Forward and aft torque distribution control system for 4WD vehicle and method
AssigneeNissan Motor Co., Ltd.
InventorsYoshiyuki Fukuda, Norio Iida
Life of this patent
Estimating the term…
Abstract
A forward and aft torque distribution system and a method of controlling forward and aft torque distribution for a four-wheel vehicle having an electronically controlled clutch to control split of drive torque to be transferred to front and rear wheels are disclosed. A 4WD controller is responsive to mode selection signals from a mode changeover switch and a vehicle speed signal delivered from a vehicle speed sensor, and has control modes involving at least a LOCK mode and an AUTO mode. When the vehicle speed becomes less than a vehicle's halt discriminative vehicle speed indicative of a vehicle's halt state during the LOCK mode, the controller allows the electronically controlled clutch to be released.
Claims9
A forward and aft torque distribution control system for a four-wheel drive vehicle comprising:
- an electronically controlled clutch controlling forward and aft torque distribution to be transferred to front and rear wheels;
- a mode changeover switch selectively producing mode selection signals comprising at least a LOCK mode selection signal and an AUTO mode selection signal;
- a vehicle speed sensor detecting a vehicle speed and producing a vehicle speed signal;
- and
- a controller responsive to the mode selection signals and the vehicle speed signal and controlling the electronically controlled clutch to control forward and aft torque distribution to be split to front and rear wheels,
- wherein the controller has control modes involving at least a LOCK mode to allow the electronically controlled clutch to be locked in a coupled state, and an AUTO mode to allow the electronically controlled clutch to be automatically controlled so as to alter forward and aft torque distribution depending on running conditions of a four-wheel drive vehicle,
- and wherein after the vehicle speed becomes less than a speed indicative of a vehicle's halt state and before the vehicle speed reaches to zero during the LOCK mode, the controller allows the electronically controlled clutch to be released so as to cause coupling torque of the electronically controlled clutch to become zero.
A forward and aft torque distribution control system for a four-wheel drive vehicle comprising:
- an electronically controlled clutch controlling forward and aft torque distribution to be transferred to front and rear wheels;
- mode changeover means for selectively producing at least a LOCK mode selection signal and an AUTO mode selection signal;
- vehicle speed sensor means for detecting a vehicle speed and producing a vehicle speed signal;
- and
- 4WD control means for controlling the electronically controlled clutch to control forward and aft torque distribution to be split to front and rear wheels, responsive to the mode selection signals and the vehicle speed signal,
- wherein the 4WD control means has control modes involving at least a LOCK mode to allow the electronically controlled clutch to be locked in a coupled state, and an AUTO mode to allow the electronically controlled clutch to be automatically controlled so as to alter forward and aft torque distribution depending on running conditions of a four-wheel drive vehicle, and
- wherein after the vehicle speed becomes less than a speed indicative of a vehicle's halt state and before the vehicle speed reaches to zero during the LOCK mode, the 4WD control means allows the electronically controlled clutch to be released so as to cause coupling torque of the electronically controlled clutch to become zero.
A method of controlling forward and aft torque distribution control for a four-wheel drive vehicle, comprising:
- preparing an electronically controlled clutch to control drive torque to be transferred to front and rear wheels;
- preparing a controller having control modes involving at least a LOCK mode to allow an electronically controlled clutch to be locked in a coupled state, and an AUTO mode to allow the electronically controlled clutch to be automatically controlled so as to alter forward and aft torque distribution depending on running conditions of a four-wheel drive vehicle;
- selectively producing mode selection signals involving at least a LOCK mode selection signal and an AUTO mode selection signal;
- detecting a vehicle speed and producing a vehicle speed signal;
- and
- controlling the electronically controlled clutch with the controller to control forward and aft torque distribution to be split to front and rear wheels in response to the mode selection signals and the vehicle speed signal such that after the vehicle speed becomes less than a speed indicative of a vehicle's halt state and before the vehicle speed reaches zero during the LOCK mode, the controller allows the electronically controlled clutch to be released so as to cause coupling torque of the electronically controlled clutch to become zero.
Dependencies are inferred from the claim text.