Abstract:
A transport system for farm combines and other large wheel and track mounted equipment. A trailer for the equipment is constructed by a lightweight manner by providing its frame with narrowly spaced side rails separated by a distance less than the width of the equipment that is carried on the trailer. The axles of the transported equipment are each provided with detachable rollers that slide along the side rails as the equipment is pulled on and off of the trailer by a winch driven pulley and cable system. The narrow width of the trailer minimizes its weight so that the trailer can carry two combines at the same time without the weight exceeding highway weight regulations.

Description:
FIELD OF THE INVENTION 
     This invention relates generally to the transporting of large vehicles and more particularly to a trailer system for hauling farm combines and other large vehicles over the road. 
     BACKGROUND OF THE INVENTION 
     The harvesting of agricultural crops typically involves the use of large farm implements that are commonly known as combines. Combines are used to cut, thresh, and clean various types of grain. Combines are large and expensive machines that are often used in one field and then moved to other fields for work there. Because combines are extremely heavy and wide, the trailers that carry them between fields must be wide and heavy structures in order to be able to handle the size and weight of the combine. 
     While it is desirable for efficiency to be able to transport two combines on a single trailer, weight and size considerations make this generally impractical for modern combines. In order to be able to haul two combines at once, the trailer must be wide enough and long enough to handle the size of the combines. This, together with the structural requirements of the trailer, result in the trailer being unduly heavy. The trailer, together with two combines loaded on it, is thus too heavy to comply with highway regulations regarding weight limits. Consequently, it is common practice for combines to be carried between fields one at a time, each on its own trailer. This inefficiency adds to the cost and inconvenience involved in agricultural harvesting operations. 
     Other types of large equipment face similar problems. For example, bulldozers and other large earth moving and construction machinery are too large and heavy to be easily transported between job sites. Many types of vehicles, both track driven machines and wheeled machines, are subject to the same transportation difficulties. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a unique system for efficiently transporting large vehicles such as agricultural combines, bulldozers, and other heavy equipment. In accordance with the invention, a wheeled trailer has a relatively lightweight frame that includes a pair of parallel side rails. The side rails may take the form of I-beams, and they are spaced apart less than the width of the large machinery that the trailer is intended to carry. This allows the width of the trailer to be minimized which in turn reduces the overall weight of the trailer, a key feature of the invention. 
     Another important aspect of the invention involves equipping the axles of the vehicle that is to be transported with rollers or other friction reducing elements. These rollers or other elements are spaced apart such that they can ride along the side rails of the trailer while the implement is being loaded onto and off of the trailer. A cable and pulley system may be driven by a winch to pull the combine or other vehicle onto and off of the trailer. By providing rollers on the vehicle axles, the frame of the trailer can be considerably less than the width of the combine, with the combine overhanging both sides of the trailer. As a consequence, the frame of the trailer is reduced in size and weight so that it can simultaneously transport two combines, one behind the other, and still conform to prevailing highway weight limitations. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the accompanying drawings which form a part of the specification and are to be read in conjunction therewith and in which like reference numerals are used to indicate like parts in the various views: 
     FIG. 1 is a top plan view diagrammatically illustrating a trailer constructed in accordance with the present invention, with a farm combine that can be carried on the trailer partially shown in broken lines; 
     FIG. 2 is a side elevational view of the trailer shown in FIG. 1; 
     FIG. 3 is a fragmentary rear elevational view on an enlarged scale showing the side rails of the trailer and rollers that are mounted on the axle of the farm combine and roll along the side rails to facilitate loading and unloading of the combine; 
     FIG. 4 is a fragmentary rear elevational view showing a detachable mounting arrangement for securing one of the rollers detachably to the combine axle; 
     FIG. 5 is a side elevational view showing the detachable mounting of one of the rollers to the combine axle; 
     FIG. 6 is a side elevational view of a trailer that is equipped with a cable and pulley system in order to pull a farm combine or other large vehicle onto and off of the trailer in accordance with the present invention; and 
     FIG. 7 is a top plan view of the trailer shown in FIG.  6  and depicting details of the cable and pulley system, together with a winch that may be used to drive the cable and pulley system. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings in more detail and initially to FIG. 1, the present invention is directed to a trailer which is generally identified by numeral  10  and which is used to transport large vehicles such as a conventional farm combine which is partially shown in FIG.  1  and identified generally by numeral  12 . The combine  12  has a conventional construction and includes plural axles  14 , each of which carries a pair of wheels  16  on its opposite ends. 
     The trailer  10  has a rigid wheel mounted frame which includes as its principal structural components a pair of parallel side rails  18 . The side rails  18  form the opposite sides of the trailer frame and may take the form of I-beam. As best shown in FIG. 3, each of the side rails  18  may include an upper flange  20 , a lower flange  22 , and a vertical web  24  which connects the upper and lower flanges at their lateral centers. The trailer  10  preferably includes a pair of axles  26  (FIG. 1) which are suitably connected with the side rails  18 . Plural wheels  28  are mounted on the opposite ends of each of the axles  26 . The front portion  30  of the frame of the trailer  10  extends upwardly somewhat and is equipped with a front cross member  32  and a hitch  34  (FIG. 2) for connection with a suitable towing vehicle such as a truck (not shown). 
     For simplicity, the construction of the trailer  10  is shown diagrammatically. Suitable structural members which are not shown may be used to connect the two side rails  18  at selected intervals. However, it is noted that the trailer exhibits a narrow width in that the side rails  18  are spaced apart a distance less than the length of the axle  14 . Thus, the trailer is relatively narrow and also relatively lightweight because long cross members are not required due to the relatively short spacing between the side rails  18 . At the same time, the side rails  18  and the overall trailer frame are constructed in a manner to exhibit the strength necessary to transport the combine  12  along with a second combine, one behind the other on the trailer frame as will be described in more detail. 
     In accordance with the invention, each of the combine axles  14  is equipped with a pair of friction reducing elements that ride along the side rails  18  of the trailer frame as the combine is being loaded onto and off of the trailer  10 . With particular reference to FIG. 3, the friction reducing elements may take the form of flanged rollers  36 . Each roller  36  is mounted to turn on a shaft or axle  38  extending between a pair of lugs  40  which are suitably mounted to the axle  14  to project downwardly from its underside. The horizontal rollers  36  are spaced apart on the axle  14  to conform with the spacing between the two side rails  18 . In addition, each roller  36  is provided on its opposite ends with flanges  36   a  which are spaced apart a distance slightly greater than the width of each of the upper flanges  20 . Thus, as best shown in FIG. 3, the flanges  36   a  are located adjacent to the edges of the flanges  20  to provide a guiding function and maintain the rollers  36  on the side rails  18 . 
     While the rollers  36  or other friction reducing elements that are provided may be is permanently mounted on the axles  14 , it is generally preferable for the friction reducing elements to be detachably mounted to the combine axles  14  so that they can be removed when the combine is working in agricultural fields. FIGS. 4 and 5 show diagrammatically a system for detachably connecting the rollers  36  with the axles  14 . 
     As shown in FIGS. 4 and 5, the lugs  40  may be attached to brackets  42  which are fitted against the undersides of the axles  14 . Each bracket  42  has a pair of outwardly projecting lips  44  on its upper end. A pair of ratchet straps  46  may be provided for each of the brackets  42 , with the ratchet straps  46  being connected with the lugs  44  and being capable of being tightened around the top portion of the axle  14  in order to rigidly secure the bracket  42  in place on the axle. The ratchet straps  46  may be loosened and released so that the brackets  42  and rollers  36  can be removed from the axles  14  when not needed. 
     FIGS. 6 and 7 depict a cable and pulley system that may be provided for the trailer  10  (shown in FIGS. 6 and 7 in a slightly different front end configuration than in FIGS.  1  and  2 ). The cable and pulley system is powered by a reversible electric winch  48  (FIG. 7) having a rotating spool  50  around which a flexible cable  52  is wound. The cable is also drawn around a sheave or pulley  54  which may be mounted on a shaft  56  near the forward end of the frame of the trailer  10 . The cable  52  is also drawn around another pulley  58  which is mounted near the rear end of the trailer frame on a shaft  60 . The cable  52  may be a continuous loop which is drawn frequently around both of the pulleys  54  and  58  and the driven winch spool  50 . 
     Referring to FIG. 6 in particular, a chain  62  or other line may be secured to the cable  52 , as by means of a suitable fastener that may be attached to the cable at selected locations along the length of the cable. The opposite end of the chain  62  maybe equipped with a hook  64  that may be hooked to the axle  14  or some other part of the frame of the combine  12 . 
     The trailer  10  is used to transport two of the combines  12  at a time, one behind the other, over the road between agricultural fields or other sites. It is to be understood that the trailer may also be used to transport other types of large track or wheeled vehicles, one at a time or more than one at a time in substantially the same manner as for the combine  12 . 
     In order to load the first combine  12  onto the tractor  10 , the chain  62  is attached to the portion of the cable  52  adjacent to the rear end of the tractor, and the trailer is located adjacent to the front end of the combine such that the hook  64  can be hooked to the frame of the combine. The winch  48  is then operated in a direction to pull the top run of the cable  52  forwardly, thus pulling the combine  12  onto the trailer  10  with the rollers  36  moving onto and riding along the top flanges  20  of rails  18  as the combine is progressively pulled onto the trailer frame. As the top run of cable  52  moves forwardly, the chain  62  pulls the combine progressively in a forward direction until it has been fully loaded onto the frame at the desired position. The rollers  36  mate with and ride along the rails  18  in order to facilitate loading of the combine and pulling of it to the desired position with the cable and pulley system. The end flanges  36   a  butt the edges of the side rail flanges  20  to maintain the pulleys on the rails and guide the combine onto the trailer. Once the combine has been filly loaded onto the trailer, the rollers  36  can be suitably blocked to prevent them from moving. 
     If desired, a second combine canbe loaded onto the trailer  10  behind the first combine by unhooking the chain  62  from the first combine and operating the winch  48  in a direction to return the chain to the rear end portion of the trailer before hooking it onto the second combine and loading it in the same fashion as the first combine. Alternatively, the chain  62  can be detached from the cable  52  and reattached near the back end of the trailer. 
     The equipment on the trailer  10  can be unloaded by essentially reversing the loading process. The chain  62  can be positioned such that it can be hooked onto the front end portion of the rear combine  12 , and the winch can then be operated in a direction moving the chain rearwardly in order to move the rear combine off of the trailer. The front combine can similarly be unloaded, with the rollers  36  moving along the side rails  18  in both instances to facilitate the unloading operation. 
     From the foregoing it will be seen that this invention is one well adapted to attain all ends and objects hereinabove set forth together with the other advantages which are obvious and which are inherent to the structure. 
     It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims. 
     Since many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative, and not in a limiting sense.