Claims
- 1. A system for measuring engine torque including:
an engine having an engine output shaft; a driveshaft operably connected to said engine output shaft to provide driving input to an axle differential; a sensor assembly having a portion mounted to said driveshaft for measuring the twist of said driveshaft; and a processor for determining engine torque based on driveshaft twist to control predetermined engine parameters based on the engine torque.
- 2. A system according to claim 1 including a transmission coupled to said engine output shaft and having a transmission output shaft coupled to said driveshaft wherein said sensor assembly is mounted on said driveshaft between said transmission and said axle differential.
- 3. A system according to claim 2 wherein said sensor assembly includes a position target supported on said driveshaft, at least one laser for generating a beam to scan said target, and at least one photo receiver for receiving a reflected beam from said position target.
- 4. A system according to claim 3 wherein said position target is comprised of a first specified pattern including reflective and non-reflective surfaces placed on said driveshaft at a first location and a second specified pattern including reflective and non-reflective surfaces placed on said driveshaft, said second specified pattern being spaced apart from said first specified pattern by a predetermined distance.
- 5. A system according to claim 4 wherein said first and second specified patterns are comprised of a plurality of spaced apart lines having variable thicknesses compared to each other.
- 6. A system according to claim 5 wherein said driveshaft defines a longitudinal axis and said lines are placed about the circumference of the driveshaft parallel to said longitudinal axis.
- 7. A system according to claim 4 wherein said at least one laser is comprised of a first laser aimed at said first specified pattern and a second laser aimed at said second specified pattern and wherein said at least photo receiver is a first photo receiver mounted adjacent to said first laser to receive a first reflected beam from said first specified pattern and a second photo receiver mounted adjacent to said second laser to receive a second reflected beam from said second specified pattern.
- 8. A system according to claim 7 wherein said processor compares data from said first photo receiver to data from said second photo receiver to determine driveshaft twist.
- 9. A system according to claim 1 wherein said engine includes a plurality of cylinders actuated by rotation of a crankshaft and wherein said processor includes a timing mechanism such that an individual torque value can be assigned to each of said cylinders.
- 10. A method for measuring engine torque comprising the steps of:
(a) mounting a portion of a sensor assembly on a driveshaft; (b) measuring the twist of the driveshaft; and (c) determining engine torque based on the twist measurement.
- 11. A method according to claim 10 wherein step (a) further includes mounting the sensor assembly on the driveshaft between a transmission and drive axle.
- 12. A method according to claim 11 wherein step (b) further includes optically measuring the twist with at least one laser and photo receiver.
- 13. A method according to claim 10 wherein step (a) further includes forming a first specified pattern on the driveshaft, forming a second specified pattern on the driveshaft at a predetermined distance from the first specified pattern, scanning the first specified pattern with a first laser, receiving a first reflected beam from the first laser with a first photo sensor, scanning the second specified pattern with a second laser, and receiving a second reflected beam from the second laser with a second photo sensor.
- 14. A method according to claim 13 including the step of comparing data from the first and second reflected beams to determine driveshaft twist.
- 15. A method according to claim 14 including the steps of forming a first index in the first specified pattern to establish a first baseline reference, forming a second index in the second specified pattern to establish a second baseline reference, aligning the first index with the second index along the driveshaft, and performing a calibration to account for any offset between the first and second indices.
- 16. A method according to claim 10 including measuring the twist of the driveshaft multiple times during each revolution of the driveshaft to form a torque profile and reading the torque profile at 120 degree increments for two revolutions to individually assign torque values to each cylinder in a six cylinder engine.
- 17. A method according to claim 10 including measuring the twist of the driveshaft multiple times during each revolution of the driveshaft to form a torque profile and reading the torque profile at 90 degree increments for two revolutions to individually assign torque values to each cylinder in an eight cylinder engine.
- 18. A sensor assembly for measuring engine torque including:
a first pattern formed on a driveshaft; a second pattern formed on the driveshaft at a predetermined distance from the first pattern; a first laser mounted to a vehicle structure for generating a first beam to scan the first pattern; a second laser mounted to the vehicle structure for generating a second beam to scan the second pattern; a first photo receiver mounted adjacent to said first laser for receiving a reflected beam from said first pattern; a second photo receiver mounted adjacent to said second laser for receiving a reflected beam from said second pattern; and a processor for comparing data from said first and second photo receivers to determine driveshaft twist and for deriving an engine torque value based on the driveshaft twist.
- 19. An assembly according to claim 18 wherein said first and second patterns are comprised of a plurality of longitudinally extending lines having varying thicknesses compared to each other and being spaced about the circumference of the driveshaft.
RELATED APPLICATION
[0001] This application claims priority to provisional application 60/186,582 filed on Mar. 2, 2000.
Provisional Applications (1)
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Number |
Date |
Country |
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60186582 |
Mar 2000 |
US |