Vehicle restrain system monitoring electronic equipment - has duplicate warning lamps and cross-coupled transistor switches ensuring that one lamp fulfils alarm function

摘要

A warning is given by lamps (2A,2B) turned on by transistor switches (TE1,TE2) with emitters connected separately to earth (4A,4B) and cross-coupled to those of further transistors (TA1,TA2). The bases of these are addressed by a controller (6) which checks for fault conditions such as loss of continuity to earth (4A,4B). In such circumstances one or other of the lamps (2A,2B) can pass current to the intact connection so that the necessary visual warning is given. USE/ADVANTAGE - In occupant safety restraint systems (airbag, seat belts) of motor vehicle. Alarm function can be fulfilled even after failure of connection.