Abstract:
The tri-folding ramp is a portable, collapsible device that includes three sections which define an upper surface of the ramp as having an arc-shaped profile. The arc-shaped profile of the ramp can reduce the loading angle between the distal end of the ramp and an upper loading surface, thereby inhibiting contact between the vehicle&#39;s undercarriage and the ramp&#39;s upper surface and/or the upper loading surface as the vehicle is entering or exiting the ramp.

Description:
BACKGROUND  
       [0001]     The present invention is drawn to a tri-folding ramp for loading a vehicle or the like onto a loading surface. The tri-folding ramp comprises a plurality of sections which form a loading member. The loading member has an upper support surface which assumes an arc-shaped profile when the ramp is in an extended configuration. The arced profile deters contact between the ramp or loading surface and the undercarriage of a vehicle as the vehicle travels over the ramp and is loaded onto such loading surface. Furthermore, the tri-folding ramp is lightweight and collapsible into a collapsed configuration for storage and transport.  
         [0002]     It is often desirable to haul a vehicle from one location to another. By placing the vehicle on the loading surface of a trailer or truck, the vehicle can be easily transported to the desired location and then unloaded for use. Lightweight vehicles can typically be lifted or lowered by hand onto the loading surface, but heavier vehicles such as lawnmowers, all terrain vehicles (ATVs), automobiles, trucks and motorcycles typically require other means to facilitate loading.  
         [0003]     Ramps are commonly used for loading by providing a continuous span from one loading surface to another in order to facilitate loading and unloading various devices. A ramp is especially useful when moving a heavy device between two loading surfaces that are disposed at different heights. Typically the ramp is positioned with a first end resting on a lower surface and a second end resting on an upper surface. The device is then simply driven or pushed from the first loading surface, across the ramp and onto the second loading surface. However, one of the problems associated with using a ramp is the size of the loading angle that is created between the end of the ramp and the upper loading surface. A large loading angle can cause a vehicle, especially one with a low undercarriage to bottom out during loading or unloading. As the vehicle moves between the ramp and the loading surface, the vehicle&#39;s undercarriage can scrape the ramp or loading surface at or near the juncture of the ramp and loading surface. This can result in damage to the vehicle, the ramp, the loading surface or all three. Such damage can be costly and time-consuming to repair.  
         [0004]     The loading angle between the end of the ramp and an upper loading surface can be reduced to avoid problems of scraping the vehicle&#39;s undercarriage. By increasing the length of the ramp, the sharpness of the angle between the ramp and upper loading surface is decreased. However, by increasing the ramp&#39;s length, the strength of the ramp is weakened, thereby decreasing its load-bearing ability. Furthermore, the weight and bulk of the ramp is increased, making the ramp more difficult to transport and install.  
         [0005]     There is a need for a ramp that creates a low loading angle with the upper loading surface in order to deter contact between the undercarriage of the vehicle and the ramp or loading surface during the loading and unloading process. There is an additional need for a ramp that is lightweight, yet strong enough to support a heavy vehicle, such as a lawnmower, an ATV, a motorcycle, a car or a truck. In addition, a need exists for a ramp that is easy to store, transport and install.  
       SUMMARY  
       [0006]     The present invention is drawn to a tri-folding ramp comprising three sections that are pivotally attached. The ramp, used for loading, includes a collapsed configuration and an extended configuration. In the extended configuration, the upper surface of the ramp comprises an arced profile. The tri-folding ramp further comprises means for supporting the ramp on a loading surface. Means for securing a loading member to a fixed support in order to maintain the loading member between first and second loading surfaces is also comprised by the ramp.  
         [0007]     It is an object of the present invention to provide a ramp that can be extended for use and collapsed into a compact form for storage or transport.  
         [0008]     It is a further object of the present invention to provide a ramp for loading of vehicles wherein the ramp deters scraping of the vehicle&#39;s undercarriage on the ramp or loading surface during loading and unloading.  
         [0009]     It is a further object of the present invention to provide a tri-folding ramp that has an upper surface with an arced profile.  
         [0010]     It is a further object of the present invention to provide a ramp which creates a small loading angle between the upper end of the ramp and the upper loading surface.  
         [0011]     It is a further object of the present invention to provide a ramp comprising three independently pivotable sections that can be folded from an extended configuration into a collapsed configuration which is approximately one third of the length of its extended configuration.  
         [0012]     Loading ramps facilitate moving a vehicle or other equipment from one loading surface to another loading surface. One loading surface can be located higher than the other loading surface. The ramp of the present invention is an elongated loading member with an upper surface which provides a pathway on which the vehicle is moved from one loading surface to another. To install, one end of the ramp is usually propped on the lower loading surface while the other end engages the upper loading surface. The loading angle between the upper loading surface and the ramp is a function of the ramp&#39;s length given a fixed height between the loading surfaces. The shorter the ramp, the sharper or greater the angle between the ramp and the upper loading surface. With a sharper loading angle, the vehicle will have a tendency to bottom out as it passes over the juncture between the ramp and upper loading surface. This can damage the vehicle, the ramp and/or the upper loading surface. In some instances such contact can force the ramp to pull away from the upper loading surface and fall to the ground, possible damaging the vehicle.  
         [0013]     By providing an arced profile to the upper surface of the tri-folding ramp, the loading angle between the ramp and the upper loading surface is decreased without increasing the length of the ramp. Each of the three sections when the ramp is extended are disposed at an obtuse angle to the adjoining section (s), thereby creating an upper surface on the ramp that is not planar and each of the three sections extend in different planes. This arrangement decreases the loading angle between the ramp and the upper loading surface when the ramp is installed to thereby inhibit a vehicle from bottoming out when moving between the ramp and the loading surface.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]      FIG. 1  is a perspective view of an embodiment of the tri-folding ramp of the present invention in the extended configuration.  
         [0015]      FIG. 2  is an exploded view of the tri-folding ramp of  FIG. 1 .  
         [0016]      FIG. 3  is a side view of the tri-folding ramp of  FIG. 1  in the extended configuration and positioned on an upper loading surface.  
         [0017]      FIG. 4  is an exploded view of one of the hinges of the invention of  FIG. 1 .  
         [0018]      FIG. 5  is a perspective view of the tri-folding ramp of  FIG. 1  in a collapsed configuration.  
         [0019]      FIG. 6  is a side view of the hinge of  FIG. 4 .  
         [0020]      FIG. 7  is a side view of a second embodiment of the tri-folding ramp of the present invention in the extended configuration. The angle formed by the top surfaces of the middle section and the first end section is less than the angle formed by the top surfaces of the middle section and the second end section.  
         [0021]      FIG. 8  is a side view of a third embodiment of the tri-folding ramp of the present invention in the extended configuration and positioned on an upper loading surface, wherein the angle formed by the top surfaces of the first end section and the middle section is greater than the angle formed by the top surfaces of the second end section and the middle section. 
     
    
     DETAILED DESCRIPTION  
       [0022]     A preferred embodiment of the tri-folding ramp  1  of the present invention as shown in  FIGS. 1-3  is adapted to extend between two loading surfaces. The two loading surfaces can be the same height or different heights. When using examples where the loading surfaces are positioned at different heights, reference is made herein to an upper loading surface  100  and a lower loading surface  200 .  
         [0023]     The ramp  1  comprises a loading member  2  and means for supporting the ramp. The loading member  2  comprises a plurality of sections  3 . The sections  3  include a middle section  4 , a first  5  and a second  6  end sections and means for attaching the sections. The ramp  1  also includes means for securing the loading member to a fixed support.  
         [0024]     The first end section  5  includes a top surface  7 . Likewise, the second end section  6  and the middle section  4  have respective top surfaces  7 . The top surfaces  7  define a somewhat continuous upper surface  28  when the ramp  1  is in an extended configuration.  
         [0025]     The means for attaching the sections comprises a plurality of hinges  8 . The plurality of hinges  8  include first  9 , second  10 , third  11  and fourth  12  hinges. The first  9  and second  10  hinges are disposed between the first end section  5  and the middle section  4 . The third  11  and fourth  12  hinges are disposed between the second end section  6  and the middle section  4 . The first  9 , second  10 , third  11  and fourth  12  hinges generally comprise the same structure. The following description of the first hinge  9  is descriptive of each of the other second  10 , third  11  and fourth  12  hinges.  
         [0026]     Referring to  FIG. 4 , the hinge  9  comprises a first portion  13  and a second portion  14 . Each of the first  13  and second  14  portions includes a stile engaging bracket  15 , a limit stop  16 , and a pivotal attachment portion  17 . Stile engaging bracket  15  of each portion  13 , 14  is formed by a top wall  18  and two side walls  19 . The pivotal attachment portion  17  of each portion  13 , 14  includes a pair of tabs  20 . Each of the tabs  20  extends from a bottom edge of a respective side wall  19  of the stile engaging bracket  15 . Each limit stop  16  includes first  21  and second  22  faces.  
         [0027]     Means for supporting the ramp comprises a support bracket  23  as shown in  FIGS. 1 and 2 . The support bracket  23  is a pair of elongated curved members  24 . The curved members  24  are adapted to rest on one of the loading surfaces when the ramp  1  is in use.  
         [0028]     The means for securing the loading member to a fixed support is an adjustable strap  25 . In a preferred embodiment, the adjustable strap  25  has a loop  26  at one end and a hook  27  disposed on the opposite end of the strap  25 . Means for adjusting is disposed on the strap  25 . The means for adjusting comprises a spring clip which enables the effective length of the strap  25  to be varied.  
         [0029]     The first  13  and second  14  portions on each hinge  9 , 10 , 11 , 12  are generally U-shaped with the top wall  18  being flanked by the side walls  19 . Each of the elongated curved members  24  have a rectangular cross section and a slight V-shaped side profile.  
         [0030]     Preferably, the loading member  2  is made of aluminum which provides the ramp  1  with high strength and lightweight characteristics. Although the preferred embodiment is disclosed to comprise aluminum, other suitable materials including high strength plastics, wood, composites, and other metals could be used instead.  
         [0031]     In a preferred use, the loading member  2  extends between the lower loading surface  200  and the upper loading surface  100 . The upper surface  28  of the ramp  1  directly supports the vehicle as it moves across the ramp  1  from one loading surface to the other.  
         [0032]     The hinges  8  pivotally attach the sections  3  together in a series. The limit stops  16  limit the outward pivoting of the sections  3 . When the ramp  1  is unfolded the limit stops  16  hold the top surfaces  7  of each of the sections  4 , 5 , 6  in relatively fixed positions at predetermined angles to each other. In the preferred embodiment of  FIG. 3 , the predetermined angle between the top surfaces  7  of the first end section  5  and the middle section  4  and the predetermined angle between the top surfaces  7  of the second end section  6  and the middle section are of substantially equal magnitude.  
         [0033]     Both of the first  5  and second  6  end sections are characterized by a distal end  29  and a proximal end  30 . The middle section  4  has a pair of attaching ends  31  disposed opposite from each other. The proximal end  30  of the first end section  5  is attached to one of the attaching ends  31  of the middle section  4  by the first  9  and second  10  hinges. The proximal end  30  of the second end section  6  is attached to an opposite attaching end  31  of the middle section  4  by the third  11  and fourth  12  hinges. In addition, the support bracket  23  is fixedly attached to the distal end  29  of the second end section  6 .  
         [0034]     The tabs  20  in  FIG. 4  are disposed on the first  13  and second  14  portions of each hinge  9 , 10 , 11 , 12 . The tabs  20  of the first portion  13  overlap the tabs  20  of the second portion  14 . The pivotal attachment portion  17  of each first  13  and second  14  portion further includes apertures  32  which extend through the overlapping tabs  20 . A pivot pin  33  extends through the apertures  32  of the tabs  20  on each hinge  9 , 10 , 11 , 12  and defines a pivot point thereby allowing pivotal movement between the first  13  and second  14  portions of the respective hinge  9 , 10 , 11 , 12 . That pivotal movement is imparted to the attached sections  4 , 5 , 6 .  
         [0035]     In a preferred embodiment shown in  FIGS. 1, 2  and  4 , the first end section  5  comprises a pair of stiles  34  and a plurality of transverse members  35 . The transverse members  35  extend between the stiles  34 . One side of the transverse members  35  define the top surface  7  of the first end section  5 . Similarly, the second end section  6  and middle section  4  are each formed by a pair of stiles  34  and transverse members  35 . One side of the transverse members  35  of the second end section  6  form the top surface  7  of the second end section  6  and one side of the transverse members  35  of the middle section  4  define the top surface  7  of the middle section  4 .  
         [0036]     The first end section  5  and middle section  4  are pivotally connected by the first  9  and second  10  hinges. The stile engaging brackets  15  of the first  9  and second  10  hinges are attached to respective stiles  34  of the first end section  5 . The stile engaging brackets  15  of the second portions  14  of the first  9  and second  10  hinges are attached to the respective stiles  34  of one of the attaching ends  31  of the middle section  4 .  
         [0037]     Similarly, the stile engaging brackets  15  of the respective first portion  13  of each of the third  11  and fourth  12  hinges is attached to the respective stiles  34  of the second end section  6 , while the stile engaging brackets  15  of the second portion  14  of each of the first  9  and second  10  hinges is attached to the respective stiles  34  of another of the attaching ends  6  of the middle section  4 .  
         [0038]     In a preferred embodiment, the top  18  and side  19  walls of each of the first  13  and second  14  portions partially surround the respective attached stile  34 . A pair of side bolts  36  extend through the side walls  19  and stile  34  to secure each hinge  9 , 10 , 11 , 12  onto the respective attached stile  34 . In addition, a single top bolt  37  extends through the top wall  18  of each stile engaging bracket  15  and the respective attached stile  34 . Although bolts are used to secure the stile engaging brackets  15  to the stiles  34 , other attachments including welds, rivets or adhesives could be used instead. Alternatively, the stile engaging brackets could be integral with the stiles.  
         [0039]     The respective first  21  and second  22  faces of each first  9 , second  10 , third  11  and fourth  12  hinge are adapted to abut each other when the ramp  1  is in the extended configuration. A load positioned on the upper surface  28  of the ramp  1  creates a downward force on the loading member  2  which presses the first  21  and second  22  faces of each of the hinges  9 , 10 , 11 , 12  toward each other and engages the limit stops  16 .  
         [0040]     When the first  21  and second  22  faces are abutting, the top surfaces  7  of two adjoined sections  4 , 5  and  5 , 6  are maintained at a predetermined angle as shown in  FIGS. 4 and 6 . The predetermined angle A 1 , A 2  between the top surfaces  4 , 5  and  5 , 6  of the two adjoined sections are obtuse. The magnitude of the predetermined angles A 1 , A 2  is a function of the limit stop  16  which is dictated by the angle at which the first  21  and second  22  faces of each of the hinges  9 , 10 , 11 , 12  abut one another relative to the top surface  7  of the respective section  4 , 5 , 6 .  
         [0041]     The included angle A 3  between the first face  21  and the top surface  7  of the first section  5  is an acute angle being less than 90 degrees. Likewise, an included angle A 3  between the second face  22  and the top surface  7  of the middle section  4  is less than 90 degrees.  
         [0042]     On the third  11  and fourth  12  hinges, the first  21  and second  22  faces of the respective first  13  and second  14  portions are formed at an acute angle to the respective top surfaces  7  of the second end section  6  and the middle section  4 .  
         [0043]     With the ramp  1  in the extended configuration, the top surfaces  7  of the sections  4 , 5 , 6  are not coplanar. In addition, the upper surface  28  of the loading member  2  is non-planar and comprises an arc-shaped profile.  
         [0044]     Although the predetermined angles in one preferred embodiment are approximately equal, the predetermined angles may be of different magnitudes. For example, in a second embodiment shown in  FIG. 7 , the predetermined angle formed between the top surfaces of the middle section  4  and the first end section  5  is smaller than the predetermined angle formed between the top surfaces of the middle section  4  and the second end section  6  when the ramp is fully extended. Alternatively, in a third embodiment shown in  FIG. 8 , the predetermined angle between the top surfaces of the first end section  7  and the middle section  4  is greater than the angle formed between the top surfaces  7  of the middle section  4  and the second end section  7  when the ramp is in the extended configuration.  
         [0045]     The pair of elongated curved members  24  are disposed on the distal end  29  of the second end section  6 . Each of the elongated curved members  24  is attached to a respective one of the stiles  34  of the second end section  6 . Both of the elongated curved members  24  have a free end  38  that extends outwardly beyond the second end section  6 . The free ends  38  are adapted to engage the upper loading surface  100  when the ramp  1  is installed.  
         [0046]     The adjustable strap  25  is looped around at least one of the transverse members  35  and secured to a fixed support, such as the upper loading surface  100  upon installation.  
         [0047]     Preferably, the first  5  and second  6  sections including the support bracket  23  are approximately the same length. The middle section  4  is at least as long or longer than either of the first  5  and second  6  end sections.  
         [0048]     The ramp  1  comprises a collapsed configuration and an extended configuration. The collapsed configuration as shown in  FIG. 5  is characterized by the first  5  and second  6  end sections being folded across the middle section  4 . In this configuration, the ramp  1  is in a compact form whereby the ramp&#39;s effective length is shorter than the length of the ramp when extended. The adjustable strap  25  can be looped around the folded sections  4 , 5 , 6  and secured to hold the ramp  1  in the collapsed configuration. Due to the compactness of the loading member  2  when folded, the ramp  1  can be more easily stored and transported.  
         [0049]     The extended configuration is shown in  FIGS. 1 and 3  in which the first  5  and second  6  end sections are folded out and away from the middle section  4 . In this configuration the limit stops  16  of the first  9  and second  10  hinges and the limit stops  16  of the third  11  and fourth  12  hinges are engaged. The first  21  and second  22  faces of the limit stop  16  on each pair of hinges  9 , 10  and  11 , 12  are proximate or abutting when the ramp  1  is in the extended configuration. The top surface  7  of the first end section  5  is disposed at an angle to the top surface  7  of the middle section  4 . Likewise, the top surface  7  of the second end section  6  is disposed at an angle to the top surface  7  of the middle section  4  such that the top surfaces  7  of the first  5  and second  6  end sections extend angularly away from the top surface  7  of the middle section  4 .  
         [0050]     The upper surface  28  of the loading member  2  has an arc-shaped profile. Consequently, the upper surface  28  formed by the top surfaces  7  of the first end section  5 , the middle section  4  and the second end section  6  is not planar when the ramp  1  is disposed in the extended configuration. The angle A 1  formed between the top surfaces  7  of the first end section  5  and the middle section  4  and the angle A 2  formed between the top surfaces  7  of the second end section  6  and the middle section  4  are predetermined and maintained by the limit stops  16  on the hinges  9 , 10 , 11 , 12 . Each of the first  21  and second  22  faces is disposed at an angle of less than 90 degrees relative to the top surface  7  of the respective section  4 , 5 , 6 .  
         [0051]     The first  21  and second  22  faces of each respective hinge  9 , 10 , 11 , 12  are proximate to and/or abutting each other when the ramp  1  is in the extended configuration. Conversely, when the ramp  1  is in the collapsed configuration, the first  21  and second  22  faces are spaced away from each other and are not abutting.  
         [0052]     The upper surface  28  of the ramp  1  is directly upwardly during use. The distal end  29  of the first end section  5  rests on the lower loading surface  200  while the elongated curved members  24  on the second end section  6  are engaged with the upper loading surface  100 .  
         [0053]     To install the tri-folding ramp  1  of the present invention, the loading member  2  is transformed from the collapsed configuration into the extended configuration and positioned to extend from the upper support surface  100  to the lower support surface  200 . The means for securing the loading member is engaged with a fixed support.  
         [0054]     To unfold the ramp  1  from the collapsed configuration to the extended configuration, the second end section  6  is pivoted outwardly and away from the underlying first end section  5  and middle section  4  until the first  21  and second  22  faces of the hinges  9 , 10 , 11 , 12  are proximate and/or abut each other. The first end section  5  is then pivoted outwardly and away from the middle section  4 , until the limit stop  16  of the first  9  and second  10  hinges deter further pivotal movement therebetween.  
         [0055]     With the ramp  1  in the extended configuration the support bracket  23  is placed on the upper loading surface  100  with the lower sides of the elongated curved members  24  resting on the upper loading surface  100 . The distal end  29  of the first end section  5  is placed on the lower loading surface  200 .  
         [0056]     The adjustable strap  25  is attached to at least one of the transverse members  35  and may be secured to a fixed support by looping the strap  25  around the fixed support and securing the hook  27  thereto, or by directly securing the hook  27  to the fixed support.  
         [0057]     The tri-folding ramp of the present invention is a strong, lightweight device used to assist in moving vehicles from one loading surface to another. In use, the ramp inhibits the vehicle from bottoming out or scraping its undercarriage as the vehicle is moved across the ramp and onto a loading surface or vice versa. In addition, the ramp can be folded from an in-use, extended configuration into a collapsed configuration that is convenient for storage. In the collapsed configuration, the ramp can be easily carried along with the transported vehicle to facilitate loading and unloading at different locations.  
         [0058]     Although the present invention has been described in considerable detail with reference to certain preferred versions thereof, other versions are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred versions contained herein.