WINCH FOR EXPANDABLE COLUMN AND PROJECTOR

摘要

PROBLEM TO BE SOLVED: To provide a winch which can be normally used only in a positive winding condition without creating a reverse winding condition by preventing the reverse of a drum when reverse operating a handle in error. SOLUTION: When a wire 6 is wound on the drum 13 by reverse rotating operation of the handle 12 in error, the drum 13 is threadedly moved to the direction of a stopper 21 to make a female screw portion 15 on the inner periphery of the drum 13 unthreaded from a male screw portion 14 on the outer periphery of a spindle 11 and the drum 13 idle run, preventing the reverse winding of the wire 6.