Abstract:
A combination trailer and ramp assembly ( 20 ) is provided. The combination trailer and ramp assembly includes a trailer ( 24 ) having a floor assembly ( 30 ) including an upper surface, a lower surface, and a length. The trailer further includes first and second sidewalls ( 32 ) extending from the floor assembly, and a side door ( 34 ) located in at least one of the first and second sidewalls. The combination trailer and ramp assembly further includes a ramp assembly ( 26 ) slidably disposed on the lower surface of the trailer for reciprocating movements between a stowed position, where the ramp assembly is stowed underneath the floor assembly, and a deployed position, where the ramp assembly extends along an axis substantially parallel to the length of the floor assembly to permit access to the side door of the trailer.

Description:
FIELD OF THE INVENTION 
     The present application relates generally to loading ramps for vehicles and, more particularly, to a side-mounted ramp for a trailer. 
     BACKGROUND OF THE INVENTION 
     Both long and short-haul vans and semi-trucks are frequently required to make a delivery in narrow alleyways between buildings. For reasons of economics, it is often advantageous for these vehicles to carry both dry bulk goods, which are not required to be refrigerated, and perishables which, on the other hand, require at least some degree of refrigeration. To accommodate these deliveries, it is well known to use a dual temperature trailer having, as the name suggests, two temperature independent sections. One section of such trailers, typically the forward section, is refrigerated, while the other is not. For thermal efficiency, as well as practical considerations, such trailers have a side door providing access into the refrigerated compartment of the trailer. 
     To gain access into the side door, dual temperature trailers may include a variety of assemblies, such as a ladder located beneath the side door or a ramp that extends normal to the length of the trailer. Although such apparatuses are effective at providing access into and out of the trailer, they are not without their problems. 
     First, with trailers that utilize a ladder to gain access into and out of the trailer, the ladder often provides more of a hindrance to the efficient loading and unloading of the trailer. Specifically, in order to unload or load the trailer, the goods must be placed on the trailer bed while the delivery person climbs into or out of the trailer on the ladder. Although the delivery person may attempt to gain access into and out of the trailer by carrying the goods on their shoulder while climbing up and down the ladder, such an attempt is undesirable due to the inherent safety risks. 
     With respect to trailers that include a ramp extending normally to the length of the trailer, such systems are ineffective in numerous respects. In this regard, such trailers require a fairly large amount of space to extend the ramp at an appropriate angle which would make access into and out of the trailer on the ramp feasible. Further, in certain circumstances, maneuvering the trailer into an unloading area wide enough to accommodate the extension of such ramp assemblies is not possible. This is especially true in inner city deliveries where deliveries are often made in the narrow alleyways between buildings. Thus, for such deliveries, the ramp assembly is not extendable and, therefore, access into and out of the trailer is difficult at best. 
     Thus, there exists a need for a ramp assembly that provides access into and out of a side door of a trailer where the ramp assembly is lightweight and does not require a large area for extension. 
     SUMMARY OF THE INVENTION 
     One embodiment of the present invention includes a trailer and ramp assembly. The trailer includes a floor assembly having an upper surface, a lower surface, a length, and first and second sidewalls extending from the floor assembly. The trailer also includes a side door located in at least one of the first and second sidewalls. The ramp assembly is slidably disposed on the lower surface of the trailer for reciprocating movement between a stowed position, where the ramp assembly is stored underneath the floor assembly, and a deployed position, where the ramp assembly extends along an axis extending substantially parallel to the length of the floor assembly to permit access to the side door of the trailer. 
     In one aspect of this embodiment, the combination trailer and ramp assembly further includes a bracket assembly extending between the ramp assembly and the lower surface of the trailer. A portion of the bracket assembly is mounted to the lower surface of the trailer by a guide assembly for reciprocating movement of the ramp assembly between the stowed and deployed positions. In yet another aspect of this embodiment, the combination trailer and ramp assembly further includes a lock mechanism fastened to the bracket assembly for selectively locking the ramp assembly into the stowed position. 
     In still yet another embodiment of the present invention, the ramp assembly includes first and second platforms each having first and second-ends longitudinally spaced by a walking section having a length, and a hinge assembly. The hinge assembly extends between a portion of the bracket assembly and the second ends of the second platform at a support point for swinging movement of the second platform between a stored position, where the first and second platforms are stacked on each other, and an extended position, where the first end of the second platform is located on a ground surface. 
     In another embodiment of the present invention, the bracket assembly includes a retractable first support assembly positioned adjacent the support point and is selectively deployable into an extended position, wherein the retractable first support assembly is positioned for supporting engagement with the ramp assembly substantially near the support point. 
     In still yet another embodiment, the combination trailer and ramp assembly further includes a retractable second support assembly positioned substantially near the side door and is reciprocally coupled to the trailer for movement between an extended position, wherein the retractable second support assembly is positioned for supporting engagement with the second end of the first platform, and a retracted position. The retractable second support assembly includes a stationary support member fixed to a portion of the trailer and an arm telescopically received within a stationary support member. The arm is selectively deployable between an extended position, where the arm engages and supports the second end of the first platform, and a retracted position. When the arm is in the extended position, at least a portion of loads associated with the first platform is transferred to the stationary support member. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing aspects and many of the attendant advantages of this invention will become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein: 
     FIG. 1 is a perspective view of a combination trailer and side ramp assembly formed in accordance with one embodiment of the present invention; 
     FIG. 2 is a partially exploded view of a combination trailer and side ramp assembly formed in accordance with one embodiment of the present invention showing the ramp assembly exploded away from the trailer for clarity; 
     FIG. 3 is a perspective view of a portion of the ramp assembly formed in accordance with one embodiment of the present invention; 
     FIG. 4 is a partially exploded view of a portion of the bracket assembly of a combination trailer and side ramp assembly formed in accordance with one embodiment of the present invention; 
     FIG. 5 is a perspective view of a combination trailer and side ramp assembly formed in accordance with one embodiment of the present invention and showing the side ramp assembly in a stowed position; 
     FIG. 6 is a perspective view of a combination trailer and side ramp assembly formed in accordance with one embodiment of the present invention and showing the ramp assembly in a folded but unstowed position; and 
     FIG. 7 is a perspective view of a combination trailer and side ramp assembly formed in accordance with one embodiment of the present invention and showing the side ramp assembly in a partially deployed position. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 illustrates a combination trailer and ramp assembly  20  formed in accordance with one embodiment of the present invention. The combination trailer and ramp assembly  20  is illustrated as a semi-truck  22  and includes a trailer  24  and a ramp assembly  26 . Although the combination trailer and ramp assembly  20  is illustrated as a semi-truck  22 , the invention is not so limited. Accordingly, it should be apparent to one of ordinary skill that such a ramp assembly may be coupled to other types of vehicles, such as a delivery van, and therefore, such vehicles are also within the scope of the present invention. 
     The well-known trailer  24  includes a floor assembly  30 , sidewalls  32  extending upwardly from the floor assembly  30 , and a door  34  located in one of the sidewalls  32 . Although not necessary, the trailer  24  is suitably a dual temperature trailer that includes at least two internal compartments (not shown) that are temperature independent of each other. Such trailers are known to transport both perishables that require refrigeration, as well as bulk goods that do not require refrigeration. Again, although such a trailer is preferred, other types of trailers, such as a full refrigerated trailer or a dry van, are also within the scope of the present invention. 
     As seen best by referring to FIGS. 1 and 2, the ramp assembly  26  will now be described in greater detail. The ramp assembly  26  includes first and second platforms  40   a  and  40   b  and a bracket assembly  42 . Each platform  40   a  and  40   b  is identically configured and, therefore, only one platform will be described in greater detail. However, it should be apparent that the description of one platform is applicable to the other. The platform  40   a  may be suitably formed from a lightweight, high-strength material, such as aluminum. Each platform includes an elongated walking section  44 , suitably formed from a grate-like material, longitudinally framed by first and second side rails  46   a  and  46   b . The longitudinally spaced ends of the walking platform  44  define first and second ends  48   a  and  48   b.    
     Opposing ends  48   b  and  48   a  of the first and second platforms  40   a  and  40   b  may be suitably attached by a well-known hinge assembly  50 . In one embodiment, the hinge assembly  50  includes first and second attachment flanges  52   a  and  52   b , first and second attachment arms  54   a  and  54   b , and a shoulder flange  56 . The first and second attachment flanges  52   a  and  52   b  are suitably formed on a portion of the bracket assembly  42 , as described in greater detail below, and are positioned for pinned attachment to the first and second attachment arms  54   a  and  54   b  extending from the first end  48   a  of the second platform  40   b.    
     For ease of illustration, only the second attachment arm  54   b  is illustrated in FIG.  2 . However, it should be apparent that an identically configured attachment arm  54   a  is suitably positioned on the first end  48   a  of the second platform  40   b . The shoulder flange  56  is suitably formed with a portion of the bracket assembly  42  and is positioned for arresting engagement with the second end  48   b  of the first platform  40   a , as described in greater detail below. 
     Referring now to FIGS. 2 and 3, the bracket assembly  42  will now be described in greater detail. The bracket assembly  42  includes first and second retractable support assemblies  60  and  62  and a stowage arm assembly  64 . The first retractable support assembly  60  and stowage arm assembly  64  are substantially identically configured and, therefore, only the first retractable support assembly  60  will be described in greater detail. However, it should be apparent that the description of the first retractable support assembly  60  is applicable to the stowage arm assembly  64 . 
     As may be seen best by referring to FIG. 3, the first retractable support assembly  60  is suitably formed from a high strength material, such as steel, and includes a housing  66  and an arm  68  slidably received within the housing  66 . The housing  66  is suitably rectangular in configuration and is fastened to the floor assembly  30  of the trailer  24  by first and second flanges  70   a  and  70   b . One end of each flange  70   a  and  70   b  is attached to the housing  66 , while the other end of each flange  70   a  and  70   b  is suitably affixed to the floor assembly  30  in a manner well known in the art, such as by welding or rivets. 
     Attached to the housing  66  are a plurality of wheel guides  72   a - 72   c . Each wheel guide  72   a - 72   c  includes a roller bearing  74  rotatably attached to the housing  66  by spaced parallel flanges  76   a  and  76   b  extending normally to a surface of the housing  66 . The roller bearings  74  extend partially into the interior of the housing  66  through a correspondingly located hole extending through a side of the housing  66 . The roller bearings  74  are positioned for sliding engagement with the arm  68  to assist in easy retraction and extension of the arm  68  from within the housing  66 . The arm  68  is suitably rectangular in configuration and includes first and second stop flanges  78   a  and  78   b  attached to the longitudinal ends of the arm  68 . 
     As may be best seen by referring to FIG. 3, the first retractable support assembly  60  also includes a lock assembly  80 . The lock assembly  80  includes a lock arm  82  and a U-shaped detent  84 . The lock arm  82  is rotatably attached to the arm  68  by a pair of brackets  86   a  and  86   b . The lock arm  82  is suitably a rod-like member having one end curved in an L-shape manner to form a handle  88 , while the other end of the lock arm  82  is similarly bent to form a lock bar  90 . 
     The lock bar  90  is positioned on the arm  68  to be selectively received within the detent  84  to lock the first retractable support assembly  60  into a retracted position. In this regard, the first retractable support assembly  60  is illustrated in the retracted position, wherein the arm  68  is received within the housing  66  and stowed completely beneath the floor assembly  30  of the trailer  24 . Further, the lock bar  90  of the lock assembly  80  is received within the U-shaped detent  84 , thereby preventing unintentional deployment of the first retractable support assembly  60  during operation of the vehicle. 
     To unlock the arm  68  from within the housing  66 , the operator would simply rotate the lock arm  82  in the direction indicated by the arrow  92  thereby removing the lock bar  90  from within the detent  84 . The arm  68  is then slidably pulled out from within the housing  66  into an extended position and in the direction as indicated by the arrow  94 . This position is illustrated in phantom in FIG.  3 . 
     Referring now to FIG. 4, the second retractable support assembly  62  will now be described in greater detail. The second retractable support assembly  62  is suitably formed from a high strength material, such as steel, and is disposed within the floor assembly  30  near the side door  34 . The second retractable support assembly  62  includes a tubular housing  96  and a retractable arm  98 . The tubular housing  96  is affixed within a cavity  100  extending normally to the longitudinal direction of the trailer  24 . 
     The retractable arm  98  is slidably received within the housing  96  and may be reciprocated between a stowed position, where the arm  98  is received within the housing  96 , and an extended position, wherein the arm  98  is pulled out from within the housing  96 . In the extended position, the retractable arm  98  is simply supported by the housing  96 , such that at least a portion of the load associated with the first platform  48  is transferred to the housing  96  and, therefore, to the floor assembly  30 . The retractable arm  98  may be locked within the housing  96  by a latch plate (not shown) adapted to seal the arm  98  within the housing  96  when the second retractable support assembly  62  is in the stowed position. 
     Operation of the combination trailer and ramp assembly  20  may be best understood by referring to FIGS. 5-7. As seen in FIG. 5, the ramp assembly  26  is in the stowed position and is disposed underneath the floor assembly  30  of the trailer  24 . To deploy the ramp assembly  26 , the operator extends the retractable arm  98  of the second retractable support assembly  62  located near the side door  34 . Next, the operator unlocks the lock assembly  80  of the first retractable support assembly  60 , as well as the lock assembly of the stowage arm assembly  64 . Then, the operator grabs on to the side rails  46   a  of the ramp assembly  26  and pulls the ramp assembly  26  out from underneath the floor assembly  30  of the trailer  24 . This position is illustrated in FIG.  6 . Sliding motion of the ramp assembly  26  is facilitated by the roller bearings  74 , as described above. 
     As seen best in FIG. 7, the first platform  40   a  is slid from the top of the second platform  40   b  until the first end  48   a  of the first platform  40   a  is received on and supported by the extended retractable arm  98  of the second retractable support assembly  62 . The first platform  40   a  is pulled forward until the second end  48   b  engages the shoulder flange  56  positioned on the arm  68  of the first retractable support assembly  60 . Next, the second end  48   b  of the second platform  40   b  is lifted upward and the arm  68  of the stowage arm assembly  64  is slid back into the housing  66 . Finally, the second end  48   b  of the second platform  40   b  is lowered to the ground surface. In this position, the ramp assembly  26  extends in a direction parallel to the longitudinal direction of the trailer  24  and is simply supported by the ground surface, thereby allowing the ramp assembly to be deployable on both level and unlevel surfaces. 
     The combination trailer and side ramp assembly  20  formed in accordance with one embodiment of the present invention has several advantages over currently available assemblies. As a non-limiting example, because the ramp assembly extends parallel to the length of the trailer, such a vehicle does not require a large spotting area to load or unload the vehicle. This is especially advantageous for inner city deliveries. Further, there is no need for a level surface for the efficient operation of the ramp assembly because one end of the ramp assembly is adapted to be simply supported by the ground surface. Another example is time savings. This advantage is illustrated by the fact that the ramp assembly may be deployed and stowed in a matter of seconds. This has freed up time available for backhauling of product, reduced overtime, and improved on-time delivery. Also, because the ramp assembly is easy to deploy, as well as stow, the operator will tend to use it instead of by-passing the ramp and transferring goods by lifting them into and out of the trailer. This reduces the risk of injury, as well as reduces the risk of damaged goods. Thus, such a combination has multiple advantages over existing systems. 
     While the preferred embodiment of the invention has been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention.