| 摘要 |
<p>PURPOSE:To generate an alarm when a locking device is unjustly operated by providing the locking device with a cylinder lock and a lock release detecting switch functioning when the cylinder lock is operated using a regular key. CONSTITUTION:When a foreign matter is inserted into a locking device in an armed state to actuate a key insertion detecting switch 27, which is turned on. An R/S flip flop 106 is therefore set through a delay circuit 93, a pulse forming circuit 100 and an AND gate 98 to check the driving of a starter circuit 112. A timer circuit 107 is simultaneously actuated to give an intermittent signal through an AND gate 108 to the base of a transistor 109. Thus an alarm device 110 is operated for several minutes. When a lock release detecting switch 80 is turned on in the armed state where a flip flop 97 is kept at a set state, and in an armed preparing state where a timer circuit 96 is in operation, the circuit 95 is cleared to turn into the disarmed state.</p> |
