초록 ▼

An automatic speed control apparatus for controlling the running speed of a vehicle at a constant set speed includes an auxiliary intake passage providing direct communication between portions of a main intake passage upstream and downstream from a throttle valve so as to bypass the throttle valve,

An automatic speed control apparatus for controlling the running speed of a vehicle at a constant set speed includes an auxiliary intake passage providing direct communication between portions of a main intake passage upstream and downstream from a throttle valve so as to bypass the throttle valve, an auxiliary intake air valve adapted for controlling the flow rate of air in the auxiliary intake passage, and a fuel supply cut-off means for suspending the supply of fuel to the engine from a moment at which a fuel supply cut-off condition is met, which requires the throttle valve to be set at the minimum opening position and the engine speed to be higher than a predetermined fuel supply cut-off engine speed, until the moment at which a predetermined fuel supply recovery condition is met. An actuator for actuating the throttle valve is controlled so as to vary the degree of opening degree of the throttle valve and enable the vehicle to run at the constant set speed. The auxiliary intake air valve is controlled in such a manner that the flow rate of air in the auxiliary intake passage is reduced before the fuel supply cut-off condition is met during motion of the vehicle under the control of the automatic driving apparatus. The rate of fuel supply to the engine has therefore been reduced before the fuel supply is actually cut-off so that the amount of change in the engine output torque and, hence, the level of shock produced by the change in the engine output torque are reduced when cut-off of the fuel supply is executed.

대표청구항 ▼

An automatic speed control apparatus for controlling running speed of a vehicle at a constant set speed, said vehicle having an internal combustion engine, the speed control apparatus comprising: means for selectively activating said speed control apparatus; a surge tank provided with a main intake

An automatic speed control apparatus for controlling running speed of a vehicle at a constant set speed, said vehicle having an internal combustion engine, the speed control apparatus comprising: means for selectively activating said speed control apparatus; a surge tank provided with a main intake passage connected to said engine, and having a throttle valve therein; an auxiliary intake passage providing direct communication between portions of the main intake passage upstream and downstream of said throttle valve so as to bypass said throttle valve; an auxiliary intake air valve adapted for controlling a flow rate of air in said auxiliary intake passage; and fuel supply cut-off means for suspending supply of fuel to said engine from completion of a fuel supply cut-off condition until completion of a fuel supply recovery condition; an actuator means for controlling an opening degree of said throttle valve; a vehicle speed sensor for sensing an instant running speed of said vehicle; actuator control means for controlling said actuator means to coincide the sensed vehicle speed with a predetermined set vehicle speed so as to enable said vehicle to run at said set vehicle speed, said actuator control means comprising an actuator chamber in which at least a portion of said actuator means is positioned, a vacuum pump and means for providing communication between said surge tank and said actuator chamber so that said actuator means can be actuated by vacuum in said surge tank; and auxiliary intake air valve control means for controlling said auxiliary intake air valve such that a flow rate of air in said auxiliary intake passage is reduced before said fuel supply cut-off condition is met while said speed control apparatus is activated.