Abstract:
Taught herein is a trailer having a gooseneck that can be engaged with the fifth wheel of a road tractor, rear truck unit, and a detachable cargo deck connecting the gooseneck with the truck unit. The cargo deck may be detached from the gooseneck and rested on the ground to allow heavy equipment to be loaded onto the cargo deck. The cargo deck can be reattached to the gooseneck, and elevated and locked into any one of three positions, each substantially parallel with the road, by an elevating means in the gooseneck and the truck unit. Thus the trailer of the present invention can be configured to accommodate cargo have a wide range of weight and size.

Description:
CROSS REFERENCE 
     This application is a continuation-in-part of pending application Ser. No. 11/821,499, filed Jun. 25, 2007 now abandoned. 
    
    
     TECHNICAL FIELD 
     This invention relates to platform trailers and particularly to platform trailers with detachable goosenecks, which permit the trailers&#39; center and rear decks to be adjusted to multiple heights. 
     BACKGROUND 
     Platform trailers are used to transport a variety of cargo that can withstand exposure to the weather or a wide range of road conditions. These trailers can be classified into three categories: “lowboy” (also known as “gooseneck”), “flatbed,” and “drop deck” trailers. 
     Lowboy trailers, as the term implies, have low “beds” or “decks,” situated close to the road so they can carry tall items that must clear bridges, power lines, and other over head obstacles, while providing a low center of gravity to enhance stability of large loads. Typically a lowboy trailer has a deck that can be detached from the assembly that connects it to the fifth wheel of a road tractor, commonly referred to as a “gooseneck,” to facilitate the loading of heavy items such as a piece of construction equipment. A flatbed trailer has a deck that extends the entire length of the trailer and is situated just above the wheels of the tractor and the trailer&#39;s wheel assemblies. Its standardized deck height provides good road clearance, and the flatbed trailer is designed to accept cargo, such as a shipping container, from a loading dock with little or no lifting. The drop deck trailer is less common than the other two types. Its deck is above that of a lowboy trailer yet below that of a flatbed trailer and is typically designed to carry specific items. 
     There is a need to have a single trailer that can be easily configured as a lowboy, flatbed, or drop deck trailer to accommodate any cargo the trailer may be required to carry. To some extent, this need has been recognized in the art. For example, see U.S. Pat. Nos. 2,676,783, 4,806,065, 5,059,083, 6,425,627. However, the trailers of the art typically allow for configuration only as lowboy or flatbed trailers, but not as drop deck trailers for which a need still exists. Further, the trailers of the art are complicated and time consuming to reconfigure, and in some cases are less stable than fixed deck trailers. 
     SUMMARY OF THE INVENTION 
     The present invention provides a detachable trailer comprising a gooseneck having a deck and capable of coupling with a road tractor, a truck assembly distal to the gooseneck, and a detachable center deck connecting the gooseneck to the truck assembly and capable of being moved to any of three horizontal positions, between the gooseneck and the truck assembly with each position being substantially parallel to the surface upon which the trailer is situated. The truck assembly has a deck, a wheel assembly, and a means, of moving this deck up or down. The center deck may be locked in position between the gooseneck and to the truck assembly, thereby allowing the trailer to be configured as a lowboy trailer, a drop deck trailer, or a flatbed trailer. This invention alleviates attachment and detachment problems caused by misalignment of gooseneck and the deck, thus expediting conversion from one configuration to another. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1   a - FIG. 1   d  are side views of the present trailer illustrating three positions to which the center and rear deck can be configured. 
         FIG. 2  is a perspective view of the outer frame for elevator and lock assembly in gooseneck of the present trailer. 
         FIG. 3  is a perspective view of riser screws, threaded blocks, lift and lock arm and lockbox in gooseneck, and trailer lift pin with collar and lockbox in trailer. 
         FIG. 4  is a perspective view of electric motors that drive riser screws and lift, and lock arm. 
         FIG. 5  and  FIG. 6  are perspective views of rear deck, i.e., truck deck, of trailer illustrating rear deck raised and lowered by air system in relation to riser screws, threaded block and lock box assembly. 
         FIG. 7  is a view of I-beam supporters in a rear deck of trailer in raised ( FIG. 7   a ) and lowered ( FIG. 7   b ) positions in relation to tandem beams. 
         FIG. 8  is a perspective cross sectional view of lock bar and threaded screw in relation to the threaded block in gooseneck and threaded block in the deck. 
         FIG. 9  is a perspective view of lockbox assembly in relation to gooseneck and deck. 
         FIG. 10   a - FIG. 10   d  is a series of views of multi-positions available to drop trailer along with the bottom view of trailer&#39;s landing gear device embedded in frame of the trailer. 
     
    
    
     DETAILED DESCRIPTION 
     The present trailer can be configured as a lowboy, drop bed, or flatbed trailer quickly and efficiently. Thus within minutes, this one trailer can be configured to do the job of three trailers. Therefore, an owner of the present trailer can significantly reduce his or her investment in trailers and still carry substantially any load amenable to a platform trailer. Such a reduction in investment is particularly attractive to a small, owner-operated business with limited capital. Further, the present trailer may be fitted with tanks for carrying any liquids typically carried by tanker rigs. 
     The following terms frequently used herein are defined below: 
     “Road tractor” or “tractor” is a motor vehicle, usually diesel powered, commonly used to pull a semi-trailer along a road. Typically, at the rear of such a vehicle is a “fifth wheel,” i.e., a mechanism for securely attaching a semi-trailer to the vehicle yet allowing for turning. 
     “Trailer” is a semi-trailer that typically has an elongated, cargo carrying frame supported at one end by a truck assembly and at the other end by a tractor to which the trailer is connected by means of a fifth wheel mechanism. In common usage, a trailer and road tractor are associated and the combination is often referred to as a “semi,” “tractor—trailer truck,” or “tractor—trailer rig” and are ubiquitous on public highways 
     “Truck assembly” or “truck” is the collection of wheels, axes, and associated components that support one end of a trailer. For some trailers, e.g. those designed to carry very heavy loads, two or more trucks may be required 
     “Gooseneck” is the curved section of a lowboy trailer that is connected to the end of the deck distal from the truck and connects the trailer to the fifth wheel of the tractor. The present trailer employs a gooseneck as will be explained below. 
     “Deck assembly,” “deck,” “bed assembly,” or “bed” is that portion of a trailer that supports the cargo and typically has an underlying frame and a substantially flat surface. A trailer&#39;s deck may be comprised of multiple sub decks, as is the case with the trailer of the present invention. Accordingly, as used herein, “center deck” is the deck assembly between the gooseneck and the truck. 
     “Ground” means ground in the common meaning of this word, but herein, also includes any surface covering the ground which supports the trailer, such as a hardstand, road, etc. 
       FIG. 1   a - 1   d  constitute an overview of the present trailer, i.e., trailer  1 , connected to the fifth wheel  2  of tractor  4  that is mounted above the rear axle assembly of tractor  4 . (For clarity of illustration, only the rear section of tractor  4  is shown. Further, the bracket indicating trailer  1  does not include tractor  4  or any portion thereof, and is understood to also apply to  FIG. 1   a - 1   c .) As illustrated in these figures, the major components of the trailer are truck assembly (hereinafter, “truck”)  8 , center deck  10 , and gooseneck  13 . 
       FIG. 1   a  shows center deck  10  detached from gooseneck  13  with the end of the deck proximal to the gooseneck (when attached) resting on the ground and with the distal end connected to truck  8 . Thus, tractor  4  carrying gooseneck  13  may be moved away from center deck  10  to allow cargo to be loaded at ground level. For example, a bulldozer might be driven onto center deck  10 . After the cargo is loaded onto center deck  10 , the deck and gooseneck  13  may be reconnected, and the proximal (distal with respect to truck  8 ) end of the deck raised by an elevating means (discussed below) of the gooseneck until the deck is parallel to the ground, yet close to the ground, forming a lowboy trailer as illustrated in  FIG. 1   b.    
     The elevating means of gooseneck  13  and the corresponding elevating means of truck  8  may be used to raise center deck  10  to its maximum height to form a flatbed trailer as shown in  FIG. 1   d . (To achieve the position shown in  FIG. 1   d , the top part of truck  8  must also be raised and the means for doing so is discussed below). Alternatively, center deck  10  may be raised approximately midway between the positions illustrated in  FIG. 1   b  and  FIG. 1   d  to form a drop deck trailer as shown in  FIG. 1   c . In each of the three positions illustrated in  FIG. 1   b - 1   d , a locking means discussed herein below is employed. 
     Referring now to  FIGS. 2 ,  3 , and  4  collectively, outer frame  30  of gooseneck  13  shows three sets of predetermined height adjustment holes  29   a - 29   c  ( FIG. 2 ) corresponding to deck levels  1  through  3  respectively in which the lock bar assembly (discussed below in connection with  FIGS. 8-9 ) slides through. (Deck levels  1  through  3  are depicted in  FIG. 1   b  through  1   d  respectively.) As seen in  FIG. 3 , outer frame  30  has been removed to show riser blocks  22   a  riser screws  20   a  and a trailer lift arm  14 .  FIG. 2  shows gooseneck deck  26 , which provides additional deck space when the trailer is configured as a flatbed trailer.  FIG. 4  (an abridged version of  FIG. 2 ) shows electric motors  21   a  that operate elevator screws  20   a.    
     Again referring to  FIGS. 1   a - 1   d ,  2 ,  3 , and  4 , once center deck  10 , resting on the ground, is loaded, e.g. with a bulldozer, tractor  4  with gooseneck  13 , which is locked in a pivotal fifth wheel  2 , is backed to center deck  10 . Trailer  1  is connected to tractor  4  by towing pin  36  (explicitly shown in  FIG. 3 ) that engages fifth wheel  2  of tractor  4 . Connection of trailers to tractors by fifth wheel and towing pins (also referred to as “kingpins”) are extensively employed in this art. 
     Continuing to refer to  FIG. 1   a - 1   d ,  2 ,  3 , and  4  collectively, once gooseneck  13  which is raised by tractor  4  and electric power from the tractor&#39;s electrical system is connected to the trailer, trailer lift arm  14 , which is preset to face down before backing, is now activated by electric motor  45 , which rotates lift arm  14  (explicitly illustrated in  FIG. 3  and  FIG. 4 ). At a predetermined degree of rotation, lift arm  14  makes contact from below with trailer lift pin  16  eventually lifting center deck  10  as lift arm  14  rotates upward lifting center deck  10 . Continued rotation then draws both gooseneck  13  and center deck  10  together as lift arm  14 . Approximately 180 degrees from starting, i.e. down position, lift arm  14  is straight up and locking trailer lift pin  16  in place ( FIG. 3 ) close to rotating axis of lift arm  14 . At this time, slide holes  38  in riser blocks  22   a  align with lock boxes  18  in center deck  10  and predetermined height adjustment holes  29   a - 29   c  in gooseneck outer frame  30 . In  FIG. 2 , for clarity, the three possible positions of only one of the two slide holes are shown. 
     Referring now to  FIG. 8  and  FIG. 9 , alignment of the riser blocks  22   a  with lock boxes  18  allows lock bars  15 , housed in gooseneck outer frame  30 , to be activated ( FIG. 9 ) causing the lock bars to slide through slide holes  38  in riser blocks  22   a  ( FIG. 3 ) and predetermined height adjustment holes  29   a - 29   c  ( FIG. 2 ) then continue into center deck  10  lock boxes  18 . Referring to now to  FIG. 9 , compressed air to operate pneumatic motor  37   a  is supplied by the compressor of tractor  4  and stored in air cylinder  37   b . (For simplicity of illustration,  FIG. 9  shows just one of the two unit associated with riser blocks  22   a .) Pneumatic motor  37   a  turns threaded rod  17  in a direction that causes it to spread the two lock bars  15  into lock boxes  18  in center deck  10  then continue into a threaded block  19  drawing and locking center deck  10  to gooseneck  13 . Referring to  FIG. 1   b  now, trailer  1  is ready for transport as a lowboy trailer. 
     To move from the position shown in  FIG. 1   b , i.e. lowboy position, to the position shown in  FIG. 1   c , i.e. drop deck position, the operator unlocks lock bars  15  in gooseneck  13  by reversing the direction of pneumatic motor  37   a . Next, the operator engages electric motors  21   a  ( FIG. 4 ) for elevator screws  20   a  to raise elevator block  22  in gooseneck  13  to height adjustment holes  29   b  in outer frame  30  ( FIG. 1   a - 9 ). Once lock boxes  18  and slide hole  38  are aligned, the operator engages lock bars  15  to lock into height adjustment holes  29   b , and the operator simultaneously engages electric motors  21   b  turning elevator screws  20   b  in truck deck  23  shown in  FIG. 5  to its midlevel position as shown in  FIG. 5 . For clarity, only one of electric motors  21   b  is shown in  FIG. 5 , but the other is in a corresponding position on the other side of truck deck  23 . The function of electric motors  21   b , elevator screws  20   b , and height adjustment holes  29   b  correspond in form and function to those housed in gooseneck  13  and described above, i.e.,  21   a ,  20   a , and  29   a  respectively. Center deck  10  is now in the position shown in  FIG. 1   c , so that trailer  1  is now ready for transport as a drop deck trailer. 
     Moving from the drop bed position shown in  FIG. 1   c  to the position shown in  FIG. 1   d , the flat bed position, follows a similar procedure to that described above. The operator unlocks lock bars  15 , and engages electric motors  21   a  for elevator screws  20   a  to raise elevator block  2   b  and engages lock bars  15  to lock into height adjustment holes  29   c . Simultaneously, the operator also engages truck deck elevators  24 . When height at gooseneck  13  reaches the level shown in  FIG. 1   d , truck deck  23  is raised to the level in  FIG. 6  by truck deck elevators  24  and locked in place by folding I-beam supporters  25  that rest on tandem beams  28  of truck  8  ( FIG. 5 ,  FIG. 6 ,  FIG. 7   a , and  FIG. 7   b ) to an upright position. Trailer  1  is now configured as a flatbed trailer as shown in  FIG. 1   d.    
     In the flatbed configuration the total, continuous deck length is the combined lengths of gooseneck deck  26  ( FIG. 2 ), center deck  10  ( FIG. 1   a - 1   d ), and truck deck  23  ( FIG. 5-FIG .  6 ). Thus, trailer  1  configured as a flatbed has an effective continuous, single cargo carrying deck surface extending from tip of gooseneck  13  proximal to the tractor (as shown in  FIG. 1   d ) to the distal end of the truck. Importantly, this deck surface is substantially parallel to the ground, a feature that facilitates load stability 
     Referring to  FIG. 10   a - FIG. 10   d , with trailer  1  configured as a drop bed ( FIG. 10   c ) and a flatbed ( FIG. 10   d ), landing support  35  can be used to drop center deck  10  for loading or leaving present trailer  1  parked.  FIG. 10   b  is a bottom view of the trailer. To release the center deck  10  in positions shown in  FIG. 10   c  and  FIG. 10   d , once landing support  35  is engaged, the operator disengages gooseneck  13  ( FIG. 1   a - 1   d ) lock bars  15  ( FIG. 8 ,  9 ) and trailer lift arm  14  ( FIG. 3 ) is then rotated down releasing trailer lift pin  16  ( FIG. 3 ) releasing center deck  10  from the gooseneck leaving trailer lift arm and trailer lift pin in position to reattach with no adjustments.