| 摘要 |
PROBLEM TO BE SOLVED: To allow normal driving operation by actuating a drive unit for automatic reset to a home position even when an output shaft runs idle relative to a motor. SOLUTION: This wiper motor 90 overcomes the resistance of a wave washer 56 when the output shaft 12 is reversed or constrained during operation of excessive outer force, whereby the output shaft 12 runs idle relative to an input disc 28. Thus, damage to parts or burnout of the motor is prevented. Meshing engagement portions 34, 36 of the input disc 28 which mesh and engage with each other in a normally working condition can mesh and engage with meshing engagement portions 50, 52 of a clutch disc 38 at only one preset position in a regular reciprocating rotation angle range of the output shaft 12. Thereby, automatic reset to the home position is allowed by actuating a motor body 92 and normal driving operation is allowed again by connecting the output shaft 12 to the motor body 92 at its fixed position. COPYRIGHT: (C)2005,JPO&NCIPI |
