DESC:TECHNICAL FIELD OF THE INVENTION
The present invention relates to a methods and system for integrating lighting systems onto flexible substrates and products made from such materials like garments, shoes, seating, home furnishing, protective clothing etc.

BACKGROUND OF THE INVENTION
Electroluminescence (EL) is an optical and electrical phenomenon in which a material emits light in response to the passage of an electric current or to a strong electric field. These materials are generally referred to as phosphors and generate single or multiple colors of varying intensity based on the electrical input. Unlike light emitting diodes (LEDs) the EL phenomenon does not produce heat but needs a specific driving circuit to work. EL provides an advantage as it can be made in to a thin flat surface, referred to as EL panel or stripes or even a thin strand called EL wire. A typical EL system needs an EL lighting component (panel, strip, and/or wire), driver for EL and a power source. EL drivers may have functionality for changing intensity and blink rate / type of emission (color).
Lighting gives an attractive visual effect and addition of lighting in textile-based applications has been surging at present. LED lighting has been used for aesthetic or functional applications in textile-based products. US5249106A (lapsed) claims use of LED lighting for illuminating protective clothing so that a user can be easily identified in a visually difficult environment. US 9483918 B2 describes the use of LED patterns for personal illumination. LEDs have also been used in shoes, fashion accessories, and clothing.
In contrast to LEDs, EL material can provide sufficient light production with relatively flexible forms and with lower power consumption. EL has been gaining use in textile-based applications, shoes, fashion accessories and clothing. CN206213362 U mentions use of EL based systems as an alternative to reflective tapes for illumination used in protective clothing.
EL wires woven into fabrics have been used in architectural application US20040047142A1. Specifically, in clothing and footwear, many EL applications are carried out via EL strips and panels attached to textile via, stitching, Velcro, magnets, adhesives, and the like. Other clothing-based applications include the use of EL wire stitched on the edges or put into a piping or attached through adhesives to the fabric/garment. US8952610B2 discloses printing of EL on to textile substrates.
Although, there have been many patents/patent applications on using EL on textile and related products, none of them have been able to standardize a process for manufacturing at industrial level. Gluing of EL wires in various patterns physically without an automated process may result in non-uniform products due to manual error and further also includes excessive labor costs. Embedding EL wire in cloth piping or tubing restricts the usage of the cloth or garment thereof, and direct light exposure results in a dimmer glow.
Typically, sewing of EL wire is achieved by laying the EL wire is on a textile substrate and hand tacking / sewing with a separate needle and thread. But such an operation again brings human interference which leads to variation from product to product and cannot give a good finish to the product. Moreover, such process increases Labor costs a low manufacturing rate and also requires skilled labour. Also, as EL wires are stiff, they cannot be used on an embroidery machine to make patterns on the textile and related substrates.
Therefore, there is a need for methods and systems which alleviate some of the problems associated with non-uniform attachment of EL wires to flexible textile-based articles/shoes/fashion accessories.

SUMMARY OF THE INVENTION
In one aspect, the invention provides an attachment for an embroidery machine for integration of Electroluminescence (EL) wire on to the substrates. The attachment includes a spool for reel of EL wire, a tensioning device for relieving and maintaining tension in the EL wire, a laying head for laying the EL wire on a substrate based on the predetermined design, a ring rotating about its axis to feed the EL wire to the laying head without a twist and a controller to control the laying head based on the predetermined design pattern and operate the attachment in conjunction with the system to stitch the EL wire with a yarn.
In another aspect, the present invention provides a system for integration of EL wire on to a substrate. The system includes the attachment having the spool, the tensioning device, the laying head and the ring. The embroidery machine includes the stitching head. The ring is mounted around the laying head and a stitching head of the embroidery machine for laying the EL wire without twist on to the substrate based on a predetermined embroidery design.
In yet another aspect, the present invention provides a method for integration of EL based products on to the substrates. In first step, a design pattern to be made on to a substrate is defined. In next step, an EL wire is wound parallelly on a double flanged spool mounted on a positively driven spindle of a creel. In the next step, the first end of the EL wire is sealed with a transparent heat shrink or insulating adhesive In the next step, the EL wire is passed through a tensioning device having zig-zag path. In the next step, the EL wire is passed through an eyelet between two rings which are mounted around a sewing head and a laying head. In the last step, the EL wire is bound to the substrate by stitching yarn over the laid wire.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows various patterns for stitching EL wire according to the present invention;
FIG 2 is a schematic representation of an attachment of EL wire on a substrate according to a design of the present invention;
FIG 3 is a schematic representation of an attachment of an EL wire system on a textile substrate according to the present invention;
FIG 4 shows EL wire based continuous designs for (a) fashion and (b) home furnishing according to the present invention; and
FIG 5 shows an example of an EL wire based safety light design for personal protective clothing according to the present invention.

DESCRIPTION OF THE INVENTION
All materials used herein were commercially purchased as described herein or prepared from commercially purchased materials as described herein.
Described herein are attachment and methods that provide uniform and reproducible, mechanized and automated, manufacturing techniques to attach EL wires to flexible substrates such as textile, leather, textile-based products like garments, home furnishing and the like. The attachment of EL wire to the substrates using the techniques described herein allows for uniform appearance in products and large scale manufacturability.
Described herein are systems and methods for integration of EL based products on to the substrates to obtain uniformity, repeatability, design flexibility, and quality finish in front and back of substrates and a mass production technique for commoditizing the finished products.
In an embodiment, provided herein is a method for integration of EL based products on to the substrates includes steps of defining a design pattern to be made on to the substrate as shown in FIG. 1, laying EL wire (106) via a laying head (110) which lays the wire on the textile substrate according to the predefined design pattern, simultaneously binding the EL wire (106) to the substrate by stitching yarn over the laid wire (106) by a stitching head (112) following the laying head (110) of the EL wire (106).
According to an embodiment, the stitching head (112) moves over the laid wire in various patterns to bind the EL wire (106) to the substrate ensuring a definite placement of EL wire (106) as per the desired pattern. According to an embodiment, the method includes step of sealing of first end (106A) of the EL wire (106) with a transparent heat shrink or insulating adhesive so that the two conducting wires within the EL wire (106) are not shorted. This seal ensures water proofing of the EL wire (106) at the starting end (106A). The insulated and sealed first end (106A) is then laid and stitched.
Referring to FIG. 2 and 3, in accordance with an embodiment, an attachment (100) to connect to an embroidery machine (113) for carrying out the method for integration of EL wire (106) on to the substrates (102) is shown. The embroidery machine (113) includes a table (104) to move a substrate (102) in X-Y directions. The attachment (100) includes a spool (107) for reel of EL wire (106), a tensioning device (108) to relieve and maintain tension in the EL wire (106), a laying head (110) for laying the EL wire (106) on a substrate (102) based on the predetermined design; a ring (114) to be mounted around the laying head (110), a controller (116) and a stitching head (112) of the embroidery machine (113).
In accordance with this one embodiment, the ring (114) rotates about its axis to feed the EL wire (106) to the laying head (110) without a twist wherein the laying head (110) lays the EL wire (106) onto a substrate (102) based on a predefined design pattern. The controller (116) controls the laying head (110) based on the predetermined design pattern and operate the attachment (100) in conjunction with the embroidery machine (113) to stitch the EL wire (106) with a yarn as soon as the EL wire (106) laid on the substrate (102) by the stitching head (112) of the embroidery machine (113) following the laying head (110) of the EL wire (106).

In accordance with an embodiment, the laying head (110) also moves in a zig-zag way to clear the EL wire (106) of the path of stitching head (112) then ensuring that the EL wire (106) is not pierced by the needle. The spool (107) is mounted on a positively driven spindle (107) for positively feeding the EL wire (106) for laying and sewing operation. According to an embodiment, the yarn is a transparent monofilament yarn made from polyester or a fine monofilament of PA, PET, PP, PE and related polymer having 0.1 mm to 0.3 mm diameter.In accordance with an embodiment, the substrate includes textiles, leather, foam, polymer sheets and products made from such materials including garments, shoes, seating, home furnishing, protective clothing. However, it is understood here that other suitable material may be used in alternative embodiment of the present invention.
Referring to FIG. 3 the attachment (100) on a textile substrate (102) is shown., FIG. 4 shows EL wire based continuous designs for (a) fashion and (b) home furnishing according to the present disclosure and FIG. 5 shows an example of an EL wire (106) based safety light design for personal protective clothing according to the present disclosure. According to an embodiment, the predetermined design patterns are continuous without sharp edge or non-continuous including sequential design for including sharp edges or giving a motion effect.
In accordance with an embodiment, the system for integration of Electroluminescence (EL) wire (106) on to a substrate (102) includes the attachment (100) having the spool (107), the tensioning device (108), the laying head (110), the ring (114) and the embroidery machine (113) having a stitching head (112). The ring (114) is mounted around a laying head (110) and a stitching head (112) of the embroidery machine (113) for laying the EL wire (106) without twist on to the substrate (102) based on a predetermined embroidery design.
According to an embodiment, EL wire (106) at (starting) first end (106A) and EL wire at (ending) second end (106B) of the design pattern is stitched with a high stitch density than the EL wire (106) between the starting and ending of the design pattern. The high density stitching and the length of the high density stitching depend upon the diameter of the EL wire (106). Preferably high density stitching is 40 – 55 stitch per inch and the length of the high density stitching is 2 – 4 mm. The high density stitching for 2-4 mm of first end (106A) and second end (106B) of stitch ensures locking of the starting point on to the substrate and prevents any opening of stitching thread during product usage. The second end of the EL wire (106B), after the design stitching is complete, is passed through the substrate to the back of the substrate (102).
Various design can be made such as Brand Logo, outline to an existent normal embroidery design, sequential designs to give motion effect, warning symbols. Stitching patterns over the laid EL wire (106) vary and depend on the design of the laid EL wire (106), the substrate (102) used and the wire dimensions. Various patterns of stitching shown in FIG. 1 include and are not limited to zigzag with single stitching path (1a), zigzag with single or double additional thread to increase the bind strength and have a broken line effect (1b), zigzag with dual stitch path on both side of the laid yarn for thicker wire (1c), stitch line on one side of the wire with loop thread going over the wire for thicker wire and heavy substrate (1d).
According to the method, the EL wire (106) is parallelly wound on a double flanged spool (107) mounted on a positively driven spindle (107) of the creel. The EL wire (106) then passes through a tensioning device (108) having zig-zag path. This tensioning device (108) provides feedback to the spindle (107) to positively feed the EL wire (106) when necessary.
The EL wire (106) passes through an eyelet between a pair of rings (114) which are mounted around the stitching head (112) and the laying head (110). This ring (114) can rotate on its axis and ensures that the EL wire (106) is fed to the laying head (110) without getting twisted and is clear from the path of stitching head (112). As the position of laying head (110) change according to design the ring (114) rotates and follows the laying head (110).
The EL wire (106) then passes through an eyelet on the laying head (110) which moves per the design requirement. The laying head (110) can only move around the stitching head (112). The stitching head (112) which is the central part of the whole assembly can rotate on its axis to stitch the EL wire (106) which is guided in different direction based on the predetermined design pattern. The stitching head (112) is fed with a transparent monofilament yarn. The sewing yarn placed in the creel passes through a swinging arm tensioning device (108) as present in the conventional sewing machine. The yarn is then threaded through the needle. Below the fabric a bottom bobbin yarn arrangement is mounted in the machine table (104). This yarn engages with the top needle yarn to create a lock stitch. The bobbin yarn holder has a polyester non-transparent sewing thread.
The substrate on which the EL yarn to be stitched is lay flat on a table (104) of the embroidery machine (113) which moves in both X & Y direction according to the design. The combined lateral movement of fabric table (104) and rotary movement of stitching head (112) along with laying head (110) helps in creating the predefined design patterns.
Once the starting position of the design is fixed by fabric table (104) movement the laying head (110) comes to its place and the sewing is started. The stitch density is kept high for a stitching at the starting of the design pattern or first end of EL wire (106) for 2 to 4 mm. Then onwards stitching is done at 8 – 12 stitches per inch. The laying and stitching continues as per the design and at the end of the design pattern or second end of the EL wire (106B), the stitch density is again increased to 2 – 4 mm. Once done the stitching head (112) makes the locking stitch to prevent unraveling of sewing yarn and then cuts the sewing thread. The EL wire (106) can also be cut automatically, manually or can be kept uncut for the next design. Cutting results in a trailing end of EL yarn.
Once the substrate (102) with design is removed from the machine. The first and second end (106A), (106B) are passed on to the back of fabric (102) through a small hole which can be done manually with scissor or through a more secure button hole done on a button hole creation machine. The substrate (102) with EL wire (106) thus obtained is cut into a desired garment piece pattern and stitched into a garment.
The leading end of the EL wire (106) is trimmed and sealed with a transparent polyolefin heat seal lined with adhesive. This is done through hot air gun. The trailing end of EL wire (106) is connected to the power source (115). The PVC coating is first peeled and the two terminals are connected to an EL driver (118) via soldering and insulated with a heat shrink. The EL wire driver (118) controls the sequence, timing, pattern and brightness of the EL wire (106). The EL driver (118) is an electronic device in a casing. Shown in FIG. 3 EL driver (118) with wireless communication Thus, the EL wire (106) can be lit in a sequence, for certain period of time with any blinking patterns at various brightness which is either pre-programmed on to a chip in the EL driver (118) or is communicated to the EL driver (118) via a wireless signal (BLE Wi-Fi) based on user inputs or sensor (119) (brightness sensor, noise level sensor, direction sensor)
The EL driver (118) used herein may be powered by non-rechargeable or rechargeable batteries or solar means. These batteries may be the standard ones available in market or thin flexible batteries with large surface area stitched directly on to the fabric and connected to EL driver (118) via wires, conductive traces, conductive threads etc. The EL driver (118) may also be powered by connecting it to a mobile phone (121) via a cable hidden in seams or clothing and an attachment port opening inside the pocket. Where the EL wire (106) is required to be luminescent for a longer period of time (e.g., for home furnishings), the EL wire may also be powered via an external AC source (115) and an EL driver (118) designed for AC power sources (115). Alternatively, the EL wire (106) can be powered from a piezo based system (120) which lights the EL wire (106) whenever there is any motion in the garment due to user movement. The piezo based system (120) may comprise of thin film piezo electric material stitched on to substrate or piezo based substances coated or laminated on to the substrate. The power generated due to the piezo electric material can either directly be delivered to an EL driver (118) after regulation or can be used to recharge the batteries supplying wire to EL wires (106). The EL driver (118) in case of garments can be well hidden in a secret pocket or used as a garment accessory like button, buckle etc.
Rechargeable batteries can be charged using wireless charging systems consisting of an antenna and suitable circuitry which is laminated on to the substrate or solar means. Multicolor EL can be used to obtain various design effects. In another variation the EL wire (106) can be attached on a thick soft substrate like velvet, pile fabric or foam. This results in the EL wire (106) penetrating inside the substrate and only light being visible emerging from the crevices. The attachment of EL wire (106) can be either done on a readymade garment using the above described process. The attachment process can also be done on a fabric pattern piece which is ready to be sewn into a garment or can be done on to a raw fabric which can be then processed to make a garment or used in home furnishing application.
The EL driver (118) acts as a power source and also as a programmer for the light glow pattern. EL driver (118) has a BLE microcontroller functionality so that can connect to user’s smart phone (121) or BLE beacon nearby to transmit specific lighting signals. The EL driver (118) can be battery driven or powered via OTG cable from user’s smart phone (121) or a battery pack kept in users pocket.
The invention has been described in detail with reference to preferred embodiments thereof. However, it will be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles of the invention, the scope of which is defined in the appended claims and their equivalents.

,CLAIMS:
1. An attachment (100)for an embroidery machine (113) for integration of Electroluminescence (EL) wire on to the substrates, the attachment (100) comprising:
a spool (107) for reel of EL wire (106);
a tensioning device (108) for relieving and maintaining tension in the EL wire (106);
a laying head (110) for laying the EL wire (106) on a substrate (102) based on the predetermined design;
a ring 114 rotating about its axis to feed the EL wire (106) to the laying head (110) without a twist; and
a controller (116) to control the laying head (110) based on the predetermined design pattern and operate the attachment in conjunction with the system to stitch the EL wire (106) with a yarn.

2. The attachment (100) as claimed in claim 1, wherein the embroidery machine (113) having a table (104) to move the substrate in X-Y directions.

3. The attachment (100) as claimed in claim 1, wherein the laying head (110) moves in a zig-zag way to prevent EL wire (106) coming in the way of sewing needle.

4. The attachment (100) as claimed in claim 1, wherein the spool (107) is mounted on a positively driven spindle (107) for positively feeding the EL wire (106) for laying and sewing operation.

5. The attachment (100) as claimed in claim 1, wherein the yarn is a transparent monofilament yarn having 0.1 mm to 0.3 mm diameter.

6. The attachment (100) as claimed in claim 5, wherein the transparent monofilament is made from polyester or a fine monofilament of PA, PET, PP, PE and related polymer.

7. The attachment (100) as claimed in claim 1, wherein the substrate (102) includes textiles, leather, foam, polymer sheets.

8. The attachment (100) as claimed in claim 7, wherein the substrate (102) includes garments, shoes, seating, home furnishing, protective clothing and the like made from textiles, leather, foam, polymer sheets.

9. A system for integration of Electroluminescence (EL) wire on to a substrate, said system comprising
an attachment having a spool (107), a tensioning device (108), a laying head (110) and a ring (114) as claimed in one of the preceding claims 1-9; and
an embroidery machine (113) having a stitching head (112);
wherein the ring (114) is mounted around a laying head (110) and a stitching head (112) of the embroidery machine (113) for laying the EL wire (106) without twist on to the substrate (102) based on a predetermined embroidery design.

10. The system as claimed in claim 9, wherein the EL wire (106) laid on the substrate (102) by a stitching head (112) of the embroidery machine (113) is followed by the laying head (110) of the EL wire (106).

11. A method for integration of EL wire on to the substrates by the system as claimed in claims 1-10, comprising steps of:
defining a design pattern to be made on to a substrate (102);
wounding an EL wire (106) parallelly on a double flanged spool (107) mounted on a positively driven spindle (107) of a creel;
sealing of first end (106A) of the EL wire (106) with a transparent heat shrink or insulating adhesive;
passing of the EL wire (106) through a tensioning device (108) having zig-zag path;
passing of the EL wire (108) through an eyelet between two rings (114) which are mounted around a stitching head (112) and a laying head (110); and
binding the EL wire (106) to the substrate by stitching yarn over the laid wire (106).

12. The method for integration of EL wire on to the substrates as claimed in claim 11, wherein the predetermined design patterns are continuous without sharp edge or non-continuous including sequential design for including sharp edges or giving a motion effect.

13. The method for integration of EL based products on to the substrates as claimed in claim 11, wherein the laying head (110) moves around the stitching head (112).

14. The method for integration of EL based products on to the substrates as claimed in claim 11, wherein the a stitch density is from about 8 to about 12 stitches per inch excluding 2-4 mm from first end (106A) and second end (106B) of the EL wire (106).

15. The method for integration of EL based products on to the substrates as claimed in claim 11, wherein the a stitch density is from about 40 to about 55 stitches per inch for 2-4 mm of first end (106A) and second end (106B) of the EL wire (106).

16. The method for integration of EL based products on to the substrates as claimed in claim 11, wherein the sequence, timing, pattern and brightness of the EL wire (106) is controlled by an EL driver (118).

17. The method for integration of EL based products on to the substrates as claimed in claim 15, wherein the EL driver (118) has a BLE microcontroller functionality to connect to user’s smart phone (121) or BLE beacon in near proximity.