INDEXING DEVICE FOR MACHINE TOOLS

摘要

A cylindrical pressure-receiving member 34b is arranged in a space between a ring-shaped clamp sleeve 34a and a frame 31b such that the clamp sleeve 34a is fitted around a shaft 38b being integral with a rotary shaft 39. In an outer peripheral portion 34a2 of the clamp sleeve 34a, an annular groove 34a1 provided continuously over the entire circumference within an axial area of the outer peripheral portion 34a2 fitted into an inner peripheral portion 34b3 of the pressure-receiving member 34b provides a thin-wall portion 34a5. Also, a space surrounded by the annular groove 34a5 and the pressure-receiving member 34b provides a pressure chamber 34d communicating with a fluid control circuit. A predetermined gap 34d2 is provided between an inner peripheral surface 31b4 of the through hole 31b1 of the frame and an outer peripheral surface 34b2 of the pressure-receiving member 34b.