| 摘要 |
PURPOSE:To increase the lifetime of a brush by forming the material of a pressing spring of a brush for a motor of a shape memory alloy. CONSTITUTION:A brush 2 is formed to slide with a plurality of commutator segments 5 by the rotation of a motor, and the segments 5 are insulated by micas 6. Lead wirings 4 are respectively mounted at the brushes 2, and currents are supplied through the brush 2 to the segments 5. The surface, on which the brush 2 is slid with the segments 5, is provided with a spiral pressing spring 1 contacted at one end with the bottom 3-1 of a brush holder 3. A shape memory alloy is used for the material of the spring 1. Thus, the temperature rise of the commutator surface is transmitted to the spring 1, a voltage drop is reduced by increasing the pressing force, thereby lowering the raised temperature. |
