CRIME PREVENTIVE THUMB-TURN MECHANISM

PROBLEM TO BE SOLVED: To improve crime preventive performance, by making fraudulent unlocking of a thumb-turn difficult, by hooking or pushing a wire or a bar inserted from clearance on or to a knob, without installing a cover. SOLUTION: This crime preventive thumb-turn mechanism 1 is composed of a cylindrical outer cylinder 2, the thumb-turn 5 composed of a shaft 3 and the knob 4, a thumb-turn core 6 for changing the rotational movement of the thumb-turn 5 to protruding-retreating motion of a block rod, an inner cylinder 7 coaxially and rotatably arranged in the outer cylinder 2, and rotating in response to the rotational movement of the thumb-turn core 6, and a slipping-out preventive stopper 8 fixedly installed on a thumb-turn shaft 3, and preventing slipping-out of the thumb-turn 5 from the outer cylinder 2. The thumb-turn mechanism is constituted by arranging a pressing piece 9 for pressing the thumb-turn shaft on an inner peripheral surface of the inner cylinder 7, and arranging a cutout part 10 for dropping in the pressing piece 9 on the thumb-turn shaft 3. COPYRIGHT: (C)2005,JPO&NCIPI