Automatic vehicle speed control device

Abstract

An automatic vehicle speed control device for use in an automatic controlling of the running speed of a vehicle to a certain set speed is disclosed. The device comprises a vehicle speed sensor for outputting vehicle speed data proportional to an actual vehicle speed, a command switch for outputting cruise command signals, an actuator for driving a throttle valve, a vehicle speed memory for memorizing the vehicle speed sensor data in accordance wth operation of the command switch, a decision device for deciding whether or not the decelerating control amount transmitted to the actuator is less than a given amount and the decelerating control time is continuing longer than the given time thereof during vehicle speed controlling, a setting device for setting a response constant W of the actuator larger by an offset value X is case where the decelerating control amount transmitted to the actuator is less than a given amount and the decelerating control time is continuing longer than the given time thereof in the decision device, and a control device for controlling an actuator by calculating the output time Y of an actuator driving signal on the basis of the difference between the actual vehicle speed and the memorized vehicle speed and calculating an actuator driving time TV in accordance with following relation TV=Y+W with the response constant W of actuator set by the setting device.