Adaptive vehicle drive system for extreme operating conditioning
First Claim
1. An adaptive vehicle drive system comprising, in combination,a first driveline having a first speed sensor,a second driveline having a second speed sensor,a transfer case for driving said first driveline and said second driveline a modulating clutch operably disposed between said first driveline and said second driveline, and a lockup clutch operably disposed between said first driveline and said second driveline,a microcontroller for receiving signals from said first and said second speed sensors anddetermining the average and instantaneous speed differences between said first driveline and said second driveline over a predetermined time period,determining the speed of the slower of said first and said second drivelines,comparing said average and instantaneous speed differences to said speed of said slower of said drivelines,providing signals sequentially to said modulating clutch and said lockup clutch to operably couple said first and said second drivelines in response to both said average speed difference and said instantaneous speed difference exceeding respective predetermined values relating to said speed of said slower of said drivelines.
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Accused Products
Abstract
An adaptive torque control and distribution system for a motor vehicle having a transfer case, primary driveline and drive wheels and secondary driveline and drive wheels for operation in extreme off road conditions such as sand. The transfer case includes a modulating clutch and a lockup clutch disposed in parallel between its primary (rear) output and secondary (front) output. The system detects abnormally high magnitude and rapidly repeating wheel spin transients which are characteristic of operation in sand or similar highly randomly variable tractive conditions and overrides the on demand torque distribution program for a predetermined time interval. During this predetermined time interval, the transfer case lockup clutch is activated thereby coupling the primary and secondary drivelines and achieving a fifty-fifty torque split therebetween while the modulating clutch is inactive. The system and this operating mode reduces clutch and clutch operator cycling thereby reducing heat generation within the transfer case and increasing clutch and transfer case longevity.
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Citations
20 Claims
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1. An adaptive vehicle drive system comprising, in combination,
a first driveline having a first speed sensor, a second driveline having a second speed sensor, a transfer case for driving said first driveline and said second driveline a modulating clutch operably disposed between said first driveline and said second driveline, and a lockup clutch operably disposed between said first driveline and said second driveline, a microcontroller for receiving signals from said first and said second speed sensors and determining the average and instantaneous speed differences between said first driveline and said second driveline over a predetermined time period, determining the speed of the slower of said first and said second drivelines, comparing said average and instantaneous speed differences to said speed of said slower of said drivelines, providing signals sequentially to said modulating clutch and said lockup clutch to operably couple said first and said second drivelines in response to both said average speed difference and said instantaneous speed difference exceeding respective predetermined values relating to said speed of said slower of said drivelines.
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8. An adaptive vehicle drive system for extreme off road conditions comprising, in combination,
a first driveline having a first drive shaft, first differential and first set of wheels, a second driveline having a second drive shaft, second differential and second set of wheels, a transfer case having a first output coupled to said first driveline, a second output coupled to said second driveline, a modulating clutch operably disposed between said first output and said second output and a lockup clutch operably disposed between said first driveline and said second driveline, a first sensor for sensing the speed of said first driveline, a second sensor for sensing a speed of said second driveline, a microcontroller for receiving signals from said first and said second sensors and determining an average speed difference between said first driveline and said second driveline over a first predetermined time period, determining a maximum instantaneous speed difference between said first driveline and said second driveline over said predetermined time period, determining the speed of the slower of said first and said second drivelines, sequentially activating said modulating clutch to operatively couple said first and said second drivelines in response to both said average speed difference and said maximum instantaneous speed difference exceeding said speed of said slower of said drivelines by respective predetermined values, activating said lockup clutch to directly couple said first driveline and said second driveline.
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16. A control system for an on demand vehicle drive system comprising, in combination,
a first sensor for sensing the speed of a first vehicle driveline, a second sensor for sensing the speed of a second vehicle driveline, microcontroller means for receiving signals from said first and said second sensors and determining the instantaneous speed difference between said first driveline and said second driveline, determining the average speed difference between said first driveline and said second driveline over a predetermined time period, determining the speed of the slower of said first and second drivelines, determining a threshold average speed which is greater than said slower shaft speed, comparing said average speed to said threshold speed, determining the maximum instantaneous speed difference during said predetermined time period, determining a threshold maximum speed difference which is greater than said slower shaft speed, providing a signal to engage a clutch to operatively couple said first and said second drivelines in response to both said average speed difference and said maximum instantaneous speed difference exceeding said threshold average and maximum speeds, respectively.
Specification