Electronic textile and method of manufacturing an electronic textile

Abstract

A method of manufacturing an electronic textile (1) comprising the steps of: providing a textile carrier (2) comprising a plurality of conductor lines (6a-b); releasably attaching (101) the textile carrier (2) to a rigid support plate (20); providing (102) a conductive substance on the textile carrier (2) in a pattern forming a plurality of sets of connection pads (5a-b) on the textile carrier (2), each set of connection pads defining a component placement position for placement of an electronic component (3), and each set of connection pads (5a-b) comprising a connection pad overlapping one of the conductor lines, the connection pad having a connection pad length (L.sub.cp) in a direction parallel to the conductor line and a connection pad width (W.sub.cp) in a direction perpendicular to the conductor line, wherein the connection pad width (W.sub.cp) is at least one percent of an extension (W.sub.tc) of the textile carrier (2) in the direction perpendicular to the conductor line; automatically placing (103) electronic components (3) at the component placement positions; curing (104) the conductive substance to attach the electronic components (3) to the textile carrier (2), thereby forming the electronic textile (1) and removing (105) the electronic textile from the rigid support plate.

Claims

1. An electronic textile comprising: a textile carrier having a plurality of conductor lines (6a-b); a plurality of sets of connection pads (5a-b), each pad of the set overlapping only one of said conductor lines (6a-b) and having a connection pad length (L.sub.cp) in a direction parallel to said conductor line and a connection pad width (W.sub.cp) in a direction perpendicular to said conductor line; and a plurality of electronic components each having at least a first component pad (8a) being electrically connected to one of said conductor lines (6a) via one of said connection pads (5a), wherein said textile carrier has a fixed length extension (W.sub.tc) in said direction perpendicular to the conductor line and wherein said connection pad width (W.sub.cp) is at least one percent of the extension (W.sub.tc).

2. The electronic textile according to claim 1, wherein said component pad has a component pad length (1) in a direction parallel to said conductor line and a component pad width (w) in a direction perpendicular to said conductor line, and said connection pad width (W.sub.cp) is at least equal to said component pad width of the component pad that is connected to said connection pad.

3. The electronic textile according to claim 1, wherein said connection pad length (L.sub.cp) is at least equal to said component pad length (1).

4. The electronic textile according to claim 1, wherein said textile carrier comprises a plurality of interwoven conductive yarns and non-conductive yarns, said plurality of conductor lines (6a-b) being formed by conductive yarns.

5. The electronic textile according to claim 1; wherein the textile carrier comprises a top surface and a bottom surface; and, wherein each of said overlappings occurs by positioning the connection pad on only one surface of the textile carrier's top and bottom surfaces.

6. The electronic textile according to claim 1; wherein each of said overlappings occurs without cutting the conductor line.

7. The electronic textile according to claim 6, wherein said plurality of electronic components comprises at least one light-emitting diode.

8. An electronic textile comprising: a textile carrier having a plurality of conductor lines (6a-b): a plurality of sets of connection pads (5a-b), each pad of the set overlapping only one of said conductor lines (6a-b) and having a connection pad length (L.sub.cp) in a direction parallel to said conductor line and a connection pad width (W.sub.cp) in a direction perpendicular to said conductor line; and a plurality of electronic components each having at least a first component pad (8a) being electrically connected to one of said conductor lines (6a) via one of said connection pads (5a), wherein said connection pad width (W.sub.cp) is at least one percent of an extension (W.sub.tc) of said textile carrier in said direction perpendicular to the conductor line, wherein said connection pads (5a-b) are formed by conductive glue.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) 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:

(2) FIG. 1a schematically illustrates an electronic textile according to an exemplary embodiment of the present invention;

(3) FIG. 1b is a schematic cross-section view of the electronic textile in FIG. 1a;

(4) FIG. 2 is a flow-chart schematically illustrating an embodiment of the method according to the present invention.

(5) FIG. 3 is a schematic illustration of certain steps of a method according to a first exemplary embodiment of the method according to the present invention; and

(6) FIG. 4 is a schematic illustration of certain steps of a method according to a second exemplary embodiment of the method according to the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(7) FIG. 1a schematically illustrates an exemplary electronic textile 1 comprising a textile carrier 2 and a plurality of electronic components, here in the form of light-emitting diodes (LEDs) 3 (only one of these is indicated in the drawing to avoid cluttering the drawing). In the exemplary embodiment shown in FIGS. 1a-b, the textile carrier 2 is provided in the form of a woven fabric comprising interwoven conductive yarns and non-conductive yarns.

(8) On the textile carrier 2, a plurality of sets of connection pads 5a-b are provided such that a first connection pad 5a overlaps a first conductor line 6a, and the second connection pad 5b overlaps a second conductor line 6b, which is substantially parallel with the first conductor line 6a (again, only one set of connection pads and associated conductor lines are indicated in the drawing to avoid cluttering the drawing). Each LED 3 is electrically connected to a pair of conductor lines 6a-b. The conductor lines may be interrupted at one or more positions. Often, between two consecutive LEDs one of the conductor lines is interrupted, alternately the first and the second conductor line. This allows the LEDs to be connected in series via an associated set of connection pads 5a-b, as is schematically shown in the enlarged portion of the electronic textile 1 shown in FIG. 1a.

(9) As is indicated in the enlarged portion of FIG. 1a, each electronic component 3 comprises a first component pad 8a that is connected to the first conductor line 6a via the first connection pad 5a, and a second component pad 8b that is connected to the second conductor line 6b via the second connection pad 5b.

(10) Each connection pad 5a-b has a connection pad width W.sub.cp, and a connection pad length L.sub.cp, and each component pad 8a-b has a component pad width w and a component pad length 1. Furthermore, as is indicated in FIG. 1a, the textile carrier 2 has an extension W.sub.tc in the direction perpendicular to the conductor lines 6a and 6b. To provide for automatic manufacturing with high yield of the electronic textile 1, the width W.sub.cp of the connection pads 5a-b is at least one percent of the extension W.sub.tc of the textile carrier 2 in the direction perpendicular to the conductor lines 6a and 6b. Preferably, the width W.sub.cp of the connection pads 5a-b is at least two percent of the extension W.sub.tc of the textile carrier 2 in the direction perpendicular to the conductor lines 6a and 6b. This typically means that the connection pads 5a-b are considerably larger than their associated component pads 8a-b. In the example that is illustrated by FIGS. 1a-b, the connection pad length L.sub.cp is greater than the component pad length 1, and as can best be seen in FIG. 1b, which is a cross-section view of the enlarged portion of the electronic textile 1 in FIG. 1a, the connection pad width W.sub.cp is more than two times the component pad width w.

(11) Through this particular dimensioning, the inventors have found that the electronic textile 1 can be manufactured using automatic component placement equipment otherwise used for placing components on rigid printed circuit boards with a sufficiently high production yield. This is possible, since the dimensional tolerances due to inaccuracies of the textile carrier 2 are compensated for by the oversized connection pads 5a-b.

(12) An exemplary method of manufacturing the electronic textile 1 described above in connection with FIGS. 1a-b will now be described with reference to FIG. 2.

(13) In the first step 101, the textile carrier 2 is releasably attached to a rigid support plate. Two exemplary ways of carrying out this step will be described further below with reference to FIGS. 3 and 4.

(14) Following the attachment of the textile carrier to the rigid support plate, a conductive substance is applied to form the connection pads in step 102. The conductive substance may, for example, be a solder paste or a conductive glue, and may be applied in any suitable manner, such as screen printed or dispensed.

(15) Subsequently, in step 103, the electronic components are automatically placed at component placement positions defined by the connection pads provided in step 102.

(16) Thereafter, in step 104, the conductive substance is cured, which may, for example, be done by placing the textile carrier, with the electronic components loosely attached thereto by the conductive substance, and still attached to the rigid support plate, in an oven.

(17) Finally, in step 105, the finished electronic textile is removed from the rigid support plate.

(18) Two exemplary ways of carrying out the above-mentioned step 101 of releasably attaching the textile carrier 2 to a rigid support plate 20 will now be described with reference to FIGS. 3 and 4.

(19) According to the first exemplary way, as is schematically shown in FIG. 3, the rigid support plate 20 is provided with easy-to-detach adhesive in an area 21 substantially corresponding to the extension of the textile carrier 2. The rigid support plate 20 is further provided with reference markers (sometimes also referred to as fiducials) 22a-d for allowing alignment of the automatic placement equipment, and guides 23a-d for assisting in the alignment of the textile carrier 2 relative to the fiducials 22a-d.

(20) As is schematically shown in FIG. 3, the textile carrier is aligned with the guides 23a-d and pressed flat against the area 21 with the adhesive. As indicated in FIG. 3, the textile carrier 2 may be rolled out, but of course other ways of attaching the textile carrier to the rigid support plate 20 are possible.

(21) After the textile carrier has been aligned with the guides 23a-d and pressed flat against the rigid support plate 20 to remove any wrinkles (a procedure which may typically involve more or less tensioning of the fabric of the textile carrier 2), the textile carrier-support plate assembly is ready for the step 102 of applying the conductive substance.

(22) According to the second exemplary way, as is schematically shown in FIG. 4, there is provided a rigid alignment arrangement 25 comprising an alignment plate 26 and four mutually spaced apart alignment pins 27a-d that extend substantially perpendicularly from the rigid alignment plate 26.

(23) The textile carrier 2 comprises, as can be understood from FIG. 4, four spaced apart textile carrier apertures 28a-d that are arranged with mutual spacings corresponding to the alignment pins 27a-d, and the rigid support plate 20 with an easy-to-detach adhesive provided thereon (on the side thereof facing the textile carrier 2) is provided with four spaced apart support plate apertures 31a-d that are also arranged with mutual spacings corresponding to the alignment pins 27a-d. The textile carrier apertures may be formed by penetration of the alignment pins though the textile. The textile carrier may have markers at the positions where the alignment pins should penetrate.

(24) As is schematically illustrated in FIG. 4, the above-mentioned step of releasably attaching the textile carrier 2 to the rigid support plate is carried out by tensioning the textile carrier 2 and inserting the alignment pins 27a-d into the textile carrier apertures 28a-d, and then also inserting the alignment pins 27a-d into the support plate apertures 31a-d. Thereafter, the support plate 20 is pressed against the alignment plate 26 so that the textile carrier 2 is sandwiched therebetween and thus releasably attached to the adhesive provided on the rigid support plate 20.

(25) Thereafter, the textile carrier-support plate assembly is ready for the step 102 of applying the conductive substance.

(26) Additionally, variations to the disclosed embodiments can be understood and effected by the skilled person in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. For example, the textile carrier may comprise conductor lines extending in more than one direction, such as horizontal and vertical conductor lines. Electronic components may be connected between, for instance, one horizontal and one vertical conductor line. Moreover, the connection and component pads need not be rectangular, but can be of any shape.

(27) In the claims, the word comprising does not exclude other elements or steps, and the indefinite article a or an does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.