# Patent

## Title
Trailer construction using vertical extruded aluminum panels

## Abstract

A smooth side trailer body or body structure comprised of a plurality of extruded panel members positioned adjacent one another. The extruded panels are arranged perpendicular to the floor of a trailer. The panels are held to the floor by a bottom rail. A top rail portion may be used to hold the panels together to form a more rigid wall.

## Background
This application is a continuation of application Ser. No. 10/745,248, filed Dec. 23, 2003, now U.S. Pat. No. 6,929,311 which is a continuation of application Ser. No. 10/177,728, filed Jun. 21, 2002, now U.S. Pat. No. 6,669,271, which claims priority from and benefit of the filing date of U.S. application Ser. No. 60/300,232, filed Jun. 22, 2001. Application Ser. No. 10/745,248 and Ser. No. 10/177,728 and Ser. No. 60/300,232 are hereby incorporated by reference.


TECHNICAL FIELD
The present invention is directed to a smooth side trailer and body structure having walls formed of interlocking extruded aluminum panels and the method of making the same. Panels are aligned vertically adjacent to one another, with at least one female receiving portion in one panel engaging at least one male portion an adjacent panel. Adjacent panels form smooth side walls of a trailer.
BACKGROUND
Dump trailers, dump bodies, tipper trailers and walking floor trailers (bulk commodity trailers/bodies), traditionally have been produced in various lengths and capacities and consist generally of a chassis formed principally of one or more I-beams and a plurality of cross frame members joining the same with ground engaging wheel assemblies located under one end of the chassis and retractable support gear situated inwardly of the other end. A dump body comprises a floor structure incorporating longitudinal and cross frame members and a floor thereon with side walls and a front end wall secured thereto. The dump body is pivotally mounted on the chassis adjacent to the rear end thereof and a hoist, usually hydraulically actuated, is positioned between the front end of the dump body to elevate the same. While a variety of metallic materials have been employed to fabricate dump bodies, light weight and high strength metals, such as aluminum and various alloys thereof (hereafter collectively “Aluminum”), have become the favored manufacturing stock because they make possible production of trailers/bodies having low “empty weight” and optimum payload potential.
Aluminum floor, side wall and other components have been produced for dump bodies; however, such components have largely taken the form of either rolled sheet metal and/or a variety of extruded members which were solid throughout. Additionally, such dump body components have typically been joined to one another by known arc welding techniques that not only require highly skilled welding personnel and considerable quantities of energy and consumable materials, but also are less than ideally suited for Aluminum components. In addition, the walls formed by these materials and processes in order to be structurally sound did not form smooth walls. The walls typically utilize reinforcing members at spaced apart intervals along the length of the wall, forming a serrated appearance, which increases wind resistance. High wind resistance and heavy weight increases travel time and fuel consumption in use of the trailer or body.
Thus, a need exists for a trailer/body structure that, in addition to being structurally sufficient to accommodate desired loads and uses, like those sheet metal and/or extruded solid forms now commonly employed, are even lighter in weight and have smooth walls. In addition, it would be beneficial to provide such a trailer which does not require substantial amounts of support structures welded to the inside walls which take up valuable capacity. It would also be desirable to form the trailer or body to have increased capacity for use in handling larger volumes of materials where the above desired characteristics would be even more important.
SUMMARY
The present invention provides a body structure wherein the side walls of the trailer body or body are comprised of a plurality of lightweight, high strength extruded metal components which provide smooth outer walls of the trailer body. These and other advantages are provided by a trailer comprising a top rail, a bottom rail, and a plurality of hollow, extruded wall panels positioned vertically adjacent one another wherein the plurality of hollow, extruded wall panels are secured at one end to the top rail and at the opposite end to the bottom rail. Each wall panel comprises an inside wall and an outside wall connected to each other by a first end wall and a second end wall. The first end wall includes a groove that extends along the length of the panel between the top rail and the bottom rail and the second end wall includes a projection that extends along the length of the panel between the top rail and the bottom rail such that the projection of the second wall matingly engages the first wall of an adjacent wall panel. The outside walls of the plurality of wall panels form a smooth exterior trailer wall surface.
These and other advantages are also provided by a method of constructing a trailer comprising the steps of:

    
    
        providing a bottom rail having a wall engaging portion and a floor engaging portion;
        attaching the bottom rail floor engaging portion to a floor of the trailer;
        providing a plurality of extruded hollow wall panels wherein each wall panel comprises an inside wall and an outside wall connected to each other by a first end wall and a second end wall and the first end wall includes a groove that extends along the length of the panel and the second end wall includes a projection which that extends along the length of the panel;
        attaching the plurality of wall panels to each other by positioning the projection of the second end wall of a wall panel into the groove of the first end wall of an adjacent wall panel;
        inserting and securing the plurality of interconnected wall panels into the wall engaging portion of the bottom rail; and
        attaching a top rail over the plurality of interconnected wall panels.
    
    





BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross sectional view of prior art trailer floor and walls.
FIG. 2 is a top view of a portion of a smooth wall formed by extruded panels in accordance with the present invention.
FIG. 3 is a cross sectional view of a bottom rail of a trailer in accordance with the present invention, which connects the extruded panels to the floor of the trailer.
FIG. 4 is a cross sectional view of a top rail in the present invention.
FIG. 5 is a cross sectional view of a trailer floor and walls in accordance with the present invention.
FIG. 6 is a side view of a first embodiment of a smooth side tipper trailer in accordance with the present invention.
FIG. 7 is a side view of a second embodiment of a smooth side tipper trailer in accordance with the present invention.
FIG. 8 is a side view of a third embodiment of a smooth side tipper trailer in accordance with the present invention.



DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described herein in reference to the attached figures. It should be understood that although specific embodiments are shown in the drawings and described herein, variations of these embodiments are clearly within the scope of the present invention.
In the following description, “inside” refers to the surface of the body structure walls facing the cargo holding area of the body; “outside” refers to the direction away from the cargo holding area of the body.
FIG. 1 illustrates a cross section of a prior art trailer 100. Prior art bodies are comprised of a floor 102. Side walls 104 were welded to the floor 102 at a bottom portion and then supported by a brace 108, which was welded to both the floor 102 and the wall 104. A top rail 106 was positioned over the top portion of the wall and welded thereto. The prior art walls were generally in the form of either rolled sheet metal and/or a variety of extruded members which were solid throughout. The components were typically joined to one another by arc welding techniques which not only require highly skilled welding personnel and considerable quantities of energy and consumable materials, but also are less than ideally suited for Aluminum components.
The body components of the present invention are shown in FIGS. 2 through 8. FIG. 6 shows a typical tipper-type trailer. Tipper trailers are constructed of a chassis (not shown), having one or several spaced parallel I-beams (not shown) with cross frame members therebetween (not shown) and ground engaging wheel assemblies 66 below the back end of the chassis. The trailer further comprises a body structure which includes a floor member or assembly 50 positioned on a plurality of spaced cross frame members (not shown). The floor member 50 supports the side walls, which are comprised of a plurality of adjacent extruded panels 10. The back end of the tipper trailer is designated 64. The back end of the trailer 64 may have an opening through which cargo material in the trailer body will move by gravity when the tipper trailer is elevated. In the alternative, tipper trailers may be configured to be lifted by a tipping machine and inverted such that material will move out of the trailer through the back end 64 or another opening. Those skilled in the art will observe that an opening at the back end of the tipper body is usually closed with a pivotal tail gate and that the front end or bulkhead of the trailer body 58 is provided with the usual front wall typically constructed of a sheet material to join the side walls making an enclosed space. It should be understood that various trailer constructions maybe used with the inventive wall and assembly configurations described herein.
In the present invention, the walls of the trailer are made from a plurality of extruded panels 10 arranged vertically or horizontally and adjacent to one another. A top view of two extruded panels 10 positioned adjacent to one another is shown in FIG. 2. The extruded panels are preferably made of extruded aluminum or another metal, which provides sufficient durability to withstand carrying of cargo as well as contact with extreme environmental elements. The length of the panels is variable depending on the desired height of the trailer walls and body configuration. One of the only limitations on the size of the panel is the capacity of an extruding machine used to make the panels. In one embodiment of the present invention, the hollow spaces in the wall panels 10 are filled with an insulating material such as foam or fiber-glass insulation. The insulating material is used to increase the strength of the panels and/or to provide some hot or cold thermal insulation for the body's cargo. In the alternative, solid extruded aluminum wall panels are within the scope of the present invention.
As shown in FIG. 2, each panel 10 is typically hollow and has an inside wall 12, an outside wall 14, and two end walls 16 and 18. Each panel also has intermediate walls 20 which connect the inside wall 12 and outside wall 14 between the two end walls 16 and 18. The intermediate walls 20 also serve to reinforce the inside 12 and outside 14 walls. The number of intermediate walls can be varied based on the width of the extruded panels 10 and the need for additional reinforcement in the panel 10. The wall panels 10 may also comprise reinforcing ribs 21 shown in FIG. 2 projecting from the inside wall 12 toward the outside wall 14 or vice versa. The reinforcing ribs 21 provide additional strength and rigidity to the wall panels 10.
A first end wall 16 is equipped with a groove 26 that extends along the length of the panel between the top rail 60 and bottom rail 40 of trailer (FIG. 5). A second end wall is equipped with a ridge or flange 24. The flange 24 also extends along the length of the panel. The flange 24 and groove 26 correspond to one another and the groove is slightly larger than the ridge so that the ridge of one panel 10 can be inserted into the groove 26 of another panel when the panels are mounted adjacent one another. As shown in FIG. 2, groove 26 and ridge 24 are offset towards the outside wall 14. Seals are created at the flange and groove connection between the two panels. In addition, the flange and groove are positioned on the sides of the extruded panels such that when the panels are positioned adjacent to one another and fit together, the side walls of the body structure is smooth.
It is contemplated by the present invention that the panels may lock together simply by the action of the flange of one panel engaging the groove of a second panel. Alternatively, it should be understood that adhesives may be placed on the sides of the panels between two adjacent panels where the flange and groove engage or the seam between panels can be welded. Other suitable methods of connecting panels to one another or combinations thereof are contemplated. It is also contemplated by the present invention that no flange or groove be present on the panels and that the panels are substantially smooth on all sides. The adjacent panels could be placed adjacent to one another within the bottom rail portion (described in relation to FIG. 3) and secured into place by frame members at the front 58 and rear 64 of the body and/or the top rail member (described in relation to FIG. 4). Furthermore, the smooth panels could be secured together by adhesive and/or welding between adjacent end walls of two panels.
The panels are secured to the floor by the bottom rail apparatus shown in FIGS. 3 and 5 generally designated 40. The bottom rail comprises a wall engaging portion 36, a floor engaging portion 38, and a reinforcement portion 42. The width of the wall engaging region 36 is slightly larger than the width of extruded panels 10 so that extruded panels 10 fit tightly into the wall engaging portion. The floor engaging portion 38 has a lower member 48 which extends below the floor and may be welded thereto. The floor engaging portion 38 also has an upper member 46 which extends a short distance along the surface of the floor 50. The bottom rail also has a reinforcement portion 42 which extends upwards at an angle approximately 45° from the floor. The reinforcement portion 42, as shown in FIG. 5, engages the side wall panels when mounted with the floor engaging portion 38 to form a triangle between the wall 10 and the floor 50. The reinforcement portion also has a flat end portion 44 which is connected, such as by welding or adhesive, to the extruded wall panels 10. The bottom rail 40 may be welded to the floor 50 or wall panels 10 at various places. The reinforcement portion 42 is integral to the bottom rail to provide structural integrity in association with the wall as formed from the plurality of wall panels 10, and yet greatly simplifies manufacturing and reduces labor and materials in the construction. The provision of the reinforcing portion 42 may also allow thinner wall panels 10 to be used while providing the desired structural characteristics, but it should be evident that the characteristics of the wall panels and/or bottom rail 40 could be modified to yield desired structural integrity without the use of the reinforcement portion 42, and thus this portion would not be necessary.
Prior to engagement with the bottom rail 40, the wall panels 10 formed into a wall assembly typically will have some flexibility due to its construction form a plurality of individual panels 10. Once the extruded panels 10 are positioned adjacent one another in the bottom rail 40, a substantially rigid wall is formed. To further rigidify the wall assembly and to cap the top of the wall, a top rail member 60 as shown in FIG. 4 may be positioned over the top of the extruded panels to further secure the panels together to form a rigid wall. The top rail member 60 is positioned over the top of the extruded panels as shown in FIG. 5, with ends 32 and 34 being connected, such as by welding or adhesive to the respective outer and inner surfaces of the wall panels 10. As shown in FIGS. 2 and 5, inside end 34 extends lower than outside end 32. The top rail member 60 adds additional structural rigidity to the wall assembly and along with the bottom rail 40 tie the walls into the front bulkhead and rear tailgate as well as the floor of the body to form a rigid body having the desired structural characteristics. In the prior art, due to the characteristics of the walls, it many times would be necessary to provide reinforcing tie bars at spaced intervals along the length of the trailer, which extend between the walls. With the wall construction according to the invention, the use of such tie bars may be eliminated, thereby allowing access to the interior of the trailer through the entire top opening along the length of the body.
The panel arrangement also allows for different body configurations to be constructed. As shown in FIGS. 7 and 8, the volume of the body can be increased by varying the shape of the floor. In FIG. 7, shorter panels are used at a front portion of the body in front of the landing gear member 74. The floor to the rear of the landing gear is dropped to lower creating a larger volume body. Longer vertical extruded panels are used at the portion along the length of the floor where the floor has been lowered.
As shown in FIG. 8, various length panels can be used with another type of variable height floor. Longer panels must be used in the portion of the body wall where the distance between floor and the desired height of the body is the greatest. This creates a body having a greater volume than the body shown in FIGS. 6 and 7, limited only by the width of the extruded vertical panels and the capacity of the trailer floor, axles or landing gear.
As previously discussed and in reference to FIGS. 2 through 8, the method of constructing a trailer comprises the following steps. First, providing a bottom rail 40 having a wall engaging portion 36 and a floor engaging portion 38. Secondly, attaching the floor engaging portion 38 of the bottom rail to a floor 50 of the trailer. Next, providing a plurality of extruded hollow wall panels 20 wherein each wall panel comprises an inside wall and an outside wall connected to each other by a first end wall and a second end wall and the first end wall includes a groove 26 that extends along the length of the panel and the second end wall includes a projection 24 which that extends along the length of the panel. Another step involves attaching the plurality of wall panels 20 to each other by positioning the projection of the second end wall of a wall panel into the groove of the first end wall of an adjacent wall panel. This step can be supplemented by applying an adhesive between the second end wall of a wall panel and the first end wall of an adjacent wall panel and/or welding a seam on an interior seam between the plurality of wall panels. Next, inserting and securing the plurality of interconnected wall panels 20 into the wall engaging portion 36 of the bottom rail. Prior to the last step, the method may include an optional step of filling the plurality of extruded hollow wall panels with an insulating material. Lastly, attaching a top rail 30 over the plurality of interconnected wall panels.
Although the present invention has been described above in detail, the same is by way of illustration and example only and is not to be taken as a limitation on the present invention. Accordingly, the scope and content of the present invention are to be defined only by the terms of the appended claims.

## Claims

1. A trailer comprising:
first and second spaced-apart trailer side walls each comprising a plurality of vertically extending monolithic hollow extruded aluminum wall panels positioned adjacent one another, wherein each of the plurality of aluminum panels includes: (i) a lower end; (ii) an upper end spaced vertically above said lower end; (iii) an inside wall; and, (iv) an outside wall spaced apart from said inside wall; (v) first and second spaced-apart end walls that interconnect the spaced-apart inside and outside walls and that respectively define a projection and a groove that extend between said upper and lower ends of the panel, wherein each of the first and second trailer side walls is constructed by said plurality of extruded aluminum wall panels having their respective projections mated with the respective grooves of adjacent ones of said plurality of wall panels, and wherein the plurality of wall panels of the first trailer sidewall define a smooth exterior surface of said first trailer sidewall, and wherein the plurality of wall panels of the second trailer sidewall define a smooth exterior surface of said second trailer sidewall;
first and second horizontally extending top rails connected respectively to the first and second side walls, wherein the first top rail is connected to and captures the upper end of each hollow extruded vertical wall panel of the first sidewall, with each hollow extruded vertical wall panel of the first side wall captured between inside and outside ends of the first top rail, and wherein the second top rail is connected to and captures the upper end of each hollow extruded vertical wall panel of the second side wall, with each hollow extruded vertical wall panel of the second side wall captured between inside and outside ends of the second top rail; and
first and second horizontally extending bottom rails connected respectively to the first and second side walls, said first and second bottom rails each comprising a floor engaging portion and a wall engaging portion, wherein the first bottom rail is connected to and captures the lower end of each hollow extruded vertical wall panel of the first side wall in the wall engaging portion of the first bottom rail, and wherein the second bottom rail is connected to and captures the lower end of each hollow extruded vertical wall panel of the second side wall in the wall engaging portion of the second bottom rail; and,
a floor that is perpendicular to the first and second sidewalls and that extends between and interconnects the first and second bottom rails, wherein the floor is received in and extends between the floor engaging portion of the first bottom rail and the floor engaging portion of the second bottom rail and wherein the floor engaging portions of the first and second bottom rails comprise respective lower members that extend beneath and support the floor.

2. The trailer according to claim 1, wherein the top rail first wall engaging flange comprises a right angle flange engaging both a top surface of the wall panels and the outside wall of the wall panels.