| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an engagement coupling used for fixing a rotation body at a plurality of predetermined angle positions, requiring small pressing force for engaging gears with each other, capable of maintaining high indexing accuracy when rotation force is applied, and also capable of avoiding reduction of the indexing accuracy or reduction of indexing rigidity caused by backlash of a spline part. <P>SOLUTION: The engagement coupling 6 is composed of a couple comprising a tapered spur gear 7 formed with an external tooth 16 whose tooth thickness on a cylindrical surface changes to be in a wedge shape to a tooth-width direction on a conical outer peripheral surface, and a tapered internal tooth gear 8 formed with an internal tooth 19 engaged with the tapered spur gear on a conical inner peripheral surface or on a regular polygonal pyramidal inner peripheral surface. By fastening an engagement part engaged with a spline 15 which axially/movably guides the tapered spur gear 7 or the tapered internal tooth gear 8 which advances/retreats at the time of engaging/disengaging, to an axis-perpendicular direction by wedge action, the rotation body 3 is indexed with high rigidity and high accuracy. <P>COPYRIGHT: (C)2010,JPO&INPIT |
