Patent Publication Number: US-2023151517-A1

Title: Sock and a method of knitting a sock

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present non-provisional patent application is related to U.S. Provisional Patent Application No. 63/116,325 filed Nov. 20, 2020 and incorporates the contents thereof in full. 
    
    
     FIELD OF THE INVENTION 
     The present disclosure is in the field of foot apparel. More particularly, the present disclosure provides systems and methods of constructing a sock with a polymer, elastomeric material, polyurethane, or gel patch or pad between an outer layer and an inner layer to create a cushioned sock at the ball and heel of the foot, the patch or pad encapsulated between the outer and inner layers. 
     BACKGROUND 
     The ball and heel of the human foot support a significant amount of total body weight. When walking, running, climbing, and carrying objects, the ball and heel bear even greater weight. Ankle, knee, back, and neck pain can be reduced by using quality footwear that provides cushioning and protection. Such footwear includes socks in addition to shoes. A sock of high quality absorbs perspiration and also keeps the foot warm. 
     SUMMARY 
     A sock and method of knitting a sock such that a gel or elastomeric polymer such as silicone is sandwiched between an outer and inner layer and whereby the sock is knit in one continuous tube or cylinder and that when folded upon itself creates a double layer with the purpose of covering the adhered polymer between outer and inner layers. The polymer is sandwiched or surrounded by yarn, fiber, or thread layers. The polymer is provided in the form of two pads or patches that provide cushioning for the foot and may extend the life of the sock. Various manufacturing systems and methods are provided herein, all based on an several common underlying principles. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG.  1    is a block diagram of a system of a double-layered sock containing polymer pads cushioning the ball and heel of the foot according to an embodiment of the present disclosure. 
         FIG.  2    is a diagram of a system of a double-layered sock containing polymer pads cushioning the ball and heel of the foot according to an embodiment of the present disclosure. 
         FIG.  3    is a block diagram of a system of a double-layered sock containing polymer pads cushioning the ball and heel of the foot according to an embodiment of the present disclosure. 
         FIG.  4    is a diagram of a system of a double-layered sock containing polymer pads cushioning the ball and heel of the foot according to an embodiment of the present disclosure. 
         FIG.  5    is a diagram of a system of a double-layered sock containing polymer pads cushioning the ball and heel of the foot according to an embodiment of the present disclosure. 
         FIG.  6    is a diagram of a system of a double-layered sock containing polymer pads cushioning the ball and heel of the foot according to an embodiment of the present disclosure. 
         FIG.  7    is diagram of a system of a double-layered sock containing polymer pads cushioning the ball and heel of the foot according to an embodiment of the present disclosure. 
         FIG.  8    is a diagram of a system of a double-layered sock containing polymer pads cushioning the ball and heel of the foot according to an embodiment of the present disclosure. 
         FIG.  9    is a diagram of a system of a double-layered sock containing polymer pads cushioning the ball and heel of the foot according to an embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Systems and methods described herein provide for producing a double-layered sock made from a single tube of fabric or yarn or from two separate tubes in which pads or cushions are positioned between two layers and are not visible to a user. A first pad is positioned at a ball area of the user&#39;s foot and the second pad is positioned at the heel area. The pads provide cushioning and comfort for the user at points where the user&#39;s weight rests most heavily. The pads may also extend the useful life of the double-layered sock. 
     The sock is produced from a single continuous tube of fabric that is folded into itself to form two layers or from two separate layers that are joined similarly. A first side or half of the tube is folded over to completely envelop a second side or half. As the far end or circumference of the first half is pulled over and completely encases the second side, the second side may be pulled through the interior of the first side. The result of this action is a double-layered cylinder where one end must be sewn to close either a toe section or finalize a welt area at the top of the sock depending on placement of the silicone pads. 
     Prior to the folding and enveloping action described above, the two silicone pads are placed on the side or half of the fiber tube that is closed over atop the other side or half. The side holding the pads, once folded over, then faces inward to the outward facing surface of the other side. The toe or welt section may then be sewn depending on the original placement of the pads as provided in separate but similar embodiments provided below. 
     The two pads are affixed to the fabric with adhesive. Silicone gel is mixed with 3% of its catalyst. Silicon is filled into a brass metallic mold in which a designed grid is engraved using a computer numerically controlled (CNC) machine. The mold is placed on the pattern knitted in the inner layer of the sock. The mold is compressed in double platted compression machine. Heat of an upper plate is set to 105° C., and heat of a lower plate is set to 95° C. under air pressure of 2 HP for two minutes and 20 seconds. 
     Once the first half or side is folded and closed over atop the second half or side, the double-layer sock with silicone pads affixed within is stretched over a foot form. The form is passed through temperature of 160° C. for 20 seconds and applied air pressure of 2 HP. 
     Systems and methods provide that the two halves of the fabric tube become the two layers of the double-layer sock. Because the two halves begin as a single continuous fabric tube and are not physically cut or separated, each of the two halves effectively comprises one of the two layers of the sock. Before folding, the two layers are joined at either a toe area or a welt area as is discussed in detail below in conjunction with the figures. 
     Turning to the figures,  FIG.  1    is a block diagram of a system of a double-layered sock.  FIG.  1    depicts components of a system  100  of a sock and a method knitting a sock as provided herein. 
     As noted, the double-layered structure of the sock is made possible by folding one half of a fabric tube or cylinder that is holding two silicone pads over the other half of the tube. The present disclosure provides for two embodiments which may be easier for an observer to understand by viewing  FIG.  2    that provides detail for  FIG.  1    and by viewing  FIG.  4    that provides detail for  FIG.  3   . As  FIG.  2    and  FIG.  4    illustrate, the two halves, that when united by the folding or enveloping process to become the double-layered sock, appear beforehand to be two individual socks joined at either the welt or toe.  FIG.  2    and  FIG.  4    are provided as they may guide a viewer in examining  FIG.  1    and  FIG.  3   , respectively, where the basic components provided herein are enumerated. 
       FIG.  1   , which as noted corresponds to  FIG.  2   , provides the system  100  which comprises a fiber tube  102 , a left half  104 , a right half  106 , a left end  108 , and a right end  110 . The system  100  also comprises a first patch  112 , a second patch  114 , a center point  116 , a left welt  118 , and a right welt  120 . 
     The two halves  106 ,  108  in  FIG.  1    are connected at the center point  116  near the welts  118 ,  120  as can be seen clearly in  FIG.  2   . The first patch  112  is affixed to the left half  104  about two inches from the left end  108  which is the toe area. The first patch  112  supports the ball of the user&#39;s foot. The second patch  114  is affixed to the left half  104  about six inches to the right of the first patch  112  and support to user&#39;s heel. 
     After the patches  112 ,  114  are firmly affixed to the left half  104 , the left half  104  is pulled over the right half  106  in an enveloping manner such that the left half  104  entirely encases and contains the right half  106 . This action could be aided by pulling the right half  106  through the center point  116  and into the interior of the left half  104  as the left half  104  is being closed over the right half  106 . 
     The result of the folding and enveloping action described above is that what had been the outward facing surface of the left half  104  that holds the patches  112 ,  114  is now facing inward and in direct contact with the outward facing surface of the right half  106 . The patches  112 ,  114  also face inward and are completely contained within the layers of the now contiguous right half  106  and former left half  104 . Further, the circumference of the left end  108  now entirely encircles the circumference of the right end  110  at the toe portion of the double-layered sock. The two ends  108 ,  110  are stitched together which closes the toe area. At the other end, where the left welt  118  and the right welt  120  are now together at the opening of the double-layer sock, the two layers may be joined. 
       FIG.  2    provides a more detailed view of the components of  FIG.  1   . The tube  102 , which in  FIG.  2    is depicted as two socks joined at their welt areas, would not be shaped as socks during the manufacturing process described above until the double-layer sock is sewn. The double-layered structure would be placed on a form shaped as a sock to receive shaping and further treatment and be finalized as a finished product. 
       FIG.  2    depicts what are shown as the left half  104  and the right half  106  in  FIG.  1    as an outer layer and as an inner layer, respectively.  FIG.  2    also depicts components such as seam allowance, run guard, arch support, transfer, and blister guard/Achilles support that add value to the double layered sock but may not be directly relevant to systems and methods provided herein. Further, while the patches  112 ,  114  are described herein as silicone, they may alternatively or additionally be made of other substances that may comprise gel, polyurethane, and/or other polymers. 
       FIG.  3    depicts components and interactions of a system  300  of a double-layered sock. Components of the system  300  are indexed to the components of the system  100 .  FIG.  4    supports and supplements  FIG.  3    in the same manner as  FIG.  2    supports and supplements  FIG.  1   . 
     As noted, discussion of components and interactions of  FIG.  3    and the system  300  is supplemented by  FIG.  4   .  FIG.  3    depicts a second and different embodiment from the embodiment provided by  FIG.  1    and the system  100 . Whereas in  FIG.  1    the two halves  104 ,  106  are joined at a top or welt area and then closed together such that thereafter the toe area is to be sewn and closed, in  FIG.  3   , the two halves  304 ,  306  are joined at the toe and not at the top or welt as in  FIG.  1   . 
     In  FIG.  3   , the first patch  312  is proximate the center point  316  and the second patch  314  is about six inches to the left of the first patch  312 . This structure is in contrast with that shown in  FIG.  1    where the position of the patches  104 ,  106  is opposite that shown in  FIG.  3   . 
     When the left half  304  is folded over the right half  306  such that the right half  306  becomes enveloped into the left half  304  closing over the right half  306 , the toe area is at the center point  316  in contrast to what takes place in  FIG.  1   . The left end  308  in this second embodiment would encircle the right end  310  and together the left end  308  and right end  310  when sewn together would form the welt area of the double-layered sock. 
       FIG.  5    illustrates another embodiment wherein a second layer sole and toe cover may be added to a sock. The second layer would be pulled over the sock in a right to left manner as depicted in  FIG.  5   . The finished product is shown in a smaller image in the righthand area of  FIG.  5   .  FIG.  6    provides further detail regarding structure and placement of the patches. 
     Knitting Technique A is applicable to  FIG.  1   ,  FIG.  2   , and the system  100   
     Knitting begins at the toe of the sock and follows accordingly: 
     1. First a toe and run guard are knit allowing for seam allowance at the toe opening followed by continuous knitting into the ball area, further knitting into the arch area, the heel and ankle area and then to the top opening (in a way that are known techniques of knitting a sock). The machine then reverses the order of the knitting technique and does not cut or break at the first knitted portion but continues to a second sock or a continuous tube or cylinder comprising a first knit portion and a second knit portion. 
     2. The machine does not cut or drop the sock, it continues to knit the top opening, the ankle, the heel, the arch, the ball area, the toe area and run guard and seam allowance in order to create two socks connected at a fold line or a center point which divides the sock into two. 
     3. The sock is then steamed and shrunk for fit and allowed to dry or dried in a dryer if needed. 
     4. The extended sock or still-open-sock is then placed on a flat metal foot board or 3D foot insert where the gel, silicone, elastomer, or other polymer is added to the ball of the foot and heel in a specified pattern. 
     Knitting Technique B is applicable to  FIG.  3   ,  FIG.  4   , and the system  300 . 
     Knitting begins at the opening of the sock and follows accordingly: 
     1. First the sock opening and hem, transfer, or welt is knit. The ankle, then the heel, then the arch, then the ball, then the toe, then the run guard and toe seam allowance (as in the ordinary or known technique anyone trained in the art of sock knitting would understand). 
     2. The machine does not cut or drop the sock, it reverses the knitting sequence and continues to knit the toe seam allowance, toe run guard, toe area, ball area, arch area, heel area, ankle area, opening and a second transfer, hem, welt, or end of sock. 
     3. The sock is then steamed and shrunk for fit and allowed to dry or dried in a dryer if necessary. 
     4. The extended sock or still-open-sock is then placed on a flat metal foot board or 3D foot insert where the gel, silicone, elastomeric, or other polymer is added to the ball of the foot and heel. 
     In Knitting Technique B, the hem or top opening of the sock may be created by knitting a finished welt or transfer and finished on the machine. It may also be left unhemmed or welt free and hemmed at the final process after polymer application. As an alternative to the knit in welt hem, the first layer and second layer of the sock may be joined together at the opening of the sock with a cover stitch, overlock, double needle or flatlock stitch or other method of conventional sewing of stretch knits, socks, or footwear. 
     Knitting Technique C is applicable to  FIG.  5     
     1. First the sock opening, and hem, welt, or transfer is knit. The ankle, the heel, the arch, the ball, the toe, the run guard, and toe seam allowance. 
     2. The machine does not cut or drop the sock, it reverses the knitting sequence and continues to knit the toe seam allowance, toe run guard, toe area, ball area and top of sock past one to two inches from the end of toes where they join the foot. At this point, the top of the sock, just past the toe, ends the knitting and finishes before the instep (remaining top of sock). The lower portion continues to knit through the sole, all the way to the heel, but not up to the Achilles. 
     3. The sock is then steamed and shrunk for fit and allowed to dry or dried in a dryer. 
     4. The extended sock or still-open-sock is then placed on a flat metal foot board or 3D foot insert where the gel, silicone, elastomer, or other polymer is added to the ball of the foot and heel onto the first portion of the sock. 
     5. After the polymer is applied, the second partial portion is pulled back onto the sock and stitched into place covering the ball and heel. It is stitched in a manner that those skilled in the art of knitting or sewing would understand. 
     6. The toe seam is closed. 
     Knitting Technique D is applicable to  FIG.  6   . A polymer cushion may be incorporated as thread. 
     The polymer may be incorporated into the knit structure by splicing a polymer, elastomeric, or silicone-based thread or monofilament at the areas of desired cushion during the knitting process. The material could be silicone, polymer, elastomeric polymer, gel, or polyurethane. 
     As the machine knits portion or sock at the ball or heel of the foot, whichever comes first, the knitting machine will be programmed to splice in a polymer yarn (as described above) such that added cushion is applied but cover yarns are used to encase the thread or yarn inside of the traditional cover yarns like nylon, polyester, or cotton or other known natural or synthetic yarns. 
     1. The sock is knit single layer beginning at the top opening of the sock or toe. If the toe, the knitting technique will be reversed, but the splicing technique or splicing areas would remain the same. 
     2. The hem, welt, or top opening finish is knit followed by any leg portion of the sock and the ankle. 
     3. After the ankle, at the heel, a covered, elastomeric yarn is spliced in to create padded loops as in a terry cloth or piled knit structure. The elastomeric yarn acts as a cushion. 
     4. The elastomeric polymer can be covered with any commercial yarn, synthetic or cotton such as nylon, polyester, cotton, rayon, cellulosic fiber, or other known yarn used in sock making. 
     5. The covered elastomeric polymer is spliced in at the heel. 
     6. After the spliced polymer is added the sock continues to knit the instep and sole. 
     7. At the sole and instep where the arch is, a specified denier is added which is heavier than what is in the base layer of the sock to provide arch support. 
     8. After the arch support, the ball area is knit by splicing in the covered elastomeric polymer in the specified area. 
     9. The toe area is knit without the covered polymer. 
     10. The toe is closed. 
     11. The sock is steamed and dried. 
     12. The sock is boarded. 
     The polymer is applied in one of four ways. 
     Application method #1 
     The polymer is applied as a viscous, spreadable gel formula as a screen print. 
     1. The sock is pulled onto a metal flat form or 3D form. 
     2. A metal plate with cut-outs of the shape of the desired end result shape and thickness is placed over the sock. 
     3. An arm or spatula spreads the polymer over the metal plate which is above the sock. 
     4. The sock is then coated with the polymer in the shape desired. 
     5. If multiple thicknesses of the polymer are desired, the polymer may be coated onto the sock in a series until the desired thickness is achieved. 
     6. If multiple patterns are required, there may be the need for multiple metal plates and a curing time between each one. 
     Application method #2 
     The polymer may be applied in a solid form by adhering the polymer shape directly onto the sock. 
     1. The sock is pulled onto a metal flat form or 3D form. 
     2. A premade and cured polymer shape or sheet is placed onto the ball or heel or specified area of the foot and pressed and/or heat set into place. 
     Application method #3 
     The polymer may be applied through hot melt method. 
     1. The sock is pulled onto a metal flat form or 3D form. 
     2. A mechanical strainer is used to press the viscous polymer directly onto the sock in the desired shape and thickness. 
     3. The sock is then coated with the polymer in the shape desired. 
     4. If multiple thicknesses of the polymer are desired, the polymer may be coated or hot melted or applied onto the sock in a series until the desired thickness is achieved. 
     5. If multiple patterns are required, there may be the need for multiple pattern strains and a curing time between each one. 
     In the above application methods 1, 2, and 3, once the polymer application is cured and set, the sock is then closed by pulling the second portion of the sock onto the first portion of the sock. This encapsulates the polymer in between two layers. 
     Polymer as thread, yarn, or fiber: 
     1. An elastomeric polymer in the form of thread, fiber or yarn is threaded onto the knitting machine. 
     2. It will be covered, braided, plied, wrapped, or placed with other commercial synthetic or natural yarns. 
     3. The elastomeric polymer thread will be spliced into the sock at the heel or ball or as specified by the sock design. 
     The sock is then closed at the toe seam and is closed at the top opening, if necessary; and if needed, a stabilizing stitch is sewn at the top opening to avoid slippage for application methods 1 and 2. 
     Knitting Structure (Yarn combination in another section) for application methods 1 and 2: 
     The first knit portion may contain a yarn combination inclusive of all needle heads or feeds of which some will drop out or less feeds will be included in the second sock portion. 
     The first sock portion or the portion which will be visible to the wearer when on body: 
     The toe portion will be a jersey knit structure containing a yarn combination of elastane, synthetic, and or natural fibers and any composition of those thereof. The toe portion contains the following sections: 
     Seam allowance for stitching toe seam Run guard for protection from toenails, stitching of toe seam and general wear at toe seam. 
     Sock body beginning: 
     The run guard and seam will be a jersey knit with wales and courses of a specified range but could also be an alternative knit structure. 
     The sole at ball and heel will be jersey knit (or other known knitting structure) with wales and courses of a specified range and can utilize the full needle head or feeds. 
     The arch of foot will splice in a spandex denier stronger or higher than in the body of the sock or utilize a tighter knitting structure for arch support. The spandex range at the arch may be a range of 20 denier to 210 denier and a specified range of wales and courses. 
     Front and back of sock (if sock covers the lower leg) will be jersey knit or any other known or suitable knit structure and cuff may be ribbed or any other known or suitable knit. The top of instep will be a pique, jersey, or other knit stitch and cover the top of the foot. 
     The second knit portion will be knit with a lighter weight or finer yarn or yarn combination in comparison to the first portion for the sock not to be thicker when doubled than a traditional sock worn by consumers for running, walking, or wearing shoes. 
     The run guard and seam may be a jersey knit (or other known knit structure) with a specified range of wales and courses. 
     The sole at ball and heel will be jersey knit (or other known knit structure) with a specified number of wales and courses and can utilize the full needle head or feeds. 
     The arch of foot will splice in a spandex denier higher than that used in the first portion of the sock or tighter knitting structure for arch support. 
     Front and back of sock (if sock covers the lower leg) will be jersey knit and cuff may be ribbed. The top of instep will be a pique, jersey, or other knit stitch and cover the top of the foot. 
     The sock may be knit with any knit structure regularly used by anyone knowledgeable in the art of sock knit structures in various combinations of areas, yarn combinations, and knit structures and can vary by area of the sock. 
     Polymer Structure: 
     The polymer structure is comprised of an elastomeric material formed into a specific geometric pattern. This custom geometric pattern is designed in such a way to fit naturally to the shape of the sock and be easily compatible with the polymer application methods listed above. 
     The design of this geometric pattern is such that the resulting grid pattern allows for adequate air and moisture transfer while providing localized support in key pressure point areas. The thickness of this polymer structure is either a varying thickness or an even thickness, with then intent to further accommodate the key pressure point areas. 
     The specific material or material compound used to create this polymer structure will have the following material properties:
         Hardness: (Shore 00-0) to (Shore A-40)   Compressive Strength: 5 MPa to 35 MPa   Water Absorption: No greater than 3.00%   Density: No greater than 4.50 g/cc   Linear Shrinkage: No greater than 0.35 mm/mm   Modulus of rigidity (20° C.): No greater than 1.00 MPa       

     These material properties may be achieved by utilizing materials including, but not limited to, the following:
         Ethylene Propylene Diene Monomer (EDPM)   Natural Rubber (NR)   Silicon Rubber   Neoprene Polymer   Urethane Rubber   Polyurethan Rubber       

     The geometric pattern can be scaled as needed to accommodate the specific application method used. Following the polymer application, the resulting polymer structure should match the pattern design shown below, with a maximum allowable deviation tolerance of 2.00%. 
     Once the polymer application has been completed, the resulting polymer structure provides a targeted stress distribution, minimizing specific pressure points and providing a padded cushion while effectively and evenly spreading the pressure outward across the structure. 
     The maximum thickness of this polymer structure is not to exceed 2.00 mm. This ensures the end product maintains flexibility and aesthetic characteristics consistent with a standard sock and is not adversely impacted by machine washing or extended wear. 
     Cushion Technology:
         A. Applied as molded solid structure   B. Applied as printed viscous gel or liquid   C. Applied as thread, fiber, or yarn   Polymer cushion incorporated as thread.       

     The polymer may be incorporated into the knit structure by splicing a polymer, elastomeric, or silicone-based thread or monofilament at the areas of desired cushion during the knitting process. 
     As the machine knits portion or sock at the ball or heel of the foot, whichever comes first, the knitting machine will be programmed to splice in a polymer yarn such that added cushion is applied but cover yarns are used to encase the thread or yarn inside of the traditional cover yarns like nylon, polyester, or cotton or other known yarns. 
     Yarn Combination: 
     The first and second half of the sock is made of a combination of synthetic and natural yarn twisted, braided, bundled, or covered with spandex or elastane. The sock may be combinations of the following:
         Nylon, polyester, cotton, spandex   Nylon, rayon, polyester, spandex   Bamboo, rayon, polyester, spandex   Nylon, cotton, spandex   Polyester, cotton, spandex   Cotton and spandex   Covered spandex   Bare spandex   Commercial blends of all natural, all synthetic, or a combination of synthetic and natural fibers including cellulosic fibers.       

       FIG.  7   ,  FIG.  8   , and  FIG.  9    are illustrations of the polymer pad.  FIG.  9    depicts portions of the pad including small and large grid sections and load transfer structure of a typical pad. 
     While a substantial portion of the discussion herein describes a structure in which the polymer pad is knit in a continuous tube or cylinder, that in embodiments may be about 24 inches in length prior to the drawing action, the structure provided herein may also be characterized as the polymer pad being knit such that there may be two layers to encapsulate the pad. In embodiments, the processes described at length above regarding one half of the single tube being folded over and enveloping the other half of the tube with the polymer pads sandwiched within may not be used. In some alternative embodiments, the single tube may not be used, and the process may instead begin with two separate tubes of equal or non-equal size. The polymer pads may be attached to one of the tubes using the methods described herein. The tube with the polymer pads may then be made to cover over the other tube using various methods or be placed inside of the other tube using other various methods. The two separate tubes may then be joined via stitching or other known method. 
     In an embodiment, a method of creating a cushioned sock whereby a polymer cushion is positioned between an outer and an inner layer of yarn or fabric is provided. The method comprises horizontally positioning a first and a second layer of fabric, the first layer atop the second layer. The method also comprises attaching a first polymer cushion to the first layer tube about two inches from a left end. The method also comprises attaching a second polymer cushion to the first layer about five inches from the first polymer cushion and toward a center area of the layers. The method also comprises drawing a left half of the layers completely over the right half of the layers, the drawing action causing a full exterior surface of the left half to become an interior surface covering an exterior surface of a right half. A cushioned sock is created whereby the polymer cushions are positioned between an outer and an inner layer of yarn or fabric. A sewing action closes the left half atop the right half. An opening at an end opposite a toe area comprises a welt area is not sewn and promotes insertion of a foot of a user. The first polymer cushion is positioned at a ball area of the foot and the second polymer cushion is positioned at a heel area of the foot. The drawing action results in the polymer cushions to be sandwiched between the layers. The polymer cushions are made from at least one of silicone, gel, polyurethane, and at least one additional polymer. The first layer and the second layer are about twenty-four inches in length. Based on the drawing action, the first polymer cushion and the second polymer cushion are encased between the layers.