WO2010026511A1

WO2010026511A1 - Electronic textile with power distributing structure

Info

Publication number: WO2010026511A1
Application number: PCT/IB2009/053744
Authority: WO
Inventors: Rabin Bhattacharya; Liesbeth Van Pieterson
Original assignee: Koninklijke Philips Electronics N.V.
Priority date: 2008-09-04
Filing date: 2009-08-27
Publication date: 2010-03-11

Abstract

An electronic textile (300;400) comprising a textile substrate (102) having at least a first set of textile substrate conductors (202a-f,203a-e;403) each being arranged to enable electrical connection of an electronic device (209;401) thereto. The electronic textile further includes a first power distributing structure (301;405) arranged in electrical contact with each of the textile substrate conductors in the first set (202a-f,203a-e;403), and connectable to an external power source (210). The power distributing structure (301;405) has a substantially lower resistivity than each of the textile substrate conductors (202a-f,203a-e;403) to allow for an even distribution among the textile substrate conductors of power from the external power source (210).

Description

Electronic textile with power distributing structure

FIELD OF THE INVENTION

The present invention relates to an electronic textile and to a method for manufacturing such an electronic textile.

BACKGROUND OF THE INVENTION

Currently, research in the field of electronic textiles is very active, and although not a great deal of advanced electronic textile products can be found in the marketplace today, it is expected that many new products will find their way to the consumers in the near future. Many types of electronic textiles require that power is routed to a plurality of electronic components comprised in the electronic textile from a single power source, and/or routed from the electronic components to a single power sink, such as electrical ground.

Typically, however, electrical conductors comprised in an electronic textile have a relatively high resistance and a relatively low current carrying capability. When connecting a plurality of electronic components to a single power source and/or ground through such an electrical conductor, for example a conductive yarn, several drawbacks may thus occur, including, for example, power loss, voltage drop, excessive generation of heat, uneven distribution of power among the electronic components etc.

SUMMARY OF THE INVENTION

In view of the above-mentioned and other drawbacks of the prior art, a general object of the present invention is to provide an improved electronic textile and in particular an electronic textile enabling an improved distribution of power to and/or from electronic components comprised therein.

According to a first aspect of the present invention, these and other objects are achieved through a method of manufacturing an electronic textile, comprising the steps of: providing a textile substrate having at least a first set of textile substrate conductors each being arranged to enable electrical connection of an electronic device thereto; and providing a first power distributing structure to said textile substrate in such a way that said power distributing structure is in electrical contact with each of said textile substrate conductors comprised in the first set, and is connectable to an external power source.

By "textile" should, in the context of the present application, be understood a material or product manufactured by textile fibers. The textile may, for example, be manufactured by means of weaving, braiding, knitting, crocheting, quilting, or felting. In particular, a textile may be woven or non- woven.

It should be noted that the external power source may be a source of constant power or a source of modulated power in the form of signals, such as pulses. The present invention is based on the realization that an improved distribution of power in an electronic textile can be achieved by providing a power distributing structure in such a way that it is in electrical contact with each of a set of textile substrate conductors comprised in the textile substrate.

Hereby, it can be prevented that all the electrical current to/from several electronic components comprised in the electronic textile pass through a single section of one of the textile substrate conductors in the textile substrate. Instead, several current paths to/from electronic components comprised in the electronic textile can be achieved through the power distributing structure provided to the textile substrate.

By the provision of several current paths, the distribution of power to the electronic components can be improved, and the loss of power due to the, typically, low resistivity of the textile substrate conductors, such as conductive yarns, can be reduced. Furthermore, the reliability of the electronic textile can be improved, since the maximum current in the textile substrate conductors can be reduced.

To ensure that the power is more evenly distributed and that the loss of power is reduced, the power distributing structure may have a substantially lower resistivity than each of the textile substrate conductors comprised in the textile substrate.

For example, the resistivity (resistance per unit length) of the power distributing structure may advantageously be at least ten times lower than that of each of the textile substrate conductors. Additionally, the method according to the present invention allows for an optimized process for producing the electronic textile, since the textile substrate can be manufactured using a large scale process, such as weaving, for forming the textile substrate conductors, and the provision of the power distributing structure can take place after having cut the textile substrate to the desired size and shape. Accordingly, the textile substrate may advantageously be formed to the desired size and shape of the electronic textile prior to the provision of the power distributing structure.

It should be noted that the power distributing structure may be provided before or after mounting components on the textile substrate. The power distributing structure may, furthermore, advantageously be provided along at least a portion of the perimeter of the textile substrate. Hereby, the above- discussed improved power distribution and reduced loss of power can be achieved in combination with an unobtrusive placement of the power distribution structure.

According to one embodiment, the power distributing structure may be attached to the textile substrate. In this embodiment, the power distributing structure may be a flexible element, such as a band, a foil, a wire, a conductive multi- filament yarn or a ribbon woven from conductive yarns. The flexible element may be attached to the textile substrate by any suitable fastening method, including, for example, gluing, stitching, embroidering, riveting, quilting, ultrasonic welding, crocheting, lamination, soldering etc. Alternatively, the power distributing structure may be formed by a conductive substance that may be applied to the textile substrate. Such a conductive substance may, for example, be a conductive glue or a conductive ink. The conductive substance may, for instance, be applied to the textile substrate using dispensing techniques or printing (including screen printing and inkjet printing). Moreover, the textile substrate may further comprise a second set of textile substrate conductors each being arranged to enable electrical connection of an electronic device thereto, and the method according to the present invention may further comprise the step of providing a second power distributing structure to the textile substrate in such a way that the second power distributing structure is in electrical contact with each of the textile substrate conductors comprised in the second set.

According to a second aspect of the present invention, the above-mentioned and other objects are achieved through an electronic textile comprising: a textile substrate having at least a first set of textile substrate conductors each being arranged to enable electrical connection of an electronic device thereto; and a first power distributing structure arranged in electrical contact with each of the textile substrate conductors in the first set, and connectable to an external power source, the power distributing structure having a substantially lower resistivity than each of the textile substrate conductors in the first set to allow for an even distribution among the textile substrate conductors of power from the external power source. Further embodiments and effects associated with this second aspect of the invention are largely analogous to those provided above for the first aspect of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects of the present invention will now be described in more detail, with reference to the appended drawings showing currently preferred embodiments of the invention, wherein:

Fig. 1 schematically illustrates an exemplary cut-to-measure electronic textile; Fig. 2 is a schematic diagram illustrating an exemplary prior art connection of an external power supply to electronic devices comprised in a part of the electronic textile in Fig. 1;

Fig. 3a is a schematic illustration of an electronic textile according to a first embodiment of the present invention; Fig. 3b is a schematic diagram illustrating the wiring of the electronic textile in Fig. 3a;

Fig. 4 is a schematic illustration of an electronic textile according to a second embodiment of the present invention; and

Fig. 5 is a flow-chart schematically illustrating a manufacturing method according to an embodiment of the invention.

DESCRIPTION OF A PREFERRED EMBODIMENT OF THE PRESENT INVENTION

In the following description, the present invention is described with reference to an electronic textile in the form of a simplified cut-to-measure textile display device having a very limited number of pixels.

It should be noted that this by no means limits the scope of the invention, which is equally applicable to other electronic textiles requiring power distribution among electronic components comprised therein. Examples of such electronic textiles include various distributed systems, such as distributed sensor networks, actuator systems etc. Fig. 1 schematically illustrates a cut-to-measure textile substrate having a plurality of light-emitting devices connected thereto, and schematically illustrates cutting of the textile substrate to a desired size and shape. In Fig. 1, the textile substrate 100 is shown as a sheet having a plurality of pixels 101 (only one of these is indicated for the sake of clarity of drawing). This sheet may, for example, be a woven fabric in which the pixels 101 are addressable through conductive yarns interwoven in the fabric.

In Fig. 1, furthermore, an exemplary cut is indicated by the dashed line, separating a cut-out textile substrate 102 having the desired size and shape as an electronic textile from the remainder of the sheet 100.

To provide the desired cut-to-measure functionality, the cut-out textile substrate 102 may, for example, have the robust wiring schematically illustrated in Fig. 2. Such a wiring may be realized in various ways, such as by weaving, which is described in more detail in WO 2008/044167. The cut-out textile substrate 102 includes an upper layer conductive grid 201 which is indicated by the solid grid lines in rows 202a-f and columns 203 a-e, and a lower layer conductive grid 204 which is indicated by the dotted grid lines in rows 205a-f and columns 206a-e.

From the lower layer conductive grid 202, vias are formed through the fabric, resulting in the indicated connection points 207 in each upper grid element (connection point is indicated by a reference numeral to avoid cluttering the figure). Between each of these connection points and corresponding connection points 208 of the upper conductive grid, a LED 209 is connected (once again, only one each of these is indicated by a reference numeral).

In order to power the LEDs, a power supply, here simply indicated as a single voltage source 210 may be connected between the upper and lower conductive grids 201, 204 in the manner indicated in Fig. 2.

When powering the electronic components, here LEDs 209, comprised in the electronic textile 102 using the prior art wiring shown in Fig. 2, the current Ii passing through the section of the first column conductor 203a closest to the power supply 210 needs to be sufficient to power all the LEDs 209 and to compensate for the power loss occurring due to the relatively high resistivity of the textile substrate conductors 202a-f and 203a-e. Depending on application, the reliability of the electronic textile may be adversely affected by the high maximum current Ii required using the wiring of Fig. 2,

Fig 3 a schematically shows an electronic textile 300 according to an embodiment of the present invention, in which the cut-out textile substrate 102 in Fig. 1 has been provided with first 301 and second 302 power distributing structures in the form of conductive bands stitched along the edges of the textile substrate 102. For illustration purposes, the conductive bands 301, 302 are shown as being connected to a power supply 210 in the form of a battery to power the LEDs 209 comprised in the electronic textile 300. Turning now to Fig. 3b, which is a circuit schematic of the electronic textile in Fig. 3a, it can be seen that the power supplied by the power supply 210 is now distributed among the textile substrate conductors 202a- f, 203 a-e in such a way that the (maximum) current passing through any one of the textile substrate conductors is reduced to the required total current divided by the number of connections between textile substrate conductors and the power distributing structure 301. Accordingly, in the presently illustrated example, the maximum current passing through any section of the textile substrate conductors is reduced by at least a factor 20 (the number of connections between the rows and columns in the upper(lower) layer conductive grid and the first (second) power distributing structure) given that all other factors, such as number of currently powered electronic devices, are equal. Fig. 4 is a schematic illustration of an electronic textile 400 according to a second embodiment of the present invention. Similarly to the electronic textile 300 described above in connection with Figs. 3a-b, the electronic textile 400 in Fig. 4 includes a textile substrate 102, in this case a woven textile with interwoven conductive and non-conductive yarns, and a plurality of LEDs. In the electronic textile 400 in Fig. 4, the LEDs are provided in two sets 401 and 402, which are controllable independently of each other. One terminal of each LED in the first set 401 is connected to a textile substrate conductor, here in the form of a conductive yarn, in a first set 403 of conductive yarns and one terminal of each LED in the second set 402 is connected to a textile substrate conductor, here in the form of a conductive yarn, in a second set 404 of conductive yarns. The other terminal of each LED comprised in the electronic textile 400 is connected to a textile substrate conductor comprised in a third set (not shown in Fig. 4) of conductive yarns.

As can be seen in Fig. 4, the electronic textile 400 has a first power distributing structure 405 which is electrically connected to each conductive yarn in the first set 403 of conductive yarns, a second power distributing structure 406 which is electrically connected to each conductive yarn in the second set 404 of conductive yarns, and a third power distributing structure 407 which is electrically connected to each conductive yarn in the third set of conductive yarns.

As is illustrated in the enlarged portion of Fig. 4, the power distributing structures are, in the present embodiment, provided in the form of a substance that has been applied to the textile substrate 102. By applying a conductive substance by, for example, screen printing or inkjet printing, power distributing structures can be formed with high precision to provide power distribution among a selected set of textile substrate conductors. An embodiment of a method for manufacturing an electronic textile according to embodiments of the present invention will now be described with reference to the flow chart in Fig. 5.

In a first step 501, a textile substrate 102 having at least a first set 403 of textile substrate conductors is provided. The textile substrate 102 may or may not have electronic components connected thereto.

In a second step 502, a first power distributing structure 405 is then provided in electrically conductive connection with each of the textile substrate conductors in the first set 403. The person skilled in the art will realize that the present invention is by no means limited to the preferred embodiments. For example, the power distributing structures need not be provided along the edges of the electronic textile, but may, depending on application, equally well be otherwise located in the electronic textile, such as along the center thereof.

Claims

CLAIMS:

1. A method of manufacturing an electronic textile (300; 400), comprising the steps of: providing (501) a textile substrate (102) having at least a first set of textile substrate conductors (202a-f, 203a-e; 403) each being arranged to enable electrical connection of an electronic device (209; 401) thereto; and providing (502) a first power distributing structure (301; 405) to said textile substrate (102) in such a way that said power distributing structure is in electrical contact with each of said textile substrate conductors comprised in the first set, and is connectable to an external power source (210).

2. The method according to claim 1, wherein said at least first power distributing structure (301; 405) is provided along at least a portion of a perimeter of said textile substrate (102).

3. The method according to claim 1 or 2, wherein said step of providing said at least first power distributing structure (301) comprises the step of: attaching said power distributing structure (301) to said textile substrate (102).

4. The method according to claim 3, wherein said power distributing structure (301) is attached to said textile substrate (102) using any one of gluing, stitching, embroidering, riveting, quilting, ultrasonic welding, crocheting, lamination and soldering.

5. The method according to claim 1 or 2, wherein said step of providing said at least first power distributing structure (405) comprises the step of: applying a conductive substance to said textile substrate (102).

6. The method according to any one of the preceding claims, wherein said textile substrate (102) further comprises a second set of textile substrate conductors (205a- f, 206a-e; 404) each being arranged to enable electrical connection of an electronic device (209; 402) thereto, further comprising the step of: providing a second power distributing structure (302; 406) to said textile substrate (102) in such a way that said power distributing structure is in electrical contact with each of said textile substrate conductors comprised in the second set.

7. An electronic textile (300; 400) comprising: a textile substrate (102) having at least a first set of textile substrate conductors (202a- f, 203a-e; 403) each being arranged to enable electrical connection of an electronic device (209; 401 ) thereto; and a first power distributing structure (301; 405) arranged in electrical contact with each of said textile substrate conductors in said first set (202a-f, 203a-e; 403), and connectable to an external power source (210), said power distributing structure (301; 405) having a substantially lower resistivity than each of said textile substrate conductors (202a- f, 203a-e; 403) to allow for an even distribution among said textile substrate conductors of power from said external power source (210).

8. The electronic textile (300; 400) according to claim 7, said power distributing structure (301; 405) being arranged along at least a portion of a perimeter of said textile substrate (102).

9. The electronic textile (300) according to claim 7 or 8, wherein said power distributing structure (301) comprises a flexible conductive element being attached to said textile substrate ( 102) .

10. The electronic textile (300) according to claim 9, said conductive element (301; 405) being attached to said textile substrate (102) through any one of gluing, stitching, embroidering, riveting, quilting, ultrasonic welding, crocheting, lamination and soldering.

11. The electronic textile (400) according to claim 7 or 8, said conductive element being a conductive substance (405) adhered to said textile substrate (102).

12. The electronic textile (300; 400) according to any one of claims 7 to 11, further comprising a second set of textile substrate conductors (205 a- f, 206a-e; 404) each being arranged to enable electrical connection of an electronic device (209; 402) thereto; and a second power distributing structure (302; 406) arranged in electrical contact with each of said textile substrate conductors in said second set (205a-f, 206a-e; 404), and connectable to an external power source, said power distributing structure (302; 406) having a substantially lower resistivity than each of said textile substrate conductors (205 a- f, 206a-e; 404) to allow for an even distribution among said electrical conductors of power from said external power source.