Patent ID: 6104976
Filing Date: 2000-08-15
Classification: B60K,B60W,F16H,Y10T

Abstract:
A vehicle speed control system comprising:a speed setting section for setting a command vehicle speed;a vehicle speed sensing section for sensing an actual vehicle speed;a driving force calculating section for calculating a command driving force required to make the actual vehicle speed equal to the command vehicle speed;an engine output calculating section for calculating a command engine output in accordance with the command driving force and the command vehicle speed;a discriminating section for examining the command driving force to determine whether the command driving force is negative;a command engine speed calculating section for storing a predetermined engine torque-versus-engine-speed characteristic relationship in an engine constraint state in which a throttle is fully closed and fuel cutoff is inhibited and for calculating a command engine speed corresponding to the command engine output, from the predetermined engine torque-versus-engine-speed characteristic relationship in the engine constraint state when the command driving force is negative;a transmission ratio calculating section for calculating a command transmission ratio in accordance with the command engine speed;an engine controlling section for putting an engine in the engine constraint state when the command driving force is negative; anda transmission controlling section for controlling a continuously variable transmission in response to the command transmission ratio when the command driving force is negative.