Dynamic control system for continuously variable transmission

• US 8,352,138 B2
• Filed: 11/30/2007
• Issued: 01/08/2013
• Est. Priority Date: 11/30/2007
• Status: Active Grant

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Dahl, Kristofor Lee, Ingram, Richard George, Spielman, Michael Anthony Jr., Martinez, Alberto Jr., Zhao, Yaang, Hoffman, Ellen Jean
• Primary Examiner(s): Chen, Shelley
• Application Number:
  US11/987,520
• Publication Number:
  US 20090143948A1
• Time in Patent Office: 1,866 Days
• Field of Search: 701/56
• US Class Current: 701/56
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/101 Infinitely variable gearings
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2540/12 Brake pedal position
• CPC Class Codes: B60W 30/182 Selecting between different operative modes, e.g. comfort and performance modes
• CPC Class Codes: B60W 30/188 Controlling power parameters of the driveline, e.g. determining the required power
• CPC Class Codes: B60Y 2200/415 Wheel loaders
• CPC Class Codes: F16H 2061/0227 Shift map selection, i.e. methods for controlling selection between different shift maps, e.g. to initiate switch to a map for up-hill driving
• CPC Class Codes: F16H 2061/6643 dependent on driver's choice
• CPC Class Codes: F16H 59/18 dependent on the position of the accelerator pedal
• CPC Class Codes: F16H 59/54 dependent on signals from the brakes, e.g. parking brakes
• CPC Class Codes: F16H 61/472 for achieving a target output torque
• CPC Class Codes: F16H 61/662 with endless flexible members
• CPC Class Codes: F16H 61/664 Friction gearings

Abstract

A continuously variable transmission is provided having a driven element. The continuously variable transmission also has a first operator input device configured to transmit a first displacement signal corresponding to a displacement of the first operator input device. The continuously variable transmission further has a second operator input device configured to transmit a second displacement signal corresponding to a displacement of the second operator input device. In addition, the continuously variable transmission has a third operator input device configured to transmit a transmission operating mode request. Furthermore, the continuously variable transmission has at least one sensor configured to sense at least one parameter indicative of an operating condition of the transmission. Additionally, the continuously variable transmission has a controller configured to determine a driven element output request based on the operating request mode, the first displacement signal, the second displacement signal, and the at least one sensed parameter. The controller is also configured to regulate an output of the driven element in response to the operating mode request, the driven element output request, and the at least one sensed parameter.

Claims

1. A continuously variable transmission, comprising:

a driven element;

a first operator input device configured to transmit a first displacement signal corresponding to a displacement of the first operator input device;

a second operator input device configured to transmit a second displacement signal corresponding to a displacement of the second operator input device;

a third operator input device configured to transmit a transmission operating mode request;

at least one sensor configured to sense at least one parameter indicative of an operating condition of the transmission; and

a controller configured to;

determine a driven element output request based on the operating request mode, the first displacement signal, the second displacement signal, and the at least one sensed parameter;

regulate an output of the driven element in response to the operating mode request, the driven element output request, and the at least one sensed parameter; and

generate a net displacement value based on the operating mode request and one of a plurality of relationships between the displacement of the first operator input device and the displacement of the second operator input device.

2. The continuously variable transmission of claim 1, wherein the controller includes a plurality of base maps stored in the memory thereof, each base map being related to an operating mode of the transmission.

3. The continuously variable transmission of claim 2, wherein the controller is configured to select a base map in response to the transmission mode request.

4. The continuously variable transmission of claim 3, wherein each base map includes a plurality of sub-maps.

5. The continuously variable transmission of claim 4, wherein the controller is configured to select a sub-map in response to the driven element output request and the at least one sensed parameter indicative of an operating condition of the transmission.

6. The continuously variable transmission of claim 5, wherein the controller is configured to generate the net displacement value based on one of the plurality of sub-maps and the one of the plurality of relationships between the displacement of the first operator input device and the displacement of the second operator input device.

7. The continuously variable transmission of claim 6, wherein each of the relationships between the displacement of the first operator input device and the displacement of the second operator input device is associated with one or more sub-maps.

8. The continuously variable transmission of claim 7, wherein the controller is configured to generate a driven element output request based on the net displacement value.

9. The continuously variable transmission of claim 8, wherein each sub-map includes at least one limitation curve limiting the driven element output, and the controller is configured to modify each limitation curve based on the net displacement value.

10. A method of operating a transmission, comprising:

receiving an operating mode request;

receiving a first operator input device displacement signal;

receiving a second operator input device displacement signal;

sensing at least one parameter indicative of an operating condition of the transmission;

determining a transmission output request in response to the operating mode request, the first operator input device displacement signal, the second operator input device displacement signal, and the at least one parameter;

controlling an output of the transmission in response to the operating mode request, the determined transmission output request, and the at least one parameter; and

generating a net displacement value based on the operating mode request and one of a plurality of relationships between the first operator input device displacement signal and the second operator input device displacement signal.

11. The method of claim 10, further including determining the transmission output request based on the net displacement value.

12. The method of claim 11, further including limiting the transmission output based on the net displacement value.

13. A machine, comprising:

a power source configured to generate a power output;

at least one traction device configured to propel the machine;

an operator station configured to receive input from an operator indicative of a desired machine movement; and

a continuously variable transmission, including;

a driven element;

a first operator input device configured to transmit a first displacement signal corresponding to a displacement of the first operator input device;

a second operator input device configured to transmit a second displacement signal corresponding to a displacement of the second operator input device;

a third operator input device configured to transmit a transmission operating mode request;

at least one sensor configured to sense at least one parameter indicative of an operating condition of the transmission; and

a controller configured to;

determine a driven element output request based on the operating request mode, the first displacement signal, the second displacement signal, and the at least one sensed parameter;

regulate an output of the driven element in response to the operating mode request, the driven element output request, and the at least one sensed parameter; and

generate a net displacement value based on the operating mode request and one of a plurality of relationships between the displacement of the first operator input device and the displacement of the second operator input device.

14. The machine of claim 13, wherein the controller includes a plurality of base maps stored in the memory thereof, each base map being related to an operating mode of the transmission and including a plurality of sub-maps.

15. The machine of claim 14, wherein the controller is configured to select a base map in response to the transmission mode request and select a sub-map in response to the driven element output request and the at least one sensed parameter indicative of an operating condition of the transmission.

16. The machine of claim 15, wherein the controller is configured to generate the net displacement value based on one of the plurality of sub-maps and the one of the plurality of relationships between the displacement of the first operator input device and the displacement of the second operator input device.

17. The machine of claim 16, wherein each of the relationships between the displacement of the first operator input device and the displacement of the second operator input device is associated with one or more sub-maps.

18. The machine of claim 17, wherein the controller is configured to generate a driven element output request based on the net displacement value.

19. The machine of claim 18, wherein each sub-map includes at least one limitation curve limiting the driven element output, and the controller is configured to modify each limitation curve based on the net displacement value.