Borg-warner Automotive Gmbh

Borgwarner Inc.

Chrysler Corporation

Drew A Sundquist

Roger T Simpson

Alan L Miller

Will Watson

Dan Joseph Showalter

Diane K Ducklow

Joseph W Beckerman

Ward D McGinn

Todd L Perttola

An on demand vehicle drive system monitors vehicle performance and operating conditions and controls torque delivery to the vehicle wheels. The system includes a plurality of speed and position sensors, a transfer case having primary and secondary output shafts driving primary and secondary axles and a microcontroller. The sensors include a vehicle speed sensor, a pair of primary and secondary drive shaft speed sensors, and brake and driveline status sensors. The transfer case includes a modulating electromagnetic clutch controlled by the microcontroller which is incrementally engaged to transfer torque from the primary output shaft to the secondary output shaft. When the speed of either the front or the rear drive shafts overruns, i.e., exceeds, the speed of the other drive shaft by a predetermined value related to the vehicle speed, indicating that wheel slip is present, clutch current is incrementally increased to increase clutch engagement and torque transfer to the secondary axle. When wheel slip is reduced below the predetermined value the current to the clutch is incrementally reduced. The method of operating such a system is also described.

On demand vehicle drive system

An on demand venicle drive system monitors vehicle performance and operating conditions and controls torque delivery to the vehicle wheels. The system includes a plurality of speed and position sensors, a transfer case having primary and secondary output shafts driving primary and secondary axles and a microcontroller. The sensors include a vehicle speed sensor, a pair of primary and secondary drive shaft speed sensors, and brake and driveline status sensors. The transfer case includes a modulating electromagnetic clutch controlled by the microcontroller which is incrementally engaged to transfer torque from the primary output shaft to the secondary output shaft. When the speed of either the front or the rear drive shafts overruns, i.e., exceeds, the speed of the other drive shaft by a predetermined value related to the vehicle speed, indicating that wheel slip is present, clutch current is incrementally increased to increase clutch engagement and torque transfer to the secondary axle. When wheel slip is reduced below the predetermined value the current to the clutch is incrementally reduced. The method of operating such a system is also described.

An automatic transmission and transfer case operatively mounted in a four wheel drive vehicle controlled by a single selector lever that is moved to predetermined detented positions along a longitudinal gate to select the transmission drive ranges, reverse, neutral and park. A special pivot construction allows the selector lever to be moved laterally with respect to the normal longitudinal movement for transfer case gear ratio changes and neutral selection. A small lateral gate is employed to receive the selector lever located in alignment with the neutral detent position of the automatic transmission requiring the transmission to be in neutral when the transfer case is shifted. When moved into the lateral gate, the selector lever activates electronic controls effecting operation of a motor for shifting transfer case gear ratios and for selecting transfer case neutral.

Gated selector lever and controls for automatic transmission and

An on demand vehicle drive system monitors vehicle performance and operating conditions and controls torque delivery to the vehicle wheels. The system includes a plurality of speed and position sensors, a transfer case having primary and secondary output shafts driving primary and secondary drive shafts, differentials and axles and a microcontroller. The sensors include a vehicle speed sensor, a pair of primary and secondary drive shaft speed sensors, and brake and driveline status sensors. The transfer case includes a modulating electromagnetic clutch comprising a primary, cone clutch assembly which functions as a pilot device to actuate a secondary, disc pack clutch assembly. The electromagnetic clutch is controlled by the microcontroller which is incrementally engaged to transfer torque from the primary output shaft to the secondary output shaft. When the speed of either the front or the rear drive shaft overruns, i.e., exceeds, the speed of the other drive shaft by a predetermined value related to the vehicle speed and other variables, indicating that wheel slip is present, clutch current is incrementally increased to increase clutch engagement and torque transfer to the secondary drive shaft. When wheel slip is reduced below the predetermined value the current to the clutch is incrementally reduced. The system also senses and compensates for the speed differences between the primary and secondary drive axles caused by the use of different, mixed tire, sizes, e.g., a compact spare, at one or more tire locations by adjusting the predetermined value. The method of operating such a system is also described.

An electromagnetic clutch assembly (40) especially suitable for use in motor vehicle four wheel drive systems selectively provides power to the front drive components (26, 28, 30). The clutch assembly (40) includes a through drive shaft (42) about which a clutch armature (100), clutch rotor (110), output drive sprocket (76) and other components are coaxially disposed. The drive shaft (42) receives a plurality of spring biased fingers (56) which selectively couple the shaft (42) to the drive sprocket (76). The fingers are translated axially by a like plurality of cam lobes (122) on the rotor (110). A torsion spring (154) maintains the cam lobes (122) in alignment with the fingers (56). When an electromagnetic coil (130) adjacent the rotor (110) is activated, the drag from the associated front wheel drive components (26, 28, 30) slows the clutch armature (100) and the rotor (110), rotating the rotor (110) and cam lobes (122) relative to the drive shaft (42) and allowing the fingers (56) to translate axially, thereby coupling the output drive sprocket (76) to the drive shaft (42).

Growing community of inventors

Canton, MI, United States of America

Drew A Sundquist