| 摘要 |
PURPOSE:To stably obtain tightening torque to a fixed value, by connecting and disconnecting an engaging member with a low speed output shaft and a draw bolt by a mechanical clutch and utilizing rotary energy in a system of the low speed output shaft for tightening of the draw bolt. CONSTITUTION:A reduction member G, using a small motor M as a driving source, is connected by a flexible shaft joint J, while an output shaft 21 of this reduction member G is enabled to move in an axial direction. While the output shaft 21 is engaged with a shaft cylinder 30', 31 by a helical protrusive strip 21c, and this shaft cylinder 30', 31, being urged by a weak spring 34 to a side of the motor M, is rotatably key fitted to a cylindrical unit 25 not turned by the output shaft 21 in a racing condition due to the brake action. While an engaging member, respectively engaging with a thrust part 50b and an engaging tooth 50c provided in the tail end of a draw bolt 50, is provided in the end of the output shaft 21 and the shaft cylinder 30', being automatically connected with the draw bolt 50 by advancing the output shaft 21 or the shaft cylinder 30' to be moved by a left and a right roll start of the output shaft 21. |
