Patent Publication Number: US-8967673-B2

Title: Trailer having an enclosed tank area with integral toolbox

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention is related generally to bulk tankers and bulk tank trailers. More particularly, the present invention is related to systems and methods of storing tools and equipment associated with bulk tankers and bulk tank trailers. Specifically, the present invention is related to bulk tankers and bulk trailers having an enclosed tank area with an integral toolbox. 
     2. Background Information 
     Bulk tankers and bulk tank trailers are among the many types of vehicles used for hauling materials over highways and the like. They typically have several hoppers or cones which facilitate the discharge of the bulk material from within the tank into a discharge line through which air is pumped to discharge the material to a rear end of the trailer. Valve assemblies are located at the bottom of the hoppers whereby the hoppers may be opened or closed to respectively allow the flow of the bulk particulate material from the hoppers into the discharge pipe or to cut off this flow. An additional aeration line or heated blow pipe typically runs along one side of the hoppers to provide air for stirring the bulk material within the hoppers to facilitate the downward movement of the material within the hoppers. During operation, this blow pipe typically becomes hot enough to cause burn injuries to truck drivers who are unloading the bulk material. Other pipes branching off of this aeration line may also become hot enough to cause burn injuries. The occurrence of such burn injuries is increased due to the fact that the handles for operating the discharge valves for the hoppers require the truck driver or other operator to stoop down below the hot blow pipe and maneuver adjacent any of these heated pipes. Maintaining the hoppers, their discharge valves and performing other maintenance on bulk tankers often requires the use of a variety of tools. Therefore, there exists a need for a better way to access and store tools associated with bulk tankers and tanker trailers. 
     BRIEF SUMMARY OF THE INVENTION 
     The preferred embodiment of the invention includes a trailer having an integrated chamber with a toolbox. The trailer includes a bulk tank with at least a first hopper and a second hopper. The first hopper has a first discharge port and the second hopper has a second discharge port. A discharge pipe is connected to the first and second discharge ports. A storage box is formed integral and between the first hopper and the second hopper to define a storage chamber. A door is mounted on the storage box having open and close positions for respectively providing access to and blocking access to the storage chamber. 
     In one configuration of the preferred embodiment, a portion of the first hopper forms a portion of a first wall of the storage chamber and a portion of the second hopper forms a portion of a second wall of the storage chamber. Similarly, a first portion of the storage chamber can be below the first hopper and a second portion of the storage chamber can be directly below the second hopper. 
     The door covers an opening to the storage chamber. The door includes a door perimeter wall projecting outward from a rear surface of the door toward the storage chamber when the door is in the closed position. The storage chamber includes a chamber perimeter wall outwardly projecting from a perimeter around the opening toward the door. When the door is in the closed position, the door perimeter wall is adjacent and outside the chamber perimeter wall so that the front of the door and the door perimeter wall cover the opening and the chamber perimeter wall and the opening. A waterproof sealer can be attached to either the door perimeter wall or the chamber perimeter wall. The waterproof seal can then create a waterproof seal between the door perimeter wall and the chamber perimeter wall when the door is in the closed position. A hinge can be used to mount the door to the storage box and a lock can be mounted on the door for locking the door in the closed position. 
     Another configuration of the preferred embodiment includes a bulk trailer with a frame and a set of ground-engaging wheels mounted to the frame. A bulk tank comprising two or more hoppers is attached to the frame. An enclosure is integrally formed with one of the hoppers. A toolbox with an interior chamber is secured to the frame within the enclosure. The toolbox can be directly in front of a hopper or directly behind a hopper. 
     In some configurations, one of the hoppers is a first hopper that is the frontmost hopper and the toolbox is directly in front of the front hopper. The bulk tank can have a rear end and a top. A ladder can be located adjacent the rear end of the bulk tank extending downwardly from the top of the bulk tank. When the first hopper serves as a rearmost hopper, the toolbox can be directly behind the first hopper. The bulk tank can also have a front end. The ladder can be adjacent the front end of the bulk tank and extend downwardly from the top of the bulk tank. 
     In other configurations of the preferred embodiment, there may be other useful features. For example, a portion of the toolbox can be below the first hopper and/or a second hopper. The toolbox can additionally be between the first hopper and the second hopper. A door can be mounted on the toolbox adapted to move between a closed position to prevent access to the interior chamber of toolbox or an open position allowing access to the interior chamber of toolbox. The bulk trailer can include a sidewall extending between the first hopper and the second hopper with an access opening formed in the sidewall for accessing the toolbox. A lock can be included on the door to prevent unauthorized access to the toolbox. 
    
    
     
       BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS 
       One or more preferred embodiments that illustrate the best mode(s) are set forth in the drawings and in the following description. The appended claims particularly and distinctly point out and set forth the invention. 
       The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate various example methods, and other example embodiments of various aspects of the invention. It will be appreciated that the illustrated element boundaries (e.g., boxes, groups of boxes, or other shapes) in the figures represent one example of the boundaries. One of ordinary skill in the art will appreciate that in some examples one element may be designed as multiple elements or that multiple elements may be designed as one element. In some examples, an element shown as an internal component of another element may be implemented as an external component and vice versa. Furthermore, elements may not be drawn to scale. 
         FIG. 1  is a side elevational view of the bulk tanker and bulk tank trailer of the preferred embodiment of the present invention. 
         FIG. 2  is an enlarged sectional view through the axial center of one of the hoppers and associated structures taken from the left side. 
         FIG. 3  is an enlarged sectional view through the longitudinal center of one of the valve control handles, handle extensions and the hopper shown in  FIG. 2  taken from the front. 
         FIG. 4  is an enlarged front elevational view of the trailer taken forward of the frontmost hopper with the front deck, front enclosure and portions of the air pipe assembly removed for clarity. 
         FIG. 5  is an example illustration of the integrated toolbox located between two hoppers on a hopper trailer with its door in a closed position. 
         FIG. 6  is an example cross-sectional view of the door of the integrated toolbox. 
         FIG. 7  is an example illustration of the integrated toolbox located between two hoppers on a hopper trailer with its door in an open position. 
         FIG. 8  is an example illustration of the integrated toolbox located on the front of a hopper trailer with its door in a closed position. 
         FIG. 9  is an example illustration of the integrated toolbox located on the rear of a hopper trailer with its door in a closed position. 
     
    
    
     Similar numbers refer to similar parts throughout the drawings. 
     DETAILED DESCRIPTION OF THE INVENTION 
     A bulk tank trailer of the preferred embodiment of the present invention is shown generally at  1  in  FIG. 1 . A trailer  1  is a towed vehicle which is typically towed by a towing vehicle in the form of an on-road tractor  2  whereby trailer  1  and the tractor  2  form a tractor trailer rig in the form of a bulk tanker. More particularly, the front of the trailer  1  is pivotally hitched to the rear of tractor  2  via a hitch  4  such as a fifth wheel hitch or the like. Trailer  1  has a front  6  and a back  8  defining therebetween a longitudinal direction. Trailer  1  further has a top  10  and a bottom  12 . 
     Trailer  1  further includes a left side  14  and a right side  16  ( FIG. 4 ) defining therebetween an axial direction. Left side  14  is typically the driver side whereas right side  16  is typically the passenger side although this may be the opposite in various countries. For clarity, an explanation of some terms used herein is provided. The trailer  1  has an axial center line CL ( FIG. 4 ) or center plane which is a vertical longitudinally extending plane cutting through the center of the trailer midway between the left side  14  and right side  16  thereof. As is readily evident from the Figures, various components are axially offset or spaced from the center plane. The present description of the trailer  1  will make reference to certain components, sides, surfaces, points and the like as being inboard or outboard of one another. As will be appreciated, such terms typically relate to the left or right halves of the trailer whereby with regard to the left half (left of central plane CL), a first point which is outboard of a second point is further to the left than the second point or further outboard than the second point in a first or left outboard direction, and thus the second point is inboard of or to the right of the first point. Thus, within the left half, the first point is further outboard or further from the center plane than is the second point. Likewise, with regard to the right half (right of central plane CL), a third point which is outboard of a fourth point is further to the right than the fourth point or further outboard than the fourth point in a second or right outboard direction, and thus the fourth point is inboard of or to the left of the third point. Thus, within the right half, the third point is further outboard or further from the center plane than is the fourth point. 
     With primary reference to  FIG. 1 , trailer  1  has a rigid frame  18  including a substantially horizontal longitudinally elongated main drop or lower deck  20  and a substantially horizontal front raised or higher deck  22  which is adjacent front  6 . Deck  20  has left and right vertical outboard sides  19  ( FIG. 6 ) which face away from and are parallel to center plane CL. Sides  19  are longitudinally elongated, extending from the front of deck  20  to the back of deck  20 . Ground engaging wheels  21  are rotatably mounted on frame  18  about a horizontal axially extending axis Y ( FIG. 4 ) via a suitable suspension assembly adjacent back  8 . Some axles can include pairs of wheels on each end of an axle so that there are inner wheels  33  adjacent outer wheels  35 . Deck  20  extends from adjacent the back of front deck  22  to adjacent wheels  21  and back end  8  of trailer  1 . Tractor  2  also has ground engaging wheels  21 , some of which are driven by the tractor&#39;s engine in the standard fashion. 
     Trailer  1  further includes landing gear  23  generally adjacent front  6 . Landing gear  23  may be of any suitable type known in the art and is configured to move between a lowered position (dashed lines in  FIG. 4 ) in contact with the ground for supporting the front of trailer  1  when disconnected from tractor  2  and a raised position ( FIG. 1  and solid lines in  FIG. 4 ) out of contact with the ground when trailer  1  is hitched to tractor  2  for over the road travel. More particularly, landing gear  23  includes left and right vertical legs  25  and a ground engaging foot  29  secured to the bottom of leg  25 . Particularly, each leg  25  is a telescoping leg which includes an upper leg section and a lower leg section which is telescopically mounted on the upper section to move vertically between the raised and lowered positions along with foot  29 . The upper section of the left leg  25  is rigidly secured to the left outboard side  19  of deck  20  and extends axially outboard and downwardly therefrom. Likewise, the top section of the right leg  25  is rigidly attached to the outboard right side  19  of deck  20  and extends axially in the opposite outboard direction therefrom and downwardly therefrom. 
     Trailer  1  further includes a bulk tank  24  having left and right outboard sides  31  ( FIG. 4 ) which face away from the axial center plane CL. Tank  24  defines an interior bulk storage chamber  26  for carrying dry particulate material  27  in bulk. Material  27  may be, for example, sand, plastic beads, pellets or any other solid particulate material typically carried in bulk tank trailers. Bulk tank  24  typically includes several hoppers or cones  28 . In the exemplary embodiment, hoppers  28  include three hoppers  28 A-C wherein hopper  28 A is the frontmost hopper and hopper  28 C is the rearmost hopper. Hopper  28 B is directly behind hopper  28 A, while hopper  28 C is directly behind hoppers  28 A and B. Although trailer  1  includes three hoppers, such trailers are also typically configured with two or four hoppers, and possibly more. Center plane CL ( FIG. 4 ) cuts through the axial center of tank  24  midway between outboard sides  31  and through the axial center of each of hoppers  28 . A plurality of hopper feed ports  30 , including openable and closable lids, are mounted on top of tank  24  respectively directly above hoppers  28  whereby there are typically the same number of ports  30  as hoppers  28 . Ports  30  may be opened in order to receive bulk material  27  there through to fill chamber  26  to a desired level. The lids of the ports may be closed to secure the material therein and keep moisture and other material out of the interior chamber and to provide a generally airtight seal. 
     Trailer  1  further includes a front enclosure  32  which is rigidly secured to and extends upwardly from front deck  22  to the top  10  of bulk tank  24 . Enclosure  32  is also rigidly secured to and extends forward from the front of hopper  28 A to adjacent front end  6 . Trailer  1  further includes a rear enclosure  34  which is rigidly secured to and extends upwardly from the top of rear deck  20  adjacent the back end  8  to the top rear of tank  24 . Rear enclosure  34  is also rigidly secured to and extends rearwardly from the back end of hopper  28 C. Trailer  1  can further include a built-in ladder  36  which is formed integrally with rear enclosure  34  and provided with suitable handrails. Trailer  1  further includes two lower enclosures  38 A and  38 B, each of which is between an adjacent pair of the hoppers  28 . Each lower enclosure  38  is rigidly secured to deck  20  and extends upwardly therefrom to a rigid connection to the rear of one hopper  28  and the front of the adjacent hopper  28 . Deck  20  extends from longitudinally adjacent the bottom of front hopper  28 A and forward of hoppers  28 B and  28 C to longitudinally adjacent and rearward of hoppers  28 B and  28 C. Deck  20  also extends from forward of lower enclosures  38 A and  38 B to rearward thereof, and from forward of rear enclosure  34  to rearward thereof. 
     Trailer  1  can further include an air piping assembly  40  which is used to facilitate the discharge of material  27  from within interior chamber  26 . A valve assembly  42  is secured to the bottom of each hopper  28  and includes a valve which is operated by a substantially straight rigid valve control handle  44 . Handle  44  is rotatable between an open position and a closed position. In the exemplary embodiment, the frontmost valve assembly  42 , handle  44  and the bottom of hopper  28 A are forward of landing gear  23  whereas the other valve assemblies  42 , handles  44 , and bottoms of the other hoppers  28 B,  28 C are rearward of landing gear  23 . Center plane CL ( FIG. 4 ) cuts through the axial center of each of valve assemblies  42 . 
     Hoppers  28  are now described in greater detail with primary reference to  FIGS. 2 and 3 . Each hopper  28  includes a conical or frustoconical sidewall  48  which tapers or angles downwardly and radially inwardly and has frustoconical arcuate inner and outer surfaces  50  and  52 . Thus, the front portion of sidewall  48  and the inner and outer surfaces  50  and  52  thereof taper downwardly and rearwardly, the rear portion of sidewall  48  and its inner and outer surfaces  50  and  52  angle or taper downwardly and forward, the left portion of sidewall  48  and its inner and outer surfaces  50  and  52  angle or taper downwardly and rightward, and the right portion of sidewall  48  and its inner and outer surfaces  50  and  52  taper downwardly and leftward. Outer surface  52  is convexly curved as viewed from below. Each hopper  28  is mounted on deck  20  and more particularly extends through a circular through hole  56  formed through deck  20  such that an upper portion  58  of the hopper extends upwardly from deck  20  and a lower portion  60  of the hopper extends downwardly and axially inwardly from deck  20  toward center plane CL to adjacent the bottom of the given hopper  28  and the top of the given valve assembly  42 . Upper portion  58  extends upwardly and axially outwardly from adjacent side  19  so that upper portion  58  extends outward of side  19  and higher than deck  20 . 
     Referring again to  FIG. 1 , the rear of sidewall  48  of front hopper  28 A and the front of sidewall  48  of the next hopper  28 B intersect one another at an arcuate axially elongated intersection  59  adjacent the top of the upper portions  58  of hoppers  28 A and B. Intersection  59  serves as a rear end of hopper  28 A and a front end of hopper  28 B. The rear of sidewall  48  of hopper  28 B and the front of sidewall  48  of the rear hopper  28 C intersect one another at an arcuate axially elongated intersection  61  adjacent the top of the upper portions  58  of hoppers  28 B and C. Intersection  61  serves as a rear end of hopper  28 B and a front end of hopper  28 C. Inner surface  50  defines a hopper chamber  62  which is generally conical or frustoconical and is part of interior chamber  26 . Chamber  26  of hopper  28 B extends from a front end thereof at or adjacent intersection  59  to a rear end thereof at or adjacent intersection  61 . 
     In the exemplary embodiment and with primary reference to  FIGS. 2 ,  3  and  5 , each hopper  28  includes hopper air inlet ports  63  with air inlet port chambers  64 A-C extending outwardly therefrom. These ports and chambers are formed along lower portion  60  and are lower than deck  20  and higher than valve assembly  42 . Ports  64  are circumferentially equally spaced from one another ( 120  degrees apart as viewed from the bottom). More particularly, port chamber  64 A is disposed generally along the left front of lower portion  60 , port chamber  64 B is disposed along the right front of lower portion  60  and port chamber  64 C is at the rear of portion  60 . A circular annular hopper flange  66  is rigidly secured to the bottom of the hopper and extends radially outwardly therefrom. Flange  66  is flat and horizontal as viewed from the side. Flange  66  defines a plurality of holes for receiving respectively there through a plurality of vertical bolts  68  which extend downwardly from flange  66 . 
     With primary reference to  FIGS. 2 and 3 , valve assembly  42  includes a cylindrical valve chamber wall  70  which defines a cylindrical valve chamber  72 , the top of which communicates with the bottom exit opening of hopper chamber  62  so that chamber  72  extends downwardly a short distance from the bottom of chamber  62  and serves as a hopper discharge port or passage. Bolts  68  rigidly secure chamber wall  70  to the bottom of hopper  28  with the top of wall  70  abutting flange  66  and extending downwardly therefrom. Assembly  42  further includes a cylindrical valve shaft passage wall  74  ( FIG. 3 ) which is rigidly secured to and extends horizontally outward to the left from the left side of chamber wall  70  a short distance. Thus, the inner or right end of wall  74  is secured to chamber wall  70  and extends outwardly to an outer left end. A circular annular flange  76  is rigidly secured to and extends radially outwardly from the outer left end of passage wall  74  and is formed from a flat plate which is vertical as viewed from the front. Passage wall  74 , flange  76  and the left side of chamber wall  70  define a horizontal axially extending valve shaft passage  78  which extends from the inner surface of chamber wall  70  which defines chamber  72  to the left or outer surface of flange  76 . Passage  78  is thus a through passage. The right side of chamber wall  70  defines a closed valve shaft passage  79  which extends radially outwardly to the right from the inner surface of chamber wall  70  opposite passage  78 . Thus, while through passage  78  communicates to the outside of the valve assembly from within chamber  72 , closed passage  79  does not do so. 
     With continued reference to  FIGS. 2 and 3 , a butterfly valve  80  is disposed within valve chamber  72  and is pivotally movable between a closed position shown in dashed lines and an open position shown in solid lines. Center plane CL ( FIG. 4 ) cuts through the axial center of each of chamber walls  70 , chambers  72  and valves  80 . Valve  80  is typically formed of a flat rigid plate or disc which has a circular outer perimeter for forming a seal with the circular inner perimeter or surface of chamber wall  70 . A valve shaft  82  is rigidly secured to and extends outwardly from butterfly valve  80  in opposed left and right directions and more particularly includes a right end segment  84  and a left end segment  86 . Segment  84  is mounted within passage  79  and left segment  86  is disposed within passage  78 . Valve  80  and shaft  82  are rotatable about a horizontal axially extending axis which passes through shaft  82  and passages  78  and  79 . Flange  76  defines a plurality of through holes  88  extending from the left to the right sides thereof for receiving there through horizontal axially extending bolts  90 . As described in detail further below, handle extension  46  is secured to flange  76  by bolts  90  and extends axially outwardly therefrom to the left. 
     Air piping assembly  40  includes several air pipes including an air inlet pipe  92 , a top air pipe  94 , a blow down pipe  96 , a substantially horizontal longitudinally elongated straight hopper discharge pipe  98 , a main or primary hopper aeration pipe  100 , and a plurality of hopper aeration branch pipe assemblies  102  which are respectively associated with hoppers  28 A-C. Pipes  92 ,  94 ,  96 ,  98 ,  100  and the pipes of assemblies  102  are in fluid communication with one another, with various of these pipes in direct fluid communication with others of these pipes through intersections or other connections as noted below. Aeration pipe  100  may also be referred to as a heated air pipe or blow pipe in that it becomes hot or heated during operation of an associated air pump or compressor. Pipe  100  is typically a rigid pipe formed of metal (as are pipes  92 ,  94 ,  96  and  98 ). As shown in  FIGS. 2 and 3 , each branch pipe assembly  102  includes three air pipes, namely a primary branch pipe  104  and a pair of secondary branch pipes  106 A and B. In the exemplary embodiment, pipes  104  and  106  are typically flexible pipes or hoses which are formed of an elastomeric material. 
     Referring to  FIG. 1 , the front horizontal portion of air inlet pipe  92  extends longitudinally above and adjacent front deck  22  and to the left of and adjacent front enclosure  32 . The rear portion of pipe  92  extends downwardly behind front deck  22  and axially inward below rear deck  20  to the front of pipe  98 . Top air pipe  94  is entirely above and adjacent front deck  22  and to the left of and adjacent front enclosure  32 . The front vertical portion of blow down pipe  96  is to the left of and adjacent front enclosure  32 , with the rear portion of pipe  96  extending from the bottom of the vertical portion axially inward into and through front enclosure  32  and downwardly and rearwardly to exit enclosure  32  along the rear of front deck  22  and the front of rear deck  20 . The positions of discharge pipe  98  and aeration pipe  100  are described in greater detail further below. 
     Referring again primarily to  FIG. 1 , air inlet pipe  92  has a front inlet end  108  at the front of assembly  40  adapted to receive air there through to be pumped through the remainder of assembly  40 . Inlet end  108  is removably attachable to an air feed line  110  which is connected to an air pump or compressor typically mounted on tractor  2  or another location typically not on trailer  1 . Inlet end  108  communicates directly with external ambient atmosphere when not connected to feed line  110 . Air inlet pipe  92  also has an opposed rear lower outlet end  114  which is rearward of and lower than front inlet end  108 . Inlet end  108  serves as an upstream end while rear end  114  serves as a downstream end inasmuch as airflow typically enters end  108  and exits end  114  during operation of pump or compressor  112 . Top air pipe  94  has a lower inlet or upstream end  116  which is connected to inlet pipe  92  at an intersection therewith. Top air pipe  94  has an upper outlet or downstream end  118  which is connected to blow down pipe  96  at an intersection therewith. Thus, top air pipe  94  is configured to receive airflow from air inlet pipe  92  via end  116  whereby the airflow may exit outlet end  118  into blow down pipe  96 . Blow down pipe  96  has an upper end  120  and a lower end  122 . Upper end  120  is connected at an intersection to tank  24  adjacent the top thereof whereby blow pipe  96  is in direct fluid communication with chamber  26 . Top end  120  may serve as an inlet or upstream end or an outlet or downstream end of blow pipe  96  depending on the position of various valves, as discussed further below. Lower rear end  122  serves as an exit or outlet end through which airflow is discharged into the ambient atmosphere external to trailer  1 . 
     With primary reference to  FIG. 1 , discharge pipe  98  has a front inlet or upstream end  124  which is connected to rear outlet end  114  of air inlet pipe  92  forward of and adjacent the front valve assembly  42  and the bottom of hopper  28 A. Discharge pipe  98  further includes a rear outlet or downstream end  126  which is rearward of the rear valve assembly  42  and the bottom of rear hopper  28 C. End  126  is typically adjacent rear end  8  of trailer  1  and serves as a discharge end through which airflow and material  27  are discharged adjacent the rear end  8 . Pipe  98  thus extends from forward of all the valve assemblies  42  and all of the bottoms of the hoppers  28 A-C to rearward of all the valve assemblies  42  and all of the bottoms of the hoppers  28 A-C. Pipe  98  is typically straight, horizontal and parallel to center plane CL ( FIG. 5 ,  6 ) from adjacent the bottom of front hopper  28 A and front valve assembly  42  to adjacent the bottom of rear hopper  28 A and rear valve assembly  42 . 
     With primary reference to  FIG. 1 , primary aeration pipe  100  has a front inlet or upstream end  128  through which air flows into pipe  100  and a rear or downstream end  130  which is capped or closed in the exemplary embodiment. Upstream end  128  is connected at an intersection to air inlet pipe  92  at a location downstream of intersection  116  and upstream of the connection between downstream end  114  and upstream end  124 . Inlet end  128  is thus upstream of all branch pipe assemblies  102  and their intersections with aeration pipe  100 . Downstream end  130  is typically longitudinally adjacent and usually somewhat rearward of rear hopper  28 C and the rear valve assembly  42 . 
     In the preferred embodiment of the trailer  1 , the trailer  1  includes an integral toolbox  200 . As shown in  FIGS. 1 and 5 , in the preferred embodiment, the toolbox  200  is located between two of the hoppers  28 . For example illustration purposes, the tool box  200  is shown integrally located in the lower enclosure  38 A between hoppers  28 A and  28 B in  FIGS. 1 and 5 . Of course, the tool box can be located between any two adjacent hoppers  28 . In other configurations of the preferred embodiment, the tool box  200  can be integrally located in the front enclosure  32  as integral tool box  300  shown in  FIGS. 1 and 8  or in the rear enclosure  34  as integral tool box  400  as shown in  FIG. 9 . The doors of integral tool boxes  300  and  400  are generally rectangular in shape but in other ways can be similar to integral tool box  200  that is discussed in further detail below. When tool box  300  is located in the front enclosure  32  as shown in  FIG. 1 , then the built-in ladder  36  can be located at the rear of the trailer  1 . However, when the tool box  400  is formed in the rear enclosure  34  as shown in  FIG. 9 , then the built-in ladder  36  can be relocated and formed integrally with forward enclosure  32 . 
     The integral tool box  200  of FIGS.  1  and  5 - 7  is formed between two hoppers  28  with a door  201 , a front wall  214 , a top side  202 , a bottom side  204 , a right side  206  and a left side  208 , as well as an angled top left side  210  and an angled top right side  212 . These sides form a perimeter around the front wall  214 . Front wall  214  is formed out of a sheet of metal and has a front side  216  and a back side  218 . In the preferred embodiment, rearward (from the front side  216 ) projecting side walls  202 A,  204 A,  206 A,  208 A,  210 A,  212 A can form a perimeter wall  213  encircling the outside edges of the front wall  214  to form a cavity  220  between these walls and the front wall  214 . Perimeter wall  213  can be formed by bending and welding plates of metal together or in other ways as understood by those of ordinary skill in the art. 
     The toolbox door  201  includes a hinge  222  for attaching it to a side wall of the lower enclosure  38 A. The hinge  222  can be a metal hinge such as an elongated piano-type of hinge and hinge  222  can be attached a front side wall  236  of the lower enclosure  38 A with bolts  224  or other suitable fasteners. Door  201  also has a handle  226  with a locking mechanism  228  for locking the door  201  in a closed position to the lower enclosure  38 . The locking mechanism  228  is adapted to move a locking tab  230  into and out of a locking bar (not shown) on the lower enclosure  38 A. The handle  226  with the locking mechanism  228  can include one or more keys for locking the handle  226  in the locked position to prevent unauthorized access to the integral toolbox  200 . 
     The front side wall  236  of the lower enclosure  38 A on the right side  16  of the trailer  1  is formed similar to a back side wall of the lower enclosure on the left side  14  of the trailer. These two sides, together with an upper surface  240  of the lower deck  20  and lower side walls  238  of hoppers  28 A and  28 B, form an enclosed tool box chamber  246  with an opening  248  generally complementary shaped to the door  201 . 
     In the preferred embodiment, projecting side walls  252 ,  254 ,  256 ,  258 ,  260 ,  262  can form a perimeter wall  264  encircling the outside edges of opening  248  that is complementary the perimeter wall  213  formed by projecting side walls  202 A,  204 A,  206 A,  208 A,  210 A,  212 A of the door  201 . The perimeter wall  264  can be formed by bending and welding plates of metal together so that the edges of the perimeter wall attached to the lower enclosure  38 A are complementary shaped to the curves of the lower enclosure  38 A so that there are no gaps between the lower enclosure  38 A and the perimeter wall  264 . However, the perimeter wall  264  encircling the outside edges of opening  248  forms a smaller perimeter wall that fits inside perimeter wall  213  of the door  201  when the door  201  is in the closed position. 
     A water seal  268  can be attached to the outward most edge of the perimeter wall  264  so that when the door  201  is in the closed position the surface of the back side  218  of the front wall  214  will press against the water seal  268  to create a water-tight fitting. The water seal  268  can be any suitable material such as a polymer type of material that has some give so that it conforms to the edge of the perimeter wall  213  of the door  201 . 
     In the foregoing description, certain terms have been used for brevity, clearness, and understanding. No unnecessary limitations are to be implied therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed. Therefore, the invention is not limited to the specific details, the representative embodiments, and illustrative examples shown and described. Thus, this application is intended to embrace alterations, modifications, and variations that fall within the scope of the appended claims. 
     Moreover, the description and illustration of the invention is an example and the invention is not limited to the exact details shown or described. References to “the preferred embodiment”, “an embodiment”, “one example”, “an example”, and so on, indicate that the embodiment(s) or example(s) so described may include a particular feature, structure, characteristic, property, element, or limitation, but that not every embodiment or example necessarily includes that particular feature, structure, characteristic, property, element or limitation. Furthermore, repeated use of the phrase “in the preferred embodiment” does not necessarily refer to the same embodiment, though it may.