GB2472026A

GB2472026A - Signalling device

Info

Publication number: GB2472026A
Application number: GB0912674A
Authority: GB
Inventors: Tilak Dias; Anura Fernando
Original assignee: ENTELLFIBRES Ltd; University of Manchester
Current assignee: ENTELLFIBRES Ltd; Muhammad Hafiz
Priority date: 2009-07-21
Filing date: 2009-07-21
Publication date: 2011-01-26
Also published as: WO2011010093A1; GB0912674D0

Abstract

A signalling device comprises a semi-conductor chip 6 confined with the filaments 4 of a multi-filament yarn and conductive elements 8 extending from the chip in both directions along the yarn to form antena. The chip is in an enclosed capsule comprising filaments of the yarn and the filaments may have resin cured between them and the antena may be bound in the resin. The antena elements may be entrained in the yarn filaments and the yarn may extend beyond the antena in both directions. The chip may comprise multiple components one of which may be a light-emitting diode, a sound emitting device or a signal transmitter. The yarn may include conductive filaments connected to the chip. The yarn may be bent to form the shape of the antena. The chip may be mounted onto a conductive backing also confined within the multi-filaments. A series of filaments may be fed radially by drawing along a central axis, the chip and backing being delivered to the filaments at the axis at which point a resin is added and the composite moulded in a split tubular mould while the yarn is held stationary.

Description

I

Signalling Devices This invention relates to signalling devices. Such devices may be in the form of a tag or label, or be adapted for incorporation in or attachment to a substrate.

International Patent Publication No: WO 2006/123 133 discloses the concept of installing an operative device such as a computer chip within the structure of a yarn. It also discloses a method of installing such a device in the yarn in a continuous process in which devices are delivered seriatim between filaments as they are drawn to form the multifilament yam.

British Specification No: 2,323,254 refers to a transponder device comprising a plurality of filaments stranded together to form a yarn and including the transponder. A signalling device of the present invention comprises a semi-conductor chip with conductive elements forming antenna extending therefrom, confined within a monofilament or multifilament yarn with the antenna extending in both directions along the yarn. The antenna elements may be entrained within the yarn filaments. The chip is in an enclosed capsule comprising filaments of the yarn, and such a capsule may comprise the filaments and a resin cured therebetween, The conductive elements can be elecrto-conductive fibres or filaments, possibly mounted on a backing. The chip is typically an RFID chip.

The length of the yarn on either side of the capsule does not have to match the length of the antenna. It can extend beyond the antenna in one or both directions. The extended length of yarn can thus be used to attach the device to an item or product.

Such extended lengths of yarn can also be used to bend the antenna into predetermined shapes to enhance their ability to receive and emit signals. Of course, shaped antenna can also be created when the length of the yarn is coextensive with the antenna. To accomplish this the yarn itself can be capable of plastic deformation, or made so by impregnation with a suitable resin which will also serve to locate and fix the chip within the yarn.

The chip in a device according to the invention can itself be part of a unit comprising a plurality of components such as those that emit an audible or visible signal. For example, such a component could be a light emitting diode coupled to a battery. Alternatively, if one of the components in a multi-component unit requires a power supply, the multifilament yarn can include conductive filaments to connect it to an external power source.

The invention is also directed at a method of making a signalling device of the kind described above. In the method, the semi-conductor chip is mounted on a conductive backing such as an electro-conductive filament fibre, which extends from opposite sides of the chip. The chip and backing are then confined within a monofilament yarn, or the filaments of a multi-filament yarn, with the backing extending from the chip in both directions along the yam to form antenna. The resultant product can be used as a radio frequency identification device, in yarn form.

The invention will now be described by way of example and with reference to the accompanying schematic drawings wherein: FIGURE 1 shows a cross-section through a signalling device according to the invention; FIGURE 2 shows a view similar to Figure 1, but with conductors attached to the semi-conductor chip; FIGURE 3 shows a conductive backing upon which a semi-conductor chip is mounted; FIGURE 4 illustrates apparatus in which the signalling device can be installed within the structure of a multifilament yarn.; and FIGURE 5is an enlarged view of a section of the apparatus of Figure 4 where the signalling device is installed.

Figure 1 shows a yam 2 with multiple filaments 4 extending alongside and around a semi-conductor chip 6 with antenna 8 extending in either direction along and within the yarn. As can be seen, the yam filaments form a slight bulge around the chip 6.

However, the dimensions of the chip are typically around one millimetre, and can be readily incorporated in multifilament yams without creating a substantial distortion.

The yarn with the installed transponder can then be used for multiple purposes including knitting, braiding and weaving into fabrics. It can also be embroidered onto existing fabrics, and if the yarn has appropriate plasticity, it can be bent to create a selected shape of antenna.

Figure 2 shows a yarn section similar to Figure 1, but with additional conductors extending within the yarn from the transponder for connection to an external power source. It will be noted that in each of the embodiments illustrated in Figures 1 and 2, the yarn extends beyond the antenna. This enables semi-conductor chips and antennas to be installed in successive lengths of the same yarn, in a continuous production process of the kind that is described below.

Figure 3 illustrates a preferred technique for creating the transponder-antenna combination. The antenna 8 are first formed on a backing 12 by spattering or electro-deposition. The chip 6 is then secured on the backing, with appropriate contact with the respective antenna. The backing is then trimmed away, along lines 14, such that its lateral dimension is substantially equal to that of the chip, and it is then ready for installation in the yarn 2. It will be noted that the backing, which does not need to be conductive, can extend beyond the antenna to provide tags useful for handling the combination for installation in the yarn.

Figure 4 illustrates a technique for installing the semi-conductor chip and antenna in a multifilament yarn. It is essentially a pultrusion technique in which individual filaments 4 are drawing from multiple radial directions to a central axis 14 along which they are drawn downwardly as shown. Above the point at which the filaments converge is a feeder 16 for delivering the chip and antenna along line 18 to the yarn axis 14. The combination is suspended and progressively lowered to the point of convergence of the filaments 4 whereafter it is then drawn in to the converging filaments, which then combine to hold the chip and antenna in place. The apparatus is similar to that disclosed in International Patent Specification No. W02006/l23,133, the disclosure whereof is incorporated by reference. In this embodiment it will be appreciated that the process is facilitated by forming multiple chip-antenna combinations on successive lengths of backing to facilitate their suspension over the converging filaments. The final trimming can be conducted at the feeder station 16 just prior to delivery of the combination. A combination can be separated from its successor just prior to it reaching the converging filaments, and the delivery of chip-antenna combinations halted to create the desired additional length of yarn between adjacent antenna ends. This can of course be accomplished with an appropriate stepping motor.

The technique illustrated in Figure 4 is also readily adaptable to provide for the addition at 24 of a quantity of resin from reservoir 26 to the chip-antenna combination which will also be absorbed by the multiple filaments in the yarn. As shown in Figure 5, a curing station 20 can be created at an appropriate distance past the point 22 of filament convergence so that the resultant yam drawn along the axis 14 has the chip and antenna safely secured therein by means of the cured resin. The curing station 20 may take the form of a mould tube through which the yam is drawn, but it is preferred to use a split mould having a plurality of parts movable laterally with respect to the yarn axis.

This reduces the risk of the yarn adhering to the mould wall. The mould parts are adapted to close around the yarn while the yarn is held stationary, and the mould cavity is exposed to ultra-violet radiation to cure the resin. The geometry of the apparatus is designed to enable the yarn and transponder in the mould cavity to be held stationary by the device (not shown) drawing the yarn, simultaneously with the registration of the transponder/backing combination with the yam filaments by micro-processor controlled motors, and its trimming and separation from a subsequent combination in a strip supply.

Claims

CLAIMS: 1. A signalling device comprising a semi-conductor chip confined within the filaments of a length of multifilament yam and conductive elements extending from the semi-conductor chip in both directions along the yarn to form antenna, wherein the chip is in an enclosed capsule comprising filaments of the yarn.
2. A device according to Claim 1 wherein the antenna elements are entrained within the yarn filaments.
3. A device according to Claim 1 or Claim 2 wherein the chip is mounted on an electroconductive fibre filament backing forming the antenna.
4. A device according to any preceding Claim wherein the capsule comprises the filaments and a resin cured therebetween.
5. A device according to any preceding Claim wherein the yarn extends beyond the antenna in both said directions.
6. A device according to any preceding Claim wherein the antenna are bound in resin.
7. A device according to any preceding Claim wherein the semi-conductor chip is part of a unit comprising a plurality of components.
8. A device according to Claim 7 wherein one of the components is a light-emitting diode, a sound emitting device or a signal transmitter.
9. A device according to any preceding Claim wherein the multifilament yarn includes conductive filaments connected to the chip.
10. A device according to any of Claims 1 to 8 wherein the yarn extending from the chip is bent to form the antenna into predetermined shapes.
11. A device according to Claim 10 mounted on a substrate.
12. A method of making an signalling device comprising the steps of: mounting a semi-conductor chip on a conductive backing to form antenna extending in opposite directions from the chip; and confining the chip and backing within the filaments of a multifilament yarn with the backing extending from the chip in both directions along the yarn to form antenna.
13. A method according to Claim 12 wherein the backing comprises conductive fibre filaments.
14. A method according to Claim 12 or 13 wherein filaments of the yarn form a capsule enclosing the chip.
15. A method according to Claim 14 wherein the capsule comprises the filaments and a resin cured therebetween.
16. A method according to any of Claims 12 to 15 wherein the multifilament yarn is formed by delivering a plurality of filaments centripetally to a central axis and drawing them along the axis, and wherein the chip and backing is delivered to the conjoining filaments at the axis.
17. A method according to Claim 16 wherein the resin is delivered to the filaments and the formed yam and resin with the chip and backing are drawn through a mould in which the resin cures.
18. A method according to Claim 17 wherein the yarn is held stationary relative to the mould while the resin cures.
19. A method according to Claim 17 or Claim 18 wherein the mould is a tube through which the yam is drawn.
20. A method according to Claim 17 or Claim 18 wherein the mould comprises a plurality of parts movable laterally relative to the yam axis.
21. A method according to any of Claims 17 to 20 wherein the resin is delivered to the conjoining filaments at the central axis.