电机的电接触及表面膜研究

Study on the electric contact and surface film of electric machines

文章综述了电机上电刷的电接触种类、机理及影响因素 ,讨论了在滑动接触表面上形成的表面膜对电刷的导电性、耐磨性的影响 ,指出均匀、适度、稳定的表面膜是保证电机正常运行的条件之一。研究了碳纤维 -铜 -石墨复合材料电刷在电磨损过程中接触电压降的变化情况 ,证明了碳纤维 -铜 -石墨复合材料电刷在满足接触电阻为非线性要求上的优越性 。

The kinds, mechanism and influence factors of electric contact are reviewed. The effects of surface film on electric conductivity and antiwear property of brush have been studied,and it is found that the film makes the contact drop steady and improves commutation ability of brush. Under electrical wear condition, the contact drop and wearing surface of CF Cu G composite brush have been studied,and it is proved that the total contact drop per brush is not linear with current density.