Abstract:
A rail for a trailer comprising an insert and rail body with a plurality of sides and an elongated slot, the slot being contained in one of the sides of the rail body and comprising a first and second surface, a side connecting the first and second surfaces and a lip attached to the second surface and opposing the side. The insert includes an elongated body sized to substantially fill and be contained within the slot, the rail body being made of a first material and the insert being made of a second material, the second material having a higher yield strength and higher tensile strength than the first material.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention is directed towards a structural side rail for a dumping vehicle and a method to manufacture the rail. The present invention can be used on a tipper trailer, dump trailer or any other type of trailer or cargo box mounted on the back of a truck which needs a lightweight and strong structural member. 
     2. Prior Art 
     Tipper trailers are used to transport cargo, such as garbage or other materials, behind trucks or other vehicles. The cargo is dumped from a tipper trailer by moving the trailer onto a platform, detaching the truck, and then tilting the platform so that the front end of the tipper trailer is raised above the rear end, and the cargo slides out the rear end by the force of gravity. Unlike a dump trailer, the platform provides the tilting force to raise the trailer between the loading and unloading positions, whereas a dump trailer has a mechanism built into the trailer which can tip the trailer. 
     The sidewalls of tipper trailers are typically constructed from sheets of aluminum that are welded together along their sides so that a series of vertical seams are produced. The vertical seams provide wear points where a weakness can occur as the cargo slides over the sidewalls during dumping of a tipper trailer. 
     In the prior art, vertical rails have been placed over the seams to protect the seams from wear and also to provide support for the sidewalls. If the vertical rails are placed in the interior of a tipper trailer, they interfere with the discharge of the cargo during dumping. Typically, therefore, vertical rails are placed on the exterior of a tipper trailer so that the interior is smooth. Placing rails on the exterior of a tipper trailer results in a reduction of the interior volume available for cargo, since the overall width of the tipper trailer is limited by traffic laws. In addition, numerous vertical seams and vertical rails are required in the construction of a tipper trailer. Because the lengths of the sidewalls are typically many times their height, and the expense of welding numerous sheets of metal together and welding numerous rails onto the sidewalls significantly increases the cost of manufacturing a tipper trailer using vertical rails. 
     Also, in the prior art, the floor of a tipper trailer is constructed so that it is at a minimum height in order to accommodate the hitch (or fifth wheel) to the truck or other vehicle used to pull the tipper trailer. The floor is typically parallel to the ground throughout. The overall height, width, and length of the tipper trailer are all limited by traffic laws. Therefore, the height of the floor affects the interior volume and capacity of the tipper trailer for cargo. 
     Tipper trailers with horizontal ribs or rails were introduced as an improvement on tipper trailers constructed with vertical ribs. 
     In an effort to maximize the internal volume of the tipper trailer while minimizing the weight, it is possible to use a set of internal horizontal rails which add rigidity to the sidewalls of the trailer while providing a wear and tear resistance structure covering the seam and part of the sidewall of the tipper trailer. This also facilitates sliding of the cargo from the interior during dumping. One drawback of using the horizontal rails is that due to their long span, they have a tendency to flex outward when the tipper trailer is loaded. It is possible for the sidewalls of a tipper trailer constructed using horizontal rails to flex outward up to eleven inches when fully loaded. The horizontal rails were typically made from a single piece of extruded aluminum. Thus the horizontal rails must be made of an aluminum extrusion with very thick sidewalls. A center crossover brace can also be attached to the top center of the sidewalls in order to minimize the deflection of the sidewalls when the tipper trailer is loaded. However, the center crossover brace interfere with top loading the tipper trailer. 
     It is an object of the present invention is to reduce the thickness of the sidewalls of the horizontal rails while increasing the strength and rigidity of these rails. 
     It is a further object and purpose of the present invention to minimize the amount of weight of the horizontal rails. 
     It is yet a further object and purpose of the present invention to maximize the strength and rigidity of the tipper trailer side rails. 
     It is yet a further object and purpose of this invention to create a horizontal rail for a trailer which is sturdy enough that a center crossover brace is not required. 
     Other objects and further scope of the applicability of the present invention will become apparent from the detailed description to follow, taken in conjunction with the accompanying drawings wherein like parts are designated by like reference numerals. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention is an improved rail for a tipper trailer. Tipper trailers are primarily used for transporting and dumping of materials such as garbage. The rail is constructed of an extruded piece of metal typically aluminum, although other metals or materials could be used. The rail has a slot running the length of it. A second piece, the insert, made of stronger material such as AR400 or 7005 aluminum, although other metals or materials could be used, is then inserted in the slot. The insert does not need to run the entire length of the rail but should run a substantial portion of the length of the rail and should be located in the center portion of the rail. The insert can be held in place by a number of apparatuses including a second piece of extruded aluminum used as a clip or a weld or combination of the two. If the extruded rail is aluminum and the insert is steel, the insert can be coated with a powder coating or galvanized in order to prevent corrosion inherent when steel and aluminum are in direct contact with each other. Under certain circumstances the slot can be coated with an adhesive prior to the insert being placed in the slot. The adhesive prevents the insert from coming in direct contact with the slot thus eliminating the need to coat the insert. The adhesive also provides a sufficient bond between the slot and the insert thus eliminating the need to use a retaining body such as a rod, clip or block welded to the interior of the rail, clip and/or weld to hold the insert in place. Also once the insert is in place the interior of the rail can be filled with a urethane foam to prevent air from coming in contact with the steel and aluminum interface in order to further prevent the possibility of corrosion. The rail is then welded into place, thus, sealing the interior of the rail from the atmosphere. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a tipper trailer mounted on a platform and tilted so that the cargo is emptied from it. 
     FIG. 2 is a cut-away perspective drawing of a tipper trailer constructed with horizontal internal ribs and a center brace without using the present invention. 
     FIG. 3 is a perspective drawing of a tipper trailer with horizontal rails using the present invention. 
     FIG. 4 is a cross-sectional view of FIG. 3 showing the construction of the top horizontal rail and intermediate horizontal rail along with the left side wall. 
     FIG. 5 is a cross-sectional view of a top horizontal rail incorporating the present invention wherein the insert is held in place by a rod and a weld. 
     FIG. 6 is a cross-sectional view of a top horizontal rail incorporating the present invention wherein the insert is held in place by an extruded metal clip and a weld. 
     FIG. 7 is a close up of the clip and weld holding the insert in FIG.  6 . 
     FIG. 8 is a cross-sectional view of an intermediate horizontal rail with the insert being held in place by a bar in a weld. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     While the making and using of various embodiments of the present invention are discussed in detail below, it should be appreciated that the present invention provides for inventive concepts capable of being embodied in a variety of specific contexts. The specific embodiments discussed herein are merely illustrative of specific manners in which to make and use the invention and are not to be interpreted as limiting the scope of the instant invention. 
     The claims and the specification describe the invention presented and the terms that are employed in the claims draw their meaning from the use of such terms in the specification. The same terms employed in the prior art may be broader in meaning than specifically employed herein. Whenever there is a question between the broader definition of such terms used in the prior art and the more specific use of the terms herein, the more specific meaning is meant. 
     While the invention has been described with a certain degree of particularity, it is clear that many changes may be made in the details of construction and the arrangement of components without departing from the spirit and scope of this disclosure. It is understood that the invention is not limited to the embodiments set forth herein for purposes of exemplification, but is to be limited only by the scope of the attached claim or claims, including the full range of equivalency to which each element thereof is entitled. 
     FIG. 1 is a perspective view of a tipper trailer  10  with horizontal rails on a tipping platform  30  being emptied. The tipper trailer  10  has a front end  12 , a right side wall  14 , a left side wall  16 , a floor  18 , and a rear tailgate  20  with external ribs  22  mounted on hinges  24 . One of the intermediate horizontal ribs  26  can also be seen. It also has a seam  28  running horizontally the length of the tipper trailer  10  on both sides, the right side wall  14  and the left side wall  16 . This is where the sheets of aluminum are joined together to form the right side wall  14 . The corresponding seam  28  found on the left side wall  16  cannot be seen in this figure. The tipper platform  30  is pivotally connected to the base  32 . It is tilted by the hydraulic telescopic cylinders  34  mounted to the platform  30  and base  32 . 
     While the tipper trailer  10  is sitting on the platform  30  it is supported by the front supports  36  and a plurality of wheels  38 . The tipper trailer  10  is held on the platform  30  by a pair of floor rails  39  which run the length of the platform  30  and are found on either side of the tires  20 . There are also one or more braces  40  mounted on the platform  30  which helps retain the tipper trailer  10  on the platform  30  while it is being tilted. 
     Once the tipper trailer  10  is in the tilted position, the cargo  42  slides out the rear tailgate  20  and into a pile or pit where it is then moved for further processing. Various types of tipper platforms are known and the platform  30  does not form a part of the invention. 
     FIG. 2 is a cut-away perspective drawing of a tipper trailer  10  constructed without using the present invention. The tipper trailer  10  has a right and left side wall  14  and  16 , a front end  12 , a floor  18  and a center crossover brace  43 . The right and left side wall  14  and  16  both have two intermediate horizontal rails  26  and a top horizontal rail  46 . The center crossover brace  43  is attached to the top horizontal rails  46  to add rigidity to the right and left side walls  14  and  16  and to prevent them from flexing outward when the tipper trailer  10  is fully loaded. The front end  12  of the tipper trailer  10  has two vertical rails  44  to provide added strength for the front end  12 . Although it is not shown in FIG. 2, the four intermediate rails  26  and two top rails  46  are each made from a single piece of extruded aluminum. 
     Both the right and left side wall  14  and  16  have a plurality of shims or transition plates  48  located near the rear of the tipper trailer  10 . The shims  48  help funnel the cargo  42  out the rear of the tipper trailer  10  when it is being emptied. 
     FIG. 3 is a perspective drawing of a tipper trailer  10  with the intermediate and top horizontal rails  26  and  46  using the teachings of the present invention. As can be seen in the drawing, due to the increased strength of the improved intermediate and top horizontal rails  26  and  46 , only a top horizontal rib  46  and an intermediate horizontal rib  26  are required. Also due to the increased strength of the improved rails, a center crossover brace  43  as shown in FIG. 2 is not required to prevent the left and right sidewalls  14  and  16  from bowing outward when the tipper trailer  10  is fully loaded. A pair of shims  48  are located on the left side wall  16  above and below the intermediate horizontal rails  26 . The shims  48  help funnel the cargo out the rear of the tipper trailer  10  when it is tipped. The right side Wall  14  has a corresponding pair of shims  48  which are not shown in FIG.  3 . The seam  28  is shown running down both the right side wall  14  and the left side wall  16 . The intermediate horizontal rail  26  is located to cover the seam  28  on the inside of the tipper trailer  10  in order to avoid wear on the seam  28 . 
     FIG. 4 is a cross-sectional end view of the left side wall  16  with its top horizontal rail  46  and the intermediate horizontal rail  26 . The left side wall  16  is constructed of two sheets of metal, typically aluminum, which are connected together with a weld at the seam  28 . It should be noted that other materials could be used for the side wall other than aluminum. In its preferred embodiment, the top horizontal rail  46  is initially mounted onto the left side wall  16  using a clip portion  50  of the top horizontal rail  46 . Once the top horizontal rail  46  is in place, it is secured in place by welds  52  and  54 . The intermediate horizontal rail  26  is placed over the seam  28  and welded into place by welds  56  and  58 . 
     FIG. 5 is a cross-sectional close up view of the top horizontal rail  46 . The top horizontal rail  46  has a slot  60 . The slot  60  has a first surface  61 , a second surface  63 , a third surface  65  connecting the first and second surfaces  61  and  63 , a lip  62  running along the second surface  63  and teeth  64  running along the first surface  61 . The insert  66  is made of a material with a higher tensile strength and a higher yield strength than the material of the top horizontal rail  46 . If the material of the top horizontal rail  46  is zaluminum and the insert  66  is made of a steel, the insert  66  can be coated with a powder coating or galvanized in order to prevent direct contact between the aluminum and the steel. The coating will help eliminate the possibility of corrosion inherent when aluminum and steel are in direct contact. Other possible preferred materials for the insert  66  are higher strength aluminum alloy, polycarbon or higher strength steel alloy. 
     In order to assemble the top horizontal rail  46  and the insert  66 , the insert  66  is placed in the slot  60  prior to the top horizontal rail  46  being mounted on the left side wall  16 . The insert  66  is placed in the slot  60  by inserting the insert  66  through the opening  68  with the leading edge  70  of the insert  66  going in first. The insert is then rotated so that the leading edge  70  is inserted into the slot  60  and behind the lip  62 . The insert is then rotated further so that the trailing edge  72  is brought into contact with the teeth  64 . The slot  60  and the insert  66  are sized so that there is an interference fit between the trailing edge  72  and the teeth  64 . When the leading edge  72  comes into initial contact with the teeth  64 , force is applied along the trailing edge  72  to force the trailing edge  72  into the slot  60 . This creates the interference fit between the trailing edge  72  and the teeth  64 . Once the trailing edge  72  is in place, a rod  74  is placed next to the trailing edge  72  and the teeth  64 . The rod  74  is held in place by the weld  76 . It should be noted that the rod  74  is made of a material that is compatible for welding to the material which the top horizontal rail  46  is constructed of. Once the insert  66  is in place, the interior  78  can be filled with a urethane foam to reduce the amount of oxygen in the interior  78  and to further reduce the possibility of corrosion between the top horizontal rail  46  and the insert  66  in the event they are made of incompatible materials, such as aluminum and steel respectively. The assembled top horizontal rail  46  is then clipped onto the left side wall  16  and welded into place. It should be noted that the top horizontal rail on the right side wall is constructed and assembled in a similar manner. 
     FIG. 6 is a cross-sectional end view of a top horizontal rail  46  as shown in FIG. 5, however, the insert  66  found in FIG. 6 is held in place by a clip  80  and a weld  82 . 
     FIG. 7 shows a close up view of the clip  80  shown in FIG.  6 . The clip  80  and the weld  82  can be used in lieu of the rod  74  and weld  76  as shown in FIG.  5 . 
     FIG. 8 is a cross-sectional end view of the intermediate horizontal rib  46  shown in FIG.  4 . The intermediate horizontal rail  26  has an slot  84  with a first surface  85 , a second surface  87 , and a third surface  89  connecting the first and second surfaces  85  and  87 . The slot  84  has a lip  86  running along the second surface  87 . The slot  84  has a groove  98  running along the first surface  85 . The insert  88  is held in the slot  84  by the lip  86  running along the leading edge  90  of the insert  88  and the block  92  and weld  94  running along the trailing edge  96  of the insert  88 . As on the top horizontal rail  46 , the insert  88  of the intermediate horizontal rail  26  is typically made of a material with a higher tensile strength and higher yield strength than the material of the intermediate horizontal rib  26 . In the event that the intermediate horizontal rib  26  and insert  88  are made of incompatible materials, such as aluminum and steel respectively, the insert  88  can be coated with a powdered coating or galvanized in order to minimize the possibility of corrosion inherent with aluminum and steel in direct contact with one another. 
     In order to assemble the insert  88  and intermediate horizontal rib  26 , the leading edge  90  of the insert  88  is passed through the open side  98  of the intermediate horizontal rib  26 . The leading edge  90  is then placed in the slot  84  behind the lip  86 . The trailing edge  96  is then rotated until it is in the slot  84 . Force can be applied as necessary along the trailing edge  96  of the insert  88  in order to force it into the slot  84 . Once the insert  88  is in the slot  84  the block  92  is inserted in the groove  98  running along the trailing edge  96  of the insert  88 . The block  92  is then held in place by the weld  94 . The interior  100  of the intermediate horizontal rib  26  can be filled with urethane foam in order to minimize the presence of oxygen within the intermediate horizontal rib  26  in an effort to minimize the possibility of corrosion. The fully assembled intermediate horizontal rib  26  is then welded into place on the left side wall  16 . It should be noted that the intermediate horizontal rib  26  found on the right side wall  14  would be constructed in a similar manner. 
     In an alternative embodiment of the present invention, under certain circumstances the slot  60  of the top horizontal rail  46  shown in FIG.  5  and the slot  84  of the intermediate horizontal rail  26  shown in FIG. 8 can be coated with any one of a number of adhesive commercially available prior to the insert  66  or  88  being place into the slot  60  or  84 . The adhesive prevents the insert  66  or  88  from coming into direct contact with the slot  60  or  84  thus eliminating the need to coat the insert  66  or  88 . The adhesive also provides a sufficient bond between the slot  60  or  84  and the insert  66  or  88  thus eliminating the need to use a retaining body such as the rod  74 , the clip  80  or the block  92  or having to weld the retaining bodies into place with their related welds  76 ,  82  and  94  respectively. 
     While this invention has been described to illustrative embodiments, this description is not to be construed in a limiting sense. Various modifications and combinations of the illustrative embodiments as well as other embodiments will be apparent to those skilled in the art upon referencing this disclosure. It is therefore intended that this disclosure encompass any such modifications or embodiments.