PURPOSE: To surely fix a locking body and a base plate upon inserting the protrusion of the base plate into the groove of the locking body.
CONSTITUTION: A fan-like section 46B is arranged in the inlet section of the locking groove 56 of a locking body. The holding body 30 connected to the fan-like section 46B is provided with a locking claw 85, which is provided with a slant face 90. A disk section 18 is provided with a recessed section 24 adapted to contain the locking claw 85 therein, and an inclined block 88 is projected in the vicinity of the opening of the recessed section 24. The inclined block 88 is provided with an inclined face 88A in the side opposed to the inclined face 90 of the locking claw 85. The holding body 30 is energized by a compression coil spring in a direction to let the locking claw 85 enter the recessed section 24. Since the holding body 30 is energized by the compression coil spring, and as a result, the locking claw 85 abuts on the inclined face 90 of the inclined block 88, if the operator set the holding body free, the fan-like section 46B can surely return to the inlet section of the locking groove 55. Therefore, the projection of a base plate can be surely held in the locking groove 55.
ARAMAKI KUNINORI
KAMIYAMA HIDEKATSU
BRIDGESTONE CORP