PURPOSE: To prevent a rotary shaft from being strongly pressed locally to the inner periphery of a bush even if the axial direction of the rotary shaft inserted into a tube section is inclined to the axial direction of the tube section by providing a taper face on the inner periphery of the tube section of the bush.

CONSTITUTION: A bush 30 is fitted to a support hole 1b on the side wall 1B of a seat belt retractor for use, for example. Even if the axial line of a shaft 2 is inclined against the axial line of the bush 30, the outer periphery of the shaft 2 is not pressed to the inner periphery of the bush 30 because a taper face 33 is provided on the inner periphery of a tube section 31. A taper face 35 is provided on a flange section 32, thus the plate face of a ratchet wheel 11 is not pressed to the plate face of the flange face 32. A taper face 34 is provided on the outer periphery of the tube section 31, and a gap 36 is formed between the outer periphery of the tube section 31 and the inner periphery of the support hole 1b, thus the end section 31 A of the tube section 31 can be deviated in the direction of the arrow against the end section 31B.