Voltage regulator for an alternator having an auxiliary stage for starting the alternator at a low rotational speed

DETAILED DESCRIPTION The object of the present invention is to construct a voltage regulator of the monofunction type for an alternator of the nine-diode type, whose actuator stage is formed as an integrated circuit and gives rise to a comparatively low voltage drop at the time of starting of the alternator.
This object is achieved by the voltage regulator defined and set out in the claims attached to this description.
This object may be effected by providing a voltage regulator for an alternator having first and second supply terminals and comprising a control stage connected between said first and second supply terminals and having an output terminal connected to a base of a first transistor of a pair of transistors forming part of an actuator stage of said regulator, said pair of transistors being connected together in a Darlington configuration and having their collectors connected to an exciter winding of said alternator, the improvement comprising an auxiliary stage connected between said first and second supply terminals, and having an output terminal connected to a base of a second transistor of said pair of transistors of said actuator stage and comprising a determining circuit means for determining a reference voltage and control circuit means for causing said second transistor of said pair of transistors to conduct when a voltage between said first and second supply terminals is lower than said reference voltage, thereby reducing a voltage drop across said pair of transistors.