Vehicle constant speed driving apparatus

摘要

Vehicle constant speed driving apparatus including a solenoid of a releasing valve for directing atmosphere into a hydraulic actuator when the releasing valve solenoid releases a constant speed driving which is in ON-condition (not causing ON-OFF repeated operation) in order to isolate an interior chamber of the hydraulic actuator from the atmosphere during the constant speed driving, and a modulator valve solenoid located adjacent to a releasing valve solenoid so that both solenoids are held in a substantially same thermal condition. The current flowing to the releasing valve solenoid is controlled to a constant value and a voltage varied by such constant current control is applied to the modulator valve solenoid to compensate for changes in the temperature of and the voltage supplied to the modulator valve solenoid, thereby maintaining at a constant value the current flowing to the modulator valve solenoid and providing a vehicle constant speed driving apparatus for minimizing a variation in the driving speed.