| 摘要 |
PROBLEM TO BE SOLVED: To abruptly reduce a resistance available when a housing and a carrier coaxially disposed within the housing relatively rotate, by providing a traction means in a guide path of an inner side of the housing, which is drawn out of the guide path so as to be wound around the carrier by rotation of the carrier. SOLUTION: An annular housing 10 is formed with a guide path 20 in its inner side, while a carrier 40 is coaxially disposed within the housing 10 such that the carrier 40 can rotate to the housing 10. A traction means 22 extending along the guide path 20 is fixed to the carrier 40. The traction means 22 is drawn out of the guide path 20 so as to be wound around the carrier 40 by rotation of the carrier 40 to the housing 10. Thus the traction means 22 are drawn out of the guide path 20 when the housing 10 and the carrier 40 is relatively rotated, so that an available resistance can be abruptly reduced. |
