Patent ID: 6486631
Filing Date: 2002-11-26
Classification: G05B

Abstract:
A drive system for a covering device of a motor vehicle, the covering device being movable back and forth between a first end position and a second end position, the drive system comprising:an electric motor for controlled movement of the covering device between the first and second end positions; a current sensor for detecting current of the electric motor; a control device for the electric motor, having a first input for receiving a control signal which causes the control device to put the electric motor into operation to move the covering device from the first end position to the second end position, a second input connected to the current sensor for receiving a current signal, and an output through which the electric motor controlled, the control device being programmed to measure a value of at least one current parameter when the electric motor moves the covering device to leave the first end position, store the measured value of the current parameter as a reference value, continuously compare the reference value with later detected values of the current parameter, and switch the current for the electric motor off when a predetermined relative relationship between a later detected value of the current parameter and the reference value is met.