Capacitive sensor system

Patent metadata

Field	Value
Publication number	US-11099223-B2
Application number	US-201816757413-A
Country	US
Kind code	B2
Filing date	Oct 12, 2018
Priority date	Oct 19, 2017
Publication date	Aug 24, 2021
Grant date	Aug 24, 2021

Abstract

A capacitive sensor system that includes: a sensor arrangement with a plurality of capacitive electrodes, each being connected to a corresponding detector line; and a detector device connected to each detector line and configured to detect the capacitance of each electrode by applying a detector signal. The sensor arrangement includes: at least one electrode group having at least two electrodes, each electrode of an electrode group being connected to another electrode via a resistive element so that all electrodes of this electrode group are connected in series; and a diagnose device that is connected, for each electrode group, at least to a first detector line of a first electrode and to a second detector line of a second detector electrode and is configured to apply a diagnose signal via the first and second detector lines and to detect a conductor break based on a response to the diagnose signal.

First claim

The invention claimed is:

1. A capacitive sensor system, comprising:
a sensor arrangement with a plurality of capacitive electrodes, each being connected to a corresponding detector line; and
a detector device connected to each detector line and configured to detect the capacitance of each electrode by applying a detector signal;
wherein
the sensor arrangement comprises at least one electrode group comprising at least two electrodes, each electrode of an electrode group being connected to another electrode via a resistive element so that all electrodes of this electrode group are connected in series; and
a diagnose device is connected, for each electrode group, at least to a first detector line of a first electrode and to a second detector line of a second electrode and is configured to apply a diagnose signal via the first and second detector lines and to detect a conductor break based on a response to the diagnose signal.

2. A capacitive sensor system according to claim 1 , wherein the detector signal is an AC signal.

3. A capacitive sensor system according to claim 1 , wherein the diagnose signal is a DC signal.

4. A capacitive sensor system according to claim 1 , wherein the sensor arrangement is a printed foil sensor or a printed textile sensor.

5. A capacitive sensor system according to claim 1 , wherein the capacitive sensor system is adapted for hand detection on a steering wheel.

6. A capacitive sensor system according to claim 1 , wherein the sensor arrangement comprises a plurality of electrode groups, each comprising exactly two electrodes.

7. A capacitive sensor system according to claim 1 , wherein at least one electrode group comprises at least one intermediate electrode connected in series between the first and second electrode and connected to an intermediate detector line.

8. A capacitive sensor system according to claim 7 , wherein the sensor arrangement comprises a single electrode group.

9. A capacitive sensor system according to claim 7 , wherein the diagnose device is connected only to the first detector line and the second detector line.

10. A capacitive sensor system according to claim 7 , wherein the diagnose device is connected to at least one intermediate detector line.

11. A capacitive sensor system according to claim 10 , wherein the diagnose device is configured to sequentially apply a diagnose signal via each of a plurality of pairs of detector lines.

12. A capacitive sensor system according to claim 10 , wherein the diagnose device is configured to apply a diagnose current into said at least one detector line and to detect a voltage signal on said at least one detector line.

13. A capacitive sensor system according to claim 7 , wherein at least one intermediate detector line is connected to a connection line between an electrode and a resistive element.

14. A capacitive sensor system according to claim 1 , wherein the capacitive sensor system comprises at least one diagnose line connected to the diagnose device and to a connection line between an electrode and a resistive element.

15. A capacitive sensor system according to claim 14 , wherein the diagnose device is configured to apply a diagnose signal via the diagnose line and at least one detector line and to detect a conductor break based on a response to the diagnose signal.

16. A method for operating a capacitive sensor system which comprises:
a sensor arrangement with a plurality of capacitive electrodes, each being connected to a corresponding detector line; and
a detector device connected to each detector line and configured to detect the capacitance of each electrode by applying a detector signal;
wherein
the sensor arrangement comprises at least one electrode group comprising at least two electrodes, each electrode of an electrode group being connected to another electrode via a resistive element so that all electrodes of this electrode group are connected in series;
the method comprising, for each electrode group, applying a diagnose signal via a first detector line of a first electrode and a second detector line of a second electrode and detecting a conductor break based on a response to the diagnose signal.

17. A method for operating a capacitive sensor system according to claim 16 , wherein said capacitive sensor system further comprises at least one diagnose line connected to the diagnose device and to a connection line between an electrode and a resistive element, and wherein said method comprises the steps of applying a diagnose signal via the diagnose line and at least one detector line and detecting a conductor break based on a response to the diagnose signal.

Assignees

• Iee Sa

Inventors

• Lamesch Laurent
• Puetz Michael
• Wendt Christoph
• Favalli Gianluca

Classifications

• G01D5/24 Primary

  by varying capacitance · CPC title

• G01R27/2605 Primary

  Measuring capacitance (capacitive sensors G01D5/24) · CPC title

• G06F3/044

  by capacitive means · CPC title

• G01D2218/10

  Testing of sensors or measuring arrangements · CPC title

• G01D18/00

  Testing or calibrating apparatus or arrangements provided for in groups G01D1/00 - G01D15/00 · CPC title