Abstract:
A foldable vehicle wheel traction apparatus is disclosed that includes four traction devices having a regular lattice structure. Each traction device is hingeably connected one to the other to permit the traction devices to be folded one on another with easy storage. The hingeable apparatus connected the traction devices permit minimal lateral movement, which allows the traction devices to be more easily maneuvered when being put in use. The ability of the traction apparatus to support the weight of the wheel is enhanced by the regular lattice structure of each traction device formed by the traction devices elongated lateral members and elongated cross members. In one embodiment, the cross members are composed of, or coated with materials that heat up when the vehicle wheel contacts and spins on the cross member, thereby promoting melting of snow or ice. In yet another embodiment, the shape of the cross-section of the cross members is chosen so that the cross member removes excess mud or snow adhering to the wheel.

Description:
FIELD OF INVENTION 
       [0001]    This invention relates to foldable vehicle wheel device for a wheel bogged on relatively slippery surface. Particularly, the invention relates to a vehicle anti-slip device that is foldable for easy storage and geometrically constructed for maximum desired load bearing. 
       BACKGROUND 
       [0002]    It is not uncommon for a wheeled vehicle to become immobilized in shifting or otherwise slippery surface. The prior art is includes examples of apparatus for providing mobility to the wheeled vehicle in these conditions. These prior art devices are typically either of a mat arrangement or a framed apparatus arrangement positioning between the drive train wheel of the vehicle and the shifting surface for fixing the vehicle relative to the surface. 
         [0003]    U.S. Pat. Nos. 3,640,459; 3,749,309; 4,261,510 and 5,439,171 are typical examples of the mat arrangements found in prior art traction devices. Traction devices with a mat arrangement are predominately a flat or curved surface that is used to cover the shifting surface. In this way, the mat provides friction and traction between the wheel and the shifting surface. 
         [0004]    Prior art traction mats are deficient in that the mat&#39;s predominately flat surface catches the build-up of loose material dislodged from the shifting surface and lodged in tracks of the wheel. Portions of the shifting surface on which the wheeled vehicle rested is deposited on the flat surface of the mat thereby creating a secondary shifting surface of the same composition. The wheel that was once immobilized on the shifting surface would then be immobilized on the secondary shifting surface formed between the wheel and the mat&#39;s flat surface. 
         [0005]    Framed traction devices are typically composed of various frame shapes. For example, U.S. Pat. No. 6,129,289 features a traction device with a U-shaped frame. The U-shaped frame includes a plurality of traversing braces each having downwardly facing cleats to engage the shifting surface. U.S. Pat. No. 3,878,988 is another U-shaped frame traction device with traversing braces and downwardly facing cleats. The traversing braces of the device disclosed in the &#39;988 patent are curved to fit into engagement with laterally traversing wheel tread cavities. U.S. Pat. No. 4,300,722 discloses another example of a framed traction device comprising a unitary elongated stamped metal structure that is generally rectangular but tapers forwardly and inwardly at one end. The upper surface of the device is flat and includes rectangular openings. The device upper surface includes upwardly extending gripping flanges while the lower surface includes V-shaped gripping lugs. U.S. Pat. No. 6,520,420 is another exemplary prior art frame traction device. The frame in this traction device is rectangular shaped and includes a plurality of traversing braces such that the openings created by the brace placement supplies rectangular openings. 
         [0006]    The prior art framed traction devices are deficient in that their respective structures offer limited load bearing capacity, and proper useful traction surface, 
         [0007]    What is needed is a traction device whose construction is minimilized for optimal load bearing and easy storage. 
       SUMMARY OF INVENTION 
       [0008]    In accordance with one embodiment, a foldable vehicle wheel traction device is taught that comprises:
       a. a first traction device having a lattice structure of width  2   d  and length  5   d , said first traction device having a first elongated cross member at a first end of said first traction device and a second elongated cross member at a second end of said first traction device, said first traction device further including four middle elongated cross members, wherein adjacent middle elongated cross members of the four middle elongated cross members are positioned a distance d from the next adjacent middle elongated cross members, and wherein the first of said four middle elongated cross member is a distance d from said first elongated cross member and said fourth of said four middle elongated cross members is a distance d from said second elongated cross member,
           said first traction device including a first elongated lateral member of length  5   d , a second elongated lateral member of length  5   d , and a middle elongated lateral member of length  5   d  intermediate to said first elongated lateral member and said second elongated lateral member, said first elongated lateral member connected to a first end of said first elongated cross member, said second elongated cross member, and said four middle elongated cross members, said second elongated lateral member connected to a second end of said first elongated cross member, said second elongated cross member, and said four middle elongated cross members, and wherein said middle elongated lateral member is connected to said first elongated cross member, said second elongated cross member, and said four middle elongated cross members, wherein said middle elongated lateral member is a distance d from said first elongated lateral member and said second elongated lateral member;   
           b. a second traction device hingeable coupled to said first traction device, wherein said hingeable coupling permits lateral movement of not more than about 1.5 inches, said hingeable coupling further permitting said first traction device to be folded onto said second traction device, and wherein said second traction device has a lattice structure of width  3   d  and length  5   d , said second traction device having a first elongated cross member at a first end of said first traction device and a second elongated cross member at a second end of said second traction device, said second traction device further including four middle elongated cross members, wherein adjacent middle elongated cross members of the four middle elongated cross members are positioned a distance d from the next adjacent middle elongated cross members, and wherein the first of said four middle elongated cross member is a distance d from said first elongated cross member and said fourth of said four middle elongated cross members is a distance d from said second elongated cross member, said second traction device including a first elongated lateral member of length  5   d , a second elongated lateral member of length  5   d , a first middle elongated lateral member of length  5   d  intermediate to said first elongated lateral member and said second elongated lateral member, and a second middle elongated lateral member of length  5   d  intermediate to said first middle elongated lateral member and said second elongate lateral member, said first elongated lateral member connected to a first end of said first elongated cross member, said second elongated cross member, and said four middle elongated cross members, said second elongated lateral member connected to a second end of said first elongated cross member, said second elongated cross member, and said four middle elongated cross members, and wherein said first middle elongated lateral member is connected to said first elongated cross member, said second elongated cross member, and said four middle elongated cross members, said second middle elongated lateral member is connected to said first elongated cross member, said second elongated cross member, and said four middle elongated cross members, wherein said first middle elongated lateral member is a distance d from said first elongated lateral member and said second middle elongated lateral member is a distance d from said first middle elongated lateral member and said second elongated lateral member;   c. a third traction device hingeable coupled to said second traction device, wherein said hingeable coupling permits lateral movement of not more than about 1.5 inches, said hingeable coupling further permitting said second traction device to be folded onto said third traction device, and wherein said third traction device has a lattice structure of width  3   d  and length  5   d , said third traction device having a first elongated cross member at a first end of said first traction device and a second elongated cross member at a second end of said third traction device, said third traction device further including four middle elongated cross members, wherein adjacent middle elongated cross members of the four middle elongated cross members are positioned a distance d from the next adjacent middle elongated cross members, and wherein the first of said four middle elongated cross member is a distance d from said first elongated cross member and said fourth of said four middle elongated cross members is a distance d from said second elongated cross member,
           said third traction device including a first elongated lateral member of length  5   d , a second elongated lateral member of length  5   d , a first middle elongated lateral member of length  5   d  intermediate to said first elongated lateral member and said second elongated lateral member, and a second middle elongated lateral member of length  5   d  intermediate to said first middle elongated lateral member and said second elongate lateral member, said first elongated lateral member connected to a first end of said first elongated cross member, said second elongated cross member, and said four middle elongated cross members, said second elongated lateral member connected to a second end of said first elongated cross member, said second elongated cross member, and said four middle elongated cross members, and wherein said first middle elongated lateral member is connected to said first elongated cross member, said second elongated cross member, and said four middle elongated cross members, said second middle elongated lateral member is connected to said first elongated cross member, said second elongated cross member, and said four middle elongated cross members, wherein said first middle elongated lateral member is a distance d from said first elongated lateral member and said second middle elongated lateral member is a distance d from said first middle elongated lateral member and said second elongated lateral member; and   
           d. a fourth traction device hingeable coupled to said third traction device, wherein said hingeable coupling permits lateral movement of not more than about 1.5. inches, said hingeable coupling further permitting said fourth traction device to be folded onto said third traction device, and wherein said fourth traction device has a lattice structure of width  3   d  and length  5   d , said fourth traction device having a first elongated cross member at a first end of said first traction device and a second elongated cross member at a second end of said third traction device, said fourth traction device further including four middle elongated cross members, wherein adjacent middle elongated cross members of the four middle elongated cross members are positioned a distance d from the next adjacent middle, elongated cross members, and wherein the first of said four middle elongated cross member is a distance d from said first elongated cross member and said fourth of said four middle elongated cross members is a distance d from said second elongated cross member,
           said fourth traction device including a first elongated lateral member of length  5   d , a second elongated lateral member of length  5   d , a first middle elongated lateral member of length  5   d  intermediate to said first elongated lateral member and said second elongated lateral member, and a second middle elongated lateral member of length  5   d  intermediate to said first middle elongated lateral member and said second elongate lateral member, said first elongated lateral member connected to a first end of said first elongated cross member, said second elongated cross member, and said four middle elongated cross members, said second elongated lateral member connected to a second end of said first elongated cross member, said second elongated cross member, and said four middle elongated cross members, and wherein said first middle elongated lateral member is connected to said first elongated cross member, said second elongated cross member, and said four middle elongated cross members, said second middle elongated lateral member is connected to said first elongated cross member, said second elongated cross member, and said four middle elongated cross members, wherein said first middle elongated lateral member is a distance d from said first elongated lateral member and said second middle elongated lateral member is a distance d from said first middle elongated lateral member and said second elongated lateral member.   
               
 
         [0016]    In accordance with one embodiment of the present invention, adjacent cross members simultaneously support the weight of the wheel as it traverses the foldable vehicle wheel traction device. Weight is supported by two at the same time generating more pulling power. 
         [0017]    In another embodiment of the present invention, cross members remove material stuck to the exterior surface of the wheel when the wheel is in contact with, and spins on the cross member. 
         [0018]    In yet another embodiment, the cross members of the device heat up during use. The cross members are comprised of or coated with a polymer that generates heat when the vehicle wheel contacts and spins on the surface of the cross member. 
         [0019]    In still another embodiment of the invention, the material chosen is chosen so that the contact between the wheel and the cross members results in increased heat exchange for when the shifting material is ice. This promotes melting of the ice. 
     
    
     
       DRAWING FIGURES 
         [0020]    These and other more detailed and specific features of the present invention are more fully disclosed in the following specification, reference being had to the accompanying drawings, in which: 
           [0021]      FIG. 1  is an overhead view of an exemplary foldable vehicle wheel traction apparatus in accordance with the present invention. 
           [0022]      FIG. 2  is an overhead view of a first traction device of an exemplary foldable vehicle wheel traction apparatus in accordance with the present invention. 
           [0023]      FIG. 3  is an overhead view of an exemplary second, third, or fourth traction device of an exemplary foldable vehicle wheel traction apparatus in accordance with the present invention. 
           [0024]      FIG. 4  depicts an exemplary traction apparatus of the present invention in operation. 
           [0025]      FIG. 5  depicts an exemplary traction apparatus of the present invention in partial folded arrangement. 
           [0026]      FIG. 6  depicts an exemplary traction apparatus of the present invention in substantially folded arrangement. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0027]    The present may be described with reference to the figures or drawings depicted herein. However, it is to be understood that the drawings are exemplary ad only intended to aid the reader in understanding the inventive nature of the traction apparatus. Moreover, for brevity, notions and principles of friction, loose or slippery soil, wheel erosion, and soil consistency will not be discussed herein in detail. 
         [0028]      FIG. 1  depicts an exemplary foldable vehicle wheel traction apparatus  100  in accordance with the present invention. As shown, traction apparatus  100  includes four traction device  102  and three traction devices  104  in linear adjacent arrangement. Traction device  102  is of a narrower in width than traction device  104 . Each traction device is coupled to the next traction device using a hinging device  116  permitting a traction device to be folded onto an adjacent traction device (discussed with relation to  FIGS. 5 and 6 ). 
         [0029]    With respect to  FIG. 2 , a first traction device  102  is depicted. First traction device  102  comprises a first elongated lateral member  120  in parallel arrangement with a second elongated lateral member  118 . First elongated lateral member  120  is positioned a distance  2   d  from second elongated lateral member  118 . Intermediate first elongated lateral member  120  and second elongated lateral member  118  is a first middle elongated lateral member  122 . First middle elongated lateral member  122  is positioned parallel to and equidistant from first elongated lateral member  120  and second elongated lateral member  118 . For example, first middle elongated lateral member  122  is distance d from first elongated lateral member  120  and a distance d from second elongated lateral member  118 . In accordance with one embodiment of the invention, first elongated lateral member  120 , first middle elongated lateral member  122 , and second elongated lateral member  118  are of the same length, width, shape and composition. 
         [0030]    First traction device  102  further includes a first end elongated cross member  108  a first end of first traction device  102 . First elongated cross member  108  has a length  2   d . First elongated cross member  108  couples first elongated lateral member  120 , first middle elongated lateral member  122 , and second elongated lateral member in fixed arrangement. 
         [0031]    First traction device  102  further includes a second elongated cross member  110 . Second middle elongated cross member  110  is of a length  2   d . Second elongated cross member  110  is position in parallel arrangement to first elongated cross member  108 . Second elongated cross member  110  is positioned distance l from first elongated cross member  108 . Second elongated cross member  110  couples first elongated lateral member  120 , first middle elongated lateral member  122 , and second elongated lateral member  118  in fixed arrangement. In one embodiment, first elongated cross member  108  is positioned a distance  5   d  from second elongated cross member  110 . 
         [0032]    First traction device  102  further comprises four middle elongated cross members  132  each of length  2   d . Each of middle elongated cross members  132  is in parallel arrangement to first middle elongated cross member  108  and second elongated cross member  110 . A first middle elongated cross member  132  is positioned a distance d from first elongated lateral member  108 . A second middle elongated cross member  132  is positioned a distance d from first middle elongated cross member  132 . The third middle elongated cross member  132  is positioned a distance d from the second middle elongated cross member  132 . The fourth middle elongated cross member  132  is positioned a distance d from third middle elongated cross member  132 . And, fourth middle elongated cross member  132  is positioned a distance d from the second elongated cross member  110 . The middle elongated cross members  132  couple first elongated lateral member  120 , first middle elongated lateral member  122 , and second elongated lateral member  118  in fixed arrangement. In one exemplary embodiment, elongated lateral members and the elongated cross members are of the similar or identical cross-section. 
         [0033]    Second, third and fourth traction devices  104  are of similar configuration each to one another. As such, a second traction device  104  is depicted in  FIG. 3  by way of illustration. Second traction device  104  comprises a first elongated lateral member  126  in parallel arrangement with a second elongated lateral member  124 . First elongated lateral member  126  is positioned a distance  3   d  from second elongated lateral member  124 . Intermediate first elongated lateral member  126  and second elongated lateral member  124  is a first middle elongated lateral member  128  and a second middle elongated lateral member  130 . First middle elongated lateral member  128  is positioned parallel to and equidistant from first elongated lateral member  126  and second middle elongated lateral member  130 . Second middle elongated lateral member  130  is positioned parallel to and equidistant from first middle elongated lateral member  128  and second elongated lateral member  124 . For example, first middle elongated lateral member  128  is distance d from first elongated lateral member  126  and a distance d from second middle elongated lateral member  130 . Second middle elongated lateral member  130  is distance d from first middle elongated lateral member  128  and a distance d from second elongated lateral member  124 . In accordance with one embodiment of the invention, first elongated lateral member  126 , first middle elongated lateral member  128 , second middle elongated lateral member  130  and second elongated lateral member  124  are of substantially similar or identical cross-section. In accordance with yet another embodiment of the invention, first elongated lateral member  126 , second elongated lateral member  124 , first middle elongated lateral member  128 , and second middle elongated lateral member  130  are of substantially identical length or identical length. For example, second traction device  104  elongated lateral members each have a length of  5   d.    
         [0034]    Second, third, and fourth traction devices  104  further include a first elongated cross member  112 , a second elongated cross member  114  and four middle elongated cross members  134 , all of which are in parallel arrangement one to the other. In one embodiment, second traction device  104  cross members have identical cross section and a length  3   d . The first middle elongated cross member  134  is a distance d from the second middle elongated cross member  134  and first elongated cross member  112 ; second middle elongated cross member  134  is a distance d from the third elongated cross member  134 ; the third elongated cross member is a distance d from the fourth middle elongated cross member  134 ; and fourth middle elongated cross member  134  is a distance d from second elongated cross member  114 . Elongated cross members  112 ,  114  and middle elongated cross members  134  couple first elongated lateral member  126 , first middle elongated lateral member  128 , second middle elongated lateral member  130 , and second elongated lateral member  124  in fixed arrangement. 
         [0035]    As shown in  FIGS. 1 ,  5  and  6 , traction devices  102  and  104  are coupled in a movable hingeable arrangement so that traction devices  102  and  104  may be folded one on top of the other. Traction devices  102  is coupled to traction device  104  via flexible hinging apparatus  116 , which allows some but minimal lateral movement. In one preferred embodiment, hinging apparatus  116  permits lateral movement of no more than 1.5 inches. For example, hinging apparatus  116  may be a chain link as shown in the drawing figures. The overall length of the hinging apparatus  116  is chosen so that the minimal 1.5 inch lateral movement is permitted. Additionally, the length of the hinging apparatus  116  is chosen so that the adjacent cross members of adjacent traction devices are permitted to simultaneously bear the weight of wheel  200 . For example, where first traction device  102  is hingeably connected to second traction device  104  at second elongated cross member  114  and first elongated cross member  108  by hinging apparatus  116 , then second elongated cross member  114  and first elongated cross member  108  are arranged at a distance one from the other allowing both the second elongated cross member  114  and the first elongated cross member  108  to simultaneously bear the load of wheel  200 . By simultaneous what may be meant is that as wheel  200  traverses from first elongated cross member  108  to second elongated cross member  114  equally bear the load of wheel  200  as wheel  200  moves from first traction device  102  to second traction device  104 . Similarly, when wheel  200  traverses from second traction device  104  to third traction device  104 , hinging apparatus  116  between second traction device  104  and third traction device  104  is of appropriate length to allow wheel  200  to be simultaneously supported by the adjacent cross members of the second and third traction devices  104 . 
         [0036]    As seen in  FIGS. 5 and 6 , first traction device  102  folds at a hinging apparatus  116  relative to second traction device  104  such that second traction device  104  is positioned adjacent to second traction devices  104 , third traction device  104  folds at a hinging apparatus  116  with respect to second traction device  104  such that third traction device  104  may rest adjacent to second traction device  104 , and first traction device  102  folds at a hinging arrangement  116  with respect to second traction device  104 , such that first traction device  102  may rest adjacent to second traction device  104 . 
         [0037]    Traction apparatus  100  may be constructed of a rigid material selected where the load bearing capacity of each traction device  102 ,  104  is calculated based on material composition, and which takes into account the lattice structure resulting from the arrangements of the elongated members and the cross members of each traction device. A suitable calculation considers that the lattice structure is composed of squares of side length d, and the length of each traction device  102  and  104  are of a length  5   d.    
         [0038]      FIG. 4  depicts foldable vehicle wheel traction device  100  in operation.  FIG. 4  depicts an ordinary vehicle wheel  200  trapped in a slipper surface  204  of surface  202 . To aid in understanding the invention, it is understood that wheel  200  is bogged in a surface which does not provide wheel  200  proper traction to propel a vehicle (not shown) attached to wheel  200 . 
         [0039]    Each elongated lateral member and elongated cross member may be substantially oval, circular or square in cross-section. In a preferred embodiment, the cross section of each cross member is chosen such that where there is superficial material, such as mud or snow, is attached to the exterior contacted by and removed by the cross member. For example, in use, first traction device  102  is placed in the slippery surface  204  adjacent to, and in contact with, wheel  200  such that wheel  200  may engage first traction device  102  at second elongated cross member  110 . Once wheel  200  is made to rotate, wheel  200  rotates up onto second elongated cross member  110 . If wheel  200  rotates or spins while in contact with second elongated cross member  110 , second elongated cross member  110  removes excess superficial material exterior to wheel  200  until wheel  200  is made to contact with second elongated cross member  110 . As wheel  200  rotates, material superficial to wheel  200  is removed by cross member  110  thereby providing traction of wheel  200  against traction device  102 . 
         [0040]    Once wheel  200  traverses upon second elongated cross member  110 , the wheel  200  moves onto fourth middle elongated cross member  132 , while still in contact with second elongated cross member  110 . In this way, the weight of wheel  200  is supported by two adjacent cross members simultaneously. This supporting of the wheel weight is repeated as wheel  200  traverses from one cross member to an adjacent cross member. Additionally, as wheel  200  traverses from first traction device  102  to second traction device  104 , the weight of the wheel  200  is supported by the cross member of first traction device  102  that is adjacent to traction device  104 , and the cross member of second traction device  104  adjacent to first traction device  102 . In a similar way, as wheel  200  traverses from second traction device  104  to third traction device  104 , the weight of the wheel  200  is supported by the cross member of third traction device  102  that is adjacent to second traction device  104 , and the cross member of second traction device  104  adjacent to third traction device  102 . Further still, the weight supporting process described herein is equally useful for when wheel  200  traverses from any one of the traction devices to an adjacent traction device. In one exemplary embodiment, the distance d is chosen to be 3 inches to facilitate the weight support and weight distribution properties described herein. In this way, as wheel  200  traverses the traction apparatus  200 , the wheel  200  is supported by at least two cross members simultaneously, thereby generating more pulling power than prior art traction apparatuses. 
         [0041]    In still another embodiment of the invention, the material chosen is chosen so that the contact between the wheel and the cross members results in increased heat exchange between the cross members and the wheel. The material may be a polymer, or may be coated with a polymer that heats up rapidly when wheel  200  spins on the cross member while in contact therewith. This is especially useful for when wheel  200  is mired in snow or ice. The spinning action of wheel  200  in contact with the coated cross member causes the cross member to heat up, thereby promoting melting of the ice or snow. As the snow or ice melts, friction between the wheel  200  and the cross member increases, and the traction of the wheel  200  on the traction apparatus  100  increases. 
         [0042]    Although the present invention has been described in considerable detail with reference to certain preferred embodiments thereof, other embodiments are possible. For example, although the invention is described with reference to a chain link hinging apparatus, other suitable hinging apparatus are suitable for use with this invention, so long as, such hinging apparatus permits the traction devices to be folded one over another for easy storage and also conforms to the minimal lateral movement as well. Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred embodiments contained herein, but includes equivalents thereof.