Methods and systems for engine shut-down control
AssigneeFord Global Technologies, LLC
InventorsAlex O'Connor Gibson, Peter John Grutter, Roger Lyle Huffmaster, Felix Nedorezov
Life of this patent
Estimating the term…
Abstract
An example method of operation comprises, selectively shutting down engine operation responsive to operating conditions and without receiving an engine shutdown request from the operator, maintaining the automatic transmission in gear during the shutdown, and during an engine restart from the shutdown condition, and with the transmission in gear, transmitting reduced torque to the transmission. For example, slippage of a forward clutch of the transmission may be used to enable the transmission to remain in gear, yet reduce torque transmitted to the vehicle wheels.
Claims14
A method of controlling a vehicle powertrain, comprising:
- shutting down an engine responsive to operating conditions and without receiving a shutdown request from an operator, the shutdown including engine idle-stop;
- maintaining an automatic transmission in gear during the shutdown;
- and
- during an engine restart from the shutdown, and with the transmission in gear and grounded, transmitting reduced torque to the transmission by increasing slippage of a transmission clutch to adjust a degree of grounding, wherein transmitting reduced torque to the transmission further includes actuating the transmission to internally lock the transmission and block transfer of input torque to vehicle wheels.
A method of controlling a powertrain of a vehicle, the powertrain including an engine and an automatic transmission, the powertrain coupled to driving wheels of the vehicle, the vehicle operated by an operator, the method comprising:
- selectively shutting down engine operation responsive to operating conditions and without receiving an engine shutdown request from the operator and maintaining the transmission in gear during the shutdown, the shutdown including engine idle-stop;
- during a first non-launch engine restart from the shutdown condition, and with the transmission still in gear and grounded, transmitting decreased torque through the transmission by internally locking and blocking transfer of input torque to the wheels;
- and
- during a second launch engine restart from the shutdown condition, and with the transmission still in gear, transmitting increased torque through the transmission to launch the vehicle.
A vehicle powertrain control method, comprising:
- shutting down an engine responsive to operating conditions and without receiving a shutdown request from an operator, the shutdown including engine idle-stop;
- maintaining an automatic transmission in gear during the shutdown;
- and
- during an engine restart from the shutdown with a clutch temperature above a threshold, and with the transmission in the maintained gear and grounded, adjusting transmitting transmission torque by adjusting a degree of transmission grounding, wherein the grounding includes grounding a transmission output shaft to a transmission case.
A method of controlling a vehicle powertrain, comprising:
- shutting down an engine responsive to operating conditions and without receiving a shutdown request from an operator, the shutdown including engine idle-stop;
- maintaining an automatic transmission in gear during the shutdown;
- and
- during an engine restart from the shutdown, and with the transmission in gear and grounded, transmitting reduced torque to the transmission by increasing slippage of a transmission clutch to adjust a degree of grounding, wherein the grounding includes grounding a transmission output shaft to a transmission case.
Dependencies are inferred from the claim text.