Nissan Motor Company Limited

Yuuji Katou

Kiyoshi Yoshida

In order to prevent hunting between a selected gear ratio (e.g. overdrive) and the next lower one, when a vehicle ascends a slope or incline under 'cruise control' an automatic speed control device (ASCD) which controls the opening of the engine throttle under the cruise control mode, upon being put into operation issues a control signal to the transmission control circuit which allows the latter to upshift the transmission to the predetermined gear ratio (viz., overdrive) and which renders the transmission control circuit incapable of downshifting to the next lower gear while the ASCD is functioning. Upon the vehicle speed falling a predetermined amount below the preselected target value, the ASDC issues a signal directly to the transmission to cause a downshift to the next lower gear ratio. Following such a downshift, the ASDC inhibits subsequent upshifting either for a predetermined period of time or until the load which necessitated the downshift disappears.

Method and apparatus for automatic transmission cruise control

In order to prevent hunting between a selected gear ratio (e.g. overdrive) and the next lower one when a vehicle ascends a slope or incline under 'cruise control', the degree to which which the cruise control arrangement (viz., the automatic vehicle speed control device (ASCD)) can open the throttle valve is limited to a value at which the transmission control circuit (e.g. hydraulic) will induce a downshaft. Upon a downshift being necessary to maintain vehicle speed, upshift is inhibited either for a predetermined period of time or until the load which necessitated the downshaft disappears.

Growing community of inventors

Zama, Japan

Yuuji Katou