Abstract:
A personal flotation device is described which is in the form of a flexible garment or combination of garments made from liquid impervious filaments of buoyant material. The garment or combination of garments accommodate movement of the wearer while providing the wearer with buoyancy.

Description:
FIELD 
       [0001]    There is described a personal flotation device that has a different construction and takes a different form from traditional personal flotation devices. 
       BACKGROUND 
       [0002]    Personal flotation devices, or “PFDs”, have evolved over the years from the old “Mae West”, or kapok, type of life vests; then, to vinyl covered foam rubber life jackets; and, finally, to more specialized flotation devices which are used when one engages in different types of water sports and boating activities, these more modern PFD&#39;s are typically fabric covered flotation foam panels sewn into vests, jackets or even full body suits. Recently inflation style PFD&#39;s have also become popular. Typically formed into a vest or belt, they can be activated manually or by immersion in water. Compressed air from a high pressure bottle is released into an air holding flotation bladder that is incorporated into a vest or belt. 
         [0003]    The U.S. Coast Guard has instituted regulations regarding the minimum flotation required of PFDs. As set forth in those regulations, the minimum flotation required depends upon the expected use of the PFD. The U.S. Coast Guard Regulations, Title 33 of the Code of 
         [0004]    Federal Regulations (“CFR”), Chapter 1, Part 175, Subpart B, require that recreational boats have at least one Coast Guard approved PFD on board for each person on a boat. 
         [0005]    In the past, increasing the buoyancy of PFDs has generally required that there be an associated increase in the bulk of the PFD, as additional buoyant material is required to increase a PFD&#39;s buoyancy. The addition of thicker and/or additional buoyant material to a PFD typically results in increased bulk which tends to inhibit or restrict the freedom of movement of the wearer. This restriction on the freedom of movement of the wearer is especially a problem for PFD wearers who are involved in strenuous water sport activities which require a significant amount of movement of their arms, shoulders, and torso. By way of example, in kite boarding, stand up paddle boarding, canoeing, kayaking, rafting, sailing, wind surfing, or similar activities, significant arm, shoulder, and upper torso movement is required when the wearer is paddling or manoeuvring control bars, sails and lines. In addition, most conventional PFDs do not tend to move with the wearer. Instead, they tend to ride up, or shift, on the wearer&#39;s torso, thereby making the PFD uncomfortable to wear and also interfering with the wearer&#39;s mobility. Current PFD solution also restricts the flow of air over the user, which can cause discomfort and overheating in hot conditions. Alternatively, the outer fabric coverings on current life jackets hold water which can cause a cooling effect perhaps desirable in the heat, however this evaporation cooling can add to the chance of hypothermia in cold conditions. 
         [0006]    Unfortunately, many persons are preferring to assume a risk of drowning rather that wear an uncomfortable and activity restricting PFD. In recent years, concerns regarding non-compliance have caused the U.S. Coast Guard to modify the Regulations regarding minimum flotation for PFDs. Accordingly; PFDs are now segregated into different classes which depend upon the type of boating activity in which the PFD is intended to be used. Generally, there are five classes of PFDs as stipulated within the U.S. Coast Guard Regulations. They are designated as Type 1, offshore life jacket; Type 2, near shore buoyant vest; Type 3, flotation aid; Type 4, throwable device; and Type 5, special use device. The Type 3 PFDs, or flotation aids, are generally the best suited for most recreational water sports in which a significant degree of mobility, and arm and shoulder movement, are involved. Accordingly, they tend to be the most common type of PFDs in use. The U.S. Coast Guard Regulations require that all Type 3 PFDs have a minimum of 15.5 pounds of flotation when they are manufactured. As most adults generally weigh between 10 and 12 pounds when submerged in water, i.e., significantly less than the minimum Coast Guard flotation requirement, the provision of at least 15.5 pounds of buoyancy is sufficient to help insure that a person wearing such a PFD, properly fitted, will be able to float. 
         [0007]    PFDs are generally constructed of a fabric material which encloses or is laminated to a panel of foam material which is used for flotation. Typically, the fabric material is sewn around the foam material thereby enclosing and protecting the flotation foam in a fabric “pocket”. As is well known in the art, the present design of PFDs includes a number of sewn pockets, each of which typically retains a cut slab of flotation foam. The size and shape of the pockets, and the size and shape of the enclosed foam, must, of course correspond to one another. As the foam which is typically used in a PFD is firmer than the surrounding fabric material, bending of the PFD can be enhanced by providing a seam between adjacent foam-holding pockets. This is commonly referred to as a “quilting seam”. As is well known to those skilled in the art, present and past PFDs of this type exhibit substantial amounts of sewing, and numerous seams, in order to provide its desired shape, while enclosing a sufficient quantity of flotation foam to provide at least the minimum flotation required by the U.S. Coast Guard regulations for the type of PFD being manufactured. In addition, the sewn seams allow for increased bending of the PFD where desired. Even a relatively simple PFD design will generally include at least two side panels, a back panel, and, typically, at least two front panels (which are usually joined together by some sort of closure system, such as straps or a zipper, when the PFD is worn). Thus, even a simple design for a PFD may include five pockets, each of which encloses a piece of flotation foam which has been cut to the desired shape prior to being inserted into the pocket which is formed in the fabric material to receive the flotation foam. If more complicated designs are desired, for example, to provide for more conformal bending of the PFD, then it is necessary to include additional seams where such additional bending is desired, as the seams act as the “hinges” between adjacent panels. As quilting seams are added, there is the obvious loss of space within the empty fabric envelope, which translates into less space available for the flotation material itself, and, therefore, reduced flotation and buoyancy of the PFD. Of course, using current manufacturing techniques and materials, this means that there must be additional pieces of foam, and/or pieces of additional thickness, as well as additional sewn seams, all adding to the complexity of the design, the number of seams required, and the labour and material costs associated with manufacturing the PFD. A more recent innovation is molding the flotation foam in three dimensional shapes that streamlines the fit of PFD&#39;s for action water sports. These formed flotation panels are often laminated with a secondary fabric or film layer during the molding/embossing process. 
         [0008]    While those skilled in the art will recognize that “belts”, vests, rafts, and some other flotation articles have been made for some time by dipping a flexible flotation foam panels into a liquid vinyl, so that the vinyl forms a skin over the foam, the use of such technology has generally been limited to providing flotation devices (belts and vests) for use by water skiers. Typically, devices manufactured using the vinyl dipping technology of the prior art are notoriously hot, and they stick to the skin. Further, they typically tend to crack around the edges, so they were not only uncomfortable, but they cause abrasion, particularly around the armholes and sides. 
         [0009]    Adding to the foregoing problem is that the U.S. Coast Guard Regulations require that the flotation in a PFD be provided by an approved material, and the only presently approved flotation materials are flotation foams. The U.S. Coast Guard has approved the use of Neoprene as a fabric in manufacturing PFDs. Neoprene is a soft, elastic, stretchable, flexible polychloroprene foam material, which can be laminated to a segmented polyurethane known as LYCRA (a synthetic fiber produced by E. I. DuPont de Nemours and Company, located in Wilmington, Del.). While Neoprene, laminated with Lycra, is an approved fabric, neither Neoprene nor Neoprene laminated with LYCRA can be used alone to replace flotation foam. Instead, the laminate is used to enclose an approved foam in a PFD. Other stretch fabrics, such as a spandex omni-directional wrap knit laminated to a monolithic film which is known as DARLEXX (an elastic fabric produced by Darlington Fabrics Corporation, New York, N.Y.), are not approved for use to enclose approved flotation foams in PFDs. 
       SUMMARY 
       [0010]    It is an underlying premise that PFDs would be more likely to be worn if they had the same fit and comfort as standard clothing and became a preferred garment when in the general marine environment. Such an innovation would lower the mortality rate due to drowning, as the PFD would double as a comfortable garment on or off the water. A need has existed for a PFD which flexes with, and conforms more naturally to, ami, shoulder, and torso movement of a wearer, so that as the wearer moves, the PFD moves with the wearer. A PFD which moves with the wearer, rather than shifting, is far less likely to become uncomfortable for the wearer or to interfere with, or restrict, the movements of the wearer. 
         [0011]    Accordingly, there is provided a personal flotation device which is in the form of a flexible garment or combination of garments made from filaments of liquid impervious buoyant material. The garment or combination of garments accommodate movement of the wearer while providing the wearer with buoyancy. 
         [0012]    While there may be various materials that are suitable, beneficial results may be obtained through the use of a closed cell foam. Closed cell foam is known as a liquid impervious buoyant material. It can also be extruded to form filaments of any desired length and any desired cross-sectional shape. 
         [0013]    With the approach described above, there are any number of garments that can be made to provide the desired buoyancy. Those garments may include: a jacket, sweater, a vest, a pair of pants, a full body suit, gloves, mitts, socks, belts, arm sleeves, leggings, hats and belts. It must be emphasized that if the new personal flotation device is to be worn as clothing, the desired buoyancy may be achieved through an ensemble of garments. For example, government mandated buoyancy standards may be met or exceeded by a combination that includes a sweater, a pair of pants and a vest. 
         [0014]    The properties of the garments will be varied depending upon the environment in which they are intended to be worn. For example, when active in frigid waters, the garments may be tightly woven or knitted with a view to provide thermal insulation properties and the combination may include gloves, socks, and a hat to reduce loss of body heat. In contrast, when active in a warm climate, the garments may be loosely woven to allow for cooling ventilation for the comfort of the wearer. 
         [0015]    While the thickness of the closed call foam must be sufficient to provide the necessary buoyancy, it should not be so thick as to restrict movement. The objective is to have the PFD become an article of clothing. It is preferred that the thickness vary between 2 mm and 6 mm. Around the torso, the thickness can be 4 mm to 6 mm. However, around the arms and legs, the thickness may be 2 mm to 3 mm, so as to provide the desired freedom of movement. By controlling the density of the closed cell foam, one is able to increase or decrease the buoyancy with these thickness dimensions in mind. 
         [0016]    Once the basic principle is understood there are various enhancements which may be added to enhance the durability, construction and appearance of the garments. Those variations will hereinafter be further described. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    These and other features will become more apparent from the following description in which reference is made to the appended drawings, the drawings are for the purpose of illustration only and are not intended to be in any way limiting, wherein: 
           [0018]      FIG. 1  is a perspective view of a prior art PFD; 
           [0019]      FIG. 2  is a plan view showing a PFD made from one embodiment of the invention; 
           [0020]      FIG. 3  is a perspective view of a foam flotation filament; 
           [0021]      FIG. 4  is a perspective view of a foam flotation filament with an external sheath; 
           [0022]      FIG. 5  is a sectional view of a segmented flotation filament encapsulated with an external sheath; 
           [0023]      FIG. 6  is a perspective view of a flotation filament with an internal fiber yarn or monofilament line; 
           [0024]      FIG. 7  is a perspective view of a flotation filament wrapped with a fiber yarn or monofilament line; 
           [0025]      FIG. 8  is a perspective view of sealed polymer tubing flotation filament; 
           [0026]      FIG. 9  is a plan view of a woven flotation filament textile; 
           [0027]      FIG. 10  is a plan view of a knitted flotation filament textile; 
           [0028]      FIG. 11  is a plan view of an embroidered flotation filament textile; 
           [0029]      FIG. 12  is a plan view of a chain link flotation filament textile; 
           [0030]      FIG. 13  is a perspective view of an interlocking flotation filament textile; 
           [0031]      FIG. 14  is a perspective view of an intersecting flotation filament textile; 
           [0032]      FIG. 15  is a plan view of a composite woven flotation filament and yarn textile; 
           [0033]      FIG. 16  is a plan view of multiple flotation filaments wound together to make a flotation yarn; 
           [0034]      FIG. 17  is a plan view of multiple flotation filaments braided together to make a flotation yarn; 
           [0035]      FIG. 18  is a plan view of woven flotation filament textile pieces welded together; 
           [0036]      FIG. 19  is a plan view of woven flotation filament textile pieces glued together; 
           [0037]      FIG. 20  is a plan view of woven flotation filament textile pieces sewn together; 
           [0038]      FIG. 21  is a perspective view of panels of a PFD made from woven flotation filament textile; 
           [0039]      FIG. 22  is a perspective view of panels of a PFD, made from woven flotation filament textile, joined together; 
           [0040]      FIG. 23  is a sectional view of woven flotation filament textile laminated on both sides with a woven fabric or film to create a multi-layer composite material; 
           [0041]      FIG. 24  is a sectional view of a woven fabric or film laminated on both sides with a woven flotation filament textile; 
           [0042]      FIG. 25  is a plan view of a flotation garment made from woven flotation filament textile and synthetic fabric; 
           [0043]      FIG. 26  is a sectional view of woven flotation filament textile inserted into textile pocket; 
           [0044]      FIG. 27  is a plan view showing sheared woven flotation filament textile; 
           [0045]      FIG. 28  is a plan view showing stretched woven flotation filament textile; 
           [0046]      FIG. 29  is a sectional view showing a flotation filament textile with a hard shell; 
           [0047]      FIG. 30  is a plan view of a flotation garment made from a knitted flotation filament textile. 
       
    
    
     DETAILED DESCRIPTION 
       [0048]    A personal flotation device, and the manner of making the same, will now be described with reference to  FIG. 1  through  FIG. 30 . 
         [0049]    Structure and Relationship of Parts: 
         [0050]    The process of extruding, molding, slicing, shaping closed cell foams such as PE, EPE, EVA, Neoprene, Silicone and NBR has allowed for the creation of very light floating (buoyant) filaments to be manufactured in a wide variety of diameters, densities, profiles and shapes . Depending on the density of the foam, the flotation filament in its pure from can be woven into a fabric, which is then cut into pattern pieces for assembly into a form fitting garment. The cut edges of the pattern pieces can be attached to one another by sewing, welding, gluing or other connection methods to seal the foam filaments and connect the pattern pieces. By using a knitting, process the flotation filaments can also be woven directly into formed shapes using a process similar to knitting sweaters. Tubular shapes, garments and shaped covers can be manufactured. 
         [0051]    With lower density flotation filaments it may be desirable to cover or sheath the flotation filaments with fabrics coverings such as Lycra. By covering a flotation filament with a Lycra sleeve, it is possible to meet the US Coast Guard Type 3 material certification allowing the creation of certified flotation garment providing the minimum flotation of 15.5 pounds is achieved. Adding the Lycra covering to the flotation filament would also increase the durability and abrasion resistance while improving the stretch characteristics of the flotation filament. Flotation filaments can also be sheathed or covered with modern technical fabrics such as Kevlar for or Nomex for their specific properties in strength and fire resistance, however this may negate US Coast Guard Approval. Flotation filaments can also be supported by single yarns of woven fibres such as carbon or spectra if stretch is not desired in the flotation filament. 
         [0052]    Flotation filaments can be woven in various configurations and tensions to create varying gaps or spaces between the flotation filaments weave. Tighter weaves offer less breathability while increasing protection from elements such as wind, rain, and immersion in water. Looser or more open weaves of the flotation filaments will allow more air transfer between the filaments providing additional breathability, ideal for warmer conditions. A more open weave of the flotation filaments would also be desirable if flotation weave panels are sandwiched between or attached to woven fabric or film layer. An example of this would be replacing solid foam panel as used in traditional life jackets with a flotation weave panel. 
         [0053]    The correct combination of density and durability in the flotation filaments will allow a one piece garment, jacket, pants, hat or other bodily worn accessories to be woven with the flotation filaments. A garment woven with flotation filaments can be worn as insulated clothing as the filaments provide comfort, stretch, insulation and breathability to the user, similar to wearing a garment made with natural or synthetic fibres spun or twisted into a yarn. In the marine environment a garment woven partially or in its entirety with flotation filaments will transform the garment into a comfortable personal flotation device or PFD. An example of this would be a jacket with the torso that is woven with flotation filaments while the arms are constructed with a fabric consisting of yarns spun with synthetic fibres. Panels or inserts of woven flotation filaments could also be used to enhance the performance of traditional style PFD&#39;s or flotation garments by replacing the non-breathing, low stretch solid sheet flotation foam. The woven flotation filaments can be suspended within a sandwich of overlaying fabrics that provide abrasion, weather protection and enhanced stability to the flotation filament weave. 
         [0054]    Flotation filaments woven into a panel or sheet can also be laminated to backing fabrics by use of adhesives to polymer membranes such as Teflon, PU, PPE. Laminated to such membranes, the textile would be locked into place and made waterproof and breathable. Flotation filaments woven into a textile can also be laminated by use of adhesive films or heat to other woven fibre textiles such as Nylon, Kevlar, and Lycra providing additional stability, abrasion and weather resistance to flotation filament textile. 
         [0055]    The flotation filament textile can also be laminated into a composite material similar to neoprene sheet goods for use in the manufacture of items like wetsuits and dry-suits. With the flotation filament textile providing flotation, insulation and stretch, additionally laminated fabrics or films would provide additional heat retention, abrasion resistance, support and UV protection to flotation filament textile from the marine environment. 
         [0056]    The flotation filaments can be formed into textiles sheets or rolls by traditional weaving techniques as used with fibre spun yarns when they are woven into textiles. The flotation filaments can also be connected by interlocking profile shapes that allow the flotation filaments to be interlocked by the nesting, profile of the flotation filament. 
         [0057]    The flotation filaments can be further connected by intersecting filaments or yarns via pass through slots or holes molded or cut into the flotation filaments. Individual flotation filaments can be twisted together to create flotation yarns, which in turn can be woven into a flotation fabric. The flotation filaments can also be formed into flotation filament links. These links which can be closed or open in shape are then connected by interlocking, or by other means such as glue, welding, clips, yarns or monofilaments to create a textile. The resulting fabric of this style of assembly would be similar to chain mail. The links can be circular, square, or of any shape and profile. The links can be a closed or open shape as long as they interconnect together and creates a textile that be used for a PFD&#39;s, garment or other non-apparel applications. Weaves of flotation filament can be also be embossed via pressure, heat and adhesives to fuse the filaments or modify the profile and density of the flotation filament textile. 
         [0058]    The buoyant flotation filaments described above enable the manufacture of PFDs using U.S. Coast Guard approved flotation materials that does not upon rely the standard methods of construction using foam panels, laminated, quilted or in pure non-laminated state, cut into flat pattern pieces using that use shaping seams and stretch panels or gussets to form vests, jackets, pants or full body suits. The buoyant flotation filaments form a garment to allow high comfort and breathability to user as found with non-flotation garments such as knitted sweaters or woven garments used outside the PFD market. Use of the buoyant filaments results in a garment for the marine environment, that is as comfortable to wear as standard clothing, to be used for both insulation and flotation as it could worn at all times, and used under productive shielding garments such a rain pants, jackets, wetsuits or dry-suits. It is feasible that a mixture of closed cell flotation filaments and other filaments could be used on the same garment or covering to offer flotation, insulation and cooling. 
         [0059]    It will be appreciated by a person skilled in the art that the garment that serves as a PFD, could be made for an animal, such as the family dog. In such case, the “wearer” would be the dog. It will also be appreciated that the flotation filaments can be treated with anti-microbial, anti-fungal and other agents. It will further be appreciated that, as long as the necessary buoyancy is maintained, the flotation filaments may be combined with other filaments. It will be appreciated that the flotation filaments have other properties that make them desirable in marine applications. For example, the flotation filaments provide padding. If padding is desirable in a particular application, the size of the flotation filaments can be increased to intentionally enhance the padding feature. 
       LEGEND OF REFERENCE NUMERALS 
       [0060]      1 —Flotation filament 
         [0061]      2 —Flotation filament Link 
         [0062]      3 —Interlocking Flotation filament 
         [0063]      4 —Slot in Flotation filament 
         [0064]      5 —Fiber Yarn or Monofilament Strand 
         [0065]      6 —Panel made from Woven Flotation Filaments 
         [0066]      7 —Personal Flotation Device Made From Woven Flotation filament Textile 
         [0067]      8 —Welded Connection 
         [0068]      9 —Glued Connection 
         [0069]      10 —Fabric Strip 
         [0070]      11 —Sheath 
         [0071]      12 —Fiber Yarn or Monofilament Strand 
         [0072]      13 —Polymer Tubing 
         [0073]      14 —Plug 
         [0074]      15 —Mesh Fabric 
         [0075]      16 —Woven fabric or Film 
         [0076]      17 —Sewing 
         [0077]      18 —Gap or Space Between Flotation filament Weave 
         [0078]      19 —Interlocking Connection 
         [0079]      20 —Zipper 
         [0080]      21 —Flotation Garment Made From Woven Flotation filament Textile and Synthetic Fabric 
         [0081]      22 —Sleeves Made From Synthetic Fabric 
         [0082]      23 —Woven Flotation filament Textile 
         [0083]      24 —Textile Pocket 
         [0084]      25 —Pulling Force 
         [0085]      26 —Protective Hard Shell 
         [0086]      27 —Knitted Flotation filament Textile 
         [0087]      28 —Flotation Garment Made From Knitted Flotation filament Textile 
         [0088]    In this patent document, the word “comprising” is used in its non-limiting sense to mean that items following the word are included, but items not specifically mentioned are not excluded. A reference to an element by the indefinite article “a” does not exclude the possibility that more than one of the element is present, unless the context clearly requires that there be one and only one of the elements. 
         [0089]    The scope of the claims should not be limited by the illustrated embodiments set forth as examples, but should be given the broadest interpretation consistent with a purposive construction of the claims in view of the description as a whole.