VACUUM PUMP MOTOR CONTROLLING CIRCUIT

摘要

PURPOSE:To decrease the frequency of ON-OFF switching of a relay and a motor and to obtain a sufficient air pressure, by providing a vacuum switch and a timer in a vacuum pump motor controlling circuit. CONSTITUTION:Air pressure produced by a pump 6 is stored in a vacuum reservoir 7. This air pressure is applied to a hydraulic means 10 for producing hydraulic pressure when a brake pedal 9 is depressed so that an increased brake force is transmitted to a link 11 connected to brake shoes or the like. When a vacuum switch 8 is changed and when a key switch 2 is turned ON, a transistor 4 is turned ON for a certain while by producing a trigger from a trigger generating circuit 13 and actuating a one-shot multivibrator 12 by this trigger.