Patent ID: 7185939
Filing Date: 2007-03-06
Classification: F15B

Abstract:
1. A hydraulic drive system for a vehicle roof having at least one roof part that may be opened and closed and that may be adjusted via an actuator, the drive system comprising: a volumetric flow source that is connected to the actuator, wherein the position of the actuator is correlated to the particular position of the roof part over an actuating path, a volumetric flow sensor that detects the position of the roof part by a measuring system, wherein measured signals corresponding to the positions of the roof part are determined by reference to a plurality of set point values, a controller that controls the volumetric flow to the actuator over the actuating path of the actuator, wherein the volumetric flow is specified in terms of the plurality of set point values, and wherein the actual position of the roof part is monitored by the volumetric flow sensor and is provided as an actual value, wherein actual value of the volumetric flow is compared to the volumetric flow specified over the actuating path as the plurality of set point values, wherein a deviation of the actual value from the set point value is controlled to compensate for variations.