Automatic car lighting system - has lamps lit and extinguished via ambient light sensor when ignition system is switched on

摘要

The car lighting system lights and extinguishes the lamps automatically according to the ambient light intensity. It also warns the driver if he leaves the car with the lights on. This is done by an audible alarm (9). The positive of the alarm is joined to a transistor output (6). The alarm is polarised and placed between the output side of the lighting switch (7) and the ignition system (8) contact. The transistor feeds the lamps when teh contact (8) is closed. Automatic lighting is by a transistor bridge and a photosensor (I) of resistance type.