Shifting Virtual Gears Associated with a Continuously Variable Transmission

• US 20140121918A1
• Filed: 11/01/2012
• Published: 05/01/2014
• Est. Priority Date: 11/01/2012
• Status: Active Grant

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Davis, Kevin, Nackers, Adam, Beyer, Michael D., McBride, Shane C.
• Granted Patent: US 8,874,332 B2
• Time in Patent Office: Days
• US Class Current: 701/55
• CPC Class Codes: B60K 6/54 Transmission for changing ratio
• CPC Class Codes: B60K 6/543 the transmission being a continuously variable transmission
• CPC Class Codes: B60W 10/103 of fluid type
• CPC Class Codes: B60W 10/11 Stepped gearings
• CPC Class Codes: B60W 10/111 with separate change-speed gear trains arranged in series
• CPC Class Codes: B60W 30/1882 characterised by the working point of the engine, e.g. by using engine output chart
• CPC Class Codes: B60Y 2200/411 Bulldozers, Graders
• CPC Class Codes: F16H 47/04 the mechanical gearing being of the type with members having orbital motion
• CPC Class Codes: F16H 61/66 specially adapted for continuously variable gearings control of exclusively fluid gearing F16H61/38
• CPC Class Codes: Y10S 903/909 Gearing
• CPC Class Codes: Y10S 903/91 Orbital, e.g. planetary gears
• CPC Class Codes: Y10S 903/911 with two or more gear sets
• CPC Class Codes: Y10S 903/915 Specific drive or transmission adapted for hev
• CPC Class Codes: Y10S 903/917 with transmission for changing gear ratio
• CPC Class Codes: Y10S 903/945 Characterized by control of gearing, e.g. control of transmission ratio

Abstract

A system and method involves a machine having a power train including a continuously variable transmission (CVT) associated with a plurality of virtual gear ratios. To shift between the plurality of virtual gear ratios, the machine may include an operator input device that may be movable between a plurality of distinct positions. A first position may be associated with a neutral position in which no shifting of virtual gear ratios occurs. A second position of the operator input device may be associated with a first incremental rate for shifting between the virtual gear ratios. A third position may be associated with a second incremental rate for shifting between the virtual gear ratios which is different than the first incremental rate.

Claims

1. A method of regulating speed output of a machine having a continuously variable transmission (CVT), the CVT associated with a plurality of virtual gear ratios;

the method comprising;

registering movement of an operator input device from a first position to a second position;

shifting between virtual gears ratios from among a plurality of virtual gears ratios at a first incremental rate;

registering movement of the operator input device from the second position to a third position; and

shifting between virtual gear ratios from among the plurality of virtual gear ratios at a second incremental rate.

2. The method according to claim 1, wherein the first incremental rate is less than the second incremental rate.

3. The method according to claim 2, wherein the plurality of virtual gear ratios include integers of virtual gear ratios and fractions of virtual gear ratios.

4. The method according to claim 3, wherein the first incremental rate shifts between fractions of virtual gear ratios.

5. The method according to claim 4, wherein shifting at the first incremental rate terminates at a next integer of a virtual gear ratio.

6. The method according to claim 3, wherein the second incremental rate shifts to a next integer of a virtual gear ratio.

7. The method according to claim 6, wherein the second incremental rate terminates until movement of the operator input device to the first position is registered.

8. The method according to claim 1, further comprising:

registering movement of the operator input device to a fourth position;

shifting between virtual gear ratios at a first decremental rate;

registering movement of the operator input device to a fifth position; and

shifting between virtual gear ratios at a second decremental rate.

9. The method according to claim 1, wherein the operator input device is a slider switch.

10. A machine comprising:

a continuously variable transmission (CVT);

an operator input device movable between a plurality of positions;

a controller in communication with the operator input device, the controller configured to control the CVT in accordance with a plurality of virtual gear ratios;

wherein the controller associates a first position of the operator input device with a neutral position;

associates a second position of the operator input device with a first incremental rate for incrementing the plurality of virtual gear ratios; and

associates a third position of the operator input device with a second incremental rate for incrementing the plurality of virtual gear ratios.

11. The machine according to claim 10, wherein the first incremental rate is less than the second incremental rate.

12. The machine according to claim 11, wherein the plurality of virtual gear ratios include integers of virtual gear ratios and fractions of virtual gear ratios.

13. The machine according to claim 12, wherein the first incremental rate shifts between fractions of gear ratios.

14. The machine according to claim 13, wherein shifting at the first incremental rate terminates at a next integer of a virtual gear ratio.

15. The machine according to claims 12, wherein the second incremental rate shifts to a next integer of a virtual gear ratio.

16. The machine according to claim 15, wherein the second incremental rate terminates until movement of the operator input device to the first position is registered.

17. The machine of claim 10, wherein operator input device is a slider switch.

18. A method of regulating a continuously variable transmission (CVT) associated with a plurality of virtual gear ratios;

the method comprising;

selecting a virtual gear ratio from the plurality of virtual gear ratios;

registering a first operator input signal from an operator input device;

increasing the virtual gear ratio selected at a first rate;

registering a second operator input signal from the operator input device; and

increasing the virtual gear ratio selected at a second rate.

19. The method of claim 18, wherein the first rate is less than the second rate.

20. The method of claim 19, wherein the plurality of virtual gear ratios includes integers and fractions of virtual gear ratios.