Composite yarn for the position sensitive capacitive touch sensing

Patent metadata

Field	Value
Publication number	US-10754486-B2
Application number	US-201916412866-A
Country	US
Kind code	B2
Filing date	May 15, 2019
Priority date	May 16, 2018
Publication date	Aug 25, 2020
Grant date	Aug 25, 2020

Abstract

It is disclosed a composite yarn (1) comprising an electrically conductive yarn (2) and an electrically resistive yarn (3), wherein said electrically conductive yarn (2) is coupled to said electrically resistive yarn (3), and wherein the electrically conductive yarn (2) is electrically insulated from the electrically resistive yarn (3). It is further disclosed a touch sensor (10) comprising at least one composite yarn (1) according to anyone of the previous claims, and a detection device (5) configured to evaluate the capacitance values (CR, CC) of the electrically resistive yarn (3) and of the electrically conductive yarn (2) of said composite yarn (1), said detection device (5) being configured to calculate the ratio (CR/CC) between said capacitance values (CR, CC) of the electrically resistive yarn (3) and of the electrically conductive yarn (2) and to provide an output signal (SOUT) indicative of the location of a touch event along said composite yarn (1) in function of said ratio (CR/CC).

First claim

The invention claimed is:

1. A composite yarn ( 1 ) comprising an electrically conductive yarn ( 2 ) and an electrically resistive yarn ( 3 ), wherein said electrically conductive yarn ( 2 ) is coupled to said electrically resistive yarn ( 3 ), and wherein the electrically conductive yarn ( 2 ) is electrically insulated from the electrically resistive yarn ( 3 ), wherein said electrically resistive yarn ( 3 ) is a plastic yarn filled with electrically conductive elements.

2. The composite yarn ( 1 ) according to claim 1 , wherein said electrically conductive yarn ( 2 ) and said electrically resistive yarn ( 3 ) are coupled by twisting.

3. The composite ( 1 ) yarn according to claim 1 , wherein said electrically conductive yarn ( 2 ) and said electrically resistive yarn ( 3 ) form a sensing core (la) of said composite yarn ( 1 ), said composite yarn ( 1 ) further comprising a sheath ( 1 b ) made of an electrically non-conductive material covering said sensing core (la).

4. The composite yarn ( 1 ) according to claim 3 , wherein said sheath (lb) of said electrically non-conductive material comprises staple fibers ( 4 ), said sensing core (la) being preferably core-spun with said staple fibers ( 4 ).

5. The composite yarn ( 1 ) according to claim 4 , wherein said staple fibers ( 4 ) are natural fibers.

6. The composite yarn ( 1 ) according to claim 1 , wherein said electrically conductive yarn ( 2 ) is an insulated metal wire.

7. The composite yarn ( 1 ) according to claim 1 , wherein the electrical resistance per unit of length Rc of said electrically conductive yarn ( 2 ) is at least two order of magnitude less than the electrical resistance per unit of length Rr of said electrically resistive yarn ( 3 ), preferably Rr/Rc is in range of 100 to 1000000.

8. A capacitive touch sensor ( 10 ) comprising at least one composite elongated element ( 1 ) comprising an electrically conductive elongated element ( 2 ) and an electrically resistive elongated element ( 3 ), wherein said electrically conductive elongated element ( 2 ) is coupled to said electrically resistive elongated element ( 3 ), and wherein the electrically conductive elongated element ( 2 ) is electrically insulated from the electrically resistive elongated element ( 3 ), said electrically conductive elongated element ( 2 ) and said electrically resistive elongated element ( 3 ) being configured to be electrically connected to a detection device ( 5 ) configured to evaluate the capacitance values (CR, CC) of the electrically resistive elongated element ( 3 ) and of the electrically conductive elongated element ( 2 ) of said composite elongated element ( 1 ), said detection device ( 5 ) being configured to calculate the ratio (CR/CC) between said capacitance values (CR, CC) of the electrically resistive elongated element ( 3 ) and of the electrically conductive elongated element ( 2 ) and to provide an output signal (SOUT) indicative of the location of a touch event along said composite elongated element ( 1 ) in function of said ratio (CR/CC).

9. The capacitive touch sensor ( 10 ) according to claim 8 comprising a plurality of said composite elongated elements ( 1 ), wherein said detection device ( 5 ) is configured to calculate the ratio (CR/CC) between said capacitance values (CR, CC) of the electrically resistive elongated element ( 3 ) and of the electrically conductive elongated element ( 2 ) for each composite elongated element ( 1 ) of said plurality of composite elongated elements ( 1 ) and to provide an output signal (SOUT) indicative of the location of a touch event along each composite elongated element ( 1 ) of said plurality of composite elongated elements ( 1 ).

10. The capacitive touch sensor ( 10 ) according to claim 9 wherein said composite elongated elements ( 1 ) are arranged substantially parallel to each other.

11. The capacitive touch sensor ( 10 ) according to claim 8 , wherein said one or more composite elongated elements ( 1 ) are coupled to a support layer.

12. The capacitive touch sensor ( 10 ) according to claim 11 , wherein said support layer is a fabric ( 9 ).

13. The capacitive touch sensor ( 10 ) according to claim 11 , wherein said support layer is a woven fabric ( 9 ) and wherein said one or more composite elongated elements ( 1 ) are at least part of the warp or of the weft of said woven fabric ( 9 ).

14. The capacitive touch sensor ( 10 ) according to claim 8 , wherein said at least one composite elongated element ( 1 ) is a composite yarn comprising an electrically conductive yarn ( 2 ) and an electrically resistive yarn ( 3 ), wherein said electrically conductive yarn ( 2 ) is coupled to said electrically resistive yarn ( 3 ), and wherein the electrically conductive yarn ( 2 ) is electrically insulated from the electrically resistive yarn ( 3 ).

15. The capacitive touch sensor ( 10 ) according to claim 8 , wherein said detection device ( 5 ) is connected to a communication module ( 8 ) configured to transmit said output signal (SOUT) to an external device ( 20 ).

16. A method for detecting a touch event and the location of said touch event on a support layer wherein said method comprises the following steps:
(a) providing a support layer comprising at least one composite elongated element ( 1 ) comprising an electrically conductive elongated element ( 2 ) and an electrically resistive elongated element ( 3 ), wherein said electrically conductive elongated element ( 2 ) is coupled to said electrically resistive elongated element ( 3 ), and wherein the electrically conductive elongated element ( 2 ) is electrically insulated from the electrically resistive elongated element ( 3 );
(b) evaluating the capacitance values (CR, CC) of the electrically resistive elongated element ( 3 ) and of the electrically conductive elongated element ( 2 ) of said at least one composite elongated element ( 1 );
(c) calculating the ratio (CR/CC) between the capacitance value (CR) of the electrically resistive elongated element ( 3 ) and the capacitance value (CC) of the electrically conductive elongated element ( 2 ) evaluated in said step (b);
(d) providing an output signal (SOUT) indicative of the location of said detected touch event in function of said ratio (CR/CC) calculated in said step (c).

17. The method according to claim 16 , wherein said support layer is a fabric ( 9 ), and wherein said at least one composite elongated element ( 1 ) is a composite yarn comprising an electrically conductive yarn ( 2 ) and an electrically resistive yarn ( 3 ), wherein said electrically conductive yarn ( 2 ) is coupled to said electrically resistive yarn ( 3 ), and wherein the electrically conductive yarn ( 2 ) is electrically insulated from the electrically resistive yarn ( 3 ).

Assignees

• Sanko Tekstil Isletmeleri San Ve Tic As

Inventors

• Cobanoglu Ozgur
• Caglar Fehim
• Kazanc Semih
• Iyidogan Deniz
• Agzikara Seref
• Erkus Ertug
• Evran Erkan
• Eren Nafiz
• Oguz Onur Birkan
• Selcuk Nurullah

Classifications

• G06F3/0448

  Details of the electrode shape, e.g. for enhancing the detection of touches, for generating specific electric field shapes, for enhancing display quality · CPC title

• G06F3/0446 Primary

  using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes · CPC title

• G06F3/04164

  Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads · CPC title

• G06F3/0416

  Control or interface arrangements specially adapted for digitisers · CPC title

• G06F3/044

  by capacitive means · CPC title