Sensor module

Abstract

A capacitive sensor module with a sensor electrode which is used to detect the entry of an object into a space ahead of the sensor electrode, wherein the sensor electrode is formed from a wire. Parallel to the sensor electrode, auxiliary electrodes extend within a plastic carrier that possesses recesses to receive the sensor electrode and the auxiliary electrodes and partially surrounds them along their circumference. The sensor electrodes can be pressed into the plastic carrier by overcoming an elastic forming force and are held within their recesses by the elastic reshaping process.

Description

BACKGROUND OF THE INVENTION[0001]The invention involves a sensor module for use in or on motor vehicles.[0002]The invention particularly involves a sensor module with a sensor electrode which will be used in order to prevent the entry of an object into a space ahead of the sensor electrode. At least one auxiliary electrode extends parallel to the sensor electrode.[0003]Such sensor arrays are used in vehicles within various fields.[0004]A capacitive sensor array with a sensor electrode with whose aid the approach of an object is to be detected, and with a control and evaluation circuit that is linked to the sensor electrode and detects a capacity change of the sensor electrode as compared to mass by periodically linking the sensor electrode with an operating voltage at a predetermined frequency and evaluating at least one parameter of a current or voltage progression that is dependent on the periodic charging and discharging of the sensor electrode in order to detect the capacity cha...

AI Technical Summary

Benefits of technology

[0013]The invention therefore provides a sensor module which allows the formation of a sensitive capacitive proximity sensor in a simple manner and from separate components. The sensor electrodes are pressed into the carrier material as cables or wires and kept at a defined distance from each other within it. Stable intervening spaces and orientation are ensured throughout the entire mounting distance with the carrier material in accordance with the invention. Due to the carrier forming process, it is possible to guide the sensor electrodes reproducibly and precisely within a desired arrangement and orientation towards each other.

[0014]The embodiment with separate components for the sensor electrodes on the one hand and the carrier material on the other hand allows very effective production. The carrier can be commonly produced by extrusion from a suitable plastic material, while the cables or wires are available mass wares. The individual components are easily combined with each other and also easily separated from each other again, which simplifies repair in case of defects.

[0019]In a further embodiment, at least one of the electrodes is formed from a mantled cable. It is fundamentally possible to form one or more of the electrodes from wires in order to influence the spread and detection of electrical fields to the lowest possible degree. However mantled cables are preferably used, due to the simplicity of handling, robustness and their insensitivity to environmental influences.

Problems solved by technology

The production and maintenance of such sensor arrays is difficult and costly.

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