Method for establishing malfunctions of components of a motor vehicle power train

• US 20060154783A1
• Filed: 01/09/2006
• Published: 07/13/2006
• Est. Priority Date: 01/13/2005
• Status: Active Grant

• Current Assignee: ZF Friedrichshafen AG (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: ZF Friedrichshafen AG (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Petzold, Rainer, Steinborn, Mario, Wolfgang, Werner, Jager, Thomas, Kramer, Rupert, Bitzer, Franz
• Granted Patent: US 7,635,317 B2
• Time in Patent Office: Days
• US Class Current: 477/107
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/10 including control of change-speed gearings
• CPC Class Codes: B60W 50/029 Adapting to failures or work around with other constraints, e.g. circumvention by avoiding use of failed parts
• CPC Class Codes: B60W 50/14 Means for informing the driver, warning the driver or prompting a driver intervention
• CPC Class Codes: F16H 59/16 Dynamometric measurement of torque
• CPC Class Codes: Y10S 477/906 Means detecting or ameliorating the effects of malfunction or potential malfunction

Abstract

A method for establishing malfunctions of components of a motor vehicle power train as well as the reaction to the same. The power train has a drive motor and an automatic transmission with respectively allocated control devices, setting apparatus and sensors, and the transmission input shaft is allocated a torque sensor for recording the transmission input shaft. During operation of the motor vehicle, the functions of the control devices, the operating elements, the sensors and their data transmission apparatus as well as the measured values of the transmission input torque are recorded and checked for signs of malfunction. After recognizing such a malfunction, operations are conducted by means of which the motor vehicle can be further operated in an emergency type of operation or with the aid of which the driving operation can be safely ended.

Claims

1-9. -9. (canceled)

10. A method for determining a malfunction of a component of a motor vehicle power train as well as a response to the malfunction, the power train having a drive motor and an automatic transmission with respectively allocated control devices, a setting apparatus and sensors, and a transmission input shaft having a torque sensor for recording the transmission input torque, the method comprising the steps of:

recording, during the operation of the motor vehicle, the function of the control devices, operating elements, the sensors and sensor data transmission apparatus as well as measured values of the transmission input torque;

checking the function of the control devices, the operating elements, the sensors and the sensor data transmission apparatus as well as the measured values of the transmission input torque for signs of malfunction;

undertaking operation, if a malfunction is recognized, by means of which the motor vehicle can be safely operated further in an emergency type of operation or with aid of which a travel operation can be safely ended.

11. The method according to claim 10, further comprising the step of communicating the measured transmission input torque to the motor control device and checking the measured transmission input torque for one or more of plausibility and correctness.

12. The method according to claim 11, further comprising the step of comparing the measured transmission input torque with a calculated motor torque, and activating, in an event of excessively high deviations between the measured transmission input torque and the calculated motor torque, an emergency type operation for one or more of the automatic transmission, other power train components and the motor vehicle devices.

13. The method according to claim 12, further comprising the step of deciding upon an interruption of fuel supply to the motor vehicle drive motor, on the basis of the comparison of the measured transmission input torque with the calculated motor torque or by an analysis of the measured course of torque on the transmission input shaft.

14. The method according to claim 13, further comprising the step of emitting a control signal from the transmission control device, after establishing the interruption of fuel supply, to other control devices in the power train so that the control signal can activate an emergency driving strategy for the interruption of fuel supply.

15. The method according to claim 13, further comprising the step of preventing gear ratio changes in the transmission with the transmission control device, after establishing the interruption of fuel supply, until the malfunction is eliminated.

16. The method according to claim 13, further comprising the step of issuing a control signal from one of the motor control device or a motor vehicle master computer, after establishing the interruption of fuel supply, to the transmission control device which prevents gear ratio change procedures of the automatic transmission until the malfunction is eliminated.

17. The method according to claim 10, further comprising the step of

operating one or more of elements and sensors from the course of signals of the torque sensor on the transmission input shaft after recognizing a malfunction in a data transmission link of the control devices;

recognizing an intention to shift (for example, down shift) by the driver signaled by the retraction of the accelerator deflection;

introducing a shifting of the transmission by opening a clutch and disengaging a current transmission gear ratio as well as subsequent closing of the clutch, subsequently a desired motor rotational speed or transmission input rotational speed for a new lower gear at a current speed of travel signaled by the renewed accelerator deflection and finally engaging the new gear.

18. The method according to claim 17, further comprising the step of communicating the malfunction optically and acoustically to the driver.