| 摘要 |
PURPOSE:To finish the surface of a commutator sliding in contact with a brush with a simple process employing a press die having a slightly roughened pressure surface. CONSTITUTION:A plate-shaped material 14 is set on press dies 15 and 16 and pressed to obtain a circular-arc commutator piece 12. Here, the pressure surface of the die 15 is slightly roughened. Convexes and concaves of the press die 15 and 16 are transferred onto the surface of the commutator piece to be molded under a pressure to finish the surface thereof at a coarseness of 1s-3s. This can abolish a special grinding process while finishing the surface of the commutator evenly with a better masproductivity, thereby stabilizing the commutation performance. |
