US20200325603A1

US20200325603A1 - Knitted textiles with conductive traces of a hybrid yarn and methods of knitting the same

Info

Publication number: US20200325603A1
Application number: US16/845,772
Authority: US
Inventors: Clare King; Anjali Khemani; Birgit Leitner
Original assignee: Propel LLC
Current assignee: Propel LLC
Priority date: 2019-04-10
Filing date: 2020-04-10
Publication date: 2020-10-15
Also published as: US20210277544A1; EP3952734A4; US11891729B2; WO2020210644A1; EP3953508A1; EP3952734A1; WO2020210646A1; US11905627B2; EP3958739A1; WO2020210648A1; US20200323491A1; EP3953508A4; EP3958739A4

Abstract

A textile made from a single knitted layer having an inert region and a conductive trace region is disclosed. The inert region is knitted using an electrically inert or non-externally conductive yarn and the conductive trace region is knitted from a hybrid yarn containing a non-conductive yarn twisted with a conductive wire, with the conductive wire having an exterior insulating layer. The conductive trace can transmit an electrical data or power signal along the textile via the conductive wire. The insulating layer of the wire can be removed in the conductive trace region to expose the conductive exterior of the wire to enable electrical connections to the conductive trace region. The textile can include a textile electrode knitted from an externally conductive yarn and the conductive trace region can be electrically connected to the electrode to transmit an electrical signal to or from the textile electrode.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from U.S. Provisional Application Ser. No. 62/832,098 filed Apr. 10, 2019 and entitled GARMENTS WITH INTEGRATED ELECTRODES AND CONDUCTIVE TRACES; from U.S. Provisional Application Ser. No. 62/832,101 filed Apr. 10, 2019 and entitled SYSTEMS AND METHODS FOR MAINTAINING MOISTURE IN A TEXTILE ELECTRODE; and from U.S. Provisional Application Ser. No. 62/832,104 filed Apr. 10, 2019 and entitled HYBRID YARN FOR WEAVING CONDUCTIVE WIRES INTO FABRIC. The contents of U.S. Provisional Application Ser. No. 62/832,098, U.S. Provisional Application Ser. No. 62/832,104, and U.S. Provisional Application Ser. No. 62/832,101 are hereby incorporated in their entireties by reference.
The subject matter of this patent application may be related to the subject matter of U.S. patent application Ser. No. ______ entitled SYSTEMS FOR MAINTAINING MOISTURE IN A TEXTILE ELECTRODE filed on even date herewith and U.S. patent application Ser. No. ______ entitled MACHINE-KNITTABLE CONDUCTIVE HYBRID YARNS. Each of these patent applications is hereby incorporated herein by reference in its entirety.

GOVERNMENT RIGHTS

This invention was made with Government support under Grant No. N00189-17-C-Z023 awarded by the U.S. Navy. The Government has certain rights in the invention.

FIELD

The disclosure relates to textiles with conductive traces and textile electrodes integrated into a single-layer of fabric.

BACKGROUND

Medical electrodes typically comprise a metallic surface in close contact with the skin, which is fixed on the skin by means of an adhesive, and the impedance between the skin and the metallic surface is reduced by the use of a conductive gel. More recently, garments have been designed that enable medical electrodes to be in contact with the skin while the garment is worn. The electrodes in the garments enable physiological properties of the wearer of the garment to be monitored over long periods of time (e.g., as long as the garment is worn). These physiological properties include measurement of an electrocardiographic signal, which is representative of the heart activity of a user who wears the garment. However, prior art garments with electrodes known to the inventors have been unable to seamlessly integrate an electrode into the fabric itself of the garment, and instead often require the electrode to be separately made and then applied to the garment, or multiple layers of fabric to support the electrode or have traditional wires running through the garment from the electrodes that interfere with the movement and comfort of the garment.

SUMMARY

Certain embodiments of the present disclosure provide a garment with integrated textile electrodes and conductive traces knitted into the garment to connect the textile electrodes to a control unit attached to the garment. Various embodiments include a textile, such as a wearable garment, knitted as a single continuous layer from different types of yarn, with a textile electrode formed as a region in the garment knitted with conductive yarn, the textile electrode being configured to receive an electrical signal from the body and transmit that signal along the conductive trace.
Embodiments of the present disclosure include a textile made from a single knitted layer having an inert region and a conductive trace region knitted together to form a continuous textile section of the single knitted layer, where the inert region is knitted using an electrically inert yarn and the conductive trace region is knitted from a hybrid yarn containing a non-conductive yarn twisted with a conductive wire, the conductive wire having an exterior layer of an insulating material. The conductive trace region can be configured to transmit an electrical data or power signal along the single knitted layer via the conductive wire from a first location in the continuous textile section to a second location in the continuous textile section. The conductive wire of the conductive trace region between the first and second locations can include one or more continuous lengths of the conductive wire spanning the first and second locations. The conductive trace region can be configured to transmit an electrical data or power signal along the single knitted layer via the conductive wire from a first region of the conductive trace region where the coating has been removed from the conductive wire to a second region of the conductive trace region where the coating has been removed from the conductive wire. The single-layer can define a first surface and a second surface opposite the first surface, and wherein a yarn of a given region of the single-layer is presented at both the first and second surfaces.
In some examples, the single knitted layer further includes an electrode region knitted using a conductive yarn, the conductive yarn comprising an exposed exterior surface of an electrically conductive material. A portion of a boundary of the electrode region can be knitted together with an adjacent portion of a boundary of the conductive trace region. In some embodiments, the exterior layer of the conductive wire of the conductive trace region adjacent to the electrode region is removed and the conductive wire contacts the conductive yarn such that the conductive trace region is electrically connected with the electrode region. In some embodiments, a second layer of the hybrid yarn is knitted of the conductive trace region of the continuous textile section and over a portion of the electrode region to form a two-layer section of the textile, and the exterior layer of the conductive wire of a portion of the conductive trace region in the two layer section is removed to expose a portion of the conductive wire and the exposed portion of the conductive wire is electrically connected with the electrode region via a conductive material. In some embodiments, the textile includes a section of the hybrid yarn of the conductive trace region extending out of the continuous textile section such that the section of the hybrid yarn can extend across a portion of the electrode region.
The hybrid yarn can include the non-conductive yarn twisted with two separate conductive wires each having an exterior separately coated with the insulating material. The conductive wire of the hybrid yarn can define a continuous length of conductive wire along each length of hybrid yarn of the conductive trace region. In some embodiments, the non-conductive yarn of the hybrid yarn includes at least one of an aramid, meta-aramid, or para-aramid polyamide fiber. The conductive wire of the hybrid yarn can include an exterior surface of a conductive metal and the insulating material comprises a polymer.
The single-layer can be knitted using a single-layer intarsia technique having all regions of the single-layer in the same intarsia layer. In some embodiments, the knitted textile is a garment and the inner surface of the single knit layer defines a skin-facing side of the garment and an outer surface of the single knit layer defines an exterior surface of the garment.
Yet another Embodiment of the present disclosure is a method of knitting a textile including knitting a single-layer of the textile from an electrically inert yarn and a hybrid yarn to form a continuous textile section by knitting the electrically inert yarn into an inert region of the single-layer and knitting the hybrid yarn into a conductive trace region of the single-layer, wherein the hybrid yarn includes a non-conductive yarn twisted with a conductive wire, the conductive wire having an exterior coated with an insulating material. The conductive trace region can be knitted to transmit an electrical data or power signal along the single knitted layer via the conductive wire from a first location in the continuous textile section to a second location in the continuous textile section. The conductive wire of the conductive trace region knitted between the first and second locations can include one or more continuous lengths of the conductive wire spanning the first and second locations.
In some embodiments, the method includes removing the coating of the conductive wire in a first region of the conductive trace region and removing the coating of the conductive wire in a section region of the conductive trace region, where the first and second regions are connected via a continuous section of the conductive trace region and the continuous section of the conductive trace region is configured to transmit an electrical data or power signal along the continuous textile section via the conductive wire from the first region to the second region. Removing the coating of the conductive wire in at least one of the first or second regions can include ablating the hybrid yarn to remove the non-conductive yarn and the coating on the conductive wire.
In some embodiments the method includes knitting the single-layer of the textile with a conductive yarn, the conductive yarn being knit into an electrode region of the continuous textile section, where the conductive yarn includes an exposed exterior surface of an electrically conductive material. A portion of a boundary of the electrode region can be knitted together with an adjacent portion of a boundary of the conductive trace region.
The method can further include removing the exterior layer of the conductive wire of the conductive trace region adjacent to the electrode region such that the conductive wire contacts the conductive yarn and the conductive trace region is electrically connected with the electrode region.
The method can further include knitting a second layer of the hybrid yarn out of the conductive trace region of the continuous textile section and over a portion of the electrode region to form a two-layer section of the textile, removing the exterior layer of the conductive wire of a portion of the conductive trace region in the two layer section to expose a portion of the conductive wire, and electrically connect the exposed portion of the conductive wire with the electrode region via a conductive adhesive. Removing the exterior layer of the conductive wire in the two layer section can include positioning a protective material between the first layer and the second layer and ablating the hybrid yarn in the second layer to remove the non-conductive yarn and the coating on the conductive wire, with the protective material preventing damage to the electrode region.
The method can further include extending a section of the hybrid yarn of the conductive trace region extending out of the continuous textile section such that the section of the hybrid yarn can extend across a portion of the electrode region.
In some embodiments, the single-layer defines a first surface and a second surface opposite the first surface, and wherein a yarn of a given region of the single-layer is presented at both the first and second surfaces.
In some embodiments, the hybrid yarn comprises the non-conductive yarn twisted with two separate conductive wires each having an exterior separately coated with the insulating material. The conductive wire of the hybrid yarn can define a continuous length of conductive wire along each length of hybrid yarn of the conductive trace region. The non-conductive yarn of the hybrid yarn can include at least one of an aramid, meta-aramid, or para-aramid polyamide fiber. The conductive wire of the hybrid yarn can include an exterior surface of a conductive metal and the insulating material comprises a polymer. The single-layer can be knitted using a single-layer intarsia technique having all regions of the single-layer in the same intarsia layer. In some embodiments, the single-layer is knitted using a single bed of a knitting machine. In some embodiments, each yarn of the single-layer is knit separately. In some embodiments, the textile is a garment and the inner surface of the single knit layer defines a skin-facing side of the garment and an outer surface of the single knit layer defines an exterior surface of the garment.
Other, features, and advantages of the subject matter included herein will be apparent from the description and drawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

This disclosure will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1A is a schematic illustration of a single-layer textile formed as a wearable garment with integrated textile electrodes and conductive traces connecting the electrodes to a controller unit configured in accordance with illustrative embodiments;

FIG. 1B is a photograph of an illustrative embodiment of the textile of FIG. 1A on a user;

FIGS. 1C to 1E are photographs of different views of the example textile of FIG. 1A and FIG. 1B on a mannequin;

FIGS. 2A and 2B are schematic illustrations of a wearable garments with conductive traces and electrode regions formed therein;

FIG. 3A is a schematic illustration of an example twist pattern of a hybrid yarn having a conductive wire around a nonconductive yarn;

FIG. 3B is a schematic illustration of an intarsia knitting technique for three separate regions of a single textile layer using three different yarns;

FIG. 4A is a schematic illustration of a flatbed knitting machine using the intarsia knitting technique for three separate regions of a single textile layer using three different yarns;

FIG. 4B is a schematic illustration of a flatbed knitting machine using the intarsia technique for separating a loop of conductive hybrid yarn from the end of a conductive trace in accordance with illustrative embodiments;

FIGS. 5A and 5B are front and back photographs of a single-layer textile produced with the intarsia knitting technique having four distinct regions formed using a distinct yarn in each region;

FIG. 6A is a photograph of a continuous textile section knitted using the intarsia technique and having a conductive trace region passing through a plurality of distinct regions of the textile section;

FIG. 6B is a photograph of a continuous textile section knitted using the intarsia technique and having a conductive trace region passing through an inert region from a first location to a second location;

FIG. 6C is a schematic illustration of a single-layer of a continuous textile section knitted having a conductive trace region passing through an inert region and electrically connected to an electrode region of the textile section;

to FIG. 6D is a schematic illustration is the continuous wires present in the conductive trace region of FIG. 6B;

FIG. 7A is a photograph of an embodiment of a knitted textile having conductive traces with loose ends of hybrid yarn extending from the conductive traces;

FIG. 7B is a photograph of the knitted textile of FIG. 7A with the loose ends having their conductive wires soldered to a corresponding copper wire of a wire assembly;

FIG. 8 is a photograph of a conductive trace region adjacent to an electrode region with a portion of the nonconductive fibers of the hybrid yarn of the conductive trace region having been removed using ablation to expose uninsulated portions of the conductive wire;

FIG. 9 is a photograph of a garment having conductive trace regions extending to electrode regions with a conductive material being applied to an ablated region of the conductive trace region adjacent to the electrode region to electrically couple the wires of the conductive trace region to the electrode region;

FIG. 10 is a photograph of an embodiment of a knitted textile having an integrated electrode and a conductive trace with a loose loop of the conductive trace extending across the face of the integrated electrode region;

FIG. 11 is a schematic illustration of a single-layer of a continuous textile section knitted using the intarsia technique and having a conductive trace region passing through an inert region and across a face of an electrode region;

FIGS. 12A-12E are photographs of an embodiment of the steps for coupling a conductive trace region of a knitted textile to an integrated electrode region of the knitted textile by ablating a portion of the conductive trace region that extends across the integrated electrode.

DETAILED DESCRIPTION

Certain exemplary embodiments will now be described to provide an overall understanding of the principles of the structure, function, manufacture, and use of the devices and methods disclosed herein. One or more examples of these embodiments are illustrated in the accompanying drawings. Those skilled in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments and that the scope of the present disclosure is defined solely by the claims. The features illustrated or described in connection with one exemplary embodiment may be combined with the features of other embodiments. Such modifications and variations are intended to be included within the scope of the present disclosure.
Example Textiles with Integrated Conductive Traces
FIG. 1A is a schematic illustration of a textile formed as a wearable garment with integrated electrodes and conductive traces connecting the electrodes to a controller unit configured in accordance with illustrative embodiments. Specifically, FIG. 1A schematically shows a textile garment 100 with integrated textile electrodes 130, and conductive traces 120 connecting the textile electrodes 130 to an electrical device 199. The garment 100 is constructed as a single textile layer to be worn directly against the skin. The garment 100 is knitted from a regular electrically inert material 110 (e.g., an insulator material, such as cotton, wool, or polyester) with the textile electrodes 130 knitted directly into the garment 100, without adding additional textile layers at the location of the textile electrodes 130. The conductive traces 120 are knitted with a hybrid yarn, discussed in more detail below, that is constructed from a strong and inelastic nonconductive yarn twisted with one or more conductive wires, with the conductive wires being coated with an insulating material. The hybrid yarn enables the conductive traces 120 to transmit power or electrical signals through the conductive wires without interference due to the insulating coating on the conductive wires. The textile electrodes 130 have an inner surface that is therefore positioned against the user's skin when the garment 100 is worn. The textile electrodes 130 are knitted from a conductive yarn, such as a silver coated polyester, that enables the textile electrodes 130 to conduct electrical signals across the textile electrode 130. The textile electrodes 130 are connected to the electrical device 199 via conductive traces 120 that are also knitted directly into the garment 100 without adding additional layers to the garment. In some embodiments, the garment 100 defines a single-layer knitted textile layer across the inert material 110, the textile electrodes 130, and the conductive traces 120. In some embodiments, the textile electrodes 130 are knitted as electrical connection regions for a sensor or electronic device affixed to the garment 100.
The textile electrodes 130 can be arranged to, for example, pick up or sense electrical signals from the user's body, such as those related to heart rate and heart function (e.g., the signals for use in forming an electrocardiogram EKG). In some embodiments, the garment 100 includes four textile electrodes 130, positioned with respect to the user's body in order to provide a high-quality EKG signal. The conductive traces 120 connect the textile electrodes 130 to the electrical device 199 via the conductive wires integrated into the hybrid yarn from which the conductive traces 120 are knitted. The conductive wire of the hybrid yarn can be coated with an insulating polymer, which is able to be removed at the points of contact with the textile electrodes 130 and the electrical device 199.
In some embodiments, the hybrid yarn is constructed from a highly inelastic material, such as meta-aramid or para-aramid (e.g., Kevlar® or Twaron®) or a material with similar material properties to protect the integrated conductive wires from damage or being severed during the knitting process and being damaged or severed during normal wear of the garment 100, such as Ultra High Molecular Weight Polyethene (UHMWPE), Polybenzimidazole (PBI), Polyphenylene Benzobisoxazole (PBO), High Strength Polyester, Liquid-Crystal Polymer (LCP), or spider silk. In some embodiments the hybrid yarn is made with a fire retardant and self-extinguishing material, such as para-aramid or material with similar properties according to the ASTM D6413/D6413M Standard Vertical Test Method for Flame Resistance of Textiles to enable the insulating layer and nonconductive yarn to be removed using ablation. The conductive wire can be, for example copper wire or copper-clad stainless-steel sire. Additionally, the textile electrodes 130 may be knitted or otherwise constructed with a conductive wire, such as silver or copper wire or a nonconductive yarn (e.g., nylon, polyester, cotton, or wool) coated with a conductive material such as silver or copper. In some embodiments, the standard material 110, textile electrodes 130, and conductive traces 120 are knitted together into a single-layer garment 100 without seams.
FIG. 1B is a photograph of an illustrative embodiment of the textile of garment 100 FIG. 1A on a user. FIG. 1B shows patches 130′ over the textile electrodes 130 that are arranged to maintain a moisture level in the textile electrode 130. These patches 130′ can also be used to impart stability to the textile electrode on body when the garment is worn and to reduce electrical static noise from the outer surface of the textile electrode 130. FIGS. 1C to 1E are photographs of different views of the example textile garment 100 of FIG. 1A and FIG. 1B on a mannequin.
While the embodiments discussed above include textile garments, other applications are readily considered within the scope of the single-layer textiles described herein. For example, vehicle seating with integrated sensors, flexible textile cables with conductive traces to transmit power or data through the textile cable, and straps or harnesses for securing devices or objects to the human body or to any other object.
FIGS. 2A and 2B are schematic illustrations of a wearable garments 150, 160 with conductive traces 120 and textile electrodes 130 formed therein. FIG. 2A shows a garment textile 150 with two pairs of textile electrode regions 130 each connected together by a conductive trace region 120. FIG. 2B shows a garment textile 160 with three pairs of textile electrode regions 130 each connected to a single central electrode region 139 via conductive trace regions. In operation, the garment textile 160 can have a centralized sensor or control unit 199 attached to the garment (e.g., in a pocket 140 knitted directly into the garment textile 160) and electrically connected to each of the textile electrode regions 130 by connecting directly with the single central electrode region 139. FIGS. 2A and 2B illustrate that textile embodiments of the present disclosure can be hardware. In the case of a garment textile 150, 160 for example, the construction of the textile layer can position the textile electrode regions 130 wherever either of a sensing region or an electrical connection is desired (e.g., is, hardware can move into different locations of the body.
Example Single-Layer Textile Knitting Techniques
Weaving is believed to be the most popular method of fabric construction used and has been known to mankind for over 3000 years. It involves interlacing yarns as a means to manufacture the fabrics. A woven structure has multiple yarns in warp (vertical) direction and one yarn in weft (horizontal) direction going from selvedge to selvedge (edge to edge). The yarns are interlaced at right angles to make a fabric structure. Woven textiles tend to be more dimensionally stable than knitted fabrics, having vertical threads interlaced with separate horizontal threads. However, interlaced construction techniques do not allow the conductive traces 120 and textile electrodes 130 to be seamlessly integrated into the single-layer garment 100, as shown in FIGS. 1A-2B, because in weaving techniques, for example, a weft yarn must always go from edge to edge (horizontally) and the warp yarns must always go from bottom to top (vertically). This means that any yarn, whether conductive or non-conductive, cannot change direction during the weaving process. For example, it is not possible for a woven weft yarn (horizontal) to change direction during weaving to in the warp direction (vertical). This means that for a conductive trace in the textile (e.g., conductive traces 120 of FIG. 1A) to be connected within the textile structure to an integrated textile electrodes (e.g., textile electrodes 130 show in FIG. 1A) the entire area of the woven textile, from the start of the conductive trace to the textile electrode, must be woven with the conductive yarns used to make the conductive trace.
In knitting, and particularly in flatbed weft knitting, it is possible for a yarn to change direction from weft to warp and back again (e.g., horizontal to vertical and back). This means it is possible to knit conductive traces 120 connecting textile electrodes 130 within a single knit textile layer with the shortest traces between two electrodes or between the conductive traces and an attached electrical device 199. Knitting, and specifically flatbed knitting, allows for the design of textile electrical circuits (e.g., conductive traces 120 connecting textile electrodes 130) with the shortest routes for the conductive traces and the placement of the textile electrodes 130 in the textile as needed for function. This is preferable as shorter conductive traces will be more efficient for data and power transfer. It is physically impossible to do the same thing in weaving.
While there are many knitting techniques that could be used to make a textile with the same shapes as the garments shown in FIGS. 1A-2B, as well as having different regions, intarsia knitting is the only knitting technique that can be used to make a textile garment 100 with the conductive traces 120 and the textile electrodes 130 integrated into a single continuous layer. Intarsia knitting can be achieved with circular weft knitting machines in a variation known as jacquard intarsia, but a preferred method is Intarsia using a flatbed knitting machine (such as those manufactured by Stoll, Shima Seiki and others). In flatbed knitting a carriage moves from side to side engaging with needles on a rectilinear knitting bed. Flatbed knitting can be achieved on a single knitting bed, a V-bed in which two knitting beds are arranged at an angle to each other, or Four-bed in which four beds are arranged opposing each other. The textile garment 100 of FIGS. 1B-1E were knitted using the intarsia techniques on a flatbed machine.
FIG. 3A is a schematic illustration of an example twist pattern of a hybrid yarn 200 having a conductive wire 220 around a nonconductive yarn 210. In order to knit the conductive traces 120 into a single-layer using a flatbed knitting machine the nonconductive yarn 210 must protect conductive wire 220 from being broken by the stresses put on the hybrid yarn 200 by the flatbed knitting machine. Accordingly, a hybrid yarn 200 was developed that was suitable for flatbed knitting. The hybrid yarn 200 is constructed from the nonconductive yarn 210 being twisted with the conductive wire 220, where the nonconductive yarn 210 is a strong and inelastic yarn that, when exposed to the tensile forces of the flatbed knitting machine, exhibits an elongation of a sufficiently small percentage to prevent breakage of the conductive wire 220. For example, the nonconductive yarn 210 can have a tensile strength greater than that of the conductive wire 220 as well as an elongation break percentage less than 5 or less than about 4.2. In other embodiments, the nonconductive yarn 210 may have a Young's modulus of 60 or greater. In practice, because the nonconductive yarn 210 and conductive wire 220 are twisted together and the nonconductive yarn 210 comprises the majority fraction of the overall cross-section of the hybrid yarn 200, the material of nonconductive yarn 210 need not simply be less elastic than the metal of conductive wire 220 because, as the hybrid yarn 200 is exposed to tensile forces, the hybrid yarn 200 acts as a single structure and the relative elasticity of the much larger nonconductive yarn 210 section is less than the relative elasticity of the much thinner conductive wire 220 as the hybrid yarn 200 undergoes tension. Accordingly, suitable embodiments of hybrid yarn 200 are constructed from very strong and inelastic fibers, such as meta-aramids and para-aramids, that are both thin and flexible enough to be knitted on a flatbed machine, but also strong and inelastic enough at those thin diameters to be twisted with a substantially thinner metal wire (e.g., a conductive wire 220 thin enough to maintain the thin and flexible properties of the overall hybrid yarn 200 that enable it to be both machine knittable and not affect the worn feeling of a garment) and prevent the substantially thinner metal wire from breaking.
FIG. 3B is a schematic illustration of an intarsia knitting technique for three separate regions of a single textile layer using three different yarns. FIG. 3B shows an inert region 110 knitted with an inert yarn 111, a conductive trace region 120 knitted with a hybrid yarn 200, and a textile electrode region 130 knitted with a conductive yarn 131.
FIG. 4A is a schematic illustration of a flatbed knitting machine 400 using the intarsia knitting technique for three separate regions 110, 120, 130 of a single textile layer using three different yarns. FIG. 4A shows an inert yarn 111 being knitted alongside a hybrid yarn 200 and a conductive yarn 131. FIG. 4B is a schematic illustration of a flatbed knitting machine using the intarsia technique for separating a loop of conductive hybrid yarn from the end of a conductive trace in accordance with illustrative embodiments.
FIG. 4B shows the flatbed knitting machine 400 with 540 separate needles on the front bed and 540 needles on the back bed separating a loop of conductive hybrid yarn 200 from the end of a conductive trace 120. In this example, once the conductive yarn is done knitting in its field, it continues to knit loosely on the back bed, every 10 needles or so, to hold down the loose tail of the yarn. The number of needles in use in this example were 400. When the 400th needle completed knitting the last stitch, the knitting machine kept knitting beyond the 400th needle, so that the yarn is held onto a single knitting needle that is beyond the knit area already completed. The number of empty needles between the 400^thneedle and the needle now holding the yarn can be any number and is only limited by the number of needles in the knitting bed. In this embodiment the number of needles is 10. The knitting carriage returns to the left-hand side of the knitting bed to complete the row in which the yarn was held outside the field of knitting. On the next row, the knitting carriage knits across the 400 needles and then travels to the needle holding the yarn and casts off the active stitch on that needle so that it is left hanging free of the needle bed. This cast-off stitch forms a loose loop free of the knit textile itself, and knitting continues across the 400 needles. This method of making a loose loop 123 can be used both at the end of a row of knitting whether at the edge of a knit textile (as shown in FIGS. 7A and 7B), or at the edge of an Intarsia field within the textile, such as being used to make multiple loose loops within the same textile (as shown in FIG. 6A).
FIGS. 5A and 5B are front and back photographs of a single-layer textile produced with the intarsia knitting technique having four distinct regions formed using a distinct yarn in each region. In FIGS. 5A and 5B independent yarns 710-713 are knitted into a desired pattern on the front of a textile. With the intarsia technique, the pattern of front is mirrored, without an inversion, on the opposite side. Specifically, each knitted field is independent, and their yarns 710-712 do not mix except for a single needle forming a loop stitch crossing 729 at the edges of each field. Unlike other multicolor techniques including Jacquard and Fair Isle, there is only one “active” color on any given stitch, and yarn is not carried across the back of the work; when a color changes on a given row, the previously knit yarn is left hanging. The hanging yarn is then picked up and knit in as the knitting carriage returns on the next row of knitting. This means that any intarsia piece generally is topologically several disjointed fields wherein each field can be knit with a different yarn. Intarsia is typically used with colored yarns; a simple blue circle on a white background involves one field of blue and two of white—one for the left and one for the right—or in illustrative embodiments: conductive and non-conductive yarn fields. This also means that textiles knitted with intarsia are lightweight and fluid because it is throughout only one fabric layer thick. In Fair Isle knitting, usually not more than two colors are used at once in a given row. Both yarns are carried all the way across the row, using whichever color is appropriate in the front, and the other color is carried loosely behind the worked stitches, creating a float or strand. Therefore, Fair Isle technique creates bulkier and heavy garments. Fair Isle does not permit the isolation of specific yarns within the garment, which is required the single-layer textiles discussed above, and therefore is not suitable for the construction textile such as a single-layer garment 100 with conductive traces 120 and textile electrodes 130 or any similar single-layer continuous knitted textile segment with conductive traces 120 and textile electrodes 130. Accordingly, the intarsia technique is well suited for constructing such a single-layer textile garment 100 with electrodes 130 and conductive traces 120 knitted into specific regions with the inert regions 110.
Example Single-Layer Knitted Textile Constructs with Conductive Traces
FIG. 6A is a graphic rendering of a continuous textile section knitted using the intarsia technique and having a conductive trace region passing through a plurality of distinct regions of the textile section. FIG. 6A shows multiple different yarns knitted into a single textile using the intarsia technique. FIG. 6A shows a conductive trace 120 knitted between a standard material 110 by way of knitting individual regions 180, 181, 182 around the conductive trace 120 in the standard material 110 to form the bends of the conductive trace 120. The conductive trace 120 terminates in loose loops 123 of hybrid yarn 200 that can, for example, be used to emetically connect a sensor or electronic device to the conductive trace 120. In some embodiments, the individual regions 180, 181, 182 are knitted from the standard material 110, and one or more of them could also be made from a different material, such as a conductive thread to form a textile electrode 130 in contact with the conductive trace 120.
FIG. 6B is a graphic rendering of a continuous textile section knitted using the intarsia technique and having a conductive trace region passing through an inert region from a first location to a second location. FIG. 6B is an example of the multi-region knitting of FIG. 6A, where all the regions 180, 181, 182 were knitted from the same material as the rest of the garment outside of the conductive trace 120 (i.e., the inert yarn 111). FIG. 6B shows a hybrid yarn knitted into a conductive trace 120 in an inert region 110 of a continuous textile section that change direction and provides an electrical connection between a first location (A) and a second location (B). This can, for example, enables the control device 199 of FIG. 1A to be connected to the conductive trace 120 at location (A) and provide an electrical connection to a textile electrode 130 at location (B) via the conductive wires 220 in the conductive trace 120 that extend continuously between (A) to (B).
FIG. 6C is a schematic illustration of a single-layer 301 of a continuous textile section 300 knitted to have a conductive trace region 120 passing through an inert region 110, with the conductive trace region 120 being electrically connected to a textile electrode region 130 of the textile section 300 at an interface 129 between the two regions. The single 301 defines a bottom side 305 and a top side 306 opposite the bottom side, with each region 110, 120, 130 extending between the top side 306 and the bottom side 305. Additionally, FIG. 6C shows a seal or patch 130′positioned on the top side 306 of the textile electrode region 130 as shown in FIG. 1B. FIG. 6D is a schematic illustration is the continuous wires 220 present in the conductive trace region 120 of FIG. 6B that extending between location (A) and location (B);
FIG. 7A is a photograph of an embodiment of a knitted textile having conductive traces 120 with loose ends of hybrid yarn 200 extending from each of the conductive traces 120 and FIG. 7B is a photograph of the knitted textile of FIG. 7A with the loose ends having their conductive wires 220 soldered 759 to a corresponding copper wire 759 of a wire assembly 750.
Examples of Connecting a Hybrid Conductive Yarn to a Textile Electrode
FIG. 8 is a photograph of a conductive trace region 120 adjacent to a textile electrode region 130 with a portion of the nonconductive fibers 210 of the hybrid yarn 200 of the conductive trace region having been removed using ablation to expose uninsulated portions 220′ of the conductive wire, where the ablation also removed the coating on a polymer conductive wire 220.
FIG. 9 is a photograph of a garment having conductive trace regions 120 extending through inert regions 110 to textile electrode regions 130 with a conductive material 923 applied to an ablated region of the conductive trace region 120 extending over the textile electrode region 130 to electrically couple (or improve the existing electrical connection between) the wires 220 of the conductive trace region 120 to the conductive yarn 131 of the textile electrode region 130.
FIG. 10 is a graphic rendering of an embodiment of a knitted textile having an integrated electrode region 130 and a conductive trace region 120 with a loose loop 123 of hybrid yarn 200 from the conductive trace region 120 extending across the face of the textile electrode region. The loop 123 can be cut into a tail in order to facilitate connection between the textile electrode 130 and the conductive trace region 120 of which the loop or tail is an extension of the same hybrid yarn 200. The loose loop 123 can be used to electrically connect the conductive trace region 120 to the textile electrode region 130 by removing the insulating layer (and, in some embodiments, the nonconductive yarn) from the loop 123 and connecting the now-bare conductive wire 220 of the loop 123 to the conductive yarn 131 of the electrode 130. Leaving this loop 123 loose allows the loop 123 to be ablated, exposing the bare conductive wire 210, without destroying the textile 100, 120, 130. In some embodiments, the loose loop 123 increases the surface area of the conductive wire 210 that can be connected to the textile electrode 130, as well as providing a free strand to more easily remove the insulating coating and nonconductive yarn 210.
FIG. 11 is a schematic illustration of a single-layer of a continuous textile section 301 knitted using the intarsia technique and having a conductive trace region 120 passing through an inert region 110 and across a face of an electrode region 130. The conductive trace region 120 includes a knitted extension 121 that is knitted out of the single layer of the continuous textile section to form a second layer above the textile electrode region 130. This knitted extensions 121 of the conductive trace region 120 can be electrically connected with the textile electrode region 130 as discussed in FIGS. 12A-12E.
FIGS. 12A-12E are photographs of an embodiment of the steps for coupling a conductive trace region 120 of a knitted textile to an integrated textile electrode region 130 of the knitted textile by ablating a knitted extension 121 of the conductive trace region 120 that extends across the integrated electrode. In FIG. 12A, the textile section 301 of FIG. 11 is positioned below a laser ablation rig with a protective structure 1201 (e.g., a thin metal plate) disposed between the knitted extension 121 and the textile electrode region 130 to allow a portion of the knitted extension 121 to be ablated without damaging the textile electrode region 130. FIG. 12B shows the bare conductive wire 220′ exposed in the portion of the knitted extension 121 that was ablated. In FIG. 12C, a conductive adhesive or similar conductive material 123 has been placed in and around the region of the knitted extension 121 with the bare conductive wire 220′ to electrically connect the conductive wire 220 of the conductive trace region 120 with the textile electrode region 130. In FIG. 12D, a sealing film 1360 has been placed around the conductive material 123 to protect it and seal it from the surrounding textile layers 120, 130. In FIG. 13E, an outer sealing patch 1340 is placed around the entire textile electrode region 130 to create a moisture barrier between the textile electrode region 130 and the rest of the textile. In some instances, a reservoir material is also placed between the textile electrode region 130 and the outer sealing patch 1340 to retain moisture in the textile electrode region 130 and maintain the sensing performance of the textile electrode region 130 as the textile remains against the skin.
The embodiments of the invention described above are intended to be merely exemplary; numerous variations and modifications will be apparent to those skilled in the art. One skilled in the art will appreciate further features and advantages of the disclosure based on the above-described embodiments. Such variations and modifications are intended to be within the scope of the present invention as defined by any of the appended claims. Accordingly, the disclosure is not to be limited by what has been particularly shown and described, except as indicated by the appended claims. All publications and references cited herein are expressly incorporated herein by reference in their entirety.

Claims

What is claimed is:

1. A textile, comprising:

a single knitted layer comprising an inert region and a conductive trace region knitted together to form a continuous textile section of the single knitted layer,

wherein the inert region is knitted using an electrically inert yarn, and

wherein the conductive trace region is knitted from a hybrid yarn containing a non-conductive yarn twisted with a conductive wire, the conductive wire having an exterior layer of an insulating material.

2. The textile of claim 1,

wherein the conductive trace region is configured to transmit an electrical data or power signal along the single knitted layer via the conductive wire from a first location in the continuous textile section to a second location in the continuous textile section.

3. The textile of claim 2,

wherein the conductive wire of the conductive trace region between the first and second locations comprises one or more continuous lengths of the conductive wire spanning the first and second locations.

4. The textile of claim 2,

wherein the conductive trace region is configured to transmit an electrical data or power signal along the single knitted layer via the conductive wire from a first region of the conductive trace region where the exterior layer has been removed from the conductive wire to a second region of the conductive trace region where the exterior layer has been removed from the conductive wire.

5. The textile of claim 1,

wherein the single knitted layer further comprises an electrode region knitted using a conductive yarn, the conductive yarn comprising an exposed exterior surface of an electrically conductive material.

6. The textile of claim 5,

wherein a portion of a boundary of the electrode region is knitted together with an adjacent portion of a boundary of the conductive trace region.

7. The textile of claim 6,

wherein the exterior layer of the conductive wire of the conductive trace region adjacent to the electrode region is removed and the conductive wire contacts the conductive yarn such that the conductive trace region is electrically connected with the electrode region.

8. The textile of claim 5,

wherein a second layer of the hybrid yarn is knitted of the conductive trace region of the continuous textile section and over a portion of the electrode region to form a two-layer section of the textile, and

wherein the exterior layer of the conductive wire of a portion of the conductive trace region in the two layer section is removed to expose a portion of the conductive wire and the exposed portion of the conductive wire is electrically connected with the electrode region via a conductive material.

9. The textile of claim 5, comprising a section of the hybrid yarn of the conductive trace region extending out of the continuous textile section such that the section of the hybrid yarn can extend across a portion of the electrode region.

10. The textile of claim 1,

wherein the single-layer defines a first surface and a second surface opposite the first surface, and wherein a yarn of a given region of the single-layer is presented at both the first and second surfaces.

11. The textile of claim 1,

wherein the hybrid yarn comprises the non-conductive yarn twisted with two separate conductive wires each having an exterior layer of the insulating material.

12. The textile of claim 1,

wherein the conductive wire of the hybrid yarn defines a continuous length of conductive wire along each length of hybrid yarn of the conductive trace region.

13. The textile of claim 1,

wherein the non-conductive yarn of the hybrid yarn comprises at least one of an aramid, meta-aramid, or para-aramid polyamide fiber.

14. The textile of claim 1,

wherein the conductive wire of the hybrid yarn comprises an exterior surface of a conductive metal and the insulating material comprises a polymer.

15. The textile of claim 1, wherein the single-layer is knitted using a single-layer intarsia technique having all regions in the single-layer.

16. The textile of claim 1, wherein the knitted textile is a garment and the inner surface of the single knit layer defines a skin-facing side of the garment and an outer surface of the single knit layer defines an exterior surface of the garment.

17. A method of knitting a textile, the method comprising:

knitting a single-layer of the textile from an electrically inert yarn and a hybrid yarn to form a continuous textile section by:

knitting the electrically inert yarn into an inert region of the single-layer, and

knitting the hybrid yarn into a conductive trace region of the single-layer,

wherein the hybrid yarn comprises a non-conductive yarn twisted with a conductive wire, the conductive wire having an exterior layer of an insulating material.

18. The method of claim 17,

wherein the conductive trace region is knitted to transmit an electrical data or power signal along the single knitted layer via the conductive wire from a first location in the continuous textile section to a second location in the continuous textile section.

19. The method of claim 18,

wherein the conductive wire of the conductive trace region knitted between the first and second locations comprises one or more continuous lengths of the conductive wire spanning the first and second locations.

20. The method of claim 17, further comprising:

removing the exterior layer of the conductive wire in a first region of the conductive trace region, and

removing the exterior layer the conductive wire in a section region of the conductive trace region,

wherein the first and second regions are connected via a continuous section of the conductive trace region, and

wherein the continuous section of the conductive trace region is configured to transmit an electrical data or power signal along the continuous textile section via the conductive wire from the first region to the second region.

21. The method of claim 20,

wherein removing the exterior layer of the conductive wire in at least one of the first or second regions comprises ablating the hybrid yarn to remove the non-conductive yarn and the exterior layer on the conductive wire.

22. The method of claim 17, further comprising:

knitting the single-layer of the textile with a conductive yarn, the conductive yarn being knit into an electrode region of the continuous textile section,

wherein the conductive yarn comprises an exposed exterior surface of an electrically conductive material.

23. The method of claim 22,

24. The method of claim 23, further comprising:

removing the exterior layer of the conductive wire of the conductive trace region adjacent to the electrode region such that the conductive wire contacts the conductive yarn and the conductive trace region is electrically connected with the electrode region.

25. The method of claim 22, further comprising:

knitting a second layer of the hybrid yarn out of the conductive trace region of the continuous textile section and over a portion of the electrode region to form a two-layer section of the textile,

removing the exterior layer of the conductive wire of a portion of the conductive trace region in the two layer section is removed to expose a portion of the conductive wire, and

electrically connecting the exposed portion of the conductive wire with the electrode region via a conductive adhesive.

26. The method of claim 25, wherein removing the exterior layer of the conductive wire in the two layer section comprises:

positioning a protective material between the first layer and the second layer, and

ablating the hybrid yarn in the second layer to remove the non-conductive yarn and the exterior layer on the conductive wire, the protective material preventing ablation of the electrode region.

27. The method of claim 17, further comprising:

extending a section of the hybrid yarn of the conductive trace region extending out of the continuous textile section such that the section of the hybrid yarn can extend across a portion of the electrode region.

28. The method of claim 17,

29. The method of claim 17,

30. The method of claim 17,

31. The method of claim 17,

32. The method of claim 17,

33. The method of claim 17,

wherein the single-layer is knitted using a single-layer intarsia technique having all regions of the single-layer in the same intarsia layer.

34. The method of claim 33,

wherein the single-layer is knitted using a single bed of a knitting machine.

35. The method of claim 33,

wherein each yarn of the single-layer is knit separately.

36. The method of claim 17,

wherein the textile is a garment and the inner surface of the single knit layer defines a skin-facing side of the garment and an outer surface of the single knit layer defines an exterior surface of the garment.