FIXING DEVICE

PROBLEM TO BE SOLVED: To rotate a collar and a cone keeping them combined and to easily release the interference which is caused by the collar contacting a tubular housing and preventing the rotary operation by increasing the combining force of the collar and the cone. SOLUTION: An engaging recess 28 and an engaging protrusion 35 are formed at the bottom end of a square pillar-shaped main body 21 and the bottom end of a shaft 31. The recess 28 and the protrusion 35 are mutually separated and face each other vertically when the cone 3 and the collar 2 are in the first rotary position where the horizontal longitudinal direction of the main body 21 and the horizontal longitudinal direction of a quadrangular pyramid-shaped head 32 are matching each other. When the cone 3 is pushed up from the underneath when the cone 3 is in the first rotary position, the protrusion 35 on the cone 3 side approaches the recess 28 on the collar 2 side and the collar 2 and the cone 3 are mutually engaged to be combined to enable the simultaneous rotary operation of the collar 2 and the cone 3. COPYRIGHT: (C)2007,JPO&INPIT