Method for non-microslip based dual clutch transmission power on up shift

Patent metadata

Field	Value
Publication number	US-10689001-B2
Application number	US-201816119698-A
Country	US
Kind code	B2
Filing date	Aug 31, 2018
Priority date	Jul 17, 2013
Publication date	Jun 23, 2020
Grant date	Jun 23, 2020

Abstract

A method of controlling a dual clutch transmission power on up shift including an on-coming clutch and an off-going clutch. The method includes implementing a prep phase comprised of decreasing torque on the off-going clutch, monitoring the off-going clutch speed to determine a slip point, and adding a bump torque to the off-going clutch when the off-going clutch reaches the slip point. The method implements a torque phase transferring torque from the off-going clutch to the on-coming clutch by increasing torque on the on-coming clutch towards an engine torque, decreasing torque on the off-going clutch, and simultaneously keeping the combination of torques greater than the slip point.

First claim

What is claimed is:

1. A method of controlling a dual clutch transmission power on up shift, including an on-coming clutch and an off-going clutch, comprising:
implementing a first phase that establishes an on-coming first phase torque of the on-coming clutch and an off-going first phase torque of the off-going clutch such that a first phase slippage between the on-coming clutch and the off-going clutch does not occur, wherein the first phase further comprises:
decreasing the off-going first phase torque on the off-going clutch;
determining a first phase slip point of the off-going clutch when the first phase slippage occurs; and
adding a bump torque to the off-going clutch when the off-going clutch begins to slip at the slip point, the bump torque preventing any further off-going slip;

implementing a second phase, after the first phase, wherein an on-coming second phase torque of the on-coming clutch is increased and an off-going second phase torque of the off-going clutch is simultaneously decreased such that a combination of the on-coming second phase torque of the on-coming clutch and the off-going second phase torque of the off-going clutch is greater than a second phase slip point, until the off-going second phase torque of the off-going clutch reaches a baseline off-going second phase torque of the off-going clutch; and
implementing a third phase, after the second phase, wherein a net negative torque is imparted to the engine by increasing an on-coming third phase torque of the on-coming clutch.

2. The method of claim 1 , wherein the net negative torque is imparted to the engine by increasing the on-coming third phase torque until the engine speed decreases and is in alignment with a speed of the on-coming clutch.

3. The method of claim 2 , wherein the third phase further includes decreasing an off-going third phase torque from the baseline second phase off-going torque to a final off-going third phase torque and during a disconnect period.

4. The method of claim 3 , wherein the disconnect period occurs when the net negative torque is imparted to the engine by increasing the on-coming third phase torque.

5. The method of claim 1 , wherein increasing the on-coming second phase torque comprises increasing the on-coming second phase torque towards an engine torque engagement point that is determined based on at least one of an engine torque, a feed-forward engine torque, and an engine flare feedback.

6. The method of claim 1 , wherein the first phase further comprises increasing the on-coming first phase torque to a pre-fill torque, wherein the pre-fill torque comprises a plate-touch-point torque that is a torque transmitted when clutch plates come into an initial contact.

7. A dual clutch transmission comprising:
a first clutch;
a second clutch;
a clutch control assembly in communication with the first clutch and the second clutch, the clutch control assembly configured to power on up shift by:
implementing a first phase that establishes an on-coming first phase torque of the second clutch and an off-going first phase torque of the first clutch such that a first phase slippage between the second clutch and the first clutch does not occur, wherein the first phase further comprises:
decreasing the on-coming first phase torque on the first clutch;
determining a first phase slip point of the first clutch when the first phase slippage occurs; and
adding a bump torque to the first clutch when the first clutch begins to slip at the first phase slip point, the bump torque preventing any further slip;

implementing a second phase, after the first phase, wherein an on-coming second phase torque of the second clutch is increased and an off-going second phase torque of the first clutch is simultaneously decreased such that a combination of the off-going second phase torque of the first clutch and the on-coming second phase torque of the second clutch is greater than a slip point, until the off-going second phase torque of the first clutch reaches a baseline off-going second phase torque; and
implementing a third phase, after the second phase, wherein a net negative torque is imparted to the engine by increasing an on-coming third phase torque of the second clutch.

8. The dual clutch transmission of claim 7 , wherein the net negative torque is imparted to the engine by increasing the on-coming third torque until the engine speed decreases and is in alignment with a speed of the on-coming clutch.

9. The dual clutch transmission of claim 8 , wherein the third phase further includes decreasing an off-going third phase torque from the baseline off-going second phase torque to a final off-going third phase torque and during a disconnect period.

10. The dual clutch transmission of claim 9 , wherein the disconnect period occurs when the net negative torque is imparted to the engine by increasing the on-coming third phase torque.

11. The dual clutch transmission of claim 7 , wherein increasing the on-coming second phase torque comprises increasing the on-coming second phase torque towards an engine torque engagement point that is determined based on at least one of an engine torque, a feed-forward engine torque, and an engine flare feedback.

12. The dual clutch transmission of claim 7 , wherein the first phase further comprises increasing torque on the second clutch to a pre-fill torque, wherein the pre-fill torque comprises a plate-touch-point torque that is a torque transmitted when clutch plates come into an initial contact.

13. A system for operating a dual clutch transmission, including a clutch control assembly configured to:
implement a first phase that establishes an on-coming torque and an off-going torque such that a slippage between the on-coming clutch and the off-going clutch does not occur, wherein the clutch control assembly is further configured to implement the first phase by being configured to:
decrease the off-going torque on the off-going clutch;
determine a first phase slip point of the off-going clutch when the slippage occurs; and
add a bump torque to the off-going clutch when the off-going clutch begins to slip at the first phase slip point, the bump torque preventing any further slip;

implement a second phase, after the first phase, wherein the on-coming torque is increased and the off-going torque is simultaneously decreased such that a combination of the two torques is greater than a second phase slip point, until the off-going torque reaches a baseline off-going torque; and
implement a third phase, after the second phase, wherein a net negative torque is imparted to the engine by increasing the on-coming torque.

14. The system of claim 13 , wherein clutch control assembly configured to impart the net negative torque to the engine by increasing the on-coming torque until the engine speed decreases and is in alignment with a speed of the on-coming clutch.

15. The system of claim 14 , wherein the clutch control assembly is further configured to implement the third phase by being configured to decrease the off-going torque from the baseline off-going torque to a final off-going torque and during a disconnect period, and wherein the disconnect period occurs when the net negative torque is imparted to the engine by increasing the on-coming torque.

16. The system of claim 13 , wherein the clutch control assembly is configured to increase torque on the on-coming clutch during the second phase by increasing torque on the on-coming clutch towards an engine torque engagement point that is determined based on at least one of an engine torque, a feed-forward engine torque, and an e

Assignees

• Eaton Cummins Automated Trans Tech Llc

Inventors

• Dunfee Ii Jeffrey S
• Hart Andrew
• Fitzgerald Simon
• Gallion Michael

Classifications

• B60W10/113 Primary

  with two input flow paths, e.g. double clutch transmission selection of one of the torque flow paths by the corresponding input clutch · CPC title

• B60W2510/0657

  Engine torque · CPC title

• B60W10/02

  including control of driveline clutches · CPC title

• B60W30/18

  Propelling the vehicle · CPC title

• F16D2500/30406

  Clutch slip · CPC title