Patent ID: 7046129

Claim:
A device for detecting an obstacle in the opening range of a movable closure element, more particularly an electrically powered window pane or sunroof of a motor vehicle, comprising a sensor electrode having a first end and a second end, a base electrode having a first end and a second end and being spaced away from said sensor electrode, and a control unit connected to the first end of said sensor electrode and the first end of said base electrode, said sensor electrode and said base electrode generating an electric field in the opening range of said closure element and are spaced away from each other at a constant distance in a first operational mode, and said control unit in the first operational mode detecting a change in capacitance caused by the presence of an obstacle in said electric field and providing a control signal for a drive powering said closure element, said sensor electrode and said base electrode being connected together at the second end by an electronic component, a testing voltage being applied to said sensor electrode and said base electrode which, in a second operational mode, have a changeable distance to each other, and the control unit providing in the second operational mode a control signal for said drive powering said closure element when said sensor electrode comes into electrical contact with said base electrode.