Abstract:
A detachable wheel system for a loading ramp is provided. The system comprises wheels which are easily attached for moving the ramp and detached from the ramp for storage. Also, the ramp surface can be provided with a serrated surface for additional grip for users of the ramp.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. provisional patent application No. 61/183,043, filed on Jun. 1, 2009. U.S. 61/183,043 was pending as of the filing date of this application. U.S. 61/183,043 is hereby incorporated by reference as if set forth in its entirety herein. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a set of detachable wheels for a loading ramp and a method of utilizing the wheels. More particularly, the present invention includes a pair of wheels which can be easily connected to and detached from a loading ramp, and then stowed for later use. The invention further relates to an improved ramp surface. 
         [0004]    2. Summary of Related Art 
         [0005]    Loading ramps for vehicles are commonly used to facilitate moving, loading, and transporting a wide variety of items from one elevation to another, particularly from the interior of the vehicle to the ground. Of particular interest, vehicle loading ramps are known and used to load and unload materials from commercial trucks. 
         [0006]    These loading ramps are commonly made of metal grating extending between side rails. The grating can be solid, or can consist of a series of individual segments. The ramps commonly include connecting mechanisms to connect the ramps to the vehicle. Typical, these connecting mechanisms comprise at least one hook end or ends designed to fit into and lock in with corresponding receiving notches on the floor of the vehicle at or near the vehicle door. 
         [0007]    Generally, the ramps are designed in such a manner as to be stowed underneath the vehicle. Usually structure is provided underneath the vehicle wherein the ramp can be retracted and stowed when the ramp is not in use. When it is time to use the ramp, it can be manually slid from the stowage mechanism and secured to the vehicle for loading or unloading. Upon completion of the use, the ramp is returned to its storage place for transport. 
         [0008]    In the case of larger vehicles, it is not uncommon to provide multiple doors for loading and unloading cargo. Typically one cargo door will be at the rear of the vehicle, and one or more cargo doors will be provided in the sides of the vehicle. In this case, it is not uncommon for one ramp to be provided and for the ramp to be totally removable from the vehicle. This ramp can then be moved to any of the vehicle cargo doors for loading and unloading. Due to the length of the ramp, it is generally stored along the length of the vehicle. 
         [0009]    One drawback of this system is that the ramp is typically manually transported from the rear of the vehicle to the side cargo doors. This can be difficult, due to the weight of the ramp and the significant length of the ramp, making it awkward to move. Additionally, with the weight and awkwardness of the ramp, there can be safety hazards to the person transporting the ramp. While the addition of wheels to the ramp may alleviate some of the difficulties of moving the ramp from one cargo door to another, this introduces additional difficulties for stowage of the ramp when not in use. 
       SUMMARY OF THE INVENTION 
       [0010]    According to the present invention, there is provided a set of detachable wheels for a cargo ramp. The wheels are designed in such a manner as to be easily attachable to, and detachable from, the loading ramp. In a preferred embodiment, a single pair of wheels is provided for a loading ramp, so as to create a fulcrum for pivoting the ramp. In another preferred embodiment the ramp includes a “serrated” surface for improved grip on the ramp. In other embodiments of the present invention an additional pair or pairs of wheels can be added. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    The above, as well as other advantages of the present invention, will become readily apparent to those skilled in the art from the following detailed description of a preferred embodiment when considered in the light of the accompanying drawings in which: 
           [0012]      FIG. 1  shows a view of a ramp according to the present invention; 
           [0013]      FIG. 2  shows a view of a wheel assembly connected to a ramp according to the present invention; 
           [0014]      FIG. 3  shows a view of a wheel assembly connecting to a ramp according to the present invention; 
           [0015]      FIG. 4  shows a view of a longitudinal beam according to the present invention; and 
           [0016]      FIG. 5  shows another view of a longitudinal beam according to the present invention. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0017]    In a preferred embodiment of the present invention, the ramp comprises a grated structure, with a pair of lengthwise or longitudinal primary beams connected by a series of cross struts. This type of ramp structure is customary in the art and can be of any conventional type. 
         [0018]      FIG. 1  shows a view of a ramp according to the present invention. The wheel assemblies  10 , for use with the ramp  12 , each comprise a wheel  14  and a leg  16 . The wheel  14  can be connected to the  16  leg by conventional mounting means  8 . The wheels  14  are preferably standard commercial wheels and are well known in the art. The length of the leg  16  can be chosen based on the dimensions of the ramp  12 , for ease of moving the ramp. As can be noted on  FIG. 2 , the wheel assembly also comprises a connecting piece  20 , connected to the leg, wherein the connecting piece  20  is designed to connect to the primary beam  22  of the ramp  12 . At least one hole  24  (see  FIG. 3 ) for a connecting pin  26  is provided in the connecting piece  20 , for connecting the wheel assembly  10  to the ramp  12 . The connecting piece  20  can be contiguous with or a separately connected piece from the leg  16 . 
         [0019]    The longitudinal primary beams  22  are each preferably designed with structure to receive the connecting piece of the wheel assembly. As shown in  FIG. 4 , the longitudinal beam is preferably designed with a U-shaped cross section  28 , with the connecting piece  20  designed to fit into the “U”. Additionally, the longitudinal beam  22  is preferably designed with a locking plate  30 , wherein the locking plate  30  connects the arms of the “U”, and is positioned so that a space is provided between the locking plate and the base of the “U”, thereby forming a slot  32  to receive the connecting piece of the wheel assembly. The connecting piece can be connected to the longitudinal beam with rivet, bolt, welding or other standard assembly techniques. There is also preferably provided in the longitudinal beam  22  a hole  34  (see  FIG. 5 ) for receiving a locking bolt or pin  26 . 
         [0020]    In order to secure the wheel structure to the longitudinal beam, a locking pin  26  is provided, which pin is designed to align through the hole  34  in the longitudinal beam  22  and the hole  24  in the connecting piece  20  of the wheel assembly  10  to secure them together. 
         [0021]    The invention is designed to utilize a pair of wheel assemblies, with one wheel assembly in each of the longitudinal beams of the ramp. Alternatively, multiple pairs of wheel assemblies can be utilized. 
         [0022]    When the ramp is stored on the vehicle the wheel assemblies are preferable disconnected and stored in the truck. Preferably, a mount can be provided on the truck for storing these assemblies, but it is not required. In an especially preferred embodiment of the present invention, the pins which are used to connect the wheel assemblies to the longitudinal beams are also used to secure the wheel assemblies to the mount. 
         [0023]    In order to move the ramp, the wheel assemblies  10  are removed from storage and connected to the ramp  12 . The connecting piece  20  is slotted into the U-shaped area and is slid under the mounting plate. The bolt  26  is then inserted through the holes  24 ,  34  in the wheel assembly and the ramp to secure them together. This is preferably done while the ramp is attached to the vehicle. Preferably, the legs of the wheel assemblies are of such a length that they do not touch the ground while the ramp is connected to the vehicle. After connecting the wheels, the ramp can be disconnected from the vehicle, and lowed to where the wheels make contact with the ground. The ramp and then be moved to its new desired position, and the ramp can then be re-secured to the vehicle. As the wheel assemblies are preferably designed so as not to interfere with loading and unloading operations involving the ramp, they can be left on the ramp while the ramp is in use, and only later be removed for storage. 
         [0024]    After usage of the ramp is completed, the wheel assemblies can be removed and stored, and the ramp returned to its stowage position under the truck. 
         [0025]    Thus, through the present invention, the ease for the operator of moving the ramp is increased, and unnecessary wear on the ramp can be avoided. Also, the provision of the wheels for the ramp can increase the safety of the ramp, as moving the ramp can be cumbersome and unsafe with ramps known in the field. 
         [0026]    In a preferred embodiment of a ramp  12  in accordance with the present invention, the longitudinal beams  22  of the ramp can be connected by a series of cross bracers  36 . Alternatively, a solid surface can be used to connect the sides  12  of the ramp. In order to improve traction, the ramp  12  can be provided with a serrated surface  38  for additional traction on the ramp. Known ramp surfaces can be very slippery, and subject users to unsafe conditions. In an effort to increase the safety of the ramp, the upper surface of the cross bracers can be serrated in order to increase traction by a user. This improved surface is shown in the attached figures. Preferably, each of the cross braces and have a surface with two or more protruding edges, and a recessed area therebetween. Each of the protruding edges can have a serrated or “toothed” surface, to increase the traction of the surface.