Vehicle locking appts. - has key with rechargeable battery, rectifier and coil, inductively coupled to transmitter coil in lock by ferromagnetic shaft of key

摘要

The lock (2) has a transmitter coil (22) supplied with an a.c. or pulsed d.c. voltage. The key (1) contains a rechageable battery (3) which is coupled to a receiver coil (14) via a rectivier (15). The battery supplies power to a load (13) which may be a remote control circuit for locking and unlocking the door locks. The shaft of the key to made from ferromagnetic material so that the transmitter coil and receiver coil are inductively coupled when the key is inserted into the lock. The key may be inserted into the vehicle ignition lock, allowing the battery to be charged slowly. ADVANTAGE - Improved inductive coupling between lock and key allowing rise of small, concentrated magnetic fields.