Capacitive automatic reversing device and method for operating automatic reversing device

Abstract

A capacitive anti-pinch means with a first electrode (2) and a second electrode (3), wherein the first electrode (2) and the second electrode (3) form the electrodes of one sensor, is, as regards a measurement which is independent of a ground potential (M1), characterized in that the first electrode (2) can be fed a first potential (Uref+), in that the second electrode (3) can be fed a second potential (Uref-), wherein the second potential (Uref-) is different from the first potential (Uref+), and in that said means are equipped with evaluation electronics (5) which determine the difference between the first potential (Uref+) and the second potential (Uref-) and determine the capacitance (CSensor) of the sensor from said difference. A corresponding method for operating the anti-pinch means is disclosed.

Description

technical field [0001] The invention relates to a capacitive autoreverse having a first electrode and a second electrode forming the electrodes of a sensor. The invention also relates to a method of operation of a corresponding automatic reversing device. Background technique [0002] Automatic reversing devices and methods for use on doors, hatches, sunroofs, convertible tops and the like are well known in practice. Optical, contact and capacitive methods are mainly used here. For industrial applications, take DE 40 06 119 A1 and EP 1 474 582 A1 as examples; for automotive applications, take DE 43 29 535 A1, DE 103 10 066 B3, DE 197 20 713 C1, DE 199 13 879 C1, DE 102 20 725 C1, DE 103 05 342 B4 and EP 1 154 110 B1 as examples. [0003] In contact automatic reversing devices, it is critical to detect obstacles in direct contact between the sensor and the object to be recognized. Types with one or two conductors are already known. For example, the sensor described in EP...

AI Technical Summary

Problems solved by technology

A long-standing problem with contact automatic reversing devices is that, in principle, contact must occur

[0005] The disadvantage of the known method with two electrodes is that the ground is not clearly defined in all parts that are not firmly connected to ground

For vehicles, for example, the ground wire can have a potential difference of several volts, depending on the installation location, which can lead to serious measurement errors

Therefore, a definitive electrical connection to the body cannot be guaranteed in the doors or tailgate, where contact is reduced by lubricants in the door hinges or corrosion of the metal surfaces

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