SHIFT RAIL TRANSMISSION POSITION SENSING WITH A MINIMUM NUMBER OF SENSORS

• US 20110035122A1
• Filed: 08/03/2010
• Published: 02/10/2011
• Est. Priority Date: 08/04/2009
• Status: Active Grant

• Current Assignee: Eaton Cummins Automated Transmission Technologies, LLC
• Original Assignee: Eaton Corp. (Wisconsin) (Eaton Corporation PLC.)
• Inventors: Katrak, Kerfegar K.
• Granted Patent: US 8,606,472 B2
• Time in Patent Office: Days
• US Class Current: 701/51
• CPC Class Codes: F16H 59/70 dependent on the ratio established
• CPC Class Codes: F16H 61/68 specially adapted for stepped gearings
• CPC Class Codes: G01B 7/30 for measuring angles or tapers; for testing the alignment of axes
• CPC Class Codes: Y10T 74/19251 Control mechanism

Abstract

A processing component configured to receive position sensor data from a first sensor attached to a shift rail of a transmission and determine from the first sensor data whether the shift rail is in a position of engagement of a first gear or a second gear or in a neutral position; receive position sensor data from a second sensor attached to the shift rail, determine from the second sensor data whether the shift rail is in a position of engagement of the first gear or the second gear or in the neutral position; compare the position determined from the first sensor data with the position determined from the second sensor data, and verify the shift rail position based on the comparison.

Further, a method for verifying shift rail position based on comparing data received from a first and a second sensor attached to the shift rail.

Claims

1. A control module, comprising:

a processing component configured to;

receive position sensor data from a first sensor attached to a shift rail of a transmission; and

determine from the first sensor data whether the shift rail is in a position of engagement of a first gear, a position of engagement of a second gear, or in a neutral position.

2. The control module of claim 1, the processing component further configured to:

receive position sensor data from a second sensor attached to the shift rail;

determine from the second sensor data whether the shift rail is in a position of engagement of the first gear, a position of engagement of the second gear, or in the neutral position;

compare the position determined from the first sensor data with the position determined from the second sensor data; and

verify the shift rail position based on the comparison.

3. The control module of claim 2, wherein the processing component is further configured to compare by identifying a time difference between a peak of the first sensor data and a peak of the second sensor data.

4. The control module of claim 2, wherein the processing component is further configured to compare by identifying one of a voltage or a current difference between the first sensor data and the second sensor data at a predetermined time.

5. The control module of claim 2, wherein the processing component is further configured to compare by identifying a phase difference between the first sensor data and the second sensor data.

6. The control module of claim 2, wherein the processing component is further configured to compare by correlating the first sensor data with the second sensor data in one of time domain or frequency domain.

7. The control module of claim 2, wherein the processing component is further configured to recognize an open circuit condition of the first sensor by comparing the first sensor data to the second sensor data.

8. The control module of claim 1,

wherein

the shift rail is one of a plurality of shift rails in a shift rail transmission;

the number of rails in the plurality of shift rails is equal to N;

one position sensor is attached to each shift rail; and

each sensor indicates whether the shift rail is in a position of engagement of the first gear, a position of engagement of the second gear, or in the neutral position, such that the N position sensors indicate three times N gear engagement positions.

9. The control module of claim 8, wherein there are four rails, and the four position sensors indicate twelve gear engagement positions.

10. The control module of claim 9, wherein the four rails and twelve gear engagement positions are:

a first rail with Reverse, Neutral and First/Second gear engagement positions;

a second rail with Third gear, Neutral, and Fifth gear engagement positions;

a third rail with Fourth gear, Neutral, and Sixth gear engagement positions; and

a fourth rail with Unlock and Lock engagement positions and a transition position between Unlock and Lock.

11. A method, comprising:

receiving position sensor data from a first sensor attached to a shift rail of a transmission; and

in a computing device, determining from the first sensor data whether the shift rail is in a position of engagement of a first gear, a position of engagement of a second gear, or in a neutral position.

12. The method of claim 11, further comprising:

receiving position sensor data from a second sensor attached to the shift rail;

determining from the second sensor data whether the shift rail is in a position of engagement of the first gear, a position of engagement of the second gear, or in the neutral position;

comparing the position determined from the first sensor data with the position determined from the second sensor data; and

verifying the shift rail position based on the comparison.

13. The method of claim 12, wherein the comparison is performed by identifying a time difference between a peak of the first sensor data and a peak of the second sensor data.

14. The method of claim 12, wherein the comparison is performed by identifying one of a voltage or a current difference between the first sensor data and the second sensor data at a predetermined time.

15. The method of claim 12, wherein the comparison is performed by identifying a phase difference between the first sensor data and the second sensor data.

16. The method of claim 12, wherein the comparison is performed by correlating the first sensor data with the second sensor data in one of time domain or frequency domain.

17. The method of claim 12, further comprising recognizing an open circuit condition of the first sensor by comparing the first sensor data to the second sensor data.

18. The method of claim 11,

wherein

the shift rail is one of a plurality of shift rails in a shift rail transmission;

the number of rails in the plurality of shift rails is equal to N;

one position sensor is attached to each shift rail; and

each sensor indicates whether the shift rail is in a position of engagement of the first gear, a position of engagement of the second gear, or in the neutral position, such that the N position sensors indicate three times N gear engagement positions.

19. The method of claim 18, with four rails, and the four position sensors indicating twelve gear engagement positions.

20. The method of claim 19, wherein the four rails and twelve gear engagement positions are:

a first rail with Reverse, Neutral and First/Second gear engagement positions;

a second rail with Third gear, Neutral, and Fifth gear engagement positions;

a third rail with Fourth gear, Neutral, and Sixth gear engagement positions; and

a fourth rail with Unlock and Lock engagement positions and a transition position between Unlock and Lock.