| 摘要 |
An optical receiver element 3 is mounted in a transparent part of stationary housing 1c of cylinder lock. Further a luminous element 10 is mounted on grip 6a of a mechanical key 6 for transmitting optical signals therefrom to the optical receiver 3. A source battery is mounted in the key grip 6a for energising the luminous element 3 and switch means provided in the key grip 6a control of energisation of the luminous element 3, e.g. according to pulsed coding. If the optical signal is received when the rotor of the lock is in the correct (unlocked) position then there will be no alarm. <IMAGE> |
