Nissan Motor Company Limited

Yohsiyuki Etoh

Hiroshi Tanaka

Yasuhisa Takeuchi

A system and method for automatically controlling a vehicle speed to a desired cruise speed are disclosed in which when at least one of conditions that any one of command signals from corresponding operation command switches is outputted and that a microcomputer of the automatic cruise speed controlling system normally operates and outputs control command signals indicating that corresponding one of control valves is energized is satisfied, the power supply to the control valves is enabled. On the contrary, when at least one of conditions that none of the command signals from the corresponding command switches is outputted and that the microcomputer erroneously outputs control command signals indicating that the corresponding one of the control valves is energized is satisfied, the power supply to the control valves is disabled. The control valves cause air pressure in a chamber defined by a diaphragm to be adjusted, the diaphragm being linked to an engine throttle valve, so that an opening angle of the throttle valve is adjusted to control the vehicle speed.

Growing community of inventors

Kanagawa, Japan

Yohsiyuki Etoh