Cruise control apparatus for a vehicle using a control quantity to actuate the throttle and a control quantity integrator to actuate the gear change determiner

A cruise control apparatus for a vehicle, comprising:

• a) a speed sensor for sensing a speed at which the vehicle is travelling, and for generating a corresponding speed signal;
• b) acceleration sensing means for successively sensing an acceleration of the vehicle at predetermined intervals based on the output signal from said speed sensor;
• c) a target speed setter for setting a target speed at which the vehicle is to travel;
• d) target speed signal generating means for generating a target speed signal representative of the target speed;
• e) speed deviation calculating means for calculating, based on the speed signal and the target speed signal, a deviation between the target speed and the actual vehicle speed and for generating a corresponding output signal;
• f) control quantity calculating means for calculating a control quantity for controlling a driving force of the vehicle based on the output signals from said acceleration sensing means and said speed deviation calculating means;
• g) throttle valve actuating means for driving a throttle valve in an engine of the vehicle based on the output signal from said control quantity calculating means;
• h) control quantity integrating means for integrating the control quantity from the control quantity calculating means with respect to time;
• i) gear ratio change determining means for determining whether a gear ratio is to be changed based on the output signal from said acceleration sensing means, said speed deviation calculating means and said control quantity integrating means;
• wherein the integration performed by said control quantity integrating means is based on an output signal feedback from the gear ratio change determining means;
• and
• j) an automatic transmission operable to change its gear ratio in response to the output signal feedback from said gear ratio change determining means.