Clutch torque trajectory correction to provide torque hole filling during a ratio upshift

• US 8,636,613 B2
• Filed: 12/19/2011
• Issued: 01/28/2014
• Est. Priority Date: 12/19/2011
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Teslak, Christopher John, Pietron, Gregory Michael, Tseng, Hongtei Eric, Fujii, Yuji, Fodor, Michael Glenn, Yanakiev, Diana, Lee, Seung-Hoon
• Primary Examiner(s): YOUNG, EDWIN
• Application Number:
  US13/330,120
• Publication Number:
  US 20130153353A1
• Time in Patent Office: 771 Days
• Field of Search: 475/125, 475/127, 475/266
• US Class Current: 475/125
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/11 Stepped gearings
• CPC Class Codes: F16H 2059/147 Transmission input torque, e.g. measured or estimated engine torque
• CPC Class Codes: F16H 2059/148 Transmission output torque, e.g. measured or estimated torque at output drive shaft
• CPC Class Codes: F16H 59/14 Inputs being a function of torque or torque demand
• CPC Class Codes: F16H 59/16 Dynamometric measurement of torque
• CPC Class Codes: F16H 59/70 dependent on the ratio established
• CPC Class Codes: F16H 61/04 Smoothing ratio shift
• CPC Class Codes: F16H 61/06 by controlling rate of change of fluid pressure
• CPC Class Codes: F16H 61/686 with orbital gears

Abstract

A multiple ratio transmission having an input shaft, an output shaft and oncoming clutch and off-going clutch for effecting ratio upshifts is provided. The transmission also includes a transmission controller configured for controlling shifts. During the torque phase of a ratio upshift, the controller increases input torque. Next, the controller estimates an oncoming clutch target torque. The controller controls a torque input to ensure the off-going clutch remains locked. The controller measures an actual transmission value for a torque transmitting element of the transmission and corrects the oncoming clutch target torque using the actual transmission value whereby an increasing torque for the oncoming friction element is achieved with minimal torque transients along the output shaft during the upshift.

Claims

1. A transmission comprising:

an input shaft;

an output shaft;

a first and second clutch actuated during an upshift between discrete gear ratios, wherein the first clutch is locked during a torque phase of the upshift; and

an actuator that modulates torque capacity of the second clutch during the torque phase in response to a measured torque of one of the input shaft and the output shaft.

2. The transmission of claim 1 further comprising a planetary gear system.

3. The transmission of claim 1 further comprising:

a torque sensor positioned to measure torque carried by one of the input shaft and the output shaft and providing a measured torque signal.

4. The transmission of claim 3 further comprising a second torque sensor positioned to measure torque carried by the other one of the input shaft and the output shaft.

5. The transmission of claim 4 wherein the first torque sensor provides the measured torque of the input shaft and the second torque sensor provides the measured torque of the output shaft.

6. The transmission of claim 5 wherein an actual torque value of one of the first and second clutch is determined by a difference between the measured torque of the input shaft and a calculated torque value of one of the first clutch and the second clutch, wherein the calculated torque value is determined from the measured torque of one of the input shaft and the output shaft.

7. The transmission of claim 1 wherein the actuator modulates the torque capacity of the second clutch to provide a substantially linearly decreasing torque of the output shaft during the torque phase and an inertia phase of the upshift.

8. A multiple ratio transmission comprising:

an input shaft;

an output shaft;

an oncoming clutch and off-going clutch for effecting a ratio upshift between discrete gear ratios; and

a shift controller configured for;

estimating a target torque for the oncoming clutch during a torque phase of the upshift;

controlling applying pressure of the off-going clutch so that the off-going clutch remains locked during the torque phase of the upshift;

adjusting the target torque of the oncoming clutch using a measured torque of a torque transmitting element of the transmission; and

controlling applying pressure of the oncoming clutch after adjusting.

9. The transmission of claim 8 further comprising a planetary gear system disposed between the input shaft and the output shaft.

10. The transmission of claim 8 wherein the transmission further comprises:

a first torque sensor positioned to measure torque carried by one of the input shaft and the output shaft and providing a corresponding measured torque signal.

11. The transmission of claim 10 further comprising a second torque sensor, the second torque sensor positioned to measure torque carried by the other one of the input shaft and the output shaft.

12. The transmission of claim 11 wherein the first torque sensor measures a sum of torque input for each of the oncoming clutch and the off-going clutch;

and

the second torque sensor is positioned to measure torque output of one of the oncoming and the off-going clutch, where torque output of the other of the oncoming and off-going clutch is equal to a difference between the torque measured by the first torque sensor and the torque measured by the second torque sensor.

13. The transmission of claim 11 wherein the first torque sensor provides a measured torque signal of the input shaft and the second torque sensor provides a measured torque signal of the output shaft.

14. The transmission of claim 8 wherein the shift controller further calculates an actual torque value of one of the oncoming clutch and the off-going clutch by calculating a difference between the measured input shaft torque and a calculated torque value of one of the oncoming clutch and the off-going clutch.

15. A method for controlling a transmission during an upshift, the method comprising:

controlling an off-going clutch to remain locked during a torque phase of the upshift;

measuring an actual torque for a torque transmitting element of the transmission; and

controlling an oncoming clutch torque capacity in response to the actual torque of the torque transmitting element to provide a generally decreasing output shaft torque during the torque phase and inertia phase of the upshift.

16. The method of claim 15 further comprising calculating a feedback torque of the oncoming clutch in response to the actual torque of the torque transmitting element, wherein the oncoming clutch is controlled based on the feedback torque.

17. The method of claim 16 wherein measuring the actual torque comprises measuring an actual torque of at least one of a transmission input shaft and a transmission output shaft.

18. The method of claim 15 further comprising increasing input torque to the transmission during the torque phase.

19. The method of claim 18 further comprising decreasing input torque to the transmission during a first portion of an inertia phase of the upshift and increasing input torque to the transmission during a second portion of the inertia phase of the upshift.

20. The method of claim 15 wherein controlling the oncoming clutch torque capacity comprises:

adjusting an estimated oncoming clutch target torque using the actual torque of the torque transmitting element.