Adjusting Clutch Slip Based on Sensed Parameter of Transmission Shaft to Control NVH Level in Vehicle Powertrain

• US 20140148304A1
• Filed: 11/27/2012
• Published: 05/29/2014
• Est. Priority Date: 11/27/2012
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Pietron, Gregory Michael, Fujii, Yuji, Yanakiev, Diana, Kucharski, Joseph F., Kapas, Nimrod, Gibson, Alexander O'Connor, Lee, Seung-Hoon
• Granted Patent: US 8,882,636 B2
• Time in Patent Office: Days
• US Class Current: 477/5
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/026 of lock-up clutches
• CPC Class Codes: B60W 10/11 Stepped gearings
• CPC Class Codes: B60W 2510/0241 Clutch slip, i.e. difference between input and output speeds
• CPC Class Codes: B60W 30/18 Propelling the vehicle

Abstract

A vehicle powertrain includes a transmission and a clutch. The slip of the clutch is adjusted to a target where a magnitude of a sensed parameter of a shaft of the transmission corresponds to a desired noise, vibration, and harshness (NVH) level in the powertrain. The sensed parameter of the transmission shaft may be one of acceleration, speed, and torque of the transmission shaft. The transmission shaft may be one of the input shaft and output shaft of the transmission.

Claims

1. A method for a powertrain having a transmission and a clutch, the method comprising:

adjusting slip of the clutch to a target in which a magnitude of a sensed parameter of a shaft of the transmission corresponds to a desired noise, vibration, and harshness (NVH) level in the powertrain.

2. The method of claim 1 further comprising:

obtaining an indication of the NVH level in the powertrain based on the magnitude of the sensed parameter of the transmission shaft.

3. The method of claim 2 wherein:

the indication of the NVH level in the powertrain is obtained from a database having a respective NVH level indication for each of a plurality of magnitudes of the parameter of the transmission shaft.

4. The method of claim 1 further comprising:

obtaining the target of the slip of the clutch from a database having a respective clutch slip target for each of a plurality of desired NVH levels.

5. The method of claim 1 wherein:

the sensed parameter of the transmission shaft is one of acceleration, speed, and torque of the transmission shaft.

6. The method of claim 1 wherein the transmission includes an input shaft and an output shaft, wherein:

the transmission shaft is one of the input shaft and the output shaft.

7. The method of claim 1 wherein:

the magnitude of the sensed parameter is one of peak-to-peak change, half peak-to-peak change, and root-mean-square value of the sensed parameter.

8. The method of claim 1 further comprising:

sensing the parameter of the transmission shaft as the slip of the clutch is adjusted to thereby provide a closed-loop control of the transmission shaft.

9. The method of claim 1 wherein:

the desired NVH level in the powertrain depends on an operating condition of the powertrain such that the target of the slip of the clutch varies based on the operating condition of the powertrain.

10. The method of claim 1 wherein:

the target of the slip of the clutch is subject to an upper limit and a lower limit.

11. A system for a powertrain having a transmission and a clutch, the system comprising:

a sensor for sensing a parameter of a shaft of the transmission; and

a controller in communication with the sensor and configured to adjust slip of the clutch to a target in which a magnitude of the sensed parameter of the transmission shaft corresponds to a desired noise, vibration, and harshness (NVH) level in the powertrain.

12. The system of claim 11 wherein:

the controller is further configured to obtain an indication of the NVH level in the powertrain based on the magnitude of the sensed parameter of the transmission shaft.

13. The system of claim 11 further comprising:

a database having a respective NVH level indication for each of a plurality of magnitudes of the parameter of the transmission shaft;

wherein the controller is further configured to obtain the indication of the NVH level in the powertrain from the database.

14. The system of claim 13 wherein:

the database further has a respective clutch slip target for each of a plurality of desired NVH levels;

wherein the controller is further configured to obtain the target of the slip of the clutch from the database.

15. The system of claim 11 wherein

the sensed parameter of the transmission shaft is one of acceleration, speed, and torque of the transmission shaft;

and

the magnitude of the sensed parameter of the transmission shaft is one of peak-to-peak change, half peak-to-peak change, and root-mean-square value of the sensed parameter of the transmission shaft.

16. The system of claim 11 wherein the transmission includes an input shaft and an output shaft and the clutch is connected to the input shaft of the transmission, wherein:

the transmission shaft is one of the input shaft and the output shaft.

17. A vehicle comprising:

a powertrain having a transmission and a clutch; and

a controller configured to adjust slip of the clutch to a target in which a magnitude of a sensed parameter of one of an input shaft and an output shaft of the transmission corresponds to a desired noise, vibration, and harshness (NVH) level in the powertrain.

18. The vehicle of claim 17 further comprising:

an engine;

wherein the clutch is connected between the engine and the input shaft of the transmission.

19. The vehicle of claim 17 wherein:

the clutch is one of a bypass clutch of a torque converter and an input clutch on a dual clutch arrangement.

20. The vehicle of claim 17 wherein:

the powertrain is a hybrid powertrain further having an engine and a motor connected to the transmission, wherein the clutch is one of a disconnect clutch connected between the engine and the motor and a bypass clutch connected to the input shaft of the transmission.