| 摘要 |
<p>PURPOSE:To prevent a break of a key device and a car theft by disengaging a block piece from a rotor cover when a tapping screw is inserted against an urging force. CONSTITUTION:A block piece 60 is rotatably and axially movably disposed between a rotor 20 and a rotor cover 70 so that the piece 60 is urged by a spring 50 so as to be brought into contact with the cover 70. Next, a protrusion 63 is provided on one of the opposed surfaces 60 of the cover 70 and the piece 60, and an engaging part 73 is provided on the other surface. As a result, when the piece 60 is in contact with the cover 70, the protrusion 63 is engaged with the part 73 so that rotation of the piece 60 with respect to the cover 70 is restricted, and hence a key plate can be surely inserted. But if a tapping screw is inserted against the spring 50, the protrusion 63 is disengaged from the part 73 so that the piece 60 is caused to rotate together with the tapping screw, so that the tapping screw can not be screwed into the rotor 20.</p> |
