| 摘要 |
PURPOSE:To reduce the electric resistance value and thermal resistance value of a brush by mixing metal fiber in carbon powder, solidifying the mixture and forming a brush material. CONSTITUTION:Carbon powder is mixed with ultrafine fiber made of metal having small electric resistance value and thermal resistance value such as copper, silver, aluminum or their alloy, the mixture is then shaped, and solidified, thereby forming a material for a brush. Since in the thus formed material metal fiber is contacted with each other in the carbon powder to preferably transmit a current and heat, a voltage drop due to brush is small, and the temperature rise of the brush due to slidable contact of the brush with a commutator becomes less. |
