Abstract:
A manual access ramp including a frame, a platform slidably coupled to the frame, the platform being movable between a stowed position and a deployed position, and a first and second side fences coupled to the platform, the side fences being moveable between a stowed position and an deployed position.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority under  35  U.S.C. § 119 (e) to U.S. Provisional Patent Application No. 61/288,629 filed on Dec. 21, 2009. The content of the application is hereby incorporated by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to stowable access ramps, especially for aiding handicapped or elderly persons in the ingress and egress to and from vehicles and the like. 
       SUMMARY 
       [0003]    In some embodiments, the invention provides an access ramp assembly including a frame assembly and a platform assembly. The platform assembly is movable between a stowed position and a deployed position relative to the frame assembly. The platform assembly includes a platform and a pair of side fences. Each of the side fences is movable between a stowed position and a deployed position, the side fences being substantially perpendicular to the platform in the deployed position. The side fences include integral pull handles having apertures therein. 
         [0004]    In other embodiments, the invention provides an access ramp assembly including a frame assembly and a platform assembly. The frame assembly includes a pair of opposed parallel tracks in which side edges of the platform assembly are slidably received. The platform assembly is manually movable between a stowed position and a deployed position relative to the frame assembly by sliding the platform assembly along the tracks. An anti-jam timing assembly couples the frame assembly and the platform assembly. The timing assembly includes a cross shaft and a pair of opposed timing belts. The timing belts are engaged with a corresponding pair of gear wheels provided at opposite ends of the cross shaft. 
         [0005]    In yet other embodiments, the invention provides a manual access ramp including a frame having a first track and a second track, the first and second tracks being parallel to each other. The manual access ramp also includes a timing assembly having a cross shaft, a first timing belt and a second timing belt, the first timing belt being coupled to the first track, the second timing belt being coupled to the second track, and the cross shaft being coupled to the first timing belt and the second timing belt. In addition the manual access ramp includes a platform coupled to the first timing belt and the second timing belt, a first end of the platform being moveable along the first track and second track and a first and second side fences coupled to the platform, the side fences being moveable between a stowed position and an deployed position. 
         [0006]    Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is a perspective view of a manual access ramp assembly including a pair of side fences in the stowed position and showing the pair of side fences in the deployed position in phantom. 
           [0008]      FIG. 2  is a detail perspective view of the side fences of the manual access ramp assembly of  FIG. 1  showing the side fences in the stowed position. 
           [0009]      FIG. 2   a  is a detail perspective view of the side fences of the manual access ramp assembly of  FIG. 1  showing the side fences in the deployed position. 
           [0010]      FIG. 3  is a perspective view of an anti-jam timing system of the manual access ramp assembly of  FIG. 1 . 
           [0011]      FIG. 4  is a first detail perspective view of the anti-jam timing system of  FIG. 3 . 
           [0012]      FIG. 5  is a second detail perspective view of the anti-jam timing system of  FIG. 3 . 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings. 
         [0014]    A manual access ramp assembly  20  is illustrated in  FIG. 1 . The ramp assembly  20  includes a frame assembly  24  and a platform assembly  28 . The frame assembly  24  includes a set of parallel left and right tracks  32 . A pair of cross members  36  brace the tracks  32  at an inboard end and an outboard end of the frame assembly  24 . In an alternative construction a cover is attached to an upper side of the left and right tracks  32  to provide a smooth surface and to inhibit users from tripping on the left and right tracks  32  and the cross members  36 . 
         [0015]    The frame assembly  24  can be coupled to a structure or vehicle (not shown) so that the platform assembly  28  can be stowed or deployed relative to the structure or vehicle. The platform assembly  28  is selectively lockable in the deployed or stowed position. In one construction, the ramp assembly  20  is provided with a vehicle which may be a van or bus among other types. In such a construction, the frame assembly  24  may be coupled to at least one of a frame and a body of the vehicle at a location directly under the vehicle door to which ramp access is desired to aid entry to and exit from a side door of the vehicle. 
         [0016]    The platform assembly  28  includes a ramp platform  40  and a pair of left and right side fences  44 . The side fences  44  are movable between stowed and deployed positions, with the deployed position shown in phantom in  FIG. 1 .  FIG. 2  shows the side fences  44  in the stowed position and  FIG. 2   a  shows the side fences  44  in the deployed position. In the stowed position, each of the side fences  44  lies on the platform  40  so that the platform assembly  28  obtains maximum compactness for stowage. In the deployed position, each of the side fences  44  is at a substantially 90 degree angle with the platform  40 . In the deployed position, the side fences  44  keep feet, wheelchair wheels, etc. from slipping off the side edges of the platform  40 . The side fences  44  are selectively lockable in the deployed or deployed position. 
         [0017]    As shown in  FIGS. 1 and 2 , each of the side fences  44  is provided with an integrated pull handle  46  at an outboard end thereof. Each pull handle  46  includes an area of enlarged width and an aperture  46 A formed therein. In some constructions, each side fence  44  is constructed of a single piece of material formed with the enlarged area and the handle aperture  46 A. The platform  40  is provided with apertures  40 A corresponding to the apertures  46 A of the side fences  44 . When the side fences  44  are stowed, lying flat atop the platform  40 , the apertures  46 A of the side fences  44  lie directly above the apertures  46 A, effectively creating one pair of apertures in the platform assembly  28  that can be grasped by the two hands of a user to manipulate the platform assembly  28  when the side fences  44  are stowed. When the side fences  44  are in the deployed position, the integral pull handles  46  provide a convenient location for a user to grasp and manipulate the platform assembly  28 . The integral pull handles  46  also provide a convenient location for a user to grasp the side fences  44  during movement of the side fences  44  between the stowed and deployed positions. 
         [0018]    The entire platform assembly  28  is movable between a stowed position (not shown) and a deployed position ( FIG. 1 ). When in the stowed position, left and right side edges  48  of the platform assembly  28  are retained by the tracks  32  of the frame assembly  24 . The platform assembly  28  can be pulled substantially straight outward from the tracks  32  until the side edges  48  are free of the tracks  32  (i.e., obtaining the deployed position). Once deployed from the tracks  32 , the platform assembly  28  can be rotated relative to the frame assembly  24  and the tracks  32  about a substantially horizontal axis A as shown in  FIG. 1 . The platform assembly  28  is rotated about the axis A until an outboard edge  52  of the platform  40  contacts a desired surface, which may be at a significantly lower elevation than the elevation of the frame assembly  24 . An inboard edge  56  of the platform  40  is supported at the outboard cross member  36  of the frame assembly  24  ( FIGS. 3 and 4 ). 
         [0019]    As shown in  FIGS. 3-5 , an anti-jam timing system  60  couples the frame assembly  24  and the platform assembly  28 . The timing system  60  includes a cross shaft  64  that runs between the left and right tracks  32  at an angle substantially perpendicular to the tracks  32 . A sprocket or gear wheel  68  is provided on and coupled to each end of the cross shaft  64 . A pair of guide wheels  72  are positioned adjacent each of the gear wheels  68 . A toothed timing belt  76  is provided on each side of the ramp assembly  20  and serpentines around the corresponding guide wheels  72  and gear wheels  68  such that the teeth of each timing belt  76  engage with the corresponding gear wheel  68 . The guide wheels  72  may be toothed or un-toothed. The gear wheel  68 , the guide wheels  72 , and the timing belt  76  of each side are all housed substantially inside an open interior side of the corresponding one of the tracks  32 , which are substantially C-shaped. As best shown in  FIG. 4 , a clamp  80  is provided adjacent the outboard end of each of the tracks  32  to clamp and hold a free end of the corresponding timing belt  76 . The two clamps  80  are each coupled to the platform  40 . In one construction the two clamps  80  are coupled to the inboard edge  56  of the platform  40 . The two timing belts  76  are provided with substantially identical tooth spacing and the gear wheels  68  are substantially identical in diameter, tooth pitch, etc. so that the two gear wheels  68  rotate the same amount for a given length of timing belt  76  fed therethrough. 
         [0020]    As the platform assembly  28  is moved between the stowed and deployed positions (i.e., into and out of the tracks  32 ), the timing belts  76  on the two sides of the ramp assembly  20  are run through the corresponding gear wheel  68  and guide wheels  72  so that the left and right side edges  48  of the platform assembly  28  are kept in even time with each other. Thus, the platform assembly  28  is maintained substantially parallel with the two tracks  32  and binding, wedging, or jamming of the platform assembly  28  relative to the frame assembly  24  and specifically the tracks  32  is avoided. 
         [0021]    In an alternative embodiment an anti-jam timing system includes a non-toothed timing belt and a gear wheel with a substantially smooth circumference. The timing belt and gear wheel are sized and configured to provide a set amount of friction between the timing belt and the gear wheel to assist the left and right side edges  48  of the platform assembly  28  in keeping even time with each other. In yet another alternative embodiment the anti-jam timing system includes a pair of chains which function in a substantially similar fashion to the timing belts  76 . 
         [0022]    In yet another alternative embodiment each track  32  includes a substantially horizontal slot which runs approximately from one of the cross members  36  to the other cross member  36 . The guide wheels  72  are coupled to each track  32  using a bolt, screw, etc. such that the guide wheels  72  are free to move in the track  32  along the horizontal slot between the pair of cross members  36 . The bolt, screw, etc. inhibits each guide wheel  72  from being removed from the tracks  32 . In yet another embodiment the cross shaft  64  is coupled to each track  32  using a bolt, screw, etc. that passes through the horizontal slot on each track  32 . 
         [0023]    It should be understood that the embodiments described above and illustrated in the figures are presented by way of example only and are not intended as a limitation upon the concepts and principles of the present invention. As such, it will be appreciated by one having ordinary skill in the art that various changes are possible.