Capacitive positioning device

摘要

A positioning device for capacitively detecting an object enclosed in a medium includes a measuring electrode, a receiving electrode, and a reference capacitance. The measuring electrode and the receiving electrode form a measuring capacitance that can be influenced by the object and the reference capacitance cannot be influenced by the object. The electrodes are disposed in a plane, and the device includes a spacer that is configured to keep the electrodes at a predetermined minimum distance from the surface of the medium. The predetermined minimum distance is different from zero.

主权项

1. A locating appliance for the capacitive detection of an object enclosed in a medium, comprising:
a measurement electrode arranged in a plane with a reception electrode, the measurement electrode and the reception electrode configured to form a measurement capacitance that is influenced by the object; a reference electrode, the reference electrode and the reception electrode configured to form a reference capacitance that is not influenced by the object; an evaluation circuit configured to provide an output signal on the basis the measurement capacitance and the reference capacitance; and a spacer configured to hold the measurement electrode and the reception electrode at a predetermined minimum distance, other than zero, from the surface of the medium, the predetermined minimum distance being a distance at which the output signal is at one of a minimum and a maximum, independent of whether the object is present, wherein the measurement electrode, the reception electrode, and the reference electrode are arranged in common plane.