Lock key anti loss warning - has flashing light or buzzer operating when key withdrawn until correct storage

摘要

The car or house door key is fitted with a miniature battery which is cut off when the key is inserted. When pulled, the battery operates a flashing light and produces audible pips until it is inserted in a small case attached by a chain to the trousers or to the wall. When the car key is inserted in the ignition lock, button is depressed by the dashboard. The spring in the housing is compressed and the contacts are broken. When the key is withdrawn, the contacts actuate a battery in a circuit with a tone signal and a flashing light. For car keys, a retainer to make the signals inoperative can be attached to a chain sewn to the clothing of the user.