Claims
- 1. A method of diagnosing a malfunction of a clutch actuator that actuates the engagement and disengagement of a clutch of a motor vehicle with a transmission and a control unit, comprising the steps of:
a) feeding an input command signal representing a desired amount of clutch engagement from the control unit to the clutch actuator; b) measuring the clutch-actuator position and generating an actual position signal corresponding to the actually measured clutch-actuator position; c) feeding the actual position signal to a processor unit for the function of the clutch and the dynamic behavior of the engine, which generates an actual rpm signal based on an rpm-sensor input, representing a measured engine rpm-rate; d) simultaneously with step c), feeding the actual position signal to a calculator unit which calculates a theoretically estimated engine rpm-rate based on the estimated position signal and a current engine torque and generates an estimated rpm signal representing the theoretically estimated engine rpm-rate; e) feeding the actual rpm signal and the estimated rpm signal to a comparator unit which, in turn, generates a comparison signal representing the result of a comparison of actual and estimated rpm signals; f) based on said comparison signal, making a conclusion about the condition of the clutch.
- 2. The method of claim 1, wherein the comparison signal is returned from the comparator unit through a feedback line to the calculator unit, so that the calculator unit can apply a correction to keep the actual rpm signal and the estimated rpm signal from drifting apart.
- 3. A method of diagnosing a malfunction of a clutch of a motor vehicle with a transmission, comprising the steps of:
a) by means of a first sensor, generating a first electrical signal, which indicates if the motor vehicle is standing still; b) by means of a second sensor, generating a second electrical signal, which indicates if a gear in the automatically shifting transmission cannot be synchronized within a prescribed time interval; c) by means of a third sensor, generating a third electrical signal, which indicates if the engine is running; d) evaluating the first, second and third electrical signals in a logic AND-member which sets an error flag indicating a malfunction in the clutch-actuator if all three signals are affirmative.
- 4. The method of claim 3, wherein the transmission is shifted into neutral when the error flag has been set.
- 5. The transmission of claim 3, wherein the error flag is canceled if a selector lever of the transmission is actuated by a driver of the motor vehicle before a prescribed time limit has elapsed after the error flag has been set.
- 6. An apparatus for automatically actuating a clutch with a clutch actuator, wherein the apparatus is adapted to perform the method of claim 1.
- 7. An apparatus for automatically actuating a clutch with a clutch actuator, wherein the apparatus is adapted to perform the method of claim 3.
Priority Claims (1)
Number |
Date |
Country |
Kind |
100 42 554.2 |
Aug 2000 |
DE |
|
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional application of copending U.S. patent application Ser. No. 09/943,409,filed Aug. 30, 2001 which is hereby incorporated by reference in its entirety.
Divisions (1)
|
Number |
Date |
Country |
Parent |
09943409 |
Aug 2001 |
US |
Child |
10375821 |
Feb 2003 |
US |