Abstract:
A steerable inflatable sled that includes a first inflatable segment, a second inflatable segment, and a predetermined articulation zone extending from the first inflatable segment to the second inflatable segment, the longitudinal axis of the sled extending through the first inflatable segment, said second inflatable segment and the articulation zone, when the sled is in motion on a surface, applying a force to the first inflatable segment sufficient to cause a bend at the predetermined articulation zone, changes the direction of travel of the sled.

Description:
BACKGROUND  
         [0001]    The invention relates to a steerable, inflatable sled.  
           [0002]    Sledding down a hill covered with snow at high speeds can be enjoyable until an obstacle appears in the path of travel and the rider has no ability to change the direction in which the sled is traveling. Many sleds have no mechanism for steering other than shifting the weight of the rider as the sled travels across the snow. Sleds such as long wooden toboggans, round metal discs, and plastic sheets tend to be made from rigid materials that are difficult to control. Sleds that have a physical steering mechanism are often heavy and rigid and include rigid metal runners that are difficult for the rider to manipulate. The rigid metal runners and steering mechanisms also tend to slow down the sled, at times to a point of standstill.  
           [0003]    Round inner tubes are often used for “tubing” down snow-covered hills. Round tubes have a natural tendency to travel along the “fall line” of the hill, changing direction of travel as the fall line, or contour, of the hill changes. Thus, the rider has little control over the direction of travel taken by the tube. This can be dangerous in light of the many hazards that may exist on a hill including trees, bumps, bushes, and other people sledding, tubing or sitting stationary on the hill.  
         SUMMARY  
         [0004]    In one aspect, the invention features a steerable inflatable sled that includes a first inflatable segment, a second inflatable segment, and a predetermined articulation zone extending from the first inflatable segment to the second inflatable segment, the longitudinal axis of the sled extending through the first inflatable segment, the second inflatable segment and the articulation zone, when the sled is in motion on a surface, applying a force to the first inflatable segment sufficient to cause a bend at the predetermined articulation zone, changes the direction of travel of the sled.  
           [0005]    In one embodiment, the cross sectional dimension of the articulation zone taken in a plane perpendicular to the longitudinal axis of the sled is less than the cross sectional dimension of the first inflatable segment taken in a plane perpendicular to the longitudinal axis of the sled near the first end of the first inflatable segment and less than the cross sectional dimension of the second inflatable segment taken in a plane perpendicular to the longitudinal axis of the sled near the first end of the second inflatable segment.  
           [0006]    In other embodiments, the bend experienced at the articulation zone when the force is applied to the first inflatable segment is in a direction substantially perpendicular to the longitudinal axis of the sled.  
           [0007]    In another embodiment, the sled further includes at least one runner attached to a first surface of the sled. In some embodiments, the runner is flexible. In one embodiment, the sled further includes a plurality of runners attached to a surface of the first inflatable segment. In other embodiments, further includes a plurality of runners attached to the sled, at least one of the runners extending from the first inflatable segment through at least a portion of the articulation zone. In some embodiments, the sled further includes a plurality of runners attached to the sled, at least one of the runners extending from the first inflatable segment through the articulation zone to the second inflatable segment.  
           [0008]    In another embodiment, the sled further includes a plurality of runners attached to a surface of the second inflatable segment. In other embodiments, the sled further includes a runner attached to a surface of the sled and extending from the first inflatable segment to the second inflatable segment. In some embodiments, at least one runner flexes when a force is applied to the first inflatable segment sufficient to cause a bend at the predetermined articulation zone. In another embodiment, at least one runner is plastic.  
           [0009]    In some embodiments, at least one of the first inflatable segment and the second inflatable segment includes a plurality of air chambers. In other embodiments, the first inflatable segment includes at least one air chamber and the second inflatable segment includes at least one air chamber, at least one air chamber of the first inflatable segment being in fluid communication with at least one air chamber of the second inflatable segment.  
           [0010]    In another embodiment, wherein the first inflatable segment includes an air chamber and the second inflatable segment includes an air chamber, wherein the air chamber of the first inflatable segment is not in fluid communication with the air chamber of the second inflatable segment.  
           [0011]    In one embodiment, the first inflatable segment is in fluid communication with the second inflatable segment through the articulation zone. In some embodiments, the articulation zone includes an air chamber. In other embodiments, the articulation zone includes a living hinge.  
           [0012]    In another aspect, the invention features a steerable sled including a first inflatable segment, a second inflatable segment; a predetermined articulation zone disposed between the first inflatable segment and the second inflatable segment, and a runner attached to at least a portion of the articulation zone. In one embodiment, the runner extends from the articulation zone to the first inflatable segment. In other embodiments, the runner extends from the first inflatable segment, through the articulation zone, to the second inflatable segment.  
           [0013]    The invention features an inflatable sled that is capable of being easily steered, slowed and, if desired, stopped by the user. The sled can be controlled so as to travel along a desired path including against the fall line of a hill. The sled can be steered by the rider with a low level of force relative to sleds made from heavy rigid materials with stiff relatively inflexible runners such as metal runners.  
           [0014]    The invention features an inflatable steerable sled that can be constructed for use on snow, water, ice or a combination thereof. In preferred constructions the sled is lightweight such that it can be easily transported by an individual in the inflated state.  
           [0015]    Other features and advantages will become apparent from the following description of the preferred embodiment and the claims. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]    [0016]FIG. 1 is a top view of an inflatable steerable sled.  
         [0017]    [0017]FIG. 2 is the bottom view of the sled of FIG. 1.  
         [0018]    [0018]FIG. 3 is a side view of a runner of the sled of FIG. 1.  
         [0019]    [0019]FIG. 4 is a side view of the sled of FIG. 1.  
         [0020]    [0020]FIG. 5 is a bottom view of a sled according to a second embodiment.  
         [0021]    [0021]FIG. 6 is a bottom view of a sled according to a third embodiment.  
         [0022]    [0022]FIG. 7 is a top view of a sled according to a fourth embodiment.  
         [0023]    [0023]FIG. 8 is a cross sectional view taken along line A-A of the sled of FIG. 7. 
     
    
       [0024]    For ease of reference, like elements are given the same reference numerals throughout the drawings.  
       DETAILED DESCRIPTION  
       [0025]    For ease of description, the inflatable sled will be described with reference to its use on a snow covered hill, although it is contemplated that the sled can be used on a variety of surfaces including, e.g., water and ice.  
         [0026]    The sled  10  includes an inflatable body  12  that includes a first segment  14  that forms the forward most (e.g., down hill) portion of the sled, a second segment  16  forming the rearward most (e.g., uphill) portion of the sled  10 , and an articulation zone  18  disposed between the first segment  14  and the second segment  16 , as illustrated in FIGS.  1 - 4 . The first segment  14  is contoured to include protuberances  28 . The bottom (e.g., snow contacting) surface  20  of the sled  10  includes runners  22  and the top (e.g., rider contacting) surface  24  of the sled  10  includes handles  26 .  
         [0027]    The sled  10  is capable of being steered by a rider positioned in a sitting or prone position on the sled  10 . The rider exerts a force against the first segment  14  of the sled  10  in the region of one of the protuberances  28   a ,  28   b  of the first segment  14 . Pushing against the sled in the area of the protuberance  28 , and optionally the handle  26 , where present, causes a bend at the articulation zone  18  in a region of the articulation zone  18  opposite the side of the sled against which the force was exerted. The force is preferably exerted in a downward (i.e., toward the surface on which the sled is riding) and outward (i.e., away from the rider) direction. When in the prone position, for example, the rider can exert a force using his or her hands or forearms in the region of one of the protuberances. The force causes the articulation zone to bend, and, where present, the runners  22  to flex, which causes a change in the direction of travel of the sled causing the sled  10  to turn. Pushing downward on the first segment  14  toward the surface (e.g., snow) on which the sled is riding increases the contact between the sled and the riding surface and allows the sled to turn more sharply. Alternatively, the rider can simultaneously push on the sled in the area of one protuberance (e.g.,  28   a ) and pull on the sled in the area of the other protuberance (e.g.,  28   b ) to effect a change in direction of travel of the sled. The protuberances  28   a ,  28   b  are preferably dimensioned to limit the extent of deflection of the first segment, which prevents “over steering” of the sled.  
         [0028]    The sled is constructed from a polymeric material including, e.g., polyvinylchloride, polyurethane, thermoplastic elastomer, natural and synthetic rubbers, and combinations thereof. The polymer can be reinforced with various components including, e.g., woven webs, nonwoven webs, fibers, filaments, and combinations thereof.  
         [0029]    The first segment  14  includes an arcuate portion, which preferably provides aerodynamic properties to the sled and low resistance to movement in deep snow. Alternatively the first segment could have a linear or squared-off end. The first segment  14  is contoured to include regions, i.e., protuberances  28 . Preferably the protuberances are dimensioned to provide an area on which a rider in the prone position with elbows bent can rest his or her elbows and forearms. Alternatively, a rider in a sitting position can rest his or her feet against regions  28 . The first segment  14  can be of a variety of shapes including, e.g., spade, triangle, and semicircle, and preferably is of a shape that enhances the aerodynamic properties of the sled. Preferably the sled has an arcuate end  32  at its leading end.  
         [0030]    The second segment  16  provides a platform on which a person can sit or lie (e.g., in a prone position facing down into the sled or in a position facing up and away from the surface of the sled). The second segment  16  is preferably generally rectangular but can be of a variety of shapes including, e.g., square, triangular, rhomboid, circular, elliptical, and hourglass.  
         [0031]    The predetermined articulation zone  18  is disposed between the first segment  14  and the second segment  16 . The articulation zone  18  can be inflatable and in fluid communication with the first segment  14  and the second segment  16 . Alternatively, the articulation zone can be a living hinge formed, e.g., by a sheet extending between the first inflatable segment and the second inflatable segment or by two plies bonded together. The articulation zone “necks in” relative to the first segment  14  and second segment  16 . That is, the articulation zone  18  has a smaller cross sectional dimension taken in a plane perpendicular to the longitudinal axis of the sled relative to both the cross sectional dimension of the region of the first segment near the articulation zone, and the cross sectional dimension of the second segment near the articulation zone. The articulation zone  18  provides a pivot about which the first segment  14  rotates when a force is exerted by the rider against at least one of the protuberances  28 .  
         [0032]    The first segment  14 , the second segment  16  and the articulation zone  18  of the inflatable body form a single air chamber  36  such that the segments  14 ,  16 ,  18  are in fluid communication with each other. The air chamber  36  includes a number of gusset walls  46  positioned to create structure within the air chamber and to impart rigidity to the inflatable body of the sled. The gusset walls  46  extend from the top wall  48  of the chamber to an opposite bottom wall  50  of the chamber. A gusset wall  46  in the air chamber can be formed by bonding a gusset wall to a top sheet and a bottom sheet. Alternatively, the chamber can include regions defined at least in part by a divider formed by bonding two portions (e.g., the top and bottom wall) of the outer wall of the inflatable body together. The gusset walls  46  extend along a portion of the longitudinal extent of the inflatable body to create multiple open cells in a single air chamber body. The gusset walls can extend either continuously or discontinuously along an extent of the air chamber. Alternatively, the gusset walls or dividers can be positioned along an entire extent of the chamber to create multiple closed cells, i.e., multiple separate air chambers. In one embodiment, the gusset walls or dividers extend along the entire length of the longitudinal extent to create multiple closed cells in the inflatable body.  
         [0033]    In other embodiments, the first segment  14 , the second segment  16  and the articulation zone  18  are at least two separate chambers such that the chamber(s) of the first segment and the chamber(s) of the second segment are not in fluid communication with each other. The separate chambers can have their own inflation/deflation port. The articulation zone, where inflatable, can be in fluid communication with the first segment, the second segments, or a combination thereof, or it can include a separate chamber.  
         [0034]    Runners  22  are attached to the snow-contacting surface  20  of the sled  10  as illustrated in FIGS.  2 - 6 . The runners  22  can be attached to at least a portion of the first segment  14 , the second segment  16 , the articulation zone  18  or any combination thereof. The runners  22  are elongated strips that are attached to the exterior surface of the sled to assist the movement of the sled over a surface. FIG. 3 illustrates a runner  22  that includes a base  40  and a protrusion  42  extending away from the base  40 . The base  40  is attached to the surface of the sled  10  such that the protrusion  42  extends away from the surface of the sled. The runners  22  can be attached to the surface of the sled in a variety of configurations. Referring to FIG. 2, the sled  10  includes a number of runners  22  attached to the first inflatable segment  14 , a number of runners attached to the second inflatable segment  16 , and a runner  22   b  extending from the first segment  14  through the articulation zone  18  to the second inflatable segment  16 .  
         [0035]    In another embodiment, a number of runners  22  are attached to the first and second segments, and one runner extends along the bottom surface  20  of the sled  10  from the first segment  14 , through the articulation zone  18  and along a major portion of the length of the second segment  16 , as illustrated in FIG. 6.  
         [0036]    In another embodiment, a number of runners  22  are attached to both the first inflatable segment  14  and the second segment  16 , as illustrated in FIG. 5.  
         [0037]    The runners  22  can be attached to the sled with any suitable attachment mechanism including, e.g., adhesive composition, high frequency welding, heat welding, stitching, mechanical fasteners and combinations thereof.  
         [0038]    The runners  22  can be made from a variety of materials including, e.g., plastic (e.g., flexible plastic), foam, metal and combinations thereof.  
         [0039]    The handles  24  and  26  of the sled are positioned on the sled to provide suitable grips for at least one rider. FIGS. 1 and 4, illustrates handle positioned near the protuberances  32  of the first segment  14 . The handles provide something on to which the rider can hold and can also provide a structure against which a rider can exert a force to assist in turning the sled.  
         [0040]    The sled can also include a handle  44  positioned near the terminal end of the first inflatable segment of the sled, as illustrated in FIG. 1. The handle  44  is preferably flexible is useful for a variety of functions including providing a device to grasp for pulling the sled (e.g., up a hill), balance to the rider, and steering assistance. When the sled  10  is in motion, the rider can pull on the handle  44  to assist the turning effort. In one embodiment, the rider hangs on to the handle  44  while exerting pressure on the protuberance region of the first segment  14 . The handle  44  can be made from a variety of materials including, e.g., rope, twine, plastic, webbing, and combinations thereof  
         [0041]    The handles can be attached to the sled with any suitable attachment mechanism including, e.g., adhesive composition, sonic welding, heat welding, stitching, mechanical fasteners and combinations thereof. The handles can be made from a variety of materials including, e.g., plastic (e.g., flexible plastic), rope, metal, and combinations thereof.  
         [0042]    Other embodiments are within the claims. One or more handles, for example, can be replaced with a ridge. When constructed for use on water, for example, the sled can include fins. Preferably the fins are positioned and dimensioned to provide steering control. The fins can extend from the runners and can exist in place of or in addition to the runners. The fins can extend away from the water-contacting surface of the sled such that they would be directed into the water. In one embodiment, the fins are attached to the first inflatable segment, the second inflatable segment, the articulation zone or a combination thereof. In one embodiment, fins are placed near the protuberances on the water-contacting surface of the sled.  
         [0043]    In another aspect, the sled is constructed (e.g., through molding, e.g., injection molding) from a flexible, cellular material. The cellular material is sufficiently rigid to support the weight of a rider and sufficiently flexible to permit flexure through the articulation zone. The runners, handles or a combination thereof, can be molded as an integral component of the body of the sled.