Abstract:
A helmet liner that is infinitely adjustable by the user in the field is provided. The helmet liner includes front, center and rear cushioning portions with integrally formed spaces between the front and center portions, and the rear and center portions. The integrally formed spaces provide the liner with the ability to independently flex [in one degree of freedom] and bend [in a second degree of freedom] to collapse the spaces without any overlapping of cushioning portions and thereby conform the liner to the hemi-spherical shape of the wearer&#39;s head. The spaces provide ventilation for the wearer&#39;s head. The helmet liner may also provide for variable thickness of one or more of cushioning portions as well as antimicrobial treatment of the fabric. By increasing the thickness of the rear cushioning portion with respect to the front cushioning portion, the number of optimum fits achieved by the liner is maximized, while biasing the wearers head toward the front of the helmet, thereby increasing the wearer&#39;s field of view (FOV).

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to helmet liners. More particularly, it relates to a removable safety and comfort liner having an infinitely adjustable configuration. 
     2. Description of the Prior Art 
     Various forms of pad sets for protective helmets are known in the prior art. These pad sets are designed to provide comfort while maintaining helmet shell stability and adding supplemental impact protection at a given compression. In order to meet these various requirements, helmets may be “fitted” by selecting pads for a particular individual or size range. To equip helmets with a pad set, a variety of different types of pads must be maintained in inventory. Due to the relatively small size of the individual pads, they can be easily lost in the field. 
     Other approaches provide a single piece helmet liner. Some examples may be seen in U.S. Pat. Nos. 5,687,426 and 5,946,734 and 6,453,476. To achieve a high level of comfort, some single piece liners are individually fitted to a wearer&#39;s head. U.S. Pat. No. 4,432,099 discloses a liner made from layers of thermoplastics sheets that are heated to deform during a fitting procedure. 
     It would be desirable to provide a single piece helmet safety liner that is simply fitted by the wearer without requiring tools or assistance and provides flexibility for further adjustment at any time. 
     SUMMARY OF THE INVENTION 
     It is therefore an aspect of the invention to provide a safety helmet liner that is user adjustable in the field for comfort. 
     It is a further object of the present invention to provide a ventilated one-piece liner that is treated with antimicrobial agents. 
     It is another object of the present invention to provide a liner with selectable, paired foam layers. 
     These and other related objects according to the invention are provided in a safety helmet liner that includes an upper helmet engaging side and a lower head engaging side. A pair of oval shaped cutouts define a front forehead cushioning strip. A pair of J-shaped cutouts define a rear nape cushioning strip. A centrally positioned crown cushioning strip is formed between the oval shaped cutouts and the J-shaped cutouts. Two pairs of straps are connected to opposing ends of the forehead cushioning strip and the rear cushioning strip, wherein the straps are releasably connected to ends of said crown cushioning strip. Alternatively, one pair of straps are connected to the crown cushioning strip and are releasably connected to the ends of the forehead cushioning strip and the rear cushioning strip. 
     The rear cushioning strip is C-shaped and has ends that interlock with said J-shaped cutouts. The lower head engaging side of the liner includes an anti-microbial fiber, element, treatment or agent for preventing growth of bacteria and fungus in the helmet and the helmet liner. The upper helmet engaging side of the liner further comprises a textured loop surface for use in a hook and loop fastening arrangement. The straps include a hook like structure for adjustably adhering the same to said textured loop surface. During fitting, the straps are adjustably positioned on the ends of the crown cushioning strip. The adjustable positioning of the straps enables infinite adjustability of the liner on a wearer&#39;s head. Alternately, during fitting the straps are adjustably positioned on said ends of the forehead cushioning and rear cushioning strips. The adjustable positioning of the straps enabling infinite adjustability of the liner on a wearer&#39;s head. 
     Within the fabric casing, the liner contains a visco-elastic foam layer and a supportive foam layer bonded to said visco-elastic layer. The visco-elastic foam layer is disposed on the lower head engaging side of the liner. The thickness of the foam layers may be modified to provide at least one of the cushioning strips with a thickness greater than the other of said cushioning strips. To improve the helmets FOV, or shift the center of gravity back, the rear cushioning strip is thicker than the forehead cushioning strip. The rear strip may also be thicker than the crown strip. Moving the center of gravity rearward, may be desirable if heavy equipment, like night vision goggles, are installed on the front of the helmet. 
     Alternatively, we describe our helmet liner as having a fabric outer casing and a forehead cushioning strip. A crown cushioning strip is hingedly connected to the forehead cushioning strip. A rear cushioning strip is hingedly connected to the crown cushioning strip. A set of straps is connected to one of the cushioning strips. The straps releasably connect the forehead cushioning strip and the rear cushioning strip to the ends of the crown cushioning strip. 
     The straps enable the forehead cushioning strip and the rear cushioning strip to encircle a wearer&#39;s forehead and the rear of their head at adjustable circumferences and adjust the liner according to the size of the wearer&#39;s head. A first pair of integrally formed spaces resides between the forehead cushioning strip and the crown cushioning strip. A second pair of integrally formed spaces resides between the crown cushioning strip and the rear cushioning strip. The first pair of integrally formed spaces comprise opposing oval cutouts disposed between the forehead cushioning strip and the crown cushioning strip. The second pair of integrally formed spaces comprise opposing J-shaped cutouts disposed between the crown cushioning strip and the rear cushioning strip. 
     The lower head engaging side of the liner includes an anti-microbial fiber, element, treatment or agent for preventing growth of bacteria and fungus in the helmet and the helmet liner. Within the outer fabric casing, the liner includes a visco-elastic foam layer and a supportive foam layer bonded to said visco-elastic layer. The visco-elastic layer is disposed on the lower head engaging side of the liner. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other aspects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein. 
       In the drawings wherein like reference numerals denote similar components throughout the views: 
         FIG. 1  is top view of the helmet liner according to an aspect of the invention; 
         FIG. 2A  is a bottom view of the helmet liner according to an aspect of the invention; 
         FIG. 2B  is a bottom view of the helmet liner according to another aspect of the invention; 
         FIG. 3  is a top view of the helmet liner according to an aspect of the invention; 
         FIGS. 4 and 5  are diagrammatic representations of the adjustability of the helmet liner shown in  FIG. 2A ; and 
         FIG. 6 and 7  are diagrammatic representations of the adjustability of the helmet liner shown in  FIG. 2A ; 
         FIGS. 8 and 9  are diagrammatic representations of the adjustability of the helmet liner shown in  FIG. 2B ; 
         FIG. 10A  is a cross-sectional view of the helmet liner taken along lines X-X of  FIG. 3  according to one aspect of the invention; 
         FIG. 10B  is a cross-sectional view of the helmet liner taken along lines X-X of  FIG. 3  according to another aspect of the invention; 
         FIG. 11  shows a schematic/cross-sectional view demonstrating how the helmet liner is adjustably fit to any user&#39;s head; and 
         FIG. 12  is another schematic/cross-sectional view demonstrating the operation of the adjustable helmet liner according to an aspect of the invention. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Referring to  FIG. 1 , there is shown a top view of the liner  10  according to an aspect of the invention. Liner  10  includes a forehead headband cushioning strip  18  having left and right portions  20   a  and  20   b , respectively. The forehead headband strip  18  is connected to the crown portion cushioning strip  12  through a center hinge like connection  15 . Opposing oval cutouts  16   a  and  16   b  define the hinge like flap/connection  15  between the forehead headband strip  18  and the crown portion cushioning strip  12 . These opposing oval cutouts  16   a  and  16   b  enable the forehead headband cushioning strip  18  to be wrapped around a user&#39;s forehead at various diameters. 
     The crown portion cushioning strip  12  includes left and right portions  14   a  and  14   b , respectively. The crown portion cushioning strip  12  is connected to the headband cushioning strip  18  in the front and has a similar hinge-like connection  29  to the rear cushioning strip  30 . A pair of opposed mirror image J-shaped cutouts  26   a  and  26   b  define the rear hinge like flap/connection  29  therebetween. The J-shaped cutouts  26   a  and  26   b  help form a C-shaped rear cushioning strip  30  having bulb like extensions  27   a  and  27   b  at each end of the C-shape (See  FIG. 3 ). The J-shaped cutouts  26   a  and  26   b  interlock with the C-shaped rear cushioning strip  30  when the liner  10  is laid flat as shown in  FIGS. 1-3 . 
     The upper, or helmet engaging, side  102  of liner  10  is made of fabric that preferably includes a small loop structure for adhering the same within a helmet and receiving the adjustment straps, in a hook and loop type fastening arrangement. Other suitable known types of fabrics may also be implemented for the upper side of the liner  10  without departing from the spirit of the invention. 
       FIG. 2   a  shows the underside, or lower head engaging side, of the liner  10  according to an aspect of the invention. The underside of the liner can be any suitable material and need not be the same fabric as the upper helmet engaging side. Since the underside of the liner  10  will be in contact with the user&#39;s head, it is possible that heat and moisture generated by the wearer&#39;s head can aide in the growth of bacteria within the helmet, and in particular on liner  10 . As such, it is contemplated to treat and/or manufacture the underside of liner  10  with a biocidal agent or material that will prevent the growth of bacteria, mildew and/or fungus. The biocidal agent or other anti-microbial material can be of any suitable known type. By way of example, an anti-microbial material such as X-STATIC®, manufactured by Noble Fiber Technologies, Inc., can be incorporated into the fabric underside of liner  10  to prevent bacteria growth. In a further example, a synthetic iodinated resin that can be used for the eradication of microorganisms is marketed under the registered trademark TRIOSYN®, by the Canadian company Triosyn Corporation. This resin is a demand-release agent that delivers germicidal iodine to harmful microorganisms. Other anti-microbial and/or biocidal materials and/or elements may also be incorporated into the head engaging side of the liner  10  without departing from the spirit of the invention. 
     In accordance with one aspect of the invention, the liner  10  is manufactured into a single piece provided with arms and spaces (i.e., the opposing oval cutouts  16   a  and  16   b  and J-shaped cut outs  26   a  and  26   b ), which, in conjunction with the straps  22   a ,  22   b ,  34   a  and  34   b , respectively, provide the infinite adjustment of the liner  10 . As will be explained in further detail with reference to embodiments of  FIGS. 4-7 , the strategic positioning of the straps  22   a ,  22   b ,  34   a  and  34   b  on the respective ends of the liner, operate in conjunction with the integrated spaces to provide the infinite field adjustment of the liner  10  according to the invention. 
     The straps  22   a  and  22   b  are positioned (and connected  21   a  and  21   b ) on the respective ends  20   a  and  20   b , of the forehead headband cushioning strip  18  such that the particular placement of the straps onto the right and left crown portions  14   a  and  14   b , in conjunction with the shapes of the integrally formed spaces/oval cutouts  16   a  and  16   b  have a dramatic effect on the ability to adjust the liner to fit the user&#39;s head. 
       FIGS. 4-7  show the varying size adjustment capabilities of the liner  10  according to the present invention. As will become evident in the following description, the angles θ 1  and θ 2  vary depending on the size of the wearer&#39;s head. The smaller the angles θ 1  and θ 2 , the larger the wearer&#39;s head, and vice versa. 
     In the example shown in  FIGS. 4 and 6 , the forehead headband cushioning strip  18  is secured using straps  22   a  (not shown) and  22   b . The strap  22   b  is connected at a point  21   b  on end  20   b  such that when the strap is pulled back toward the rear portion in a direction that is substantially parallel with the lower end  14   b  of the right crown portion, a space is maintained between the end  20   b  and  14   b , while the integrally formed space  16   b  is slightly deformed to accommodate the “pull back” of the end portion  20   b  of the forehead cushioning strip  18 . 
     Referring to  FIGS. 4-7 , it is apparent that the angle at which strap  22   b  is “pulled back” with respect to the end  14   b , has a direct effect on the physical size of the integrally formed space  16   b  (i.e. oval cut out), and thereby the size of the liner  10  on the user&#39;s head. This same concept holds true for the all straps  22   a ,  22   b ,  34   a  and  34   b .  FIG. 7  illustrates via dashed lines how the change in angle orientation of the strap  22   b  with respect to the end of portion  14   b  of the crown cushioning portion  12  results in an infinite adjustability of the same. When strap  22  is “pulled back” at an upward angle with respect to end portion  14   b , the oval cutout  16   b  shrinks as the end  20   b  of the forehead cushioning strip  18  is brought closer to end  14   b  of the crown cushioning strip  12 . 
     Strap  34   b  is positioned/connected  33   b  on end  32   b  such that when “pulled forward” in a manner that is substantially parallel with end  14   b  and adhered to the same, the two ends  32   b  and  14   b  can be brought together to fit the rear portion  30  of the liner  10  to the user&#39;s head. Simply “pulling forward” straps  34   a  and  34   b  straight across, or at an upward angle, with respect to end  14   b  will result in the curved bulb portions  27   a  and  27   b  of the C-shaped rear cushioning strip  18  being wrapped into the lower part of the J-shaped cutouts  26   a  and  26   b , respectively, as the J-shaped cutouts collapse into the hemispherical configuration on the wearer&#39;s head. 
     The arcuate shapes  28   a  and  28   b  of the inside of the J-shaped spaces  26   a  and  26   b , in addition to the curvature of the bulb portions  27   a  and  27   b  are designed such that when the liner  10  is disposed on different size heads, the rear cushioning strip  30  can be completely adapted to fit the user, without any complex fitting arrangements or configurations. Furthermore, the Figures illustrate that throughout the range of size fittings, cutouts  16   a ,  16   b ,  26   a ,  26   b  provide a series of ventilation apertures through the liner. These ventilation apertures are well-spaced, with respect to a crown of the wearer. In certain fitting configurations, the ventilation apertures form channels that extend downwardly to the lower edge of the liner. Thus the geometry of the liner is designed for extreme comfort by providing infinite adjustability and ventilation. The ventilation apertures remain well-spaced even when the liner is collapsed to its smallest fitting size. 
     As shown in  FIGS. 4 and 6 , the liner  10  is disposed on a user&#39;s head that is typically larger than the average head.  FIGS. 5 and 7  show the liner  10  disposed on a smaller user&#39;s head with respect to  FIGS. 4 and 6 . It is apparent that when liner  10  is disposed on a larger head ( FIGS. 4 and 6 ), the angle θ 1 ˜65° and θ 2 ˜50°, while compared to the smaller head embodiments of  FIGS. 5 and 7 , where θ 1 ˜70° and θ 2 ˜60°. 
     FIGS.  2 B and  8 - 9  show another embodiment of the liner  10  according to the present invention. In this embodiment, adjustment straps  22  and  34  are positioned substantially parallel with the ends  14  of the crown cushioning strip  12  and extend outwardly therefrom toward the front and rear cushioning strips  18  and  30 , respectively. As shown in  FIGS. 8-9 , the front end  20   b  of the front cushioning strip  18  is pulled back toward the end  14   b  of the crown cushioning strip  14 , and strap  22   b  engages the fabric surface of the upper side of end  20   b . A similar fitting is made for the rear cushioning strip  18 , where end  32   b  of cushioning strip  30  is moved forward toward end  14   b  and when fit to the wearer&#39;s head, strap  34   b  engages and secures the fitting space relationship between the crown cushioning strip  12  and the front and rear cushioning strips  18  and  30  respectively. 
     The embodiment of FIGS.  2 B and  8 - 9  is a much simpler implementation of straps  22  and  34  to the liner and allows for a quicker application by disposing both front  22  and rear  34  straps to the same portion of the liner (i.e., the crown cushioning strip  14 ). 
     FIGS.  10 A and  11 - 12  show the cross-section of the liner  10  according to an embodiment of the invention. In particular,  FIG. 10A  shows the liner  10  having multiple internal foam pad configurations. By way of example, the front cushioning strip  18  ( FIG. 10A and 10B ), includes a lower head engaging foam layer  10   a  and an upper, helmet engaging foam layer  10   b.    
     Lower (head engaging) foam layer  10   a  is selected for comfort and is preferably made of a visco-elastic or any other suitable “memory” type foam. Examples of such products are described in U.S. Pat. Nos. 5,919,395 and 6,051,624 and 6,391,935. These three patents are incorporated herein by reference thereto, for the purpose of providing support for the composition and characteristics of certain foams. Upper foam layer  10   b  is preferably made of a supportive foam such as, for example, a urethane foam. By using a supportive urethane foam  10   b  on the helmet engaging side, not only does the liner provide more support to the wearer, but the urethane foam also functions to provide stability to the more pliable memory foam layer  10   a . One example of urethane foam that can be used for this application is SENSIFOAM® distributed by Creative Foam Corporation of Michigan. Other suitable known urethane foams may also be used without departing from the spirit of the invention. 
     In a practical embodiment each foam layer  10   a  and  10   b  is less than one inch thick. Upper and lower foam layers  10   a  and  10   b  may be bonded to each other and disposed within a cloth/fabric casing  100 , having certain characteristics, discussed herein. In addition to pairing the foams to balance comfort, stability and protection, the foams are selected for their broad temperature operating ranges. This means the foam will not harden in extreme cold and the foam will not soften in extreme heat. In other words, the foam hardness and pliability are substantially temperature insensitive within the range of temperatures that it will be exposed to. The predictable behavior and feel of the foam under different ambient conditions contributes to wearer comfort. 
       FIG. 11  shows the end  14   b  of the crown cushioning portion  12  as it would be positioned inside a helmet.  FIG. 12  shows the configuration of the front  20   a  and rear  32   a  portions of the respective cushioning parts. In achieving the infinite adjustability of the liner  10 , the opposing oval cutouts  16   a  and  16   b , and the J-shaped cutouts  26   a  and  26   b  in conjunction with the C-shaped rear cushioning strip  30  operate with the positioning of the straps  22  and  34  with respect to the corresponding portion  14  of the liner  10 . As shown in dotted configuration, the positions of the straps  22  and  34  with respect to the crown portion ends  14  changes the shape of the integrally formed spaces  16  and  26  to infinitely accommodate the size of any users head. By way of the example shown, the bulbous end  27   a  of the rear cushioning strip  30  is pulled up into the J-shaped cutout  26   a  when strap  34   a  is pulled upward at an angle with respect to portion  14   b . This positioning of the strap  34   a  further causes the C-shape of the end  27   a  to further interlock with the J-shaped cutout  26   a , and makes the J-shape cutout smaller in order to accommodate a smaller wearer&#39;s head. The position of the front portion  20   a  of the forehead cushioning strip  18  is also dependent on the position of strap  22   a  with respect to the end  14   a  of the crown cushioning strip  18 . As shown in the dotted configuration, when strap  22   a  is pulled at an upward angle with respect to portion  14   a , the oval cutout  16   a  collapses (i.e. shrinks) to accommodate the end  20   a  and allow the same to be secured against the wearer&#39;s head. 
     In other words, during fitting, hinge-like flap connections  15  and  29  flex in the same downward direction to transform the flat liner  10  into a semi-circular shape, as if the liner was draped over a cylinder. Next, on the forehead side, portions  20   a  and  20   b  along with crown portions  14   a  and  14   b , fold inward toward each other and create the front half of the hemi-spherical shape required to fit onto the wearer&#39;s head. This second degree of movement causes oval cutouts  16   a  and  16   b  to shrink as side and crown portions connect together, thus causing the liner  10  to take on a hemi-spherical shape around the wearer&#39;s spherical shaped head. On the rear side, bulbs  27   a  and  27   b  also fold inward toward crown portions  14   a  and  14   b , thus forming the rear half of the hemi-spherical shape. This further degree of movement causes J shaped cutouts  26   a  and  26   b  to collapse into smaller, arcuate shaped spaces. 
       FIG. 10B  shows an alternate pad configuration. The figure schematically shows front (brow) portion  18 , central (crown) portion  12 , and rear portion  30 . A discrete padset is disposed within each of the three portions shown. In the vicinity of hinge sections  15  and  29  the front, middle and rear padsets are tapered to facilitate conforming the flat layers to a head shape without bunching up. The segmented pad configuration lends itself to customizing the type, number and thickness of each pad layer. In one example of customized thickness, we show the padset in rear portion  30  to be thicker then the other two portions. The pads may be stitched to fabric casing  100  to hold them in place. Discrete padsets may also be disposed in crown portions  14   a  and  14   b . This would provide a total of 4 padsets surrounding the central padset of portion  12 . Tapered ends may be provided at any location where two discrete padsets meet. 
     Through field experience, increasing the thickness of the rear cushioning strip/portion  30  not only provides an intermediate sizing configuration to further optimize individual fits, but more importantly, serves to bias the wearer&#39;s (fitee&#39;s) head forward within the helmet which has the beneficial effect of improving/optimizing the wearer&#39;s field of view (FOV) of the outside world from the helmet. 
     While there have been shown, described and pointed out fundamental novel features of the invention as applied to preferred embodiments thereof, it will be understood that various omissions, substitutions and changes in the form and details of the methods described and devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, it is expressly intended that all combinations of those elements and/or method steps which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Moreover, it should be recognized that structures and/or elements and/or method steps shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed, described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.