| 摘要 |
A vehicle alarm comprises a control unit (2) coupled to an R.F. receiver (4) for receiving a deadlock signal from a remote transmitter (6). When the signal is received, a vehicle to which the alarm is fitted is locked and an ultrasonic movement sensor (8) is activated. The sensor (8) is allowed to stabilise for a predetermined delay period. If after a further predetermined time, no movement has been detected, the vehicle is deadlocked. The alarm minimises the risk of someone being deadlocked in the vehicle. |
