Abstract:
A method and apparatus for permitting construction equipment, and particularly backhoe loaders, to be transported in the hold of a seagoing vessel within the interior of an enclosed cargo container includes front and rear rollers that temporarily replace the wheels of the equipment and allow it to be driven into and out of the container without any disassembly of the equipment.

Description:
RELATED APPLICATIONS 
       [0001]    This application is a divisional application of U.S. patent application Ser. No. 12/268,463 filed Nov. 11, 2008. U.S. application Ser. No. 12/268,463 is expressly incorporated herein by reference in its entirety to form part of the present disclosure. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to the transport of construction equipment, and, more particularly, to a method and apparatus for permitting construction equipment to be driven into and out of enclosed cargo containers for transport in the hold of seagoing vessels. 
       BACKGROUND OF THE INVENTION 
       [0003]    The most common way of transporting construction equipment from the manufacturer to customers located in countries on other continents is by seagoing vessel. Typically, backhoe loaders and similar pieces of equipment are driven into the vessel hold and arranged as close together as practicable so as not to cause damage during loading, unloading or transport. In some instances, open top containers are employed which receive one or more pieces of equipment and are then loaded into the hold of the vessel. 
         [0004]    Charges for the transport of items by vessel are based on weight, or on the volume of the hold of the vessel that such items occupy. The hold volume is determined by the surface area of the floor of the hold and its overall height. The problem with shipping backhoe loaders and similar pieces of equipment is that while they may be arranged in close proximity to one another along the floor of the vessel hold, all of the volume of the hold above them is wasted space. Since vessel owners usually charge according to what generates the most revenue, manufacturers of construction equipment normally must pay according to the total volume of the hold located above their equipment even though it occupies space along only the floor area. 
         [0005]    Enclosed cargo containers have been employed for some time as a means of efficiently utilizing the total volume within the holds of vessels. Containers of this type may be stacked on top of one another and therefore fill much more of the total volume of the hold compared to items which cannot be stacked, such as construction equipment. While it would be advantageous to transport construction equipment within enclosed cargo containers, their dimensions are such that under current practices backhoe loaders and similar equipment do not fit therein without disassembly of at least a part of such equipment. 
       SUMMARY OF THE INVENTION 
       [0006]    This invention is directed to a method and apparatus for permitting construction equipment, and particularly backhoe loaders, to he transported in the hold of a seagoing vessel within the interior of an enclosed cargo container. 
         [0007]    In the presently preferred embodiment, a pair of front rollers and a pair of rear rollers are each formed from a first plate and a second plate that are welded together. Each plate has a flange which extends outwardly such that the flange of one plate opposes the flange of the other. A circumferentially extending outer ring is mounted to the flanges of the two plates, and a recess is formed in the outer ring within which an insert is secured. 
         [0008]    The front rollers and rear rollers are sized to temporarily take the place of the respective front and rear wheels of the backhoe loader such that its overall height dimension is reduced enough to allow it to be driven into and out of the interior of an enclosed cargo container. As discussed in detail below, the method of this invention allows a single worker to perform the loading and unloading operation without special tools and in an efficient manner. 
         [0009]    Use of enclosed cargo containers to ship backhoe loaders and similar equipment via seagoing vessels can result in a dramatic decrease in shipping costs. Because enclosed cargo containers can be stacked one on top of the other, much more of the volume of the vessel hold can be utilized with the method and apparatus of this invention compared to current practices, where, as discussed above, the equipment is merely driven into the vessel hold and all the space above the floor area is wasted. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    The structure, operation and advantages of the presently preferred embodiment of this invention will become further apparent upon consideration of the following description, taken in conjunction with the accompanying drawings, wherein: 
           [0011]      FIG. 1  is perspective view of a roller of this invention; 
           [0012]      FIG. 2  is a cross sectional view of a portion of the roller shown in  FIG. 1 ; 
           [0013]      FIG. 3  is a side view of a backhoe loader; 
           [0014]      FIG. 4  is a view similar to  FIG. 3 , except with the loader and rear stabilizer arms of a backhoe loader in the extended position; 
           [0015]      FIG. 5  is a view similar to  FIG. 4  showing the front and rear wheels removed and replaced by the rollers of this invention; and 
           [0016]      FIG. 6  is a view of backhoe loaders with the rollers mounted thereon driven into the interior of an enclosed cargo container. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0017]    Referring now to the Figs., the method and apparatus of this invention is illustrated with particular reference to a backhoe loader  10  which comprises a tractor  11 , a front loader  12  mounted to the front of the tractor  11  and a rear backhoe  14  mounted to the rear of the tractor  11 . The tractor  11  of the backhoe loader  10  further includes a cab  16 , a frame  18 , rear stabilizer arms  20  mounted on opposite sides of the frame  18 , front wheels  22  and rear wheels  24 . 
         [0018]    As best seen in  FIGS. 1 ,  2  and  5 , the apparatus of this invention comprises two front rollers  30  and two rear rollers  32 , only one of each of which is shown in the Figs. Each roller  30  and  32  has the same construction, except for its diameter, and therefore only the details of rear rollers  32  are described herein it being understood that the following discussion applies equally to the front rollers  30 . Each rear roller  32  comprises a first plate  34 , a second plate  36 , an outer ring  38  and an insert  40 . The first and second plates  34 ,  36  are generally circular in shape, and are essentially mirror images of one another. The first plate  34  has a center section  42  formed with a central bore  44  and a number of wheel stud holes  46  that extend radially outwardly from, and are circumferentially spaced about, the central bore  44 . The outer portion of the first plate  34  is bent to form a flange  48  that is oriented substantially perpendicularly to the center section  42  of the first plate  34 . The second plate  36  has the same construction as first plate  34 . it includes a center section  50  having a central bore  52 , wheel stud holes  54  and a flange  56 . The first and second plates  34 ,  36  are oriented relative to one another so that their center sections  42 ,  50  abut, the respective central bores  44 ,  52  and wheel stud holes  46 ,  54  align, and, the flanges  48 ,  56  are located opposite one another in substantially the same plane. In this position, the first and second plates  34 ,  36  are preferably welded to one another, such as by a series of circumferentially spaced welds  58 , one of which is shown in  FIG. 2 . 
         [0019]    The outer ring  38  rests against the flange  48  of the first plate  34  and against the flange  56  of the second plate  36 . An outer portion  60  of the outer ring  38  extends radially outwardly from an outer edge  64  of the flange  48 , and an outer portion  62  of the outer ring  38  extends radially outwardly from an outer edge  66  of the flange  56 . The outer portions  60 ,  62  of outer ring  38  provide a surface for welding in order to connect the outer ring  38  to the flanges  48 ,  56 , such as by welds  68 , as illustrated in  FIGS. 1 and 2 . The outer ring  38  is also formed with a circumferential recess  70  within which the insert  40  is mounted. In the presently preferred embodiment, the edges  72  and  74  on opposite sides of the outer ring  38  are each formed with a taper. This allows a milling machine (not shown) to form a convex curvature on the exposed surface  76  of the insert  40  without interference from the outer ring  38 . See  FIG. 2 . 
         [0020]    The method of this invention may be described with reference to  FIGS. 3-6 . The backhoe loader  10  is initially depicted in a position with the rear stabilizer arms  20  of the tractor  11  extended but off of the ground  76 . See  FIG. 3 , The front loader  12  and stabilizer arms  20  are then both extended, as shown in  FIG. 4 , so that the frame  18 , front wheels  22  and rear wheels  24  of the tractor  11  are lifted off of the ground. For purposes of the present discussion, the term “wheel” as used herein refers to both the wheels and tires of the tractor  11  of the backhoe loader  10 . With the backhoe loader  10  in the position shown in  FIG. 4 , a worker may loosen the wheel lugs (not shown) holding the front and rear wheels  22 ,  24  of the tractor  11  on the wheel studs (not shown) and then remove all four wheels  22 ,  24 . 
         [0021]    The method of this invention may be described with reference to  FIGS. 3-6 . The backhoe loader  10  is initially depicted in a position with the rear stabilizer arms  20  of the tractor  11  extended but off of the ground  76 . See  FIG. 3 . The front loader  12  and stabilizer arms  20  are then both extended, as shown in  FIG. 4 , so that the frame  18 , front wheels  22  and rear wheels  24  of the tractor  11  are lifted off of the ground. For purposes of the present discussion, the term “wheel” as used herein refers to both the wheels and tires of the tractor  11  of the backhoe loader  10 . With the backhoe loader  10  in the position shown in  FIG. 4 , a worker may loosen the wheel lugs (not shown) holding the front and rear wheels  22 ,  24  of the tractor  11  on the wheel studs (not shown) and then remove all four wheels  22 ,  24 . 
         [0022]    Referring to  FIG. 5 , the front wheels  22  of the tractor  11  are replaced with two front rollers  30  of this invention, and the rear wheels  24  of the tractor  11  are replaced by two rear rollers  32 . As noted above and seen in  FIG. 5 , the front rollers  30  have the same construction as the rear rollers, except a smaller diameter just as the front wheels  22  of the backhoe loader  10  are smaller than its rear wheels  24 . After the front and rear rollers  30 ,  32  are in place, the loader  12  and stabilizer arms  20  may be retracted so that the weight of the backhoe loader  10  is now carried by such rollers  30 ,  32 . The diameters of the rollers  30 ,  32  are chosen so that the overall height of the backhoe loader  10 , e.g. the dimension from the lowermost portion of the frame  18  to the top of the cab  16  of the tractor  11  is less than the height of the enclosed cargo container  28 . Consequently, the backhoe loader  10  may be driven into the enclosed cargo container  28  without interference from the top or bottom walls of the container  28 . The insert  40  undergoes limited, if any, compression under the weight of the backhoe loader  10  to ensure that the frame  18  does not engage the ground or bottom wall of the enclosed container  28 . Additionally, the convexly curved exposed surface  76  of the insert  40  resists tearing or other damage due to shear forces generated by turning of the rollers  30 ,  32  along the ground or bottom of the container  28  as the backhoe loader  10  is driven into and out of the container  28 . If desired, the wheels  22 ,  24  of the tractor  11  of the backhoe loader  10  may be inserted into the container  28  in the areas between adjacent backhoe loaders  10  (not shown) to fill up that space and provide a convenient means of transporting the wheels  22 ,  24 . 
         [0023]    When the vessel carrying the cargo container  28  reaches its destination, the procedure described above is simply reversed. Each backhoe loader  10  may be driven out of the container  28 , and the rollers  30 ,  32  replaced with wheels  22 ,  24  of the tractor  11  by raising and lowering the frame  18  as discussed above. The transport of backhoe loaders  10  and similar types of construction equipment by the method of this invention greatly reduces shipping costs by allowing stackable, enclosed cargo containers  28  to be employed which more efficiently use the total volume of the hold of shipping vessels than existing methods of transport. 
         [0024]    While the invention has been described with reference to a preferred embodiment, it should be understood by those skilled in the art that various changes may be made and equivalents substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.