| 摘要 |
PURPOSE:To make it possible to perform high speed operation by a spiral groove having a large pitch, by moving a pin which is provided in the spiral groove that is provided in a thimble so that the pin is protruded from a spindle. CONSTITUTION:The part of the pin 7, which is protruded from the spindle 3, is inserted in the long groove 8A which is formed in the longitudinal direction of the outer surface of a hollow tube body 8. The part is pierced through said long groove 8A and further protruded from the groove. The tip part of the pin is engaged with the spiral groove 9A of the tubular thimble 9 which is rotatably supported by the outer surface of the hollow tube 8. A spindle rotation preventing means is constituted by the pin 7 as an engaging member and the hollow tubular body 8. |
