Patent Publication Number: US-2009224512-A1

Title: Trailer

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to and the benefit of U.S. provisional patent application Ser. No. 61/085,776, filed Aug. 1, 2008, entitled TRAILER. This application is a continuation-in-part of U.S. patent application Ser. No. 11/609,319, filed Dec. 11, 2006, entitled TRAILER, now U.S. Pat. No. 7,475,901. 
     U.S. patent application Ser. No. 11/609,319 claims priority to and the benefit of U.S. provisional patent application Ser. No. 60/749,775, filed Dec. 12, 2005, entitled TRAILER; U.S. provisional patent application Ser. No. 60/752,194, filed Dec. 20, 2005, entitled TRAILER; U.S. provisional patent application Ser. No. 60/777,760, filed Mar. 1, 2006, entitled TRAILER; U.S. provisional patent application Ser. No. 60/810,088, filed Jun. 1, 2006, entitled TRAILER; U.S. provisional patent application Ser. No. 60/840,849, entitled TRAILER, filed Aug. 29, 2006; and U.S. provisional patent application Ser. No. 60/840,893, entitled TRAILER, filed Aug. 29, 2006. 
     These applications and patents are incorporated by reference in their entireties. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention generally relates to storage and/or transportation systems and, in particular, to trailers. 
     2. Description of Related Art 
     Conventional trailers may be attached to an automobile to allow the automobile to tow the trailer. Some known trailers have a relatively large size, which may allow the trailer to hold a large number of items or larger items. These relatively large trailers, however, may be difficult to maneuver and store. Other known trailers may have a relatively small size, which may be more easily maneuvered and stored than larger trailers. Disadvantageously, the smaller trailers may not be able to hold as many items and/or as large of items as the larger trailers. 
     BRIEF SUMMARY OF EMBODIMENTS OF THE INVENTION 
     A need therefore exists for a trailer that eliminates or diminishes the disadvantages and problems described above. 
     One aspect is a trailer that may be used to store and/or transport various items. The trailer may be selectively moved between an extended or use position and a collapsed or storage position. Advantageously, the trailer may be efficiently moved and/or stored in the collapsed or storage position. 
     Another aspect is a trailer that may include a bed and the bed may advantageously be disposed in one or more positions to allow the trailer to be used and stored. For example, the bed may include a plurality of panels that fold together to provide a more compact bed. 
     Yet another aspect is a trailer that may include a frame and the frame may move among a variety of positions to allow the trailer to be used and stored. For example, the frame may include a plurality of supports and the supports may fold together to provide a more compact frame. 
     Still another aspect is a trailer that may include an axle, which may be movable between one or more positions to allow the trailer to be disposed in the use and storage positions. For example, the axle may fold together to provide a more compact design. 
     A further aspect is a trailer that may include a pair of wheels that may be spaced apart a first distance when the trailer is in the extended or use position and a second distance when the trailer is in a collapsed or storage position. Advantageously, when the trailer is in the collapsed or storage position, one or both of the wheels may still be used, which may help in moving the collapsed trailer. 
     Another aspect is a trailer that may include an apparatus which assists in moving the trailer move between the extended or use position and the collapsed or storage position. The apparatus may include arms, wheels and a handle. The arms may contact or engage one wheel of the trailer and the handle may be used to manipulate the arms to lift the trailer&#39;s wheel away from the support surface. The apparatus may then be used to move the trailer between the extended or use position and the collapsed or storage position. 
     Still another aspect is a trailer that may include a pair of wheels that allow the trailer to be towed. The trailer may also include a separate wheel assembly that is sized and configured to assist in moving the trailer between the use and storage positions. For example, the wheel assembly may be sized and configured to move between a first position in which the wheel assembly engages a support surface and a second position in which the wheel assembly is spaced apart from the support surface. When the wheel assembly engages the support surface, one of the wheels of the trailer may be spaced apart from the support surface. This may allow the trailer to be easily moved between the extended position and the collapsed position. 
     Yet another aspect is a trailer that may include an arm which is sized and configured to be connected to a vehicle. The arm may be moved between an extended or use position and a collapsed or storage position. The trailer may also include a support assembly that may support the arm. In addition, the support assembly may facilitate moving the arm between the extended or use position and the collapsed or storage position. The support assembly, for example, may include a first support member and a second support member. The first support member may be pivotally connected to a frame of the trailer and pivotally connected to the arm. The second support member may be pivotally connected to a frame of the trailer and pivotally connected to the arm. 
     A further aspect is a trailer that may be quickly and easily moved between the use and storage positions. In particular, the trailer may be folded into the storage position to create a more compact and easily storable structure. Preferably, the trailer includes a multiple piece axle that is disposed in a generally aligned, straight configuration when the trailer is in the use position. When the trailer is being folded into the collapsed position, the center portion of the axle preferably moves towards the rear of the trailer and the center portion of the axle is folded together. Because the towing arm or tongue may be connected to the axle, the rearward movement of the axle may retract the towing arm while the trailer is being folded into the collapsed position. Advantageously, this may facilitate storage of the trailer because the towing arm may be disposed entirely or substantially beneath the bed or frame of the trailer. 
     A still further aspect is a trailer that may include components that fold in different planes when the trailer is moved from the use position to the storage position. For example, the axle may fold rearwardly and in a generally horizontal plane while the trailer bed and frame may fold upwardly and in a generally vertical plane. This may create a trailer with increased strength and rigidity because different components fold in different planes. In addition, when the axle is in the folded position, the folded sections of the axle may be disposed proximate or adjacent to each other. Similarly, when the bed and frame are in the folded position, the folded sections of the bed and frame may be disposed proximate or adjacent to each other. Advantageously, this may allow the trailer to be stored in a very compact configuration. 
     Yet another further aspect is a trailer that may include overlapping and/or interlocking portions. For example, when the trailer is in the use position, portions of the bed, frame and/or side walls may overlap and/or interlock. In particular, the bed may be constructed from two or more corrugated steel sections and these sections may overlap and/or interlock when the bed is in the collapsed position. This may create a bed with increased strength and structural integrity. Additionally, the side walls may be constructed from two or more sections and at least a portion of these sections may overlap and/or interlock to create side walls with increased strength and structural integrity. 
     Another aspect is a trailer that may include side walls or barriers that may be used for several different purposes. For example, the barriers may be connected to the trailer to create the side walls. The barriers may also be detached from the trailer to allow various sized items to be disposed in the trailer. In addition, the barriers may be used to create ramps to facilitate loading and unloading of the trailer. Further, the barriers may be pivotally connected to the trailer to facilitate folding of the trailer into the storage position. Significantly, one or more of the barriers may be interchangeable, which may make the trailer easier to assemble and use. 
     Still another aspect is a trailer that may include an actuating member or mechanism to facilitate moving the trailer between the use and storage positions. The actuating member or mechanism may include cables, pulleys, cranks, jacks and the like to help move the trailer between the use and storage positions. For example, the actuating member or mechanism may help pull the trailer into the storage position and push the trailer into the use position. Advantageously, the actuating member or mechanism may provide controlled movement of the trailer between the use and storage positions. Significantly, because the movement of the trailer may always be controlled, the trailer may not inadvertently or unexpectedly move, which may make the trailer easier to use. In addition, the actuating member or mechanism may help maintain the trailer in the use or storage positions, and prevent the trailer suddenly moving from the use or storage position. 
     A further aspect is a trailer that may include a towing arm or tongue and an actuating member or mechanism. The actuating member or mechanism may be connected to the towing arm or tongue. For example, the actuating member or mechanism may be connected to a front portion of the towing arm or tongue. The actuating member or mechanism may include a crank and the crank may be connected to and/or disposed proximate the front portion of the towing arm or tongue. Desirably, this may allow the crank to be readily used to help the actuating member or mechanism move the trailer between the use and storage positions. 
     Another further aspect is a trailer that may include a towing arm or tongue, an axle and an actuating member or mechanism. The actuating member or mechanism may include an adjustment assembly that may sized and configured to adjust the position of the arm and the axle. The adjustment assembly may include connecting members, a shaft and a sliding mechanism such as a carriage assembly. In particular, the connecting members may be pivotally or movably connected to the axle by fasteners, pins, brackets, connectors or the like. The connecting members may also be pivotally or movably connected to the carriage assembly by a fastener, pin, bracket, connector or the like. The carriage assembly may be coupled to the shaft. For example, the carriage assembly and the shaft may be threadably connected. Additionally, the shaft may be connected to the arm using a mount. Specifically, the shaft may be inserted through an opening in the mount and the position of the mount along the shaft may be generally fixed using any suitable means. The shaft may also be connected to a crank, handle and/or other device that may be used to rotate the shaft. Rotating the shaft may help move the arm and the axle between the extended and collapsed positions. For example, as the shaft is rotated in a first direction, the threads of the shaft may engage the threads of the carriage assembly to move the carriage assembly away from the mount. As the carriage assembly moves away from the mount, the connecting members may move the axle and the arm arm toward the extended position and away from the collapsed position. On the other hand, if the shaft is rotated in an opposing second direction, the threads of the shaft may engage the threads of the carriage assembly to move the carriage assembly towards the mount. As the carriage assembly moves towards the mount, the connecting members may move the axle and the arm toward the collapsed position and away from the extended position. Advantageously, the shaft may be rotated by a number of different types of devices such as a hand crank or a motor. If a motor is used, that may allow the trailer to be automatically opened and closed. In some embodiments, portions of the mount and the carriage assembly may be slidably and/or telescopically coupled. For example, the mount may include a tube, and the carriage assembly may include a tube that may be slidably and/or telescopically coupled to the tube of the mount. The tube of the mount may be connected to the arm using, for example, fasteners, pins, brackets, connectors, welds and/or any other suitable means. If desired, the crank, handle and/or other device used to rotate the shaft may be positioned to rotate in the same axis in which the shaft rotates or in a different axis. For example, in some embodiments, a coupler may be used to interconnect the shaft and the crank, handle and/or other device to allow the crank, handle and/or other device to be positioned at an angle relative to the shaft (such as about a 90 degree angle, an oblique angle or any other suitable angle), which may allow the crank, handle and/or other device to rotate in a different axis than the axis in which the shaft rotates. The coupler may also be configured to allow the crank, handle and/or other device to be generally aligned with the shaft, which may allow the crank, handle and/or other device to rotate in the generally same axis in which the shaft rotates. In some embodiments, the axle may include a first center portion and a second center portion pivotally or otherwise movably connected to the first center portion. The first center portion may include one or more elongated supports. The second center portion include one or more elongated supports. 
     Yet another aspect is a trailer that may include an improved suspension system. For example, the trailer may include a leaf spring type suspension system and the axle may be connected to the leaf spring. The bracket or structure used to attach the axle and/or wheel assembly to the leaf spring may help prevent the wheel from undesirably twisting while the trailer is being towed. Thus, the wheel may remain in the desired direction and orientation regardless of the forces applied to the wheel. 
     Another aspect is a folding trailer that may be capable of moving between a use position and a storage position. The folding trailer may include a frame including a front portion, a rear portion, a right side and a left side; a wheel disposed proximate the frame; an axle connected to the wheel, the axle being movable between a first position in which the axle is generally aligned along an axis and a second position in which the axle is disposed in a folded configuration; a towing arm movable between an extended position in which a portion of the towing arm extends beyond the front portion of the frame to facilitate attached to a towing vehicle and a collapsed position in which the towing arm is at least substantially disposed underneath the frame; and an adjustment assembly that is sized and configured to adjust the position of the axle between the first position and the second position, the adjustment assembly also being sized and configured to adjust the position of the towing arm between the extended position and the collapsed position. 
     Advantageously, the adjustment assembly may have different configurations and arrangements. For example, the adjustment assembly may include a track and a carriage assembly that is sized and configured to move along the track between a first position and a second position, the carriage assembly adjusting the positioning of the axle and the towing arm by moving between the first position and the second position of the track. The adjustment assembly may also include a shaft and a carriage assembly that is sized and configured to move along the shaft between a first position and a second position, the carriage assembly adjusting the positioning of the axle and the towing arm by moving between the first position and the second position of the shaft. In addition, the adjustment assembly may include a track, a shaft and a carriage assembly that is sized and configured to move along the track between a first position and a second position, the carriage assembly adjusting the positioning of the axle and the towing arm by moving between the first position and the second position of the track. The adjustment assembly may be sized and configured to selectively lock the axle and the towing arm in a desired position. The adjustment assembly may also be sized and configured to selectively lock the axle in the first position, the second position or a position between the first position and the second position. In addition, the adjustment assembly may be sized and configured to lock the towing arm in the collapsed position, the extended position or a position between the collapsed position and the extended position. 
     These and other aspects, features and advantages of the present invention will become more fully apparent from the following detailed description of preferred embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The appended drawings contain figures of preferred embodiments to further illustrate and clarify the above and other aspects, advantages and features of the present invention. It will be appreciated that these drawings depict only preferred embodiments of the invention and are not intended to limit its scope. The invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which: 
         FIG. 1  is a perspective view of an exemplary trailer, illustrating the trailer in an extended or use position; 
         FIG. 2  is a perspective view of a portion of the trailer shown in  FIG. 1 , illustrating the trailer without the bed; 
         FIG. 3  is a bottom perspective view of a portion of the trailer shown in  FIG. 2 ; 
         FIG. 4  is a top view of a portion of the trailer shown in  FIG. 2 ; 
         FIG. 5  is a perspective view of the trailer shown in  FIG. 1 , illustrating the trailer in a collapsed or storage position; 
         FIG. 6  is another perspective view of the trailer shown in  FIG. 1 , illustrating the trailer in a collapsed or storage position; 
         FIG. 7  is a bottom view of a portion of the trailer shown in  FIG. 6 ; 
         FIG. 8  is a bottom perspective view of the portion of the trailer shown in  FIG. 7 ; 
         FIG. 9  is a perspective view of an exemplary bed that may be used in connection with the trailer shown in  FIG. 1 ; 
         FIG. 10  is a bottom view of the bed shown in  FIG. 9 ; 
         FIG. 11  is a perspective view of a portion of the trailer shown in  FIG. 1 , illustrating the frame in a collapsed position; 
         FIG. 12  is another perspective view of the portion of the trailer shown in  FIG. 11 ; 
         FIG. 13  is a bottom perspective view of the portion of the trailer shown in  FIG. 11 ; 
         FIG. 14  is another bottom perspective view of the portion of the trailer shown in  FIG. 11 ; 
         FIG. 15  is a diagram of a top view of a portion of the trailer shown in  FIG. 1 , illustrating the frame and axle in the extended position; 
         FIG. 16  is a diagram of a side view of the trailer shown in  FIG. 15 ; 
         FIG. 17  is a diagram of a top view of a portion of the trailer shown in  FIG. 1 , illustrating the frame and axle in an exemplary collapsed positions; 
         FIG. 18  is a diagram of a side view of the trailer shown in  FIG. 17 ; 
         FIG. 19  is a diagram of a top view of a portion of the trailer shown in  FIG. 1 , illustrating the frame and axle in exemplary collapsed position; 
         FIG. 20  is a diagram of a side view of the trailer shown in  FIG. 19 ; 
         FIG. 21  is a diagram of a top view of a portion of the trailer shown in  FIG. 1 , illustrating the frame and axle in still another exemplary collapsed position; 
         FIG. 22  is a diagram of a side view of the trailer shown in  FIG. 21 ; 
         FIG. 23  is a bottom perspective view of a portion of the trailer shown in  FIG. 1 ; 
         FIG. 24  is another bottom perspective view of a portion of the trailer shown in  FIG. 1 ; 
         FIG. 25  is a perspective view of another exemplary trailer, illustrating the trailer in an extended or use position; 
         FIG. 26  is a perspective view of another exemplary bed that may be used in connection with the trailer; 
         FIG. 27  is a front view of the bed shown in  FIG. 26 ; 
         FIG. 28  is an enlarged front view of a portion of the bed shown in  FIG. 27 , illustrating exemplary components of the bed overlapping; 
         FIG. 29  is a front view of the bed shown in  FIG. 26 , illustrating exemplary components of the bed being spaced apart; 
         FIG. 30  is an enlarged front view of the portion of the bed shown in  FIG. 29 ; 
         FIG. 31  is a bottom perspective view of a portion of the trailer shown in  FIG. 25 ; 
         FIG. 32  is a top, partially exploded view of a portion of the trailer shown in  FIG. 25 ; 
         FIG. 33  is an enlarged perspective view of a portion of the trailer shown in  FIG. 32 ; 
         FIG. 34  is an enlarged perspective view of another portion of the trailer shown in  FIG. 25 ; 
         FIG. 35  is an enlarged perspective view of yet another portion of the trailer shown in  FIG. 25 ; 
         FIG. 36  is an enlarged perspective view of still another portion of the trailer shown in  FIG. 25 ; 
         FIG. 37  is a top perspective view of a portion of the trailer shown in  FIG. 25 ; 
         FIG. 38  is a top view of a portion of the trailer shown in  FIG. 25 ; 
         FIG. 39  is a bottom view of a portion of the trailer shown in  FIG. 25 ; 
         FIG. 40  is a perspective view of a portion of the trailer shown in  FIG. 25 , illustrating the trailer in an exemplary collapsed or storage position; 
         FIG. 41  is another perspective view of a portion of the trailer shown in  FIG. 25 , illustrating the trailer in an exemplary collapsed or storage position; 
         FIG. 42  is a bottom perspective view of a portion of the trailer shown in  FIG. 25 , illustrating the trailer in an exemplary collapsed or storage position; 
         FIG. 43  is a top perspective view of a portion of the trailer shown in  FIG. 25 , illustrating an exemplary arm and axle in an extended position; 
         FIG. 44  is a bottom perspective view of the arm and axle shown in  FIG. 43 ; 
         FIG. 45  is a top view of the arm and axle shown in  FIG. 43 ; 
         FIG. 46  is a top perspective view of the arm and axle shown in  FIG. 43 , illustrating the arm and axle in an exemplary collapsed position; 
         FIG. 47  is a perspective view of a portion of the trailer shown in  FIG. 25 , illustrating an exemplary arm and axle; 
         FIG. 48  is an exploded view of the portion of the trailer shown in  FIG. 47 ; 
         FIG. 49  is an enlarged exploded view of a portion of the trailer shown in  FIG. 43 , illustrating an exemplary connection of the arm and axle; 
         FIG. 50  is a perspective view of an exemplary apparatus that may be used to move the trailer between the extended and collapsed positions; 
         FIG. 51  is a perspective view of yet another exemplary trailer, illustrating the trailer in an extended or use position; 
         FIG. 52  is a left side view of the trailer shown in  FIG. 51 ; 
         FIG. 53  is a right side view of the trailer shown in  FIG. 51 ; 
         FIG. 54  is a partially exploded view of the trailer shown in  FIG. 51 ; 
         FIG. 55  is an enlarged perspective view of a left rear portion of the trailer shown in  FIG. 51 ; 
         FIG. 56  is an enlarged perspective view of a left front portion of the trailer shown in  FIG. 51 ; 
         FIG. 57  is an enlarged perspective view of a right front portion of the trailer shown in  FIG. 51 ; 
         FIG. 58  is an enlarged perspective view of a right rear portion of the trailer shown in  FIG. 51 ; 
         FIG. 59  is an enlarged perspective view of a right rear portion of the trailer shown in  FIG. 51 , illustrating an exemplary biasing member and an exemplary pin; 
         FIG. 60  is an enlarged perspective view of a right rear portion of the trailer shown in  FIG. 51 , illustrating an exemplary engaging member coupled to the pin shown in  FIG. 59 ; 
         FIG. 61  is another enlarged perspective view of the right rear portion of the trailer shown in  FIG. 51 ; 
         FIG. 62  is another enlarged perspective view of the left rear portion of the trailer shown in  FIG. 51 ; 
         FIG. 63  is another enlarged perspective view of the left rear portion of the trailer shown in  FIG. 51 ; 
         FIG. 64  is an enlarged top view of left rear portion of the trailer shown in  FIG. 51 ; 
         FIG. 65  is a perspective view of a rear portion of the trailer shown in  FIG. 51 . illustrating exemplary attachment members; 
         FIG. 66  is a perspective view of an exemplary barrier shown in  FIG. 51 ; 
         FIG. 67  is bottom perspective view of a portion of the trailer shown in  FIG. 51 ; 
         FIG. 68  is a perspective view of still another exemplary trailer, illustrating an exemplary support connected to a towing arm; 
         FIG. 69  is an enlarged perspective view of a portion of the trailer shown in  FIG. 51 . illustrating an exemplary locking member connective an exemplary latch to the towing arm; 
         FIG. 70  is an enlarged front perspective view of the portion of the trailer shown in  FIG. 69 ; 
         FIG. 71  is another enlarged front perspective view of the portion of the trailer shown in  FIG. 69 ; 
         FIG. 72  is an enlarged bottom perspective view a portion of the trailer shown in  FIG. 67 ; 
         FIG. 73  is a bottom perspective view of a portion of the trailer shown in  FIG. 51 , illustrating an exemplary adjustment assembly; 
         FIG. 74  is a rear perspective view of the adjustment assembly shown in  FIG. 73 ; 
         FIG. 75  is an exploded view of the adjustment assembly shown in  FIG. 73 ; 
         FIG. 76  is an enlarged, exploded view of a portion of the adjustment assembly shown in  FIG. 75 ; 
         FIG. 77  is another enlarged, exploded view of the adjustment assembly shown in  FIG. 73 ; 
         FIG. 78  is still another enlarged, exploded view of a portion of the adjustment assembly shown in  FIG. 73 ; 
         FIG. 79  is a right side perspective view of a portion of the trailer shown in  FIG. 15 , illustrating an exemplary suspension; 
         FIG. 80  is an enlarged perspective view of a portion of the trailer shown in  FIG. 79 ; 
         FIG. 81  is an exploded view of the portion of the trailer shown in  FIG. 80 ; 
         FIG. 82  is a perspective view of a portion of the trailer shown in  FIG. 79 , illustrating an exemplary bracket; 
         FIG. 83  is a perspective view of the bracket shown in  FIG. 82 ; 
         FIG. 84  is a perspective view of a portion of the trailer shown in  FIG. 79 , illustrating an exemplary bracket; 
         FIG. 85  is a perspective view of the bracket shown in  FIG. 84 ; 
         FIG. 86  is a perspective view of a portion of the trailer shown in  FIG. 79 , illustrating an exemplary bracket; 
         FIG. 87  is a perspective view of a portion of the trailer shown in  FIG. 79 , illustrating an exemplary plate; 
         FIG. 88  is a perspective view of a portion of the trailer shown in  FIG. 79 , illustrating an exemplary connector; 
         FIG. 89  is a perspective view of the connector shown in  FIG. 88 ; 
         FIG. 90  is a perspective view of another exemplary trailer, illustrating the trailer in an extended or use position; 
         FIG. 91  is a perspective view of the trailer shown in  FIG. 90 , illustrating the trailer in a collapsed or storage position; and 
         FIG. 92  is a perspective view of yet another exemplary trailer, illustrating the trailer in an extended or use position; 
         FIG. 93  is a perspective view of a portion of the trailer shown in  FIG. 92 , illustrating an exemplary arm and axle in an extended position; 
         FIG. 94  is a perspective view of a portion of the trailer shown in  FIG. 93 ; and 
         FIG. 95  is a perspective view of a portion of the trailer shown in  FIG. 94 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention is generally directed toward a trailer. The principles of the present invention, however, are not limited to trailers. It will be understood that, in light of the present disclosure, the trailer disclosed herein can be successfully used in connection with other types of storage and/or transportation systems. Additionally, to assist in the description of the trailer, words such as top, bottom, front, rear, right and left may be used to describe the accompanying figures. These figures may be, but are not necessarily, drawn to scale. It will be appreciated that the trailer and various components can also be located in a variety of desired positions—including various angles, sideways and even upside down. In addition, the trailer and various components of the trailer may have other sizes, shapes, configurations and arrangements that those shown in the drawings. A detailed description of the trailer now follows. 
     A trailer  10 , such as shown in  FIG. 1 , may be used to store and/or transport various items. An automobile or other motorized vehicles may pull or otherwise move trailer. Exemplary automobiles typically include, but are not limited to, a car, a truck and a sport utility vehicle (SUV). Other exemplary motorized vehicles include all-terrain vehicles (ATVs) and lawn tractors. Desirably, the trailer  10  may be easily moved and used for various suitable purposes such as camping, landscaping, travelling (such as to the beach or other recreational locations), moving items, and the like. 
     If desired, while being towed by a first vehicle, the trailer  10  may be used to carry a second vehicle, and the second vehicle may later be used to tow the trailer. For example, the second vehicle may comprise an all-terrain vehicle (ATV), a lawn tractor or the like, which may be sold with and loaded onto the trailer  10 . By selling the trailer  10  and the second vehicle together, a store may experience greater sales for both items because the store may offer the items for sale at a discounted price when they are sold together. Moreover, using the trailer  10  to carry the second vehicle may provide some customers the means for transporting the second vehicle home, which may have been otherwise too difficult for the customers. For instance, a customer may purchase the trailer and when the customer arrives home, he or she may remove the lawn tractor from the trailer and use the lawn tractor to move the trailer. It will be appreciated that the lawn tractor and trailer may be purchased together, individually or in other combinations depending, for example, upon the intended use of the trailer  10 . 
     As shown in  FIGS. 1-4 , the trailer  10  may include a towing arm  12  that may be sized and configured to be connected to a vehicle, which may pull the trailer. For example, the vehicle may include a hitch and the arm  12  may be sized and configured to be attached to the hitch. In particular, the arm  12  may include, or be connected to, a hitch coupler that may be sized and configured to be coupled to the hitch of the vehicle. The hitch coupler may be sized and configured to be coupled to a variety of differently sized and/or configured hitches, if desired. It will be appreciated that the arm  12  of the trailer may be connected to a variety of other suitable vehicles, connectors and/or structures. 
     As shown in  FIGS. 1-3 , the trailer  10  may include one or more wheels  14 ,  16 . The wheels  14 ,  16  may advantageously help the trailer  10  be pulled or otherwise moved. The wheels  14 ,  16  may have a variety of suitable shapes, sizes, configurations and arrangements. The trailer  10  may also include any suitable number of wheels. For example, the trailer  10  may have four wheels to enable the trailer, for example, to carry heavier loads. 
     As shown in  FIG. 1 , the trailer  10  may include a bed or floor  18  upon which one or more items carried by the trailer may rest. The trailer may also include a frame  20  that may help support and/or strengthen the bed  18 . It will be appreciated that the trailer  10  does not require the bed  18  and that one or more items may, for example, rest upon the frame  20  as the trailer carries those items. 
     The trailer  10  may also include one or more barriers, such as side walls or end walls, and these barriers are preferably disposed about the outer periphery or edges of the bed  18 . In greater detail, the trailer may include a front barrier, a rear barrier, a left barrier and/or a right barrier; and the barriers may be connected to, or form part of, the frame  20 . Desirably, the front, rear, left, and right barriers may be sized and configured to help prevent items from leaving corresponding front, rear, left and right portions of the bed  18  and/or the trailer  10 . The barriers may be connected to the frame using one or more fasteners (such as bolts), but the barriers may also be connected to the frame using other type of fasteners, adhesives, welding and the like. Advantageously, the barriers may be connected to any suitable portions of the trailer  10  and the trailer may be used with or without the barriers. 
     In further detail, as shown in  FIG. 1 , the trailer  10  may include barriers  22 ,  24 ,  26 ,  28 . The barriers  22 ,  24  may be positioned on the left and right sides of the bed  18  and, as shown in  FIG. 1 , the barriers  26 ,  28  may be positioned at the rear of the trailer  10 . The barriers  22 ,  24 ,  26 ,  28  preferably have a generally fence-shaped configuration including at least one generally horizontal railing and/or at least one generally vertical post. The barriers  22 ,  24 ,  26 ,  28 , however, could have other suitable sizes, shapes, configurations and the like. For example, the barriers  22 ,  24 ,  26 ,  28  may be solid walls, railings. While the trailer  10  may have any suitable number and type of barriers, the barriers are not required. 
     The barriers  22 ,  24 ,  26 ,  28  may pivot or move relative to the trailer  10 . For example, the rear barriers  26 ,  28  may pivot, move or be removed to allow for longer items (such as large pieces of plywood or drywall) to extend past the rear edge of the bed  18 . Similarly, the side barriers  22 ,  24  may pivot, move or be removed to allow the items to extend past the sides of the bed  18 . 
     The barriers  22 ,  24 ,  26 ,  28 , may also be used for different purposes and functions. For example, as shown in  FIG. 1 , the barriers  26 ,  28  may be used as a ramp to facilitate loading and/or unloading of the trailer  10 . In particular, one end of the barriers  26 ,  28  may be attached to the rear portion of the trailer  10  and the other ends of the barriers may rest upon the support surface. This may allow objects to be wheeled or carried into and out of the trailer  10 . After using the barriers  26 ,  28  as a ramp, the barriers may be attached to the trailer  10 . For example, the barrier  26  may be attached to the front of the trailer  10  to form a front barrier and the barrier  28  may be connected to the rear of the trailer to form a rear barrier. Advantageously, the barriers  22 ,  24 ,  26 ,  28  may help reinforce and/or strengthen the trailer  10 . In addition, the barriers  22 ,  24 ,  26 ,  28  may be interchangeably connected to the trailer  10 , which may facilitate manufacturing, assembly and use of the trailer. For instance, the front and rear barriers  26 ,  28  may be interchangeable, and the side barriers  22  and  24  may be interchangeable. 
     As shown in  FIGS. 1-12 , the trailer  10  may be selectively collapsed and/or extended. In particular, the trailer  10  may be selectively moved between an extended or use position and a collapsed or storage position. Advantageously, the trailer  10  may be more efficiently stored when positioned in the storage position, as shown in  FIGS. 5-8 . As discussed in further detail below, the wheels  14 ,  16 , the bed  18 , the frame  20  and/or other portions of the trailer  10  may include one or more components and move among a variety of different positions to facilitate movement of the trailer  10  between the use and storage positions. 
     For example, the bed  18  may include two or more sections to facilitate folding of the bed. In particular, as shown in  FIGS. 1 ,  5 - 6  and  9 - 10 , the bed  18  may include four sections or panels  30 ,  32 ,  34 ,  36 . As shown in  FIG. 1 , the panels  32 ,  34  may be positioned in a generally horizontal plane and level orientation when the trailer  10  is in the use position. The panels  32 ,  34 , however, may be positioned in a generally vertical plane and upright orientation when the trailer is in the storage position, as shown in  FIGS. 5-6 . In particular, as the trailer is collapsed, the panels  32 ,  34  may move towards the generally upright orientation and away from the generally level orientation, and the panels  32 ,  34  may move towards the generally level orientation and away from the generally upright orientation as the trailer is extended. 
     The panels  30 ,  32 ,  34 ,  36  may be constructed from blow-molded plastic. The blow-molded plastic panels may include a hollow interior portion formed during the blow-molding process. In addition, the blow-molded plastic panels may include an upper surface or wall and a lower surface or wall that are spaced apart from each other, and the blow-molded plastic panels may include one or more depressions (referred to as “tack offs” or “kiss offs”) that are sized and configured to strengthen the blow-molded plastic panels. The blow-molded plastic panels may be relatively lightweight, strong, durable and/or weather resistant. In addition, the blow-molded plastic panels may be interconnected using, for instance, a living hinge that may be integrally formed with the panels as part of a unitary, one-piece structure during the blow-molding process. For example, the panels  30 ,  32  may be interconnected via a living hinge  38 , and the panels  34 ,  36  may be interconnected via a living hinge  40 . 
     It will be appreciated, however, that the panels  30 ,  32 ,  34 ,  36  may be constructed from other materials, such as wood, metal and the like, and the panels may be constructed using other molding and manufacturing processes. For example, the bed  18  may include panels  30 ,  32 ,  34 ,  36  constructed from metal, such as galvanized steel, and the panels may be corrugated, if desired. Advantageously, the corrugated metal panels may form a strong and sturdy bed  18  for the trailer. In addition, when the trailer  10  is in the use position, at least a portion of the panels may overlap and/or interlock. Significantly, this may increase the strength and/or structural integrity of the trailer  10 . In addition, the overlapping and/or interlocking panels  30 ,  32 ,  34 ,  36  may help create a stronger, more rigid bed  18 . The panels  30 ,  32 ,  34 ,  36  may also have other suitable shapes, sizes, configuration and arrangements depending, for example, upon the size and shape of the bed  18  and/or the intended use of the trailer  10 . 
     As shown in  FIGS. 2-4 , the frame  20  may include one or more supports, such as elongated supports  42 ,  44 ,  46 ,  48 ,  50 ,  52 ,  54 . The supports  42 ,  44  may extend longitudinally along the length of trailer  10  and these supports preferably extend from the front to the rear of the trailer. The supports  46 ,  48 ,  50 ,  52 ,  54  may extend laterally along the width of the trailer  10  and these supports preferably extend between the left and right sides of the trailer. It will be appreciated that the frame  20  may include any suitable number of supports that extend longitudinally, laterally and/or other suitable orientations and arrangements depending, for example, upon the size, configuration or intended use of the trailer  10 . 
     As best shown in  FIG. 4 , the supports  46 ,  48 ,  50 ,  52 ,  54  may be disposed between and connected to the supports  42 ,  44 . In addition, the supports  46 ,  48 ,  50 ,  52 ,  54  preferably include multiple components or sections to facilitate folding of the trailer  10 . For example, the support  46  may include four sections  56 ,  58 ,  60 ,  62 . These sections  56 ,  58 ,  60 ,  62  are preferably interconnected by hinges to allow the trailer  10  to fold. Similarly, the support  48  may include portions  64 ,  66 ,  68 ,  70 ; the support  50  may include portions  72 ,  74 ,  76 ,  78 ; the support  52  may include portions  80 ,  82 ,  84 ,  86 ; and the support  54  may include portions  88 ,  90 ,  92 ,  94 . As shown in  FIG. 4 , the end portions  56 ,  64 ,  72 ,  80 ,  88  may be connected to the support  42  and the end portions  62 ,  70 ,  78 ,  86 ,  94  may be connected to the support  44 . It will be understood that the supports may include any suitable number of sections or components depending, for example, upon the structure and intended use of the trailer  10 . 
     As shown in  FIGS. 1 ,  5  and  6 , the bed  18  may be connected to the frame  20 . For example, the end portions  56 ,  64 ,  72 ,  80 ,  88  of the supports of the frame  20  may be connected to the panel  30  of the bed  18 . Similarly, the central portions  58 ,  66 ,  74 ,  82 ,  90  of the supports of the frame  20  may be connected to the panel  32  of the bed  18  and the central portions  60 ,  68 ,  76 ,  84 ,  92  of the supports of the frame  20  may be connected to the panel  34  of the bed  18 . The end portions  62 ,  70 ,  78 ,  86 ,  94  of the supports of the frame  20  may be connected to the panel  36  of the bed  18 . 
     As mentioned above, the supports  46 ,  48 ,  50 ,  52 ,  54  may include a plurality of pivotally or movably interconnected components. For example, the center portions  58 ,  66 ,  74 ,  82 ,  90  may be pivotally connected to the end portions  56 ,  64 ,  72 ,  80 ,  88 , respectively, and pivotally connected to the other center portions  60 ,  68 ,  76 ,  84 ,  92 , respectively. The center portions  60 ,  68 ,  76 ,  84 ,  92  may also be pivotally connected to the end portions  62 ,  70 ,  78 ,  86 ,  94 , respectively. In addition, the end portions  56 ,  64 ,  72 ,  80 ,  88  may be connected to the support  42  and the end portions  62 ,  70 ,  78 ,  86 ,  94  may be connected to the support  44 . Thus, the various components may be interconnected to form at least a portion of the frame  20 . 
     Because the supports  46 ,  48 ,  50 ,  52 ,  54  may include a plurality of pivotally or otherwise movably interconnected components, the supports may move among a variety of positions. Advantageously, this may help the trailer  10  move between the collapsed and extended positions. For example, as shown in  FIGS. 2-4  and  15 - 16 , the supports  46 ,  48 ,  50 ,  52 ,  54  may be positioned in a use or first position when the trailer  10  is in the use position, as shown in  FIG. 1 . Thus, in the use position, the various components or portions of the supports  46 ,  48 ,  50 ,  52 ,  54  may be generally aligned and disposed in the same plane. In addition, the supports  46 ,  48 ,  50 ,  52 ,  54  may be aligned in a generally parallel configuration and disposed in the same plane. The supports  46 ,  48 ,  50 ,  52 ,  54  may be disposed in a collapsed or second position when the trailer  10  is in the collapsed or storage position as shown in  FIGS. 5-8 ,  11 - 14  and  17 - 20 . As the trailer  10  is collapsed, the supports  46 ,  48 ,  50 ,  52 ,  54  may move towards the second position and away from the first position. 
     In greater detail, when the supports  46 ,  48 ,  50 ,  52 ,  54  are in the collapsed position shown in  FIGS. 5-8 ,  11 - 14  and  17 - 18 , the center portions of the supports are preferably disposed proximate or adjacent to each other and disposed in a generally upright configuration. In particular, the center portions  58 ,  60 ; the portions  66 ,  68 ; the portions  74 ,  76 ; the portions  82 ,  84 ; and the portions  90 ,  92  may be folded together in a generally upright orientation. On the other hand, when the supports  46 ,  48 ,  50 ,  52 ,  54  are in the collapsed position, as shown in  FIGS. 21-22 , the center portions  58 ,  60 ; the portions  66 ,  68 ; the portions  74 ,  76 ; the portions  82 ,  84 ; and the portions  90 ,  92  may be folded together in a generally level orientation and may extend forwardly. It will be appreciated that the supports  46 ,  48 ,  50 ,  52 ,  54  may have other suitable arrangements and configuration in the use and storage positions. It will also be appreciated that the frame  20  may have other suitable arrangements and configurations depending, for example, upon the size and/or intended use of the trailer  10 . 
     As shown in  FIGS. 2-3  and  15 , the trailer  10  may include an axle  96 . The axle  96  may extend between and interconnect the wheels  14 ,  16 . To facilitate folding of the trailer  10  into the storage position, the axle  96  preferably includes pivotally or otherwise movably connected portions. In particular, the axle  96  may include four sections or portions  98 ,  100 ,  102 ,  104  that are interconnected. For example, one end portion  98  may be connected to the wheel  14  and the other end portion  104  may be connected to the wheel  16 . The first center portion  100  may be pivotally or otherwise movably connected to the end portion  98  and the second center portion  102 ; and the second center portion  102  may be pivotally or otherwise movably connected to the end portion  104  and the second center portion  100 . 
     Advantageously, by including a plurality of pivotally or otherwise movably interconnected components, the axle  96  may allow the trailer  10  to be moved between the use and storage positions. For example, as shown in  FIGS. 2-4  and  15 - 16 , the axle  96  may be positioned in an extended or first position when the trailer  10  is in the use position, as shown in  FIG. 1 , and in a collapsed or second position when the trailer is in the storage position as shown in  FIGS. 5-8 ,  11 - 14  and  17 - 22 . As the trailer  10  is collapsed, the axle  96  may move towards the second position and away from the first position, and the axle may move towards the first position and away from the second position as the trailer is extended. 
     In greater detail, when the axle  96  is in the collapsed position as shown in  FIGS. 5-8 ,  11 - 14  and  17 - 22 , the center portions  100 ,  102  may be folded together. Specifically, the center portions  100 ,  102  of the axle  96  may be folded in a generally level orientation and the portions may be folded rearwardly as shown in  FIGS. 5-8 ,  11 - 14  and  17 - 18 , or forwardly as shown in  FIGS. 21-22 . Advantageously, the various portions  98 ,  100 ,  102 ,  104  of the axle  96  may remain in generally the same plane in both the extended and storage positions. It will be appreciated, however, that the axle  96  may be folded or disposed in other suitable directions, planes, positions and the like. 
     In addition, when the axle  96  in the collapsed position shown in  FIGS. 19-20 , the center portions  100 ,  102  may be folded together in a generally upright orientation. When folded in a generally upright orientation, the center portions  100 ,  102  may be folded upwardly as shown in  19 - 20 , downwardly, or in other suitable directions. 
     Preferably, when the trailer  10  is in the use or extended position, the portions of the axle  96  are generally aligned. In particular, if the axle  96  includes four portions  98 ,  100 ,  102 ,  104 , then these portions are preferably generally aligned along an axis. Advantageously, this may help create a strong and rigid axle  96  for the trailer  10 . The portions of the axle  96 , however, do not have to be aligned in a straight line and one or more portions of the axle may be disposed at an angle when the trailer  10  is in the collapsed position. For example, the center portions  100 ,  102  may be slightly angled rearwardly to facilitate moving the center portions of the axle rearwardly. For instance, the center portions  100 ,  102  may be angled rearwardly between about one and about five degrees to facilitate folding of the trailer  10 . On the other hand, the center portions  100 ,  102  may be angled forwardly, such as between about one and about five degrees, to help prevent the axle  96  from inadvertently moving rearwardly. 
     While the axle  96  is shown in the accompanying figures as having four sections or portions that are pivotally connected, it will be appreciated that the axle could have any suitable number of sections. Additionally, it will be appreciated that the axle  96  could other suitable shapes, sizes, arrangements and configurations depending, for example, upon the specific configuration of the trailer  10  or intended use of the trailer. 
     As shown in  FIGS. 3-4 , the arm  12  may be connected to a portion of the axle  96 , such as the center portion  100  and/or the center portion  102 . Advantageously, if the center portions  100 ,  102  are folded rearwardly and the arm  12  is connected to the center portions, then the arm may also move rearwardly. Significantly, this may create a more compact trailer  10  that is easier to store when the trailer  10  is in the collapsed position. As shown in  FIGS. 4 and 7 , the center portions  100 ,  102  and the arm  12  may be pivotally or movably interconnected using, for example, a suitable fastener or pivot pin  106 ; one or more brackets or connectors  108 ,  110 ; and/or other suitable means. 
     The brackets or connectors  108 ,  110  may help maintain the axle  96  in the desired position when the trailer  10  is in the extended or use position. For example, the brackets  108 ,  110  may help maintain the axle  96  in a generally aligned configuration. In addition, the brackets  108 ,  110  may help prevent the axle  96  from moving forwardly, upwardly and/or downwardly when the trailer  10  is in the use position. In particular, the brackets  108 ,  110  may include upper, lower and/or rear portions that contact corresponding upper, lower and/or rear portions of the center portions  100 ,  102  of the axle  96  to maintain the axle in the desired positions. Thus, the brackets  108 ,  110  may be sized and configured to maintain at least a portion of the axle  96  in the desired position when the trailer  10  is in the use position, and the brackets may allow the trailer to be quickly and easily moved in to the collapsed position. 
     In addition the brackets  108 ,  110  may help position the center portions  100 ,  102  of the axle  96  at a slight angle when the trailer  10  is in the use position. For example, as mentioned above, the brackets  108 ,  100  may position the center portions  100 ,  102  of the axle  96  at a slight rearward angle, such as less than about five or ten degrees, so that when the trailer  10  is moved from the use position to the collapsed position, the axle may quickly and easily move rearwardly. However, the brackets  108 ,  100  may position the center portions  100 ,  102  of the axle  96  at a slight forward angle, such as less than about five or ten degrees, to help prevent the axle from unintentionally moving rearwardly. It will be appreciated that the brackets  108 ,  100  could have other suitable configurations depending, for example, upon the size and configuration of the axle  96  and/or trailer  10 . 
     As shown in  FIG. 4 , the frame  20  may also include one or more connecting members  112 , which may be connected to the supports  46 ,  48 ,  50 ,  52 , and  54 . The connecting members  112  may advantageously help reinforce, strengthen and maintain the frame  20  and/or the supports  46 ,  48 ,  50 ,  52 ,  54  in the desired positions. In addition, the connecting members  112  may help the supports  46 ,  48 ,  50 ,  52  move collectively between the use and storage positions. It will be appreciated, however, that the frame  20  does not require connecting members  112  and that the supports may move independently between the use and storage positions, if desired. 
     As shown in  FIGS. 1-4  and  15 , the wheels  14 ,  16  may be spaced apart at a first distance when the trailer  10  is in the use position, and the wheels may be spaced apart at a second, smaller distance when the trailer is in the storage position as shown in  FIGS. 5-8 ,  17 ,  19 ,  21 . In particular, the wheels  14 ,  16  may move generally towards each other as the trailer is collapsed and may move generally away from each other as the trailer is extended. Advantageously, when the trailer  10  is in the collapsed or storage position, the wheels  14 ,  16  may be positioned for use, which may help in moving the collapsed trailer. Because the wheels  14 ,  16  may move along the same axis between the use and storage positions, this may allow the trailer  10  to be moved on its wheels in the use position, storage position and intermediate positions, if desired. 
     In greater detail, when the trailer  10  is in the use position, the wheels  14 ,  16  are preferably spaced apart approximately the length of the axle  96 . Thus, if the axle  96  has a length of about five feet in the extended position, then the wheels  14 ,  16  are preferably spaced apart about the same distance. On the other hand, when the trailer  10  is in the collapsed position, then the wheels  14 ,  16  are preferably aligned in the same direction and in a generally parallel configuration as when the trailer is in the use position, but the wheels are spaced much closer together. For example, the wheels  14 ,  16  may be spaced apart generally equal to or less than one-half, one-quarter or one-eighth the overall length of the axle  96  when the trailer  10  is in the storage position. 
     When the trailer  10  is in the storage position, the ends  98 ,  104  of the axles  96  connected to the wheels  14 ,  16  may be disposed proximate or adjacent to each other. Further, as discussed above, the center portions  100 ,  102  of the axle  96  may be disposed proximate or adjacent to each other. In addition, because the center portions  100 ,  102  of the axle  96  preferably move rearwardly, the arm  12  may also be drawn rearwardly and at least a portion of the arm may be disposed between the center portions of the axle The arm  12  may also be at least partially disposed between the ends  98 ,  104  of the axle  96  and the wheels  14 ,  16  when the trailer  10  is in the collapsed position. Thus, the axle  96  and the arm  12  may move rearwardly while the wheels  14 ,  16  are moved towards each other when the trailer  10  is moved into the storage position. Additionally, the various portions of the axle  96  and the arm  12  preferably remain in generally the same plane when the trailer  10  is in the collapsed and extended positions. 
     As discussed above, portions of the bed  18  and frame  20  are preferably disposed in different planes when the trailer  10  is in the collapsed end use positions. For example, the bed  18  and frame  20  are preferably aligned in a generally horizontal plane when the trailer  10  is in the use position. However, when the trailer  10  is in the collapsed position, at least the center portions of the bed  18  and the frame  20  are disposed in an upright or vertical configuration. In particular, the center portions of the bed  18  and the frame  20  may be disposed in a generally upright configuration and in generally aligned planes. Therefore, when the trailer  10  is in the use position, the arm  12 , bed  18  frame  20  and the axle  96  may be disposed in generally parallel, horizontal planes. When the trailer  10  is in the collapsed position, the arm  12  and axle  96  preferably move in one direction and remain in generally the same horizontal plane while the center portions of the bed  18  and frame  20  move in a different direction and into different planes. Advantageously, this may help create a trailer  10  with increased rigidity and strength. It may also create a more compact trailer  10  in the collapsed position. 
     The trailer  10  is preferably constructed from relatively strong and durable materials. For example, the frame  20 , barriers  22 ,  24 ,  26 ,  28 , axle  96  and other portions of the trailer  10  may be constructed from metal (such as steel) or other relatively strong and durable materials. It will be appreciated that the trailer  10  and any portions thereof may be constructed from other suitable materials. 
     Advantageously, the trailer may have a variety of suitable arrangements and configurations. For example, as shown in  FIGS. 25-49 , another exemplary trailer  114  may include parts, features and aspects similar to that described above. The trailer  114  may also have a size, shape, configuration and arrangement similar to that described above. The trailer  114 , however, could also have different parts, features, aspects, sizes, shapes, configurations and arrangements depending, for example, upon the intended use of the trailer. 
     As shown in  FIGS. 25-30 , the trailer  114  may include a bed  116  with two or more components that may have interlocking and/or overlapping portions. For example, the bed  116  may include a pair of corrugated portions  118 ,  120  that may interlock and/or overlap to help construct the bed. The corrugated portions  118 ,  120  preferably interlock and/or overlap when the bed  116  is in the use position, and the corrugated portions are preferably spaced apart when the bed is in the storage position. The corrugated portions  118 ,  120  are desirably formed of steel sheet metal and/or other suitable materials. Advantageously, the corrugated portions  118 ,  120  may help disperse impacts and forces applied to the bed  116 . Further, the overlapping and/or interlocking portions  118 ,  120  may help reinforce each other. It will be appreciated, that the bed  116  may include any suitable number of portions which interlock and/or overlap. It will also be appreciated that the bed  116  may consist of a single, unitary structure and the portions, if any, need not be corrugated, interlock or overlap. If desired, the upper surface of the bed  116  may be treated with a rubberized surface finish, which may reduce slippage and may reduce damage from impact when compared to other materials and finishes. 
     As shown in  FIG. 31 , the trailer  114  may include a wheel assembly  122  that includes at least one wheel  124 . The wheel assembly  122  may be sized and configured to help move the trailer  114  between the use position and the storage position. In particular, the wheel assembly  122  may be sized and configured to pivot or move between a first position in which the wheel  124  engages a support surface and a second position in which the wheel is spaced apart from the support surface. When the wheel  124  of the wheel assembly  122  engages the support surface, the trailer  114  may be more easily moved between the use position and the storage position. For example, when the wheel  124  of the wheel assembly  122  engages the support surface, the wheel  126  of the trailer  114  is preferably spaced apart from the support surface to allow the trailer to more readily moved between the use and storage positions. 
     In greater detail, when the wheel assembly  122  is in the first position, the wheel  124  preferably supports at least a portion of the load on the trailer wheel  126 . Thus, when the trailer  114  is moved from the use to the collapsed position, the trailer wheel  126  can be more easily moved relative to the support surface. It will be appreciated that the wheel assembly  122  could have a variety of suitable arrangements, configurations and components depending, for example, upon the intended use of the trailer  114 . 
     The wheel assembly  122  may be lockable and unlockable in the first and second positions. For example, the trailer may include a locking hinge, locking pin or other structure to lock the wheel assembly  122  in a desired position. Exemplary locking hinges which may be used in connection with the wheel assembly  122  are disclosed in U.S. patent application Ser. No. 10/843,037, filed May 10, 2004 and entitled PORTABLE FOLDING TABLE WITH LOCKING HINGE, the disclosure of which is incorporated by reference. 
     As shown in  FIGS. 31-32 ,  37 - 39  and  41 - 44 , the trailer  114  may include an arm  128  that is sized and configured to move between an extended or use position and a collapsed or storage position. As discussed below, the arm  128  preferably moves between the use and storage positions when the trailer  114  moves between the use and storage positions. The trailer  114  may also include a support assembly  130  that supports the arm  128  and facilitates movement of the arm between the extended and collapsed positions. As shown in  FIGS. 31 and 39 , the support assembly  130  may include a first support member  132  and a second support member  134 . Each of the support members  132 ,  134  may include a first portion that is pivotally or otherwise movably connected to the trailer  114  and a second portion that is pivotally or otherwise movably connected to the arm  128 . It will be appreciated that the support assembly  130  may include a variety of the suitable components arranged in various suitable configurations. 
     As shown in FIGS.  25  and  31 - 32 , the trailer  114  may include a front barrier  136  and a rear barrier  138  that are selectively attached to the trailer. Advantageously, the front and rear barriers  136 ,  138  may be used as a ramp to facilitate loading and/or unloading of the trailer. For instance one end of the front barrier  136  and one end of the rear barrier  138  may be attached to the rear portion of the trailer  114  and the other ends of the barriers may rest upon the support surface. This may allow objects to be wheeled or carried into and out of the trailer  114 . After using the front and rear barriers  136 ,  138  as a ramp, the front and rear barriers may be selectively reattached to the front and rear of the trailer  10 , which may help reinforce and/or strengthen the side barriers of the trailer. Advantageously, the front and rear barriers  136 ,  138  may be interchangeable, which may make the trailer easier to manufacture, assemble and use. 
     As shown in  FIGS. 34 and 36 , the rear portion of the trailer  114  may include one or more attachment members  140  that are sized and configured to attach the barriers  136 ,  138  to the rear portion of the trailer for use as a ramp. In addition, as shown in  FIGS. 32-36 , the trailer  114  may include slots  142  that are sized and configured to receive a portion of either of the barriers  136 ,  138  to connect the barriers to the trailer in a generally upright position as shown in  FIG. 25 . The slots  142  may be sized and configured to connect the barriers  136 ,  138  to the trailer using a snap fit, a friction fit and/or an interference fit. As best seen in  FIG. 33 , the slots  142  may be formed by a pair of flanges  144  or other suitable structures. 
     As shown in  FIG. 37 , the trailer  114  may include a frame  146 , which may be connected to the bed  116 . The frame  146  may include one or more supports, such as elongated supports  148 ,  150 ,  152 ,  154 ,  156 ,  158 ,  160 . The supports  148 ,  150  preferably extend longitudinally along the length of trailer  114  between the trailer&#39;s front and rear; and the supports  152 ,  154 ,  156 ,  158 ,  160  preferably extend laterally along the width of the trailer between the trailer&#39;s left and right sides. The supports  152 ,  154 ,  156 ,  158 ,  160  may extend between and interconnect the supports  148 ,  150 ; and the supports  152 ,  154 ,  156 ,  158 ,  160  may include a plurality of pivotally or otherwise movably interconnected components. For example, as shown in  FIGS. 25 ,  32 - 33  and  37 , the supports  152 ,  154 ,  156 ,  158 ,  160  may be connected to the supports  148 ,  150  using one or more hinges  162 . 
     As best seen in  FIGS. 25 and 33 , a portion of the hinges  162  may be sized and configured to provide a tie-down  164  when, for example, the trailer  114  is in the extended or use position. The tie-down  164  may advantageously be used to “tie down” or otherwise secure items to the trailer  114  using ropes, chains, cables, elastic cords, and the like. In further detail, the hinges  162  may include a pivot pin  166 . As shown in  FIG. 33 , the pivot pin  166  may be spaced apart from the bed  116  and/or the frame  146 , which may facilitate the attachment of ropes, chains, cables, elastic cords, and the like to the pivot pin. Because the hinges  162  may be used to provide tie-downs  164 , the trailer  114  does not require any additional tie-downs, which may be time consuming to manufacture and/or may increase the cost of the trailer  114 . 
     As shown in  FIGS. 42-49 , the trailer  114  may include an axle  170  that extends between and interconnect the wheels  14 ,  16 . The axle  170  preferably includes pivotally or otherwise movably connected portions. In particular, the axle  170  may include four portions  172 ,  174 ,  176 ,  178 . For example, the first portion  172  may be connected to a first wheel  180  and the fourth portion  178  may be connected to a second wheel  182 . The second portion  174  may be pivotally or otherwise movably connected to the first portion  172  and the arm  128  using, for example, a suitable fastener or pivot pin; one or more brackets or connectors  184 ; and/or other suitable means. The third portion  176  may be pivotally or otherwise movably connected to the fourth portion  178  and the arm  128  using, for example, a suitable fastener or pivot pin; one or more brackets or connectors  184 ; and/or other suitable means. 
     It will be understood that the axle  170  may have a variety of different configurations and arrangements depending, for example, upon the intended use of the trailer  114 . For example, as shown in  FIG. 48 , the center portions  174 ,  176  of the axle  170  may be constructed from elongated supports. Specifically, the center portion  174  may be constructed from elongated supports  224 ,  226 ; and the center portion  176  may be constructed from elongated supports  228 ,  230 . The elongated supports may, for example, help prevent twisting or torque of the axle  170 . The elongated supports may also increase the strength of the axle  170  and/or facilitate connection of the axle to the arm  128  and/or the wheels. It will be appreciated, however, that the center portions  174 ,  176  of the axle  170  may have a variety of others suitable components and configurations. In addition, it will be appreciated that the axle  170  may have other suitable components and configurations depending, for example, upon the intended use of the trailer  114 . 
     Advantageously, by including a plurality of pivotally or movably interconnected components, the axle  170  may move among a variety of positions to allow the trailer  114  to move between the use and storage positions. For example, as shown in  FIGS. 31-32  and  37 - 39 , the axle  170  may be positioned in a first or extended position when the trailer  114  is in the use position, as shown in  FIG. 25 , and in a second or collapsed position when the trailer is in the storage position as shown in  FIGS. 40-42 . As the trailer  114  is collapsed, the axle  170  may move towards the second position and away from the first position, and the axle may move towards the first position and away from the second position as the trailer is extended. 
     As shown in  FIGS. 42-49 , the arm  128  may be connected to a portion of the axle  170 , such as the second portion  174  and/or the third portion  176 . Advantageously, if the second and third portions  174 ,  176  are folded rearwardly and the arm  128  is connected to the second portion  174  or the third portion  178 , then the arm may also move rearwardly. Significantly, this may create a more compact trailer  114 , which may be easier to store. The second portion  174 , the third portion  176  and the arm  128  may be pivotally or otherwise movably interconnected using, for example, a suitable fastener or pivot pin; one or more brackets or connectors  184 ; and/or other suitable means. 
     As shown in  FIG. 49 , the trailer  114  may include an actuating member, actuating mechanism or adjustment assembly  186  that is sized and configured to adjust the position of the arm  128  and the axle  170  when the trailer  10  is moved between the extended and collapsed positions. In addition, the adjustment assembly  186  may be sized and configured to secure or lock the arm  128  and/or the axle  170  in a desired position, such as the use or storage positions. Further, the adjustment assembly  186  may be sized and configured to move the trailer  114  between the collapsed and extended positions. For example, as discussed in more detail below, the adjustment assembly  186  may help pull the trailer into the storage position and push the trailer into the use position. The adjustment assembly  186  may also provide controlled movement of the trailer  114  between the use and storage positions. Significantly, because the movement of the trailer  114  may always be controlled, the trailer may not inadvertently or unexpectedly move, which may make the trailer easier to use. In addition, the adjustment assembly  186  may help maintain the trailer  114  in the use or storage positions, and prevent the trailer suddenly moving from the use or storage position. If desired, one or more latches and/or other suitable means may be used to secure the trailer  114  in the collapsed or extended positions. 
     Advantageously, the adjustment assembly  186  may allow the trailer  114  to be quickly and easily moved between the use and storage positions. In addition, the adjustment assembly  186  may allow the trailer  114  to be automatically and/or mechanically moved between the use and storage positions. This may increase the potential users of the trailer because relatively little energy, effort and/or labor may be required to move the trailer  114  between the use and storage positions. 
     The adjustment assembly  186 , as shown in the accompanying figures, may include connecting members  188 , a track  190 , a shaft  192  and a movable carriage assembly or slider  194 . For example, as shown in  FIG. 43 , the connecting members  188  may be pivotally or otherwise movably connected to the central portions  174 ,  176  of the axle  170  using, for example, a suitable fastener or pivot pin, brackets or connectors  196 , and/or other suitable means. As shown in  FIG. 49 , the connecting members  188  may also be pivotally or otherwise movably connected to the carriage assembly  194 . For example, the connecting members  188  may be pivotally connected to a pivot pin  198  of the carriage assembly  194 . 
     As best seen in  FIG. 49 , the carriage assembly  194  may include a first portion  200  that is sized and configured to engage the track  190  and a second portion  202  that is sized and configured to be connected to the shaft  192 . For example, the first portion  200  of the carriage assembly  194  preferably slides relative to the track  190  and the second portion  202  is preferably threadably connected to the shaft  192 . 
     The shaft  192  may be connected to the arm  128  by a mount  204 . For example, the mount  204  may include a first portion  206  connected to the arm  128  and a second portion  208  connected to the shaft  192 . The shaft  192  is preferably inserted through an opening in the second portion  208  and the shaft is preferably held in a fixed position relative to the second portion using, for example, one or more plates  210 . The shaft  192  may also be connected to a connector  212 , which may be used to connect a crank, handle and/or other device that may be used to rotate the shaft. 
     Rotating the shaft  192  may be used to help adjust the position of the arm  128  and the axle  170  between the extended and collapsed positions. For example, as the shaft  192  is rotated in a first direction  214 , the threads of the shaft may engage the threads of the carriage assembly  194  to move the carriage assembly along the track  190  in a direction away from the mount  204 . As the carriage assembly  194  moves away from the mount  204 , the pin  198  may move the connecting members  188 , which may move the axle  170  and the arm  128  toward the collapsed position and away from the extended position. As the shaft  192  is rotated in an opposing second direction  216 , the threads of the shaft may engage the threads of the carriage assembly  194  to move the carriage assembly along the track  190  in a direction towards the mount  204 . As the carriage assembly  194  moves towards the mount  204 , the pin  198  may move the connecting members  188 , which may move the axle  170  and the arm  128  toward the extended position and away from the collapsed position. 
     As shown in  FIGS. 31-32 ,  37 - 39  and  43 - 45 , the axle  170  may be arranged in a generally straight configuration when the axle is in the extended position. For example, the portions  174 ,  176  of the axle  170  are preferably aligned along substantially the same plane, which may help provide a stronger, more stable and/or more secure axle. In addition, the axle  170  is preferably disposed in generally the same plane. As discussed above, it will be appreciated that the axle  170  need not having a generally straight configuration when the axle is in the extended position and the axle could be disposed at a forward or rearward angle, such as a forward angle that is between about one and five degrees or a rearward angle that is between about one and five degrees, if desired. 
     Desirably, unless a force is applied to the shaft  192 , the carriage assembly  194  remains in a generally fixed position and that may prevent the trailer  114 , the axle  170  and/or the arm  128  from moving between the use and storage positions. In greater detail, the carriage assembly  194  may be sized and configured to only move if the shaft  192  is rotated. Thus, if a rotational force is not applied to the shaft  192 , then the carriage assembly may remain in a fixed position and that may prevent the trailer  114 , the axle  170  and/or the arm  128  from moving between the use and storage positions. Therefore, the carriage assembly  194  may be used to lock the trailer  114 , the axle  170  and/or the arm  128  in the use and storage positions. Moreover, the carriage assembly  194  may be further sized and configured to lock the trailer  114 , the axle  170  and/or the arm  128  in a continuous or at least substantially continuous range of positions between and including the use and storage positions, if desired. It will be appreciated that the carriage assembly  194  may also be used to lock the trailer  114 , the axle  170  and/or the arm  128  in other suitable positions and other portions of the adjustment assembly  186 , if desired, may be used to lock the trailer, the axle and/or the arm in a desired position. 
     The trailer  114 , however, does not require the adjustment assembly  186  be used to move the trailer between the use and storage positions. For example, the wheel assembly  122  could be used to help move the trailer  114  between the collapsed and use positions. It will be appreciated that other suitable adjustment assemblies and/or structures or devices could be used to move the trailer between the use and storage positions. In particular, the trailer  114  may include other assemblies that are sized and configured to move the arm  128 , the frame  146 , the axle  170  and/or other portions of the trailer between the use and storage positions. 
     For example, as shown in  FIGS. 1-2 ,  7  and  13 - 14 , the trailer  10  may include an adjustment assembly  218  that includes a winch  220 . The adjustment assembly  218  may also include a cable coupled to the winch and to one or more portions of the trailer  10 . The cable may be coupled to these portions of the trailer  10  using, for example, brackets  222  that are sized and configured to receive a portion of the cable and/or guide the cable into the desired position. The adjustment assembly  218  may also include one or more pulleys that may be connected to any desired portions of the trailer  10 . Thus, the cable may be attached to various portions of the trailer  10  by the brackets  222  and pulleys, and the adjustment assembly  218  may be sized and configured to facilitate moving the trailer  10  from the use position to the storage position. 
     In greater detail, the winch  220  may be used to tighten the cable and move the trailer  10  from the use position to the collapsed position. In particular, the cable may be attached to various portions of the trailer  10  so that the cable may pull the sides of the trailer together when the winch is turned and the cable is tightened. Thus, the adjustment assembly  218  may be used to move the trailer  10  from the use to the storage position. 
     The trailer may also be moved between the use and collapsed positions by using other structures, such as the positioning apparatus  232  shown in  FIG. 50 . The positioning apparatus  232  may include two wheels  234  and two arms  236  that are interconnected by a frame. The arms  236  of the positioning apparatus  232  may be used to lift a wheel of the trailer away from a support surface, such as the floor of a garage, the ground, a driveway, etc. The positioning apparatus  232  may include a handle  237  that can be used may manipulate the arms  236  to lift the trailer&#39;s wheel. When the trailer&#39;s wheel is spaced apart from the support surface, the trailer may be more easily moved between the use and collapsed positions. In particular, when the trailer&#39;s wheel engages the support surface, the friction between the trailer&#39;s wheel and the support surface may resist or prevent the movement of the trailer between the use and collapsed positions. However, with the trailer&#39;s wheel spaced apart from the support surface, the wheels  234  of the positioning apparatus  232  may engage the support surface to allow the trailer to be readily moved between the use and collapsed positions. 
     It will be appreciated, therefore, that various suitable structures and apparatuses may be used to facilitate movement of the trailer between the use and storage positions. Advantageously, when the trailer is in the storage position, it may be much more compact and require much less storage space. This may allow the trailer to be used and stored in many different environments. For example, in the use position, the trailer may have a width of about five feet (1.52 meters) or about six feet (1.83 meters). When the trailer is in the collapsed position, however, the trailer may have a much smaller width. In particular, the trailer may have a width that is less than about 36 inches (91 centimeters) and/or less than about 30 inches (76 centimeters), which may allow the trailers to pass through many conventional doorways. It will be appreciated, however, that the trailer may have larger or smaller widths in the use and/or collapsed positions depending, for example, upon the particular configuration of the trailer. 
     When the trailer is in the collapsed position, the trailer preferably can be quickly and easily moved on its wheels to allow it to be positioned in the desired location. This may allow, for example, the user to quickly and easily store the trailer in a garage, shed and the like. The trailer, however, preferably cannot be towed or moved by a motor vehicle when the trailer is in the collapsed position. For example, the towing arm of the trailer (such as the arms  12 ,  128  discussed above) may be positioned to prevent towing of the trailer when the trailer is in the collapsed position. In particular, the towing arm may be positioned to make it difficult or impossible to use the towing arm. For example, the towing arm may be positioned in a retracted position behind the front end of the trailer. This may ensure that the trailer is towed only when the trailer is in the extended or use position. 
     As discussed above, the trailers can have different shapes, sizes, configurations and arrangements depending, for example, upon the intended use of the trailer. For example, as shown in  FIGS. 51-89 , another exemplary trailer  238  may include parts, features and aspects similar to those described above. The trailer  238 , however, may also include other parts, features and aspects. Advantageously, many of these different parts, features and aspects may be combined, interchanged and the like depending, for example, upon the intended use of the trailer. Thus, while the trailers may be described as having particular parts, features, aspects, sizes, shapes, configurations, arrangements and the like, it will be understood that any given trailer may have any suitable mixture of parts, features, aspects, sizes, shapes, configurations, arrangements and the like. 
     For example, as shown in  FIGS. 51-64 , the trailer  238  may include securing assemblies  240  that are sized and configured to removably secure one or more barriers to the trailer. In particular, the securing assemblies  240  may be used to selectively connect a front barrier  242  and a rear barrier  244  to front and rear portions of the trailer  238 , as best seen in  FIG. 54 . 
     In greater detail, as best seen in  FIGS. 55-60 , the securing assembly  240  may include an engaging member  246  that is sized and configured to contact or engage a portion of the barrier to help secure the barrier in a desired position. The engaging member  246  may help secure the barrier so that at least a portion of the barrier is disposed underneath a protrusion, extension or lip  248 , which may help better secure the barrier. As shown in  FIGS. 59-60 , the securing assembly  240  may also include a biasing member  250  that is sized and configured to bias the engaging member  246  to contact or engages the barrier. In particular, the securing assembly  240  may include a pin  252 , which may be connected to the engaging member  246  and the biasing member  250 , and the biasing member may bias the pin such that the engaging member is biased towards a position in which the engaging member contacts or engages the barrier. 
     If the front and rear barriers  242 ,  244  are selectively connected to the trailer  238 , then the securing assemblies  240  are preferably used to secure the barriers to the trailer  238 . In particular, two securing assemblies  240  may be used to secure the front barrier  242  to the trailer  238  and two securing assemblies may be used to secure the rear barrier  244  to the trailer. Specifically, one securing assembly may be used to secure each side of the front and rear barriers  242 ,  244  to the trailer  238 . In greater detail, as best seen in  FIGS. 55-58 , the trailer  238  may include left and right barriers  254 ,  256 , respectively, and these barriers may include the protrusion, extension or lip  248 . In addition, the left and right barriers  254 ,  256  may include slots  258  that are sized and configured to receive the ends of the front and rear barriers  242 ,  244 . Desirably, the engaging members  246  help secure the ends of the front and rear barriers  242 ,  244  within the slots  258 . Advantageously, the front and rear barriers  242 ,  244  may be interchangeably connected to the trailer  238 . 
     As shown in  FIG. 61 , the securing assembly  240  may include a handle  260 . The handle  260  may be connected to the pin  252  and the handle may be gripped to move the engaging member  246  between engaged and disengaged positions. Desirably, as shown in the accompanying figures, the engaging member  246  includes angled sides that allow the barriers  242 ,  244  to be connected to the trailer  238  without requiring the user to manipulate the securing assemblies  240 . In particular, the angled sides may allow the barriers  242 ,  244  to be inserted into the slots without the user manipulating the securing assemblies. When the barriers  242 ,  244  are in the desired positions, the engaging members  246  are biased into corresponding receiving portions in the barriers to secure the barriers in the desired positions. 
     The securing assemblies  240  may also help position the barriers  242 ,  244  in a generally vertical configuration, which may position at least a portion of the barrier underneath the protrusion, extension or lip  248 . For example, as best seen in  FIG. 64 , the barrier may be disposed at least partially underneath the lip  248  and that may help prevent the barrier from being inadvertently removed from the trailer  238 . In particular, the barrier may be initially inserted into the slot  258  at an angle. Once the barrier is in the desired position, the engaging member  246  of the securing assembly  240  may engage the barrier and the barrier may be disposed underneath the lip  248 , which may secure the barrier in the desired position. It will be appreciated that the securing assembly  240  does not have to position the barrier underneath the lip  248  and another structure, such as a spring or pin, may be used to bias the barrier underneath the lip. It will also be appreciated that any suitable number and arrangements of securing assemblies  240  may be used to secure the barriers to the trailer. Further, it will be appreciated that the securing assemblies  240  may have other suitable shapes, sizes, configurations and arrangements depending, for example, upon the size, shape and intended use of the trailer. 
     As shown in  FIGS. 65-66 , the rear portion of the trailer  238  and the front and rear barriers  242 ,  244  may include attachment members  262 ,  264  that are sized and configured to attach the barriers to the rear portion of the trailer for use as a ramp. Thus, the front and rear barriers  242 ,  244  may be used as sidewalls when the trailer  238  is being used and these same barriers may be used as ramps to facilitate loading and unloading of the trailer. It will be appreciated that the front and rear barriers  242 ,  244  do not have to be used as ramps and, if desired, the left and right barriers could be used as ramps. 
     In greater detail, the rear portion of the trailer  238  may include two outwardly extending flanges  262  that are sized and configured to receive corresponding outwardly extending flanges  264  of the front and rear barriers  242 ,  244 . The outwardly extending flanges  262 ,  264  may be connected by inserting the end of the flange  264  of the barrier into a receiving portion formed by the flange  262 . Thus, the attachment members  262 ,  264  may be sized and configured to be interchangeably connected to the barriers  242 ,  244  to the trailer  238 . The attachment members  262 ,  264  could also have other suitable shapes, sizes, configurations and arrangements depending, for example, upon the particular configuration of the trailer  238 . 
     While the trailer  238  is in the extended or use position, the trailer is preferably locked or secured in a fixed position. For example, as shown in  FIGS. 68-71 , the trailer  238  may include a latch  266  that is sized and configured to help secure the trailer in the extended position. The latch  266  may be connected to the frame and/or bed of the trailer  238 , such as a towing arm  268  of the trailer  238 . In particular, a portion of the latch  266  may be inserted into a receiving portion (such as a slot, opening or the like) in an elongated member  270 . In addition, an opening in the latch  266  may be aligned with one or more openings in the arm  268  and a fastener  272  may be inserted through the openings to retain the portion of the latch within the receiving portion of the member  270 . As shown in  FIGS. 70-71 , the fastener  272  may be secured using a ring, cotter pin or the like  274 . Significantly, this may help retain the trailer in the use position. In addition, this may help prevent the trailer  238  from being inadvertently moved from the use position to the collapsed position. Therefore, the latch  266  may be used to secure the trailer  238  in the use position. 
     When it is desired to move the trailer  238  from the use to the collapsed position, the latch  266  may be removed. As discussed above, various mechanisms may be used to facilitate movement of the trailer from the use to the collapsed position. In order to assist in moving the trailer  238  from the use to the collapsed position, a guide  276  may be used. For example, as shown in  FIG. 54 , the guide  276  may be connected to the arm  268 . Advantageously, if the arm  268  is moved rearwardly when the trailer  238  is being folded, then a portion of the trailer (such as the bed or frame) may contact the guide  276 . In particular, as shown in  FIG. 54 , the guide  276  may include a sloped portion  280  that is sized and configured to contact the frame or the bed of the trailer  238  when the arm  268  moves rearwardly. In particular, as best seen in  FIG. 67 , the elongated member  270  may contact the guide  276  as the trailer  238  is being folded, but other suitable portions of the bed or frame may contact the guide. Because the frame or bed of the trailer  238  must move upwardly to travel over the guide  276 , that may assist in the folding of the trailer. 
     Another suitable type of mechanism that may be used to facilitate movement of the trailer between the use and collapsed positions is shown in  FIGS. 73-78 . For example, the trailer  238  may include an adjustment assembly  282  that is sized and configured to adjust the position of the arm  268  and the axle  278 . The adjustment assembly  282  may include connecting members  284 , an upper track and a lower track  286 , a shaft  288  and a sliding mechanism such as a carriage assembly  290 . In particular, the connecting members  284  may be pivotally or movably connected to the axle  278  by fasteners, pins, brackets, connectors or the like. The connecting members  284  may also be pivotally or movably connected to the carriage assembly  290  by a fastener, pin, bracket, connector or the like. The carriage assembly  290  is preferably sized and configured to slide or move along the tracks  286 . The carriage assembly  290  is also preferably coupled to the shaft  288 . For example, the carriage assembly  290  and the shaft  288  may be threadably connected. 
     Additionally, the shaft  288  may be connected to the arm  268  using a mount  292  and the mount may be connected to the tracks  286 . Specifically, the shaft  288  may be inserted through an opening in the mount  292  and the position of the mount along the shaft may be generally fixed using any suitable means. The shaft  288  may also be connected to a crank, handle and/or other device that may be used to rotate the shaft. Rotating the shaft  288  may help move the arm  268  and the axle  278  between the extended and collapsed positions. For example, as the shaft  288  is rotated in a first direction, the threads of the shaft may engage the threads of the carriage assembly  290  to move the carriage assembly along the tracks  286  away from the mount  292 . As the carriage assembly  290  moves away from the mount  292 , the connecting members  284  may move the axle  278  and the arm  268  toward the collapsed position and away from the extended position. On the other hand, if the shaft  288  is rotated in an opposing second direction, the threads of the shaft may engage the threads of the carriage assembly  290  to move the carriage assembly along the tracks  286  towards the mount  292 . As the carriage assembly  290  moves towards the mount  292 , the connecting members  284  may move the axle  278  and the arm  268  toward the extended position and away from the collapsed position. Advantageously, the shaft  288  may be rotated by a number of different types of devices such as a hand crank  293  or a motor. If a motor is used, that may allow the trailer to be automatically opened and closed. 
     In addition to the trailer being capable of being quickly and easily moved between the use and collapsed positions, the trailer may provide improved handling, riding characteristics and the like. In particular, the trailer may provide a more stable and sure ride because, for example, the wheels may remain in the desired positions while the trailer is being used. For example, as shown in  FIGS. 79-80 , the trailer may include a suspension system  294  that is connected to the frame. In greater detail, the suspension system  294  may include a leaf spring that is connected to the support member  296  of the frame and the axle may be connected to the leaf spring. It will be appreciated that the suspension system  294  may have include other suitable components and the suspension system may have other appropriate arrangements and configurations depending, for example, upon the intended use of the trailer. 
     In further detail, the leaf spring of the suspension system  294  may be connected to the support member  296  by brackets  298 ,  300 ,  302 . In particular, the brackets  298 ,  302  may be generally U-shaped brackets that are connected to the support member  296  and the bracket  300 , which may also have a generally U-shaped configuration, may be connected to the bracket  298  and the suspension system  294 . The brackets  298 ,  302  are preferably connected to the support member  296  in a generally fixed position, and the bracket  300  is preferably pivotally or otherwise movably connected to the bracket  298  and the suspension system  294 . The bracket  302  may also be pivotally or otherwise movably connected to the suspension system  294 . 
     As shown in  FIGS. 79-85 , the brackets  298 ,  300 ,  302  may include a pair of flanges or walls that are generally aligned with opposing sides of the leaf spring of the suspension system  294 . Preferably, the flanges of the brackets  300 ,  302  are disposed proximate to and/or abut the sides of the leaf spring, which may help prevent the leaf spring from undesirably twisting while allowing the leaf spring to move up and down or deflect as desired. 
     As shown in  FIGS. 81-82  and  84 , reinforcing members  304 ,  306  may be connected to the brackets  298 ,  302 . The reinforcing members  304 ,  306  may be sized and configured to retain the flanges or walls of the brackets  298 ,  302  in a desired position. In addition, the reinforcing members  304 ,  306  may help the brackets  298 ,  302  from undesirably twisting or deforming. The brackets  298 ,  302  and the reinforcing members  304 ,  306  may comprise separate components that may be interconnected, such as by welding. It will be appreciated that the brackets  298 ,  302  and reinforcing members  304 ,  306  may be integrally formed as part of a unitary, one-piece structure if desired. The brackets  298 ,  300 ,  302  and the reinforcing members  304 ,  306  are preferably constructed from metal, but the brackets and reinforcing members may be constructed from other materials and/or have other suitable shapes, sizes configurations and arrangements. 
     As shown in  FIGS. 79-81  and  88 - 89 , the axle  278  and/or a wheel assembly, which may include a spindle and a hub, may be connected to the suspension system  294  by a connector  308 . For example, the connector  308  may include a first portion, such as a bracket  310 , that is sized and configured to be connected to the axle  278  and a second portion, such as a bracket  312 , that is sized and configured to be connected to the leaf spring of the suspension  294 . The bracket  310  is preferably pivotally or movably connected to the axle  278  and the bracket  312  is preferably connected to the leaf spring of the suspension system  294  in a fixed position. It will be appreciated that the connector  308  and the brackets  310 ,  312  may be connected to other portions of the axle and suspension system using other suitable structures. 
     The connector  308  may also include braces  314  that are connected to the brackets  310 ,  312 . The brackets  310 ,  312  and the braces  114  are preferably constructed from metal and the braces are preferably securely connected to the brackets by welding. It will be appreciated that the brackets  310 ,  312  and the braces  114  may be constructed from other suitable materials and may be connected by using fasteners, adhesives and the like, if desired. 
     As shown in  FIGS. 80-81 , the bracket  312  may include a receiving portion  316  that is sized and configured to receive a portion  318  of the leaf spring of the suspension system  294 . In particular, as best seen in  FIGS. 88-89 , the bracket  312  may include a generally U-shaped portion with a pair of flanges or walls  320 ,  322 . The leaf spring of the suspension system  294  may be secured in the desired position by U-bolts  324  and connecting members or plates  326 , as discussed in more detail below. 
     As shown in  FIGS. 79-81  and  88 - 89 , the flanges  320 ,  322  of the bracket  312  may be generally aligned with opposing sides of the leaf spring of the suspension system  294 . Preferably, the flanges  320 ,  322  are disposed proximate to and/or abut the sides of the leaf spring, which may help prevent the leaf spring from undesirably twisting while allowing the leaf spring to move up and down as desired. If desired, the flanges  320 ,  322  may be disposed generally parallel to each other and may be disposed proximate to and/or abut generally parallel opposing sides of the leaf spring. Of course, the flanges  320 ,  322  may be disposed in other relative positions and in other suitable locations depending, for example, upon the particular configuration of the bracket  312  or suspension system  294 . 
     The bracket  312  and the flanges  320 ,  322  preferably have an elongated shape that is substantially larger than the thickness of the axle  278 . For example, the bracket  312  and the flanges  320 ,  322  preferably have length that is at least two times the thickness of the axle  278 . In addition, the bracket  312  and the flanges  320 ,  322  may have a length that is at least three times the thickness of the axle  278 . The elongated shape of the bracket  312  and the flanges  320 ,  322  may advantageously help further prevent the leaf spring of the suspension system  294  from undesirably twisting. Of course, the bracket  312  and the flanges  320 ,  322  may have larger or smaller lengths if desired. In addition, the flanges  320 ,  322  may have different lengths and may have various suitable configurations and arrangements. 
     As shown in  FIG. 80 , the connector  308  may be secured to the leaf spring of the suspension system  294  by the U-shaped bolts  324  and the plates  326 . It will be appreciated, however, that the connector  308  may be secured to the suspension using any other suitable means. 
     As shown in  FIG. 90 , a trailer  328  may include a hitch coupler that is sized and configured to be connected to a trailer hitch. In particular, the arm of the trailer  328  may include, or be connected to, a hitch coupler  330  that is sized and configured to be coupled to the hitch of a towing vehicle. The hitch coupler  330  may be sized and configured to be coupled to a variety of differently sized and/or configured hitches, if desired. 
     The hitch coupler  330  may include a switch  332  that may be configured to move between an opened position and a closed position. When the switch  332  is in the opened position, the hitch coupler  330  may be coupled to the hitch of the towing vehicle. After the hitch coupler  330  is coupled to the hitch, the switch  332  may be closed to secure the hitch coupler to the hitch. If the switch  332  is closed before the hitch coupler  330  has been coupled to the hitch, however, the switch may prevent the hitch coupler from being coupled to the hitch. Thus, the switch  332  must first be opened to allow the hitch coupler  330  to be coupled to the hitch and the switch may then be closed to secure the hitch coupler to the hitch. It will be appreciated that the hitch coupler  330  and the switch  332  may have other suitable shapes, sizes, configurations and arrangements, but neither the hitch coupler nor the switch is required. 
     As shown in  FIGS. 90-91 , the trailer  328  may also include a coupling prevention device  334 , which may include a protrusion, extension or the like. The coupling prevention device  334  is sized and configured to prevent the switch  332  from moving from the closed position to the opened position when the trailer  328  is in the storage position shown in  FIG. 91 . Accordingly, this may help to prevent a user from moving the switch  332  to the opened position and attaching the trailer  328  to a towing vehicle when the trailer is in the storage position. It will also be appreciated that coupling prevention device  334  may have other suitable shapes, sizes, configurations and arrangements, but the prevention device is not required. 
     Yet another suitable type of mechanism that may be used to facilitate movement of a trailer between the use and collapsed positions is shown in  FIGS. 92-95 . In particular, as shown in  FIGS. 92-93 , a trailer  336  may include a towing arm  338  and an actuating mechanism. The actuating mechanism may include a crank  340 , which may be connected to and/or disposed proximate the front portion of the arm  338 . The crank  340  may also extend through an opening in the front portion of the arm. Desirably, this may allow the crank  340  to be readily used to help the actuating mechanism move the trailer  336  between a use position in which a bed and/or frame of the trailer is unfolded and a storage position in which the bed and/or frame of the trailer is folded. It will be appreciated, however, that the actuating mechanism may be connected to the front portion of the arm  338  and/or other portions of the arm and that the crank  340  may be disposed in other suitable locations. 
     The actuating mechanism may also include an adjustment assembly  342  that may sized and configured to adjust the position of the arm  338  and/or the position of an axle  344 . As shown in  FIG. 93 , the adjustment assembly  342  may include connecting members  346 , a shaft  348  and a carriage assembly  350 . 
     The connecting members  344  may be movably connected to the axle  344  and/or the carriage assembly  350 . For instance, the connecting members  344  may be pivotally connected to the axle  344  and the carriage assembly  350  using, for example, fasteners, pins, brackets, connectors or the like. 
     As shown in  FIGS. 94-95 , the shaft  348  may be coupled to the carriage assembly  350 . For example, the shaft  348  and the carriage assembly  350  may be threadably connected. In particular, the carriage assembly may include a tube  352  and an engaging member  354 , which may be disposed within the tube and may include one or more threads that may be threadably connected to one or more threads of the shaft  348 . 
     In addition, the shaft  348  may be connected to the arm  338  using a mount  356 . Specifically, the shaft  348  may be inserted through an opening in the mount  356  and the position of the mount along the shaft may be generally fixed using any suitable means. 
     The shaft  348  may also be connected to a crank, a handle and/or other device (such as the crank  340 ), which may be used to rotate the shaft. The crank  340  may be positioned to rotate in the same axis in which the shaft  348  rotates or in a different axis. For example, in some embodiments, a coupler may be used to interconnect the shaft  348  and the crank  340  to allow the crank to be positioned at an angle relative to the shaft (such as about a 90 degree angle, an oblique angle or any other suitable angle), as shown in  FIG. 92 . This may allow the crank  340  to rotate in a different axis than the axis in which the shaft rotates. The coupler may also be configured to allow the crank  340  to be generally aligned with the shaft  348 , which may allow the crank to rotate in the generally same axis in which the shaft rotates. Advantageously, the shaft  348  may be rotated by a number of different types of devices, such as the crank  340  or a motor. If a motor is used, that may allow the trailer to be automatically opened and closed, but this is not required. 
     Rotating the shaft  348  may help move the arm  338  and the axle  344  between extended and collapsed positions. For example, as the shaft  348  is rotated in a first direction, the threads of the shaft may engage the threads of the carriage assembly  350  to move the carriage assembly away from the mount  356 . As the carriage assembly  350  moves away from the mount  356 , the connecting members  346  may move the axle  344  and the arm  338  toward the extended position and away from the collapsed position. On the other hand, if the shaft  348  is rotated in an opposing second direction, the threads of the shaft may engage the threads of the carriage assembly  350  to move the carriage assembly towards the mount  356 . As the carriage assembly  350  moves towards the mount  356 , the connecting members  346  may move the axle  344  and the arm  338  toward the collapsed position and away from the extended position. 
     Desirably, unless a force is applied to the shaft  348 , the carriage assembly  350  remains in a generally fixed position, which may prevent the trailer  336 , the arm  338  and/or the axle  344  from moving between the use and storage positions. In greater detail, the carriage assembly  350  may be sized and configured to only move if the shaft  348  is rotated. Thus, if a rotational force is not applied to the shaft  348 , then the carriage assembly may remain in a fixed position and that may prevent the trailer  336 , the arm  338  and/or the axle  344  from moving between the use and storage positions. Therefore, the carriage assembly  350  may be used to lock the trailer  336 , the arm  338  and/or the axle  344  in the use and storage positions. Moreover, the carriage assembly  350  may be further sized and configured to lock the trailer  336 , the arm  338  and/or the axle  344  in a continuous or at least substantially continuous range of positions between and including the use and storage positions, if desired. It will be appreciated that the carriage assembly  350  may also be used to lock the trailer  336 , the arm  338  and/or the axle  344  in other suitable positions and other portions of the adjustment assembly  342 , if desired, may be used to lock the trailer, the arm and/or the axle in a desired position. 
     Portions of the mount  356  and the carriage assembly  350  may be slidably and/or telescopically coupled. For example, the mount  356  may include a tube  358 , and the tube  352  of the carriage assembly  350  may be slidably and/or telescopically coupled to the tube  358 . The tube  358  may be connected to the arm  338  using, for example, fasteners, pins, brackets, connectors, welds and/or any other suitable means. It will be appreciated, however, that the mount  356  and the carriage assembly  350  may have a variety of other suitable configurations, components, etc. 
     As shown in  FIG. 93 , the axle  344  may include a first center portion  360  and a second center portion  362  pivotally or otherwise movably connected to the first center portion. The first center portion  360  may include one or more elongated supports. The second center portion  362  include one or more elongated supports. It will be appreciated, however, that the axle  344  may have a variety of other suitable configurations, components, etc. 
     Advantageously, as discussed above, the trailer may be used to carry various items. After using the trailer, one may move the trailer from the use position to the storage position to allow the trailer to be more efficiently stored. When use of the trailer is again desired, one may move the trailer from the storage position back to the use position. 
     In addition, as discussed above and shown in the accompanying figures, the trailer may include barriers that may be selectively connected to and disconnected from the trailer. For example, the barriers may be selectively connected to the trailer in a generally vertical position to help prevent items from leaving the trailer. One or more of the barriers may also be disconnected from the trailer, such as the front and rear barriers, to allow the trailer to be moved from the use position to the storage position. After storing the trailer, the trailer may be moved back to the extended position and the barriers may be reconnected to the trailer. If desired, one or more of barriers may be used as a ramp to facilitate loading and unloading of the trailer. It will be appreciated, however, that the barriers that need not be selectively connectable or disconnectable from the trailer and that the trailer does not require any barriers. Moreover, it will be appreciated that the trailer need not be movable between the use and storage positions. 
     Other suitable aspects, features, configurations and arrangements that may be used in connection with the trailer are shown and described in U.S. patent application Ser. No. 11/609,316, filed Dec. 11, 2006, entitled TRAILER; U.S. patent application Ser. No. 11/609,317, filed Dec. 11, 2006, entitled TRAILER, now U.S. Pat. No. 7,452,00; U.S. patent application Ser. No. 11/609,318, filed Dec. 11, 2006, entitled TRAILER; U.S. patent application Ser. No. 11/609,319, filed Dec. 11, 2006, entitled TRAILER, now U.S. Pat. No. 7,475,901; U.S. patent application Ser. No. 11/609,327, entitled TRAILER, filed Dec. 11, 2006; U.S. patent application Ser. No. 11/609,323, entitled TRAILER, filed Dec. 11, 2006; and U.S. patent application Ser. No. 11/609,324, entitled TRAILER, filed Dec. 11, 2006. These applications and patents are incorporated by reference in their entireties. 
     Although this invention has been described in terms of certain preferred embodiments, other embodiments apparent to those of ordinary skill in the art are also within the scope of this invention. Accordingly, the scope of the invention is intended to be defined only by the claims which follow.