Method and apparatus for measuring driveline angles

• US 6,490,540 B1
• Filed: 11/15/2000
• Issued: 12/03/2002
• Est. Priority Date: 11/15/2000
• Status: Expired due to Fees

• Current Assignee: ArvinMeritor Technology LLC (Meritor, Inc. (Nevada))
• Original Assignee: Meritor Heavy Vehicle Technology, LLC (Cummins Incorporated)
• Inventors: Keeney, Christopher S., Kyrtsos, Christos, Brissette, Ronald N., Oates, Jack Darrin, Hawkins, Jim, Sanko, Tom, Kurzeja, Patrick
• Primary Examiner(s): Hilten, John S.
• Assistant Examiner(s): Sun, Xiuqin
• Application Number:
  US09/713,093
• Time in Patent Office: 748 Days
• Field of Search: 280/5.5, 734/57, 180/403, 101/116, 702/151
• US Class Current: 702/151
• CPC Class Codes: B60G 17/0152 characterised by the action on a particular type of suspension unit B60G17/01941 takes precedence
• CPC Class Codes: B60G 17/016 characterised by their responsiveness, when the vehicle is travelling, to specific motion, a specific condition, or driver input B60G17/017 takes precedence
• CPC Class Codes: B60G 17/0195 characterised by the regulation being combined with other vehicle control systems conjoint control of vehicle sub-units including control of suspension systems B60W10/22
• CPC Class Codes: B60G 2300/02 Trucks; Load vehicles
• CPC Class Codes: B60G 2400/252 vertical
• CPC Class Codes: G01C 1/00 Measuring angles

Abstract

A system measures multiple operational angles of a driveline assembly and compares the signals to each other to determine whether the angles and the respective driveline components are properly balanced. Different types of sensor assemblies can be used to measure the operational angles including various types of contact and non-contact sensors. In one example, the operational angle between one axle differential case and a corresponding universal joint can be compared to the operational angle between another axle differential case and corresponding universal joint mounted at an opposite end of the driveline. If the angles are equal or very close to one another than the angles are properly balanced. If the ratio between the two angles exceeds a predetermined limit, the driveline components are not properly balanced and the components can be repositioned to avoid premature wear.

Claims

1. A method of determining operational angles of driveline components comprising the steps of:

(a) providing a first axle assembly and a second axle assembly interconnected by a driveline component having universal joint assemblies mounted at opposing ends;

(b) measuring a first operational angle between the first axle assembly and one of the universal joint assemblies;

(c) measuring a second operational angle between the second axle assembly and the other of the universal joint assemblies;

(d) comparing the second operational angle to the first operational angle to determine a mismatch ratio; and

(e) generating an indicator signal if the mismatch ratio exceeds a predetermined limit.

2. A method as set forth in claim 1, including the step of (f) transmitting the indicator signal to a warning device to alert a vehicle operator that the mismatch ratio has been exceeded.

3. A method as set forth in claim 1, including the steps of (f) transmitting the indicator signal to a central processing unit;

and (g) generating a control signal for actively adjusting an adjustment component until the mismatch ratio is less than the predetermined limit.

4. A method as set forth in claim 1, wherein steps (b) and (c) include mounting at least one accelerometer to each of the first and second axle assemblies, measuring the acceleration due to gravity at each of the accelerometers, and determining the first and second operational angles based on gravity measurements.

5. A method as set forth in claim 1, wherein step (a) includes providing mounting plates on each of the first and second axle assemblies and steps (b) and (c) include mounting at least one proximity pickup coil to each of the mounting plates in a plane parallel to the mounting plates, suspending a magnetic member from each of the axle assemblies;

measuring the distance of separation between the coil and the magnetic member, and determining the first and second operational angles based on the separation measurements.

6. A method as set forth in claim 1, wherein steps (b) and (c) include mounting a first fluid sensor to the first axle assembly, mounting a second fluid sensor to the second axle assembly;

measuring a first fluid level for the first axle assembly with the first fluid sensor;

measuring a second fluid level for the second axle assembly with the second fluid sensor; and

determining the first and second operational angles based on the first and second fluid levels.

7. A method as set forth in claim 6, including the step of comparing the first and second fluid levels to a base fluid level that is parallel to the ground to determine the first and second operational angles.

8. A method as set forth in claim 1, wherein steps (b) and (c) include mounting a first potentiometer to the first axle assembly, mounting a second potentiometer to the second axle assembly, generating a first signal corresponding in magnitude to the first operational angle with the first potentiometer, and generating a second signal corresponding in magnitude to the second operational angle with the second potentiometer.

9. A method as set forth in claim 1, wherein steps (b) and (c) include mounting a first photo sensor to the first axle assembly, mounting a second photo sensor to the second axle assembly, mounting a first photo detector to the universal joint assembly closest to the first axle assembly, mounting a second photo detector to the universal joint assembly closest to the second axle assembly, generating a first photo signal to determine the first operational angle, and generating a second photo signal to determine the second operational angle.

10. A method as set forth in claim 1, wherein steps (b) and (c) include mounting a first proximity sensor adjacent to one of the universal joint assemblies, mounting a second proximity sensor adjacent to the other of the universal joint assemblies;

measuring the separation between the first proximity sensor and the one of the universal joint assemblies, measuring the separation between the second proximity sensor and the other of the universal joint assemblies, and determining the first and second operational angles from separation measurements.

11. A method as set forth in claim 1, wherein steps (b) and (c) include mounting a camera on a vehicle structural member adjacent to the driveline component, scanning the first axle assembly, the drive line component, the universal joint assemblies, and the second axle assembly to generate an image;

digitizing the image to generate digital data; and

determining the first and second operational angles based on the digital data.

12. A driveline assembly comprising:

a first drive axle having a first center differential with a first input and a first output;

a second drive axle having a second center differential with a second input;

a driveline component interconnecting said first and second axles at opposing ends and defining a central axis;

a first universal joint assembly connecting a first end of said driveline component to said first output and defining a first operational angle between said first center differential and said central axis;

a second universal joint assembly connecting a second end of said driveline component to said second input and defining a second operational angle between said second center differential and said central axis;

at least one sensor assembly mounted adjacent to said driveline component for measuring said first and second operational angles wherein said sensor assembly generates a first signal corresponding in magnitude to said first operational angle and a second signal corresponding in magnitude to said second operational angle; and

a processor for comparing said first signal to said second signal to generate a mismatch ratio.

13. An assembly as set forth in claim 12 wherein said processor is operationally linked to an indicator mechanism and generates an activation signal for activating said indicator when said mismatch ratio exceeds a predetermined limit.

14. An assembly as set forth in claim 12 wherein said processor is operationally linked to an adjustment mechanism and generates an activation signal to activate said adjustment mechanism to adjust a vehicle parameter to correct said first and second operational angles when said mismatch ratio exceeds a predetermined limit.

15. An assembly as set forth in claim 12 wherein said at least one sensor assembly includes a camera mounted to a vehicle structural member and defining a central scan axis that is perpendicular to said central axis, said camera having a scanner for generating a scanned image of said first and second drive axles, said first and second universal joint assemblies, and said driveline component.

16. An assembly as set forth in claim 15 wherein said camera includes a digitizing component that converts said scanned image into digital data for generating said first and second signals corresponding in magnitude to said first and second operational angles.

17. An assembly as set forth in claim 12 wherein said at least one sensor assembly is comprised of a first proximity sensor mounted to a vehicle structure adjacent to said first universal joint assembly and orientated in a position parallel to ground level and a second proximity sensor mounted to a vehicle structure adjacent to said second universal joint assembly and orientated in a position parallel to ground level, said first proximity sensor for sensing a first distance from said first proximity sensor to said first universal joint assembly and generating said first signal corresponding in magnitude to said first operational angle based on said first distance, and said second proximity sensor for sensing a second distance from said second proximity sensor to said second universal joint assembly and generating said second signal corresponding in magnitude to said second operational angle based on said second distance.

18. An assembly as set forth in claim 12 wherein said at least one sensor assembly is comprised of a first photo sensor mounted on said first center differential, a first photo detector mounted on said first universal joint assembly parallel to said central axis, a second photo sensor mounted on said second center differential, and a second photo detector mounted on said second universal joint assembly parallel to said central axis, said first photo detector and photo sensor for generating said first signal and said second photo detector and photo sensor for generating said second signal.

19. An assembly as set forth in claim 12 wherein said at least one sensor assembly is comprised of a first potentiometer mounted to said first drive axle for generating said first signal corresponding in magnitude to said first operational angle and a second potentiometer mounted to said second drive axle for generating said second signal corresponding in magnitude to said second operational angle.

20. An assembly as set forth in claim 19 wherein said first and second drive axles including mounting plates fixed to said first and second center differentials and said first and second potentiometers each include a first link mounted parallel to said mounting plates, a second link extending downwardly from one end of said first link, and a tube interconnecting said first and second links wherein said tube receives a spherical member that moves within said tube as said first and second differentials are tilted and wipes against potentiometer wiping elements to generate said first and second signals.

21. An assembly as set forth in claim 12 wherein said at least one sensor assembly is comprised of a first fluid sensor mounted to said first center differential and a second fluid sensor mounted to said second center differential, said first fluid sensor for generating said first signal corresponding in magnitude to said first operational angle based on a fluid level measured by said first fluid sensor and said second fluid sensor for generating said second signal corresponding in magnitude to said second operational angle based on a fluid level measured by said second fluid sensor.

22. An assembly as set forth in claim 21 including mounting plates fixed to said first and second center differentials and wherein said first and second fluid sensors each include a vertically extending sidewall that is mounted parallel to said respective mounting plate.

23. An assembly as set forth in claim 12 including a first mounting plate fixed to said first center differential and a second mounting plate fixed to said second center differential and wherein said at least one sensor assembly includes a first proximity coil mounted in a plane parallel to said first mounting plate, a first magnetic member suspended from said first center differential, a second proximity coil mounted in a plane parallel to said second mounting plate, and a second magnetic member suspended from said second center differential wherein said first signal is generated based on the separation distance between said first proximity coil and said first magnetic member and said second signal is generated based on the separation distance between said second proximity coil and said second magnetic member.

24. An assembly as set forth in claim 12 including a first mounting plate fixed to said first center differential and a second mounting plate fixed to said second center differential and wherein said at least one sensor assembly includes a first accelerometer mounted parallel to said first mounting plate and a second accelerometer mounted parallel to said second mounting plate, said first accelerometer for generating said first signal based on an acceleration due to gravity measurement at said first drive axle and said second accelerometer for generating said second signal based on a an acceleration due to gravity measurement at said second drive axle.