Further, noise is generated due to wear particles.

The present invention has been made in order to solve such problems, and provides a brush material for sliding contacts that can make a stable comb-shaped sliding brush that has extremely little wear due to electrical and mechanical erosion. That is.

The brush material for sliding contacts of the present invention has a two-layer coating applied to the surface of a Cu-based alloy, and the first layer is made of Cr, Ni,
Either Ni alloy or Re has a thickness of 1 to 20 μm, and the second
The layer is characterized by being coated with either Sn or In with a thickness of 0.1 to 10 μm.

In this way, Cr is added as the first layer on the surface of the Cu-based alloy.
The reason for coating Ni, Ni alloy, or Re with a thickness of 1 to 20 μm is to impart mechanical hardness to the Cu-based alloy brush material and improve wear resistance during sliding. There is no effect if the thickness is less than 1μm, and if the thickness is less than 20μm.
This is because if it exceeds m, the spring properties will decrease and the commutator, which is the other party during sliding, will wear out more quickly. The reason for coating either Sn or In with a thickness of 0.1 to 10 μm on the surface of the first layer as the second layer is to provide lubricity to the surface of the first layer and further reduce wear, and to This is to prevent initial welding. If the thickness is less than 0.1 μm, it will not have this effect, and if the thickness exceeds 10 μm, the wear reduction effect due to lubricity will not be significantly improved. If it is 10 μm or less, initial welding can be sufficiently prevented. It is something.

Next, in order to clarify the effects of the brush material for sliding contacts of the present invention, specific examples and conventional examples thereof will be described.

Example 1 Cr plating was applied to the surface of Cu-Be to a thickness of 5 μm, and Sn plating was applied thereon to a thickness of 5 μm to obtain a brush material for a sliding contact.

Example 2 A brush material for a sliding contact was obtained by applying 10 μm of Cr plating to the surface of 30% by weight Cu-Ni and applying 2 μm of In plating thereon.

Example 3 A brush material for a sliding contact was obtained by applying Ni plating to 15 μm on the surface of 10% by weight Cu-Sn, and then applying Indium plating to 8 μm on top.

Example 4 A brush material for a sliding contact was obtained by applying Re plating to a thickness of 10 μm on the surface of 10% by weight of Cu-Ni and 2% by weight of Zn, and then applying In plating to a thickness of 4 μm thereon.

Example 5 Cr plating was applied to the surface of phosphor bronze to a thickness of 3 μm, and Sn plating was applied thereon to a thickness of 0.5 μm to obtain a brush material for a sliding contact.

Example 6 Ni plating of 5 μm was applied to the surface of Cu-Ti 3% by weight,
On top of that, Sn plating was applied to a thickness of 1 μm to obtain a brush material for a sliding contact.

Conventional Examples 1 to 6 Brush materials for sliding contacts that are made of the same base material as the brush materials for sliding contacts of the above embodiments and that do not have two layers of plating.

However, using the brush materials for sliding contacts of Examples 1 to 6 and Conventional Examples 1 to 6, comb-shaped sliding brushes were each made.
We made 100 pieces and used them as sliding contacts in contact with a commutator made of 20% by weight Cu-Zn. The sliding brushes made from the brush materials had an extremely high wear amount of 5 to 7 mg after 100 hours of continuous use, whereas the sliding brushes made from the brush materials for sliding contacts of Examples 1 to 6 had an extremely large amount of wear of 5 to 7 mg. Sliding brush is 100
The amount of wear was extremely small at 2 to 3 mg after continuous use for a long time. In addition, in the sliding brushes made from the brush materials for sliding contacts of Conventional Examples 1 to 6, there were 6 to 7 pieces that were initially welded after the start of sliding, whereas for the sliding contacts of Examples 1 to 6, There was no initial welding of the sliding brushes made from the brush material after the beginning of sliding.

The two-layer coating of the brush material for sliding contacts of the present invention may be applied not only by plating but also by sputtering, ion plating, thermal spraying, vapor deposition, or other means.

As detailed above, in the brush material for sliding contacts of the present invention, the surface of a Cu-based alloy is coated with Cr, Ni, Ni alloy, or Re, and on top of that is coated with Sn or In. Therefore, the sliding brush made using this method has excellent mechanical hardness and a surface layer with excellent lubricity, and has extremely little wear due to electrical and mechanical erosion when sliding with the commutator. It has the excellent effect of increasing the lifespan, suppressing the generation of noise due to abrasion powder, and further preventing initial welding after the start of sliding.

Claims (1)

[Claims] 1. In a brush material for sliding contacts made of a Cu-based alloy, two layers of coating are applied to the surface of the brush material,
The first layer is made of Cr, Ni, Ni alloy, or Re with a thickness of 1 to 20 μm, and the second layer is made of Sn or In with a thickness of 0.1 μm.
A brush material for sliding contacts characterized by a coating of ~10 μm.