| 摘要 |
For the protection of door locks, especially of motor vehicles, the lock-cylinder housing is provided with an alarm-emitting switch which has a stator (11) aligned with the cylinder housing and connected fixedly in terms of rotation to the latter. Mounted rotatably in the stator (11) is a rotor (51) which is itself connected to the lock cylinder rotatable by means of the key after release. The stator contains two mutually coaxial electrical conductor tracks (28, 32) which partially overlap one another at an angle. In order to transfer the switch automatically into its operational state during the blocking of the lock, an electrically conductive wiper (67) is connected to a driver (66) on the rotor and is thus drawn into contact with the two conductor tracks. Its length is selected so that, during the backward movement of the key into its withdrawal position, the wiper (67) still always remains in the region of contact with the two conductor tracks. If the lock is to be opened again without the emission of an alarm, the key is first rotated opposite to the opening direction and the wiper is thereby drawn out of its contact position. <IMAGE> |
