Abstract:
A trailer stabilizer and signaling system comprising: (a) a repositionable freight trailer stabilizer comprising a frame having mounted thereto a wheel, the repositionable freight trailer stabilizer including a repositionable jack; and, (b) a stabilizer signaler operatively coupled to the trailer stabilizer, the stabilizer signaler including a deployable signal configured to confirm the trailer stabilizer is secured under a parked freight trailer.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 13/316,801, filed Dec. 12, 2011, which was a continuation of Patent Cooperation Treaty Application Serial No. PCT/US11/37260, filed May 19, 2011, which claimed the benefit of U.S. Provisional Patent Application Ser. No. 61/346,143, filed May 19, 2010, entitled “TRAILER DOCKING REPOSITIONABLE SUPPORT” and U.S. Provisional Patent Application Ser. No. 61/438,232, filed Jan. 31, 2011, entitled “TRAILER STABILIZER,” the disclosure of each is incorporated herein by reference. 
     
    
     RELATED ART 
       [0002]    1. Field of the Invention 
         [0003]    The present disclosure is directed to supports utilized to secure freight trailers at a loading dock while dock personnel load and/or unload cargo from the freight trailers. 
         [0004]    2. Related Art of Interest 
         [0005]    Distribution warehouses are a necessary component of commerce in the twenty-first century. These warehouses may act as a clearinghouse for shipments from various product suppliers and centralize the distribution of goods. Large chain retailers utilize warehouses to generate shipments to particular points of sale that are specific to the needs of consumers in that area, without requiring the original manufacturer of the goods to identify consumer demand at each point of sale and correspondingly deliver the particular goods to each point of sale. 
         [0006]    An exemplary distribution warehouse generally includes, fifteen or more loading docks, with each loading dock adapted to receive a single freight trailer of a semi truck. A loading dock typically includes an opening elevated above ground level to match the height of the floor of the freight trailer. The relatively equal height between the floor of the loading dock and the floor of the trailer enables lift trucks (i.e., forklifts) and other material handling devices to move freely back and forth between the warehouse and interior of the freight trailer. 
         [0007]    In an exemplary sequence, a loading dock opening of a warehouse is initially unoccupied by a freight trailer. Thereafter, a semi trailer driver or yard truck driver backs the rear opening of a freight trailer into alignment with the opening of the dock. After the rear of the freight trailer is properly aligned and positioned adjacent to the dock opening, the driver will either continue the engagement between the truck and trailer, or discontinue the engagement and relocate the truck to a remote location. In the context of yard trucks, the yard truck is only connected to the freight trailers long enough to position it adjacent to the loading dock opening. In an exemplary day, the yard truck may connect to and disconnect from one hundred or more freight trailers. 
         [0008]    In summary fashion, a yard truck is a dedicated tractor that stays at the warehouse location and is only used to reposition freight trailers (not to tow the trailers on the open highways). By way of example, a warehouse may have ten dock openings, but have fifty trailers waiting to be unloaded. In order to expedite freight unloading and loading, as well as the convenience of the semi truck drivers that deliver to or pick up the freight trailers from the warehouse, the freight trailers need to be shuffled. This means that freight trailers do not include dedicated semi tractors continuously connected to them. Instead, because no semi truck is connected to many, if not all, of the freight trailers at a warehouse location, a yard truck is necessary to reposition the freight trailers while at the warehouse location. 
         [0009]    An exemplary process for discontinuing engagement between the yard truck and the freight trailer includes initially raising a hydraulic fifth wheel on the yard truck to raise the front end of the trailer above its normal ride height. While the front end is raised, the yard truck driver lowers landing gear of the freight trailer, which comprises a pair of equal length jacks permanently mounted to the trailer, so that lowering of the fifth wheel is operative to set down the freight trailer on its landing gear. When the freight trailer is set down on its landing gear, the freight trailer is freestanding (i.e., without a mechanical connection between the king pin of the freight trailer and the fifth wheel of the yard truck). After the freight trailer is freestanding, associated pneumatic and electrical connections between the yard truck and trailer are disconnected so that the brakes of the freight trailer are locked. Thereafter, the yard truck pulls out from under the freight trailer, thereby leaving the trailer adjacent to the dock opening and being supported at the front end using only the trailer&#39;s landing gear. 
         [0010]    When loading and unloading cargo from a freestanding freight trailer, the movement of the lift truck along the floor of the freight trailer causes the freight trailer to move as well. While some movement of the freight trailer is inevitable, considerable movement can result in the trailer becoming separated from the dock or possibly tipping over. More importantly, the landing gear of the freight trailer is not designed to accommodate the weight of a fully loaded trailer, let alone the dynamic forces generated by a lift truck moving through a partially loaded freight trailer. Even further, the high center of gravity associated with most trailers makes the likelihood of tipping over a real possibility. The obvious implications of a freight trailer tipping over include damage to the goods within the trailer, the trailer itself, and the lift truck, not to mention the possible serious injury to or death of the lift truck operator. 
         [0011]    There is a need in the industry for a reliable support that maintains the relative position of the freight trailer with respect to the dock and inhibits the trailer from tipping over, possibly causing serious bodily injury or death, which does not rely solely on the landing gear of the freight trailer. 
       INTRODUCTION TO THE INVENTION 
       [0012]    The present disclosure is directed to supports associated with a loading/unloading dock and, more specifically, to repositionable supports that secure freight trailers in position at a loading dock while dock personnel load and/or unload cargo from the trailers. The present disclosure includes a repositionable structure having a fifth wheel to capture the king pin of a freight trailer, thereby securing the repositionable structure to the trailer. The repositionable support may also include one or more of an electrical, a hydraulic, and a pneumatic interface for coupling directly to the yard truck or other truck using conventional connections, such as glad hands and electrical disconnects. Unlike conventional stabilizing products, the exemplary embodiments of the instant disclosure may provide support for the front end of a parked freight trailer without the need for deployment of the landing gear (i.e., the landing gear touching the ground). After the repositionable structure has been mounted to the trailer by way of the king pin and fifth wheel interface, wheel chocks may be deployed and brakes associated with the repositionable device may be locked to inhibit horizontal movement of the trailer away from the loading dock. In exemplary form, the repositionable structure may include a winch that is adapted to engage a pavement cleat, thereby forming a compression fit between the king pin and fifth wheel of the repositionable support using the tension from the winch cable. The repositionable support may also include a communicator operative to relay a communication to an internal display within the warehouse that indicates whether the repositionable support is properly mounted to the freight trailer. 
         [0013]    An exemplary repositionable structure includes a frame and an axle mounted to the frame. By way of example, the axle includes a pair of tandem wheels, with brakes, mounted proximate opposite ends of the axle. However, the wheels may be single wheels and not include brakes. A vertically repositionable fifth wheel is also mounted to the frame and is adapted to receive the king pin of a freight trailer. A pair of repositionable wheel chocks may also be mounted to the frame. Also on board the frame may be a freight trailer positioning communicator adapted to signal a warehouse display indicating whether the trailer has been secured while at the loading dock. Pneumatic, hydraulic, and electrical lines may also be associated with the frame that are in communication with any wheel brakes, the repositionable fifth wheel, and any positioning communicator. The foregoing lines may be powered directly from the yard truck, or the frame may include individual power sources for one or more of the foregoing lines. 
         [0014]    After the yard truck has positioned the repositionable support into engagement with the king pin of the freight trailer, the brakes (if included) are applied and the winch (if included) is deployed to lock the support in position below a frontal portion of the trailer. Thereafter, the support remains under the frontal portion of the trailer as the trailer is loaded or unloaded. Similarly, after the support is secured in position beneath the frontal portion of the freight trailer, the yard truck disconnects from the repositionable structure and continues jockeying the remaining freight trailers at the warehouse location. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]      FIG. 1  is an elevated perspective view of an exemplary trailer stabilizer in accordance with the instant disclosure. 
           [0016]      FIG. 2  is a bottom perspective view of the exemplary trailer stabilizer of  FIG. 1 . 
           [0017]      FIG. 3  is a left side profile view of the exemplary trailer stabilizer of  FIG. 1 . 
           [0018]      FIG. 4  is a top view of the exemplary trailer stabilizer of  FIG. 1 . 
           [0019]      FIG. 5  is a front view of the exemplary trailer stabilizer of  FIG. 1 . 
           [0020]      FIG. 6  is a rear view of the exemplary trailer stabilizer of  FIG. 1 . 
           [0021]      FIG. 7  is an elevated perspective view, from the left rear, of an exemplary gooseneck frame and cart frame in accordance with the instant disclosure. 
           [0022]      FIG. 8  is a bottom perspective view of the exemplary gooseneck frame and cart frame of  FIG. 7 . 
           [0023]      FIG. 9  is an elevated perspective view, from the front right, of the exemplary gooseneck frame and cart frame of  FIG. 7 . 
           [0024]      FIG. 10  is a right side profile view of the exemplary gooseneck frame and cart frame of  FIG. 7 . 
           [0025]      FIG. 11  is an overhead view of the exemplary gooseneck frame and cart frame of  FIG. 7 . 
           [0026]      FIG. 12  is an elevated perspective view, from the left side, of the exemplary repositionable hook assembly and lock box in accordance with the instant disclosure. 
           [0027]      FIG. 13  is a top view of the exemplary repositionable hook assembly and lock box of  FIG. 12 . 
           [0028]      FIG. 14  is an elevated perspective view of the exemplary repositionable hook assembly and internal components of the lock box of  FIG. 12 . 
           [0029]      FIG. 15  is a left side profile view of the exemplary repositionable hook assembly and lock box of  FIG. 12 . 
           [0030]      FIG. 16  is a right side profile view of the exemplary repositionable hook assembly and internal components of the lock box of  FIG. 12 . 
           [0031]      FIG. 17  is a top view of an exemplary tilt subassembly of an exemplary fifth wheel assembly in accordance with the instant disclosure. 
           [0032]      FIG. 18  is a bottom perspective view, from the front, of the exemplary tilt subassembly of the exemplary fifth wheel assembly of  FIG. 17 . 
           [0033]      FIG. 19  is a bottom view of the exemplary tilt subassembly of the exemplary fifth wheel assembly of  FIG. 17 . 
           [0034]      FIG. 20  is a profile view, from the front, of the exemplary tilt subassembly of the exemplary fifth wheel assembly of  FIG. 17 . 
           [0035]      FIG. 21  is an elevated perspective view, from the left rear, of an exemplary pivoting subassembly of an exemplary fifth wheel assembly in accordance with the instant disclosure. 
           [0036]      FIG. 22  is a bottom perspective view, from the left front, of the exemplary pivoting subassembly of the exemplary fifth wheel assembly in accordance with the instant disclosure. 
           [0037]      FIG. 23  is an elevated perspective view, from the right front, of a portion of the exemplary pivoting subassembly of the exemplary fifth wheel assembly in the context of the cart frame. 
           [0038]      FIG. 24  is an elevated perspective view, from the right rear, of an exemplary repositionable jack assembly in the context of the cart frame in accordance with the instant disclosure. 
           [0039]      FIG. 25  is an elevated perspective view, from the left side, of the exemplary repositionable jack assembly in the context of the cart frame shown in  FIG. 24 . 
           [0040]      FIG. 26  is an overhead view of the exemplary repositionable jack assembly in the context of the cart frame shown in  FIG. 24 . 
           [0041]      FIG. 27  is a magnified view of a left half of the exemplary repositionable jack assembly of  FIG. 24 , shown without the cross-plate. 
           [0042]      FIG. 28  is a forward view of the left half of the exemplary repositionable jack assembly of  FIG. 24 , shown without the cross-plate. 
           [0043]      FIG. 29  an elevated perspective view of the right half of the exemplary repositionable jack assembly of  FIG. 24 , shown without the cross-plate. 
           [0044]      FIG. 30  is an exemplary schematic diagram showing the fluid network, using a liquid, incorporated in the alternate exemplary embodiment. 
           [0045]      FIG. 31  is an elevated perspective view, from the right rear, of yet another alternate exemplary trailer stabilizer that includes integrated wheel stops. 
           [0046]      FIG. 32  is an overhead view of the alternate exemplary trailer stabilizer of  FIG. 31 . 
           [0047]      FIG. 33  is an elevated perspective view from the front left of a second exemplary trailer stabilizer in accordance with the instant disclosure showing certain features. 
           [0048]      FIG. 34  is an elevated perspective view from the front left of a second exemplary trailer stabilizer in accordance with the instant disclosure showing other features. 
           [0049]      FIG. 35  is an elevated perspective view from the rear left of a second exemplary trailer stabilizer in accordance with the instant disclosure showing certain features. 
           [0050]      FIG. 36  is a magnified, elevated perspective view from the rear left of a second exemplary trailer stabilizer in accordance with the instant disclosure showing certain features. 
           [0051]      FIG. 37  is a rear view from the rear left of a second exemplary trailer stabilizer in accordance with the instant disclosure showing certain features. 
           [0052]      FIG. 38  is a frontal view from the rear left of a second exemplary trailer stabilizer in accordance with the instant disclosure showing certain features. 
           [0053]      FIG. 39  is a frontal view from a stabilizer housing for transmitters and receivers in accordance with the instant disclosure. 
           [0054]      FIG. 40  is a frontal view from a dock cabinet for transmitters, receivers, and displays in accordance with the instant disclosure. 
           [0055]      FIG. 41  is a frontal view from an interior warehouse cabinet in accordance with the instant disclosure. 
           [0056]      FIG. 42  is an exemplary wiring diagram showing at least a portion of the control structure of the control circuitry of the second exemplary embodiment relating to the stabilizer and the dock cabinet. 
           [0057]      FIG. 43  is an exemplary wiring diagram showing at least a portion of the control structure of the control circuitry of the second exemplary embodiment as it relates to the interior warehouse cabinet. 
           [0058]      FIG. 44  is an overhead view of the second exemplary embodiment positioned underneath a parked trailer at a loading dock facility, along with an exemplary position of the dock cabinet and interior warehouse cabinet. 
           [0059]      FIG. 45  is an overhead view of an exemplary trailer stabilizer in accordance with the instant disclosure. 
           [0060]      FIG. 46  is a perspective, cut away view of an exemplary brake assembly for use with the exemplary trailer stabilizer of  FIG. 45 . 
           [0061]      FIG. 47  is a schematic diagram of an exemplary braking system for use with the exemplary trailer stabilizer of  FIG. 45 . 
           [0062]      FIG. 48  is an underneath, perspective view of an exemplary repositioning assembly for use in repositioning the wheel chocks of the exemplary trailer stabilizer of  FIG. 45 . 
           [0063]      FIG. 49  is an elevated perspective view of a repositionable wheel chock, in the storage position, for use with the exemplary trailer stabilizer of  FIG. 45 . 
           [0064]      FIG. 50  is an elevated perspective view of the repositionable wheel chock of  FIG. 49 , shown just prior to complete deployment. 
           [0065]      FIG. 51  is an elevated perspective view of the exemplary trailer stabilizer of  FIG. 45 . 
           [0066]      FIG. 52  is a profile view of an exemplary yard truck coupled to the trailer stabilizer of  FIG. 45 , shown being backed under a commercial freight trailer. 
           [0067]      FIG. 53  is a profile view of the trailer stabilizer of  FIG. 45  mounted and secured to the commercial freight trailer of  FIG. 52 . 
           [0068]      FIG. 54  is an overhead view of an exemplary layout at a warehouse or loading dock facility showing placement of the trailer stabilizer of  FIG. 45  and the visual display components. 
           [0069]      FIG. 55  is a profile view of another exemplary trailer stabilizer in a disengaged position. 
           [0070]      FIG. 56  is a profile view of the exemplary trailer stabilizer of  FIG. 55  in an engaged position. 
           [0071]      FIG. 57  is a profile view of the exemplary draw bar and associated hook in  FIG. 55 . 
           [0072]      FIG. 58  is a top view of the exemplary draw bar and associated hook in  FIG. 55 . 
           [0073]      FIG. 59  is a top view of the exemplary pavement cleat in  FIG. 55 . 
           [0074]      FIG. 60  is a cross-sectional view of the exemplary pavement cleat in  FIG. 55  taken along lines  16 - 16  in  FIG. 59 . 
           [0075]      FIG. 61  is a cross-sectional view of the exemplary pavement cleat in  FIG. 55  taken along lines  17 - 17  in  FIG. 59 . 
       
    
    
     DETAILED DESCRIPTION 
       [0076]    The exemplary embodiments of the present disclosure are described and illustrated below to encompass apparatuses and associated methods to secure a freight trailer in position at a loading dock while the trailer is loaded or unloaded. Of course, it will be apparent to those of ordinary skill in the art that the embodiments discussed below are exemplary in nature and may be reconfigured without departing from the scope and spirit of the present disclosure. However, for clarity and precision, the exemplary embodiments as discussed below may include optional steps and features that one of ordinary skill should recognize as not being a requisite to fall within the scope and spirit of the present disclosure. 
         [0077]    Referencing  FIGS. 1-6 , a first exemplary freight trailer stabilizer  100  includes an elevated king pin  102  operatively coupled to a gooseneck frame  104 . This gooseneck frame  104  is concurrently operatively coupled to cart frame  106  and a stiff leg assembly  108 . Operatively coupled to the cart frame  106  are repositionable jack assembly  110 , an axle  112  and wheels  114 , as well as a repositionable hook assembly  116 . As will be discussed in more detail hereafter, the repositionable hook assembly  116  is adapted to interact with a lock box  118  in order to secure the stabilizer  100  to the ground. In addition, the trailer stabilizer  100  includes a fifth wheel assembly  120  that is adapted to engage a king pin of a parked freight trailer to mount the stabilizer  100  to the trailer. Once mounted to the trailer, the hook assembly  116  may be utilized, as well as the repositionable jack assembly  110 , to provide support for the parked trailer. 
         [0078]    Referring to  FIGS. 7-11 , the gooseneck frame  104  comprises lower right and left tubular supports  130 ,  132  fabricated from rectangular tubular steel. The supports  130 ,  132  are welded at one end to a block C-shaped mount plate  134  that is mounted to the cart frame  106  using nut and bolt fasteners. At the opposing end, the supports  130 ,  132  are beveled at approximately forty-five degrees and welded to corresponding right and left side diagonal tubular supports  136 ,  138 . In order to reinforce the welded joints between the supports  130 ,  132 ,  136 ,  138 , cap plates  140  are mounted over and on the outside of the diagonal weld seams. Similar to the other supports, the diagonal supports  136 ,  138  are fabricated from rectangular tubular steel and include generally flat end surfaces (as opposed to being beveled). The diagonal supports operate to raise the height of the frame  104  and are coupled to corresponding right and left upper tubes  142 ,  144 . In particular, one end of the upper tubes  142 ,  144  has been beveled at approximately forty-five degrees and welded to corresponding ends of the right and left side diagonal tubular supports  136 ,  138 . As with the prior weld joints, cap plates  140  are mounted over and on the outside of the diagonal weld seams to reinforce the coupling between the supports  136 ,  138  and the upper tubes  142 ,  144 . An opposite end of each tube is generally flat (as opposed to being beveled) and is seated within a cavity  146  of the king pin plate  148 . 
         [0079]    The king pin plate  148  is fabricated from a rectangular plate having been formed to have a block C-shaped end  160 . Two holes  162 , which are generally centered as a group, extend through the front of the block C-shaped end  160 . Though not shown, these holes may accommodate one or more fluid lines (e.g., pneumatic, hydraulic, etc.) for coupling to jacks and motors associated with the stabilizer  100 . It is this C-shaped end  160 , which faces toward the cart frame  106 , that delineates the cavity  146  receiving the corresponding ends of the upper tubes  142 ,  144 . Each end of the upper tubes  142 ,  144  received within the cavity  146  may be machined so that the angle of the tubes (which taper inward) does not inhibit the entire end surface from contacting a vertical portion  164  of the block C-shaped end  160 . The block C-shaped end  148  cooperates with a generally rectangular portion  166  to comprise the king pin plate  148 . This rectangular portion  166  is positioned underneath and extends between the right and left upper tubes  142 ,  144 . Each of the right and left upper tubes  142 ,  144  is welded to the rectangular portion  166  in order to secure the king pin plate  148  to the tubes. Centered from side to side, the rectangular portion  166  includes a hole that receives the king pin  102 . In exemplary form, the king pin  102  is welded to the rectangular portion  166 . The king pin  102  extends through the rectangular portion  166  and faces toward the ground in order for the king pin to be available for coupling to a fifth wheel of a tractor (not shown). 
         [0080]    While not coupled to a tractor, the stabilizer  100  may be parked in a storage position. When parked in a storage position, the cart frame  106  of the stabilizer  100  does not bottom out to contact the ground. Rather, the stiff leg assembly  108  is operative to maintain the gooseneck frame  104  and king pin  102  at a height readily accessible by a tractor. 
         [0081]    In exemplary form, the stiff leg assembly  108  is a fixed position device that includes a stiff leg  180  operatively coupled to the gooseneck frame  104 . Specifically, the stiff leg  180  is mounted at one end to a stiff leg brace  182  that is mounted to and extends between the lower right and left tubular supports  130 ,  132 . In this exemplary embodiment, the stiff leg brace  182  is fabricated from angle iron and has a first horizontal aspect  184  and an upstanding vertical aspect  186 . The vertical aspect  186  includes at least one hole that is aligned with at least one corresponding hole extending through the stiff leg  180  so that nut a bolt fasteners mount the stiff leg to the stiff leg brace. In exemplary form, the stiff leg  180  is fabricated from block C-shaped metal stock and includes two upstanding, parallel flanges  188  that extend away from a base  190 . The stiff leg  180  is positioned to extend vertically so that the flanges  188  extend toward the cart frame  106 . In this manner, it is the base  190  that is adjacent and mounted to the upstanding vertical aspect  186  of the stiff leg brace  182 , while the opposite end (i.e., lower end) is adapted to be proximate the ground. 
         [0082]    The opposite, lower end of the stiff leg  180  is machined to remove a portion of the base  190 . In so doing, the lower end of the stiff leg  180  includes medial and lateral rectangular flaps  192 . These rectangular flaps  192  are really extensions of the two upstanding flanges  188  that remain at the lower end once a portion of the base  190  is removed. Each flap  192  includes a through hole in order to accommodate a nut and bolt fastener to secure a rubber block  194  to the stiff leg  180 . In exemplary form, the rubber block  194  includes a widthwise dimension to fit between the flaps  192  and a vertical, lengthwise dimension great enough to extend outward beyond the flaps when the block is mounted to the stiff leg  180 . It should be noted that materials other than rubber may be used for the block. Likewise, one may omit the block altogether and have the stiff leg itself contact the ground. 
         [0083]    Diagonal braces  200 ,  202  are concurrently mounted to the stiff leg  180  and the block C-shaped mount plate  134  in order to provide additional stability to the stiff leg. In exemplary form, the diagonal braces  200 ,  202  each comprise angle iron and are mounted to corresponding parallel flanges  188 . More specifically, one end of each diagonal brace  200 ,  202  is mounted to the outside of a corresponding flange  188 , while the opposite end of each diagonal brace  200 ,  202  is mounted to a bracket  204  inset within the block C-shaped mount plate  134 . In this exemplary embodiment, the flanges  188 , diagonal braces  200 ,  202 , and the brackets  204  include corresponding through holes that are aligned and receive bolts secured in place by nuts. In lieu of nut and bolt fasteners, the diagonal braces  200 ,  202  may be welded to the flanges  188  and the block C-shaped mount plate  134 . It should be noted that the block C-shaped plate includes a plurality of through orifices  204  that may accommodate one or more fluid lines (e.g., pneumatic, hydraulic, etc.) for coupling to jacks and motors associated with the stabilizer  100 . 
         [0084]    The block C-shaped plate  134  signifies the transition between the gooseneck frame  104  and the cart frame  106 . As will be described in more detail hereafter, the cart frame  106  has mounted to it the repositionable jack assemblies  110 , the axle  112 , and the repositionable hook assembly  116 . In order to accommodate these assemblies  110 ,  116  and axle  112 , the cart frame  106  includes right and left frame rails  210 ,  212  that are mounted to forward and rear cross-members  214 ,  216 . The frame rails  210 ,  212  are straight, block C-shaped and extend in parallel to one another so that the side flanges are directed toward the ground and the base faces upward. Specifically, the side flanges are oriented perpendicular to the base of the frame rails  210 ,  212 . These side flanges (on the inside that face one another) are welded to the front cross-member  214  in order to provide lateral support to the cart frame  106 . 
         [0085]    In this exemplary embodiment, the front cross-member includes a longitudinal pan  218  with integral front and rear flanges  220 . It is the top of the longitudinal pan and the front and rear flanges  220  that are welded to the inside flanges of the frame rails  210 ,  212 . The longitudinal pan  218  includes opposed vertical longitudinal walls  222  interposed by a bottom wall  224 . The bottom wall  224  includes a plurality of orifices  226 , where two of the orifices are surrounded by an upstanding ring  228  mounted to the bottom wall. As will be discussed in greater detail hereafter, the upstanding ring  228  is sized to be circumscribed by a coil spring that biases the fifth wheel assembly  120 . In this manner, the upstanding ring  228  inhibits lateral movement at the base of the spring. In exemplary form, the vertical longitudinal walls  222  are perpendicular to the bottom wall  224  and the entire bottom wall, as well as a portion of the longitudinal walls, is positioned vertically below the height of the frame rails  210 ,  212 . 
         [0086]    Also positioned vertically below the height of the frame rails  210 ,  212  are the axle  112  and the wheels  114 . In this exemplary embodiment, the axle  112  is mounted to the frame rails  210 ,  212  using corresponding pairs of U-bolts and nuts  240 . More specifically, the U-bolts  240  extend around the axle and are received through corresponding holes in the base of the frame rails  210 ,  212  and mounted thereto using the nuts. In order to increase the forward-to-rearward stability of the axle  112 , each frame rail  210 ,  212  includes a semi-circular cutout  242  formed at the bottom of each flange. These semi-circular cut-outs  242  are linearly aligned in the medial-lateral direction and operate to seat the axle  112  within the frame rails  210 ,  212 . As would be expected, the axle  112  is generally centered in the medial-lateral direction underneath the cart frame  106 . And the axle  112  interposes the forward and rear cross-members  214 ,  216 . 
         [0087]    In this exemplary embodiment, the rear cross-member  216  comprises a block C-shaped plate. The cross-member  216  includes a pair of vertical walls  246  perpendicular to a base wall  248 , where the vertical walls are parallel to one another. In exemplary form, the vertical walls  246  are closer to the ground than is the base wall  248 , where the height of the vertical walls  246  is substantially the same as the flanges for the frame rails  210 ,  212 . Specifically, the rear cross-member  216  is positioned in between the frame rails  210 ,  212  at the rear of each of each frame rail to be substantially flush with the rear of the frame rails. More specifically, the exposed ends of the flanges of the frame rails  210 ,  212  lie along the same plane as the exposed ends of the vertical walls  246 . When the frame rails  210 ,  212  are welded to the rear cross-member  216 , the flanges of the frame rails cap the longitudinal ends of the cross-member  216 . 
         [0088]    In order to complete the cart frame  106 , a number of vertical walls and elevated walls are mounted to the frame rails  210 ,  212 . In exemplary form, the cart frame  106  also includes right and left rear frame walls  250 ,  252  and right and left front frame walls  254 ,  256 . The right and left rear frame walls  250 ,  252  comprise a rectangular plate  260  having a perpendicular vertical flange  262  at one end and an associated rectangular wall  263  with its own perpendicular flange  265  at the opposite end. The plate  260 , flanges  262 ,  265 , and wall  263  all have the same vertical dimension and vertical ends that lie along the same corresponding planes (top and bottom). The plate  260  embodies the greatest width of the frame walls and includes a semicircular cut-out  264  and various through holes  266 . These cutouts  264  and holes  266  may be included to provide openings for various electrical wirings and/or fluid conduits. At the same time, these cutouts  264  and holes  266  may reduce the operating weight of the stabilizer  100  without sacrificing load bearing potential. 
         [0089]    The right and left rear frame walls  250 ,  252  are mounted to the top of the base of the frame rails  210 ,  212  and the base wall  248  of the rear cross-member  216 . Specifically, the frame walls  250 ,  252  are oriented so that the right angle corner formed by the intersection of the plate  260  and the wall  263  overlies a rear corner of a corresponding frame rail. In this manner, the plate  260  extends toward the front of the cart frame  106  so that its edge sits upon the outer edge of the base of a respective frame rail  210 ,  212 . Concurrent with this positioning, the wall  263  is positioned to overlay the rear edge of the cart frame  106 . This rear edge is cooperatively formed by the rear edge of the base of a corresponding frame rail  210 ,  212  in combination with outside edge of the base wall  248  of the rear cross-member  216 . When in this position, the right and left rear frame walls  250 ,  252  are welded to the frame rails  210 ,  212  and rear cross-member  216 . On the interior of each right and left rear frame walls  250 ,  252 , proximate the top upper corner where the plate  260  and wall  263  intersect, are tubular brackets  270 . As will be discussed in more detail hereafter, the tubular brackets  270  receive a hitch plate pivot shaft as part of the fifth wheel assembly  120 . 
         [0090]    At the rear of the cart frame  106 , a rear brace  280  extends between and is mounted to the wall  263  of both frame walls  250 ,  252 . The rear brace  280  comprises a vertical wall  282  that is perpendicularly oriented with respect to a horizontal extension  284  that extends from the vertical wall. The vertical wall  282  has a cut-out  286  in order to ensure the brace  280  does not contact a king pin from a parked trailer. In this exemplary embodiment, nut and bolt fasteners  288  are utilized to mount the rear brace  280  to the frame walls  250 ,  252 . It should also be noted that, as with the foregoing use of nut and bolt fasteners, the exemplary embodiment may utilize other means of fastening such as, without limitation, welding. 
         [0091]    Extending from the rear to the front of the cart frame  106 , are a pair of frame links  300 ,  302  that are positioned above and run in parallel with the frame rails  210 ,  212 . The right link  300  is concurrently mounted to the right rear frame wall  250  and right front frame wall  254 . Similarly, the left link  302  is concurrently mounted to the left rear frame wall  252  and left front frame wall  256 . Each link  300 ,  302  comprises angle iron that is mounted to a respective side&#39;s frame walls using nut and bolt fasteners  304 . In exemplary form, the right link  300  cooperates with the right frame rail  210  and the right front and rear frame walls  250 ,  254  to delineate a generally rectangular right side opening  306 . Likewise, the left link  302  cooperates with the left frame rail  212  and the left front and rear frame walls  252 ,  256  to delineate a generally rectangular left side opening  308 . As will be discussed in more detail below, these openings  306 ,  308  are utilized to link components of the repositionable jack assemblies  110 . 
         [0092]    The right and left front frame walls  254 ,  256  are mounted to the base of respective frame rails  210 ,  212 . More specifically, each frame wall  254 ,  256  comprises a block C-shape with a base wall  320  and two corresponding side walls  322  that expend parallel to one another. In this exemplary embodiment, the side walls  322  are perpendicular to the base wall  320  and are substantially shorter in width that the base wall. In order to mount the right and left front frame walls  254 ,  256  are mounted to the base of respective frame rails  210 ,  212 , the frame walls are oriented so that the base wall  320  is aligned with the outside edge of the frame walls. At the same time, the side walls  322  are positioned to sit on top of the base wall of the frame rails  210 ,  212 . More specifically, the forward most corner (where the side wall  322  and the base wall  320  intersect) of each frame wall  254 ,  256  is oriented to overly the outermost corner of a respective frame rail  210 ,  212 . In this orientation, the bottom edge of the side wall  322  sits upon the front top edge of a respective frame rail  210 ,  212 , while the base wall  320  sits upon the outer top edge of the same frame rail, and the frame walls  254 ,  256  are welded to the frame rails  210 ,  212 . 
         [0093]    In order to couple the remainder of the cart frame  106  to the gooseneck frame  104 , the cart frame also includes gussets  326  concurrently mounted to respective right and left front frame walls  254 ,  256  and the block C-shaped mount plate  134 . Specifically, the block C-shaped mount plate  134  includes two, spaced apart horizontal walls  330 ,  332  linked together by a vertical wall  334 . In exemplary form, the vertical wall is positioned adjacent to the forward most side wall  322  of each right and left front frame wall  254 ,  256  so that the ends of the block C-shaped mount plate  134  do not extend laterally beyond the base walls  320 . Likewise, the block C-shaped mount plate  134  is positioned so that the top edge of the right and left front frame walls  254 ,  256  is at the same vertical height as the upper horizontal wall  330 . When in this position, respective gussets  326  lie flush on top of the respective right and left front frame walls  254 ,  256  and the upper horizontal surface  330  of the block C-shaped mount plate  134 . In particular, the gussets  326  interpose the links  300 ,  302  and the right and left front frame walls  254 ,  256 . The gussets  326  are then mounted to the block C-shaped mount plate  134  using a first set of fasteners  340  and also mounted to the links  300 ,  302  using a second set of fasteners  342 . Complementary brackets  350  are also mounted to the forward most side wall  322  of each right and left front frame wall  254 ,  256  to wedge the block C-shaped mount plate  134  in between the gussets  326  and the brackets. By way of example, the brackets may be welded to the forward most side wall  322  of each right and left front frame wall  254 ,  256  or coupled thereto using any conventional fastener or fastener technique. Likewise, the brackets  350  are mounted to the block C-shaped mount plate  134  and may be mounted thereto by welding or using any conventional fastener (e.g., nut and bolts fasteners) or fastener technique. 
         [0094]    Referring to  FIGS. 12-16 , the repositionable hook assembly  116  is mounted to the cart frame  106  and adapted to interact with the lock box  118  in order to fasten the stabilizer to the ground. The lock box  118  is adapted to be mounted securely to the ground using ground spikes, nails, or other similar fasteners (not shown) so that the lock box is not readily repositionable. 
         [0095]    In exemplary form, the lock box  118  includes corresponding right and left side ramps  400 ,  402  that cooperate with corresponding front and rear ramps  404 ,  406  to provide a frustopyramidal structure. More specifically, the ramps  400 ,  402  are comprised of generally flat metal plates having an upper lip  408  opposite a substantially wider base  410 . The front and rear ramps  404 ,  406  comprise generally flat metal plates but for angled flanges  411  at opposing lateral ends. The angle of the flanges  411  is adapted to match the angle of incline of the right and left side ramps  400 ,  402 . Moreover, the flanges  411  include orifices  412  that overlap countersunk orifices  414  formed through the lateral sides of the right and left side ramps  400 ,  402 . More specifically, the medial and lateral sides of the right and left side ramps  400 ,  402  overly the flanges  411  of the front and rear ramps  404 ,  406  so that the orifices  412 ,  414  overlap in order to receive nut and bolt fasteners to mount the ramps to one another. When assembled, the ramps  400 ,  402 ,  404 ,  406  provide an incline on all four sides without appreciable seams for large objects (such as snow plows) to catch the seams and rip apart the ramps. In addition, the lips  408  are oriented in parallel with the ground when the ramps  400 ,  402 ,  404 ,  406  are assembled in order to provide overhead protection for components on the interior of the lock box that are not intended to be contacted by the hook assembly  116 . 
         [0096]    The interior of the lock box  118  includes an anchor  420  having one or more holes (not shown) to receive ground spikes, nails, or other similar fasteners (not shown) in order to secure the lock box to the ground. In exemplary form, the anchor  420  comprises an elongated rectangular plate  422  having upstanding medial and lateral walls  424 ,  426 . Each wall  424 ,  426  is oriented generally perpendicular to the plate  422  and is beveled at its ends to match the intended incline of the front and rear ramps  404 ,  406 . The medial and lateral walls  424 ,  426  include four identical cutouts  430  having rounded, cupped shape (and may be semicircular) to act as a seat in order to receive a cylindrical anchor bar  432 . The cutouts  430  are generally evenly spaced apart and cooperate with anchor bar orifices  438  extending through the right and left side ramps  400 ,  402  in order to secure the cylindrical anchor bars  432  in position, but also allow the anchor bars to axially rotate. Each anchor bar  432  includes an outer cylinder  434  having a length at least long enough to laterally span corresponding cutouts  430 . The outer cylinder  434  may be machined to include cylindrical extensions  436  from each end that are of a smaller diameter. Alternatively, the outer cylinder  434  may have an internal cylindrical cavity that is occupied by a cylindrical insert  436  having an overall length long enough to extend axially outward from the outer cylinder. In either circumstance, the cylinders  434 ,  436  are mounted to one another so that rotation of one results in rotation of the other. A trap door  440  is mounted to three of the four outer cylinders  434 . 
         [0097]    Interposing the four cutouts  430  are three identical cutouts  444  having a generally arcuate path with a flat end. The three cutouts  444  receive corresponding ends of each trap door  440 . In this manner, as the outer cylinder  434  is rotated, so too is the trap door rotated, thus the arcuate path of the cutout  444 . In exemplary form, the lengthwise dimension of each trap door  440  approximates the horizontal distance between adjacent outer cylinders  434 . Likewise, the widthwise dimension of each trap door  440  approximates the lateral distance between the medial and lateral walls  424 ,  426 . In this way, the trap door  440  attempts to prohibit foreign debris of problematic size from entering the lock box  118  and inhibiting its operation. 
         [0098]    For the three outer cylinders  434  that includes a trap door  440 , a spring  446  (e.g., a torsion spring) is mounted to the smaller cylinder  436  and is operative to bias the trap door in the horizontal, blocking position (see  FIG. 13 ). Thought not necessary, at least one of the medial and lateral walls  424 ,  426  includes a stop  450  mounted to the anchor  420  that is adapted to engage a spring, such as a torsion spring, in order cooperate with the spring to bias the trap door  440  to the blocking position. But, when contacted by the hook as will be described hereafter, the hook is operative to overcome the bias and force the trap door downward so the hook can couple to a corresponding outer cylinder  434 . 
         [0099]    The repositionable hook assembly  116  includes an airbag  460  operatively coupled to a linear rod  462 . The linear rod  462  includes a fitting  464  having a ball joint that receives a clevis pin  466  in order to transfer motion from the airbag  460  to a pivot shaft  468 . The pivot shaft  468  includes a pivot arm  470  having a hole  472  therethrough. This hole  472  receives the clevis pin  466 , where motion of the clevis pin is transferred to the pivot shaft  468  by way of the pivot arm  470 . Specifically, the airbag  460  is operative to expand (i.e., inflate) and turn the pivot arm  470  and pivot shaft  468  in the clockwise direction that is operative to lower a hook  480 . Alternatively, the airbag  460  may be omitted and the hook  480  may be lowered using gravity. But the hook assembly  116  also includes a second airbag  482  having a linear rod  484  and a fitting  486  with a ball joint to receive the clevis pin  466 . This second airbag  482  is operative to expand (i.e., inflate) and turn the pivot arm  470  and pivot shaft  468  in the counterclockwise direction to raise the hook  480  or retain the hook in a raised position. Both of the airbags  460 ,  482  are mounted to a bracket  490  that is mounted to the top of the rear cross-members  216 . Specifically, the bracket  490  includes a pair of holes  492  that receive nut and bolt fasteners to mount the bracket to the rear cross-member. In exemplary form, the bracket  490  includes a pair of opposed flanges  494 ,  496  having corresponding holes that receive nut and bolt fasteners to couple the airbags  460 ,  482  to the respective flanges  494 ,  496 . Interposing the flanges  494 ,  496  is a section of angle iron  498  that includes the pair of holes  492  used to mount the bracket  490  to the rear cross-member  216 . A pair of shaft brackets  500  is utilized to mount the pivot shaft  468  to the rear cross-member  216  and the rectangular wall  263  of the right and left rear frame walls  250 ,  252 . 
         [0100]    The hook  480  is mounted to the pivot shaft  468  so that rotation of the pivot shaft results in arcuate movement of the hook, generally in an upward and downward direction. In this exemplary embodiment, the hook  480  comprises mirror image hook halves  510 ,  512 . Each hook half  510 ,  512  comprises a first bar stock section  514  having a rounded proximal end  516  and a through orifice allowing throughput of the pivot shaft  468 . Specifically, the bar stock section  514  is welded to the pivot shaft  468  and gussets  518  are concurrently welded to the bar stock section and the pivot shaft. A distal end of the bar stock section  514  includes a bend that transitions into a second bar stock section  520 . Alternatively, the bar stock sections  514 ,  520  may be separate pieces that are welded together. This second bar stock section  520  includes a distal bend and comprises a hook section  524 . In exemplary form, the hook sections  524  from each hook half  510 ,  512  are welded together to create a two-ply end hook  530 . 
         [0101]    Referring to  FIGS. 17-20 , the fifth wheel assembly  120  comprises two primary subassemblies, the tilt subassembly  550  and the pivot subassembly  560 . The tilt subassembly  550  includes a tilt plate  570  having a generally rectangular shape, but for a tapered cutout  572  that leads into a king pin cavity  574 . The king pin cavity  574  is adapted to be occupied by the king pin of a parked freight trailer. In this exemplary embodiment, the king pin cavity  574  is partially defined by the tilt plate  570  and partially defined by a king pin block  576  mounted to the underside of the tilt plate. The lateral sides  578  of the tilt plate  570  are formed by lateral extensions of the plate having been rounded over to form perpendicular flanges. A frame  580  is mounted to the underside of the tilt plate  570  and includes lateral and vertical cross members  582 ,  584 . The frame also includes a front plate  586  that spans a proximal portion of the tilt plate  570 , as well as distal plates  588  that span between angled frame members  590  and the lateral sides  578 . The angled frame members  590  lie along the cutout  572  in order to reduce wear upon the tilt plate where the king pin from the freight trailer would otherwise contact. 
         [0102]    As will be described in more detail hereafter, the tilt plate  570  is repositionable with respect to the pivot subassembly  560 . In particular, parallel, vertical cross members  584  each include extensions  594  through which holes are bored to receive a tilt shaft  596 . The sides  578  of the tilt plate  570  also include extensions  598  through which holes are bored to receive the tilt shaft  596 . In this exemplary embodiment, the tilt shaft  596  is welded to the extensions  594 ,  598  so that rotation of the shaft results in corresponding movement of the tilt plate  570 . Interposing the extensions  594 ,  598  are a pair of brackets  600  that are mounted to the pivot subassembly  560 . These brackets  600  allow the tilt shaft  596  to rotate so that tilting of the tilt plate  570  is possible with respect to the pivot subassembly  560  is possible, but to a limit. The brackets  600  each have corresponding holes adapted to overlap with holes in the pivot subassembly and receive nut and bolt fasteners to repositionably mount the tilt subassembly  550  and the pivot subassembly  560 . 
         [0103]    Referring to  FIGS. 21-23 , the pivot subassembly  560  includes a right and left side pivot tubes  610 ,  612  fabricated from rectangular metal tubing. Each tube  610 ,  612  includes corresponding holes  614  that overlap with the holes  602  in the brackets to receive nut and bolt fasteners to repositionably mount the tilt subassembly  550  and the pivot subassembly  560 . At the rear of each tube  610 ,  612  are a pair of circular openings that allow throughput of a pivot shaft  616 . In exemplary form, the pivot shaft  616  extends through each tube  610 ,  612  a predetermined distance and is welded to each tube. At the front of each tube  610 ,  612  is a cross-tube  620  that is positioned between the tubes and is welded thereto. By way of example, the tubes  610 ,  612 ,  620 , and the shaft  616  form a rectangle. It should be noted that the extension of the pivot shaft  616  extending beyond the tubes  610 ,  612  is at least partially received within the tubular brackets  270  of the cart frame  106  to allow the pivot subassembly  560  to pivot with respect to the cart frame. Finally, each tube  610 ,  612  includes a rocker  626  mounted to the front of each tube on the opposite side as the brackets  600 . The rocker  626  comprises arcuate projection  628  that is received within a corresponding bracket of the repositionable jack assemblies  110  to that the rocker can move in a rocking motion when the pivot subassembly  560  pivots with respect to the cart frame  106 . 
         [0104]    Referring to  FIGS. 24-29 , the repositionable jack assembly  110  is operative to deploy a pair of jacks  650  mount on the medial and lateral sides of the cart frame  106  to at least partially support some of the weight at the front of the freight trailer and provide greater lateral stability than is possible using the freight trailer&#39;s landing gear. In this exemplary embodiment, the jacks  650  are screw jacks. Those skilled in the art are familiar with the operation of screw jacks and therefore the internal structure and operation of screw jacks will not be discussed for purposes of brevity. 
         [0105]    Each screw jack  650  includes a telescopic screw jack leg  652  mounted to front and rear brackets  654 ,  656 . Each bracket  654 ,  656  comprises an I-beam construction with a first section  658  that is welded to the jack leg and extends laterally outward therefrom. A second I-beam section  660  is welded to the first section  658  and is oriented perpendicularly with respect to the first section and extends through a corresponding side opening  306 ,  308  in the cart frame  106 . The end of the second section  660  not mounted to the first section  658  includes a vertical end plate  662  that spans between the top and bottom of the I-beam on one side of the vertical wall of the I-beam. The vertical end plate is welded in position and includes a plurality of orifices  664  for mounting to a side plate  666 . 
         [0106]    The side plate  666  extends parallel with the plane of the opening  306 ,  308  and includes a vertical wall  680  that is rounded over to provide a pair of vertical flanges  682 ,  684  that are oriented generally perpendicular to the vertical wall. Each flange  682 ,  684  is mounted to at least one follower  686  that follows a respective section of vertical track  688  mounted to a vertical flange  690  of one of four frame walls (right rear frame wall  250 , left rear frame wall  252 , right front frame wall  254 , left front frame wall  256 ). In this fashion, as the screw jack leg  652  is extended and eventually contacts the ground, the screw jack leg  652  will operate to push upward on the jack, which will push upward on the brackets  654 ,  656 , thereby pushing upward on the side plate  666  so the side plate travels vertically in a straight path as dictated by the followers  686  following the track  688 . 
         [0107]    The side plate  666  also includes a third flange  687 , also rounded over from the vertical wall  680 , that extends horizontally toward the center of the cart frame  106 . This flange  687  has mounted to it a guide track  700  that receives the arcuate projection of the rocker  626  so the pivot subassembly  560  can rock with respect to the side plate  666 . 
         [0108]    Underneath the third flange  687  is a welded gusset  701  that contacts a cross-plate  702 . The cross-plate  702  includes a horizontal plate  704  that extends laterally (i.e., medial to lateral direction) in between opposing side plates  666  and is spaced apart from the third flange  687  by the gusset  701 . The cross-plate  702  also includes a vertical plate  706  that extends perpendicularly from the horizontal plate  704  at a front edge of the horizontal plate. In exemplary form, the gusset  701  is welded to the horizontal plate  704 , while the end of the vertical plate  706  is welded to the underside of the third flange  687 . 
         [0109]    The side plate  666  also includes a lateral orifice  710  to allow throughput of a rotating shaft. In this exemplary embodiment, the rotating shaft comprises a drive shaft  712  coupled to a first jaw coupling  714 . This first jaw coupling  714  is coupled to a second jaw coupling  716 , which is itself coupled to a screw jack shaft  718  that extends through the jack leg  652 . An opposite end of the drive shaft  712  is coupled to a clutch  720 . The clutch  720  receives an output shaft  722  from a gearbox  724  coupled to an air motor  726 . In exemplary form, the gearbox  724  is mounted to the horizontal plate  704 , while the air motor  726  is mounted to the gearbox. The other components such as the drive shaft  712 , the jaw couplings  716 ,  718 , the clutch  720 , and the output shaft are  722  suspended in the air. 
         [0110]    Underneath the cross-plate  702  are two upstanding rings  730  that are vertically aligned with the two upstanding rings  228  mounted to the forward cross-member  214 . Circumscribing these upstanding rings  228 ,  730  are two coil springs  732 . In this manner, the repositionable jack assembly  110  floats on top of the two coil springs when the screw jack legs  652  are raised. This means that the amount of force required to position the fifth wheel assembly  120  underneath a parked trailer is only as great as the bias exerted by the springs. But after the stabilizer  100  is coupled to the parked trailer and the jack assembly is operative to extend the jack legs  652 , it is the jack legs that are bearing the weight of the fifth wheel assembly  120  and at least a portion of the weight of the parked freight trailer. 
         [0111]    In order to power the repositionable jack assembly  110  and the repositionable hook assembly  116 , the exemplary stabilizer  100  uses pneumatic power. Those skilled in the art are familiar with pneumatic power. Accordingly, for purposes of clarity, the pneumatic lines running to the air motor  726  and airbags  460 ,  482  have been omitted. Nevertheless, the stabilizer  100  includes an on-board fluid tank  740  that may be used to store compressed air to power the repositionable jack assembly  110  and the repositionable hook assembly  116 . In this exemplary embodiment, the fluid tank  740  is mounted to the front ends of the right and left frame rails  210 ,  212  using brackets  742  and nut and bolt fasteners. It should also be noted that the fluid tank  740  may be supplemented by an air supply from a tractor or hustler. While glad-hands have not been shown in the drawings, it is understood that the instant stabilizer  100  may include pneumatic lines linking the fluid tank  740  to a glad-hand connection. Alternatively, the stabilizer may include pneumatic lines that by-pass the fluid tank and connect optionally to a glad-hand. In such a circumstance, when a by-pass approach is utilized, the stabilizer need not be supplied with a fluid tank  740 . 
         [0112]    The exemplar stabilizer  100  is adapted to be coupled to a tractor or a hustler via the king pin  102 . While not required, the stabilizer may also couple to one or more power supplies on the tractor or hustler to power one or more of the foregoing assemblies. In exemplary form, the parked freight trailer would already be parked over the lock box  118 . After the stabilizer  100  is coupled to the tractor or hustler, the stabilizer is backed under a parked trailer at a loading dock so that the repositionable hook assembly  116  first goes under the trailer, followed by the rear of the cart frame  106  in order for the fifth wheel assembly  120  to capture the king pin of the parked trailer. In exemplary form, the fifth wheel assembly  120  include an automatic lock that capture the king pin of the parked trailer and does not allow the stabilizer to be disengaged without affirmatively disengaging the lock. 
         [0113]    After the stabilizer  100  captures the king pin, the repositionable hook assembly  116  is engaged to lower the hook  480  by supplying air to inflate the airbag  460 . Depending upon the dimensions of the freight trailer and the position of the lock box  118 , the hook  480  may contact a trap door  440  and fall in between anchor bar  432 . Thereafter, the stabilizer may be repositioned forward to lock the hook  480  within the lock box  118 . Alternatively, the hook  480  may contact one of the anchor bars  432 , at which time the stabilizer is move slightly rearward so the hook rides upon the anchor bar and then drops down onto the next trap door  440 . Thereafter, the stabilizer is pulled slightly forward to lock the hook  480  within the lock box  118 . 
         [0114]    After the repositionable hook assembly  116  has been positioned to lock the hook  480  within the lock box  118 , the repositionable jack assembly  110  is engaged to deploy the jacks. In exemplary form, air is supplied to the air motor  726 , which in turn turns gears within the gearbox  724  to correspondingly rotate the output shaft  722 . The drive shaft  712  is driven by the output shaft, interposed by the clutch  720 , and operates to drive the screw jack legs  652  downward. If an impediment is sensed, such as a wood block under one of the screw jack legs, but not under the other screw jack leg, the clutch will engage to disallow further rotation of the screw jack until the resistance of both jack legs is approximately the same. It should be noted that the stabilizer, while able to accommodate the entire weight of a fully loaded trailer at the front of the trailer, is more often utilized to share the load of the loaded trailer with the trailer&#39;s landing gear. As soon as the repositionable jack assembly  110  has been positioned to transfer some of the trailer&#39;s load onto the stabilizer  100 , dock personnel are notified that it is appropriate to load or unload the parked trailer. This may be done with manually operated signals or may be accomplished via automated signals associated with the stabilizer that send a signal to dock personnel as soon as the repositionable hook assembly  116  and the repositionable jack assembly  110  have been successfully deployed. 
         [0115]    To remove the stabilizer, a similar process is followed in the opposite sequence. First, the repositionable jack assembly  110  is disengaged, followed by disengaging the repositionable hook assembly  116 . Thereafter, the stabilizer  100  is removed from the parked trailer and put in a storage position or moved underneath another parked trailer. 
         [0116]    Referring to  FIG. 30 , while the foregoing exemplary embodiment has been explained using pneumatic power, an alternate exemplary embodiment for a trailer stabilizer is identical to the foregoing exemplary embodiment, except that the power supply, associated motors, and airbags are exchanged for hydraulic power and hydraulic cylinders. In exemplary form, the on-board fluid tank  740  of the stabilizer is at least partially filled by a glycol liquid (e.g., propylene glycol). The fluid tank  740  includes at least one outlet to a liquid supply line in order to supply glycol from inside the tank to the supply lines and to convey glycol back into the fluid tank when appropriate (such as when the hook is raised and/or when the jacks are raised. In this alternate exemplary embodiment, the jacks of the repositionable jack assembly  110  include hydraulic cylinders having a piston that extends by supplying glycol to the cylinder. Moreover, the cylinders are also operative to retract the piston when glycol is added to the other side of the seal within the cylinder. Moreover, the airbags  460 ,  482  of the repositionable hook assembly  116  are replaced by a single hydraulic cylinder having a piston that extends and retracts based upon the glycol supplied to the cylinder. While it is the glycol supplying the fluid to reposition the piston with respect to the cylinder, this alternate exemplary embodiment used compressed air to force the glycol through the supply lines. 
         [0117]    Referencing  FIGS. 31 and 32 , a further alternate exemplary embodiment  800  of a trailer stabilizer is identical to the first exemplary trailer stabilizer  100 , but for wheel brakes  802 . In exemplary form, the pivot shaft  468  of the repositionable hook assembly  116  is lengthened in the medial and lateral directions to extend outward to behind the wheels  114 , thus forming a lengthened shaft  468 ′. Corresponding brackets  804  are mounted to the pivot shaft  468 ′ right behind each wheel  114  and each include a pair of plates  806  that sandwich a rubber block  808  therebetween. The plates  804 ,  806  may be mounted to the rubber block  808  using any acceptable technique to retain the rubber block. In this exemplary embodiment, the plates  804 ,  806  include a through hole that is aligned with a through hole of the rubber block so that nut and bolt fasteners are utilized to secure the block to the plates. 
         [0118]    In exemplary form, when the hook is in the retracted position (hook is up and disengaged from the lock box), the rubber block does not contact the wheels  114 . But when the hook is in the extended position (hook is down and engaging the lock box) the rubber block comes in contact with the rear of the wheel  114 . In this manner the rubber block acts as a stop to inhibit the wheels  114  from rotating when the hook is in the extended position. Those skilled in the art will realize that the brakes  802  may be employed by repositioning the hook even in the case where the hook has no lock box to interface with. 
         [0119]    Referring to  FIGS. 33-44 , a second exemplary freight trailer stabilizer  900  is essentially the same as the first exemplary freight trailer stabilizer  100 . However, the second exemplary trailer stabilizer  900  includes a different repositionable hook assembly  902  (as opposed to the repositionable hook assembly  116 ), the wheel brakes  802  discussed previously, a control system, and a dock notification and communication system. Because the trailer stabilizer includes almost all of the same structure and features as discussed with respect to the first exemplary freight trailer stabilizer  100 , a detailed recitation of the features in common has been omitted for purposes of brevity. Accordingly, unless noted otherwise, the second exemplary freight trailer stabilizer  900  makes use of the same structure and features as the first exemplary freight trailer stabilizer  100 . 
         [0120]    Referring to  FIGS. 33-37 , the second exemplary freight trailer stabilizer  900  includes a different repositionable hook assembly  902 . In exemplary form, this different repositionable hook assembly  902  is mounted to the cart frame  106  and adapted to interact with a lock box  920  in order to fasten the stabilizer  900  to the ground. The lock box  920  is adapted to be mounted securely to the ground using ground spikes, nails, or other similar fasteners (not shown) so that the lock box is not readily repositionable. 
         [0121]    In exemplary form, the lock box  920  includes a corresponding right side ramp (not shown) and a left side ramp  932  cooperating with corresponding front and rear ramps  934 ,  936  to provide a frustopyramidal structure. The sides and top of the frustopyramidal structure are partially open and include a series of slots  940  that are sized to receive a drop bar of the repositionable hook assembly  902  in order to secure the repositionable hook assembly (and thus the stabilizer  900 ) to the ground. In particular, the slots  940  are incrementally spaced apart and inclined away from the stabilizer  900  so that once the drop bar is received initially within one of the slots  940 , the trailer stabilizer may be slightly moved forward (away from the lock box  920 ) so that the drop bar falls down completely within a particular slot and thereafter sits upon the left and/or right side ramps. When the drop bar is captured within one of the slots  940 , only minimal movement (forward or backward) of the stabilizer  900  is possible. 
         [0122]    In exemplary form, the lock box  920  is fabricated from metal plate. However, in view of the aforementioned and following disclosure, those skilled in the art will readily understand that the described materials and techniques for forming the lock box comprises only a small subset of the materials and techniques that may be available to form a lock box  920 . By way of example, the front and rear ramps  934 ,  936  are comprised of generally flat metal plates having a trapezoidal configuration. These plates  934 ,  936  are welded to a single, formed metal piece that comprises the right and left side ramps  932 . In order to form the right and left side ramps  932  from a single piece of metal plate, a flat metal plate is stamped to create a series of cut-outs that will ultimately form the slots  940 , as well as the general outline of the finished piece. After the plate has been stamped, the plate is bent to have a three-dimensional shape embodying the respective right and left sides interconnected by the top side. The bending of the plate is operative to convert the cut-outs into the slots  940 . 
         [0123]    Alternatively, the lock box  920  may be fabricated so the front and rear ramps  934 ,  936  are integrally formed with a portion of the right and left side ramps. In such a circumstance, a forwardmost and rearwardmost portion of the right and left side ramps  932  are integrally formed with the front and rear ramps  934 ,  936 , thereby resulting in a three dimensional cap that may be welded to or otherwise fastened to the remaining portion(s) that defines the remainder of the left and right side ramps  932  and slots  940 . 
         [0124]    In order to secure the lock box  920  to the ground, a pair of pavement ties  942  are secured to opposite sides of the lock box. These pavement ties  942  may be comprised of any permanent fastener that is securely mounted to the ground and can withstand a predetermined amount of force. By way of example, the pavement ties are metal bands that are bolted to the ground using an embedded anchor (not shown). The pavement ties  942  may be welded, bolted, or otherwise fastened to the lock box  920 . In exemplary form, the pavement ties  942  are removably mounted to the lock box  920  in order to allow the lock boxes to be removed for clearing operations including, without limitation, snow plowing. 
         [0125]    The repositionable hook assembly  902  also includes a repositionable hook  948  that uses many of the same components as the first exemplary embodiment. In this case, the hook  948  is mounted to the pivot shaft  468  so that rotation of the pivot shaft results in arcuate movement of the hook, generally in an upward and downward direction. In this exemplary embodiment, the hook  948  comprises mirror image hook halves  950 ,  952 . Each hook half  950 ,  952  comprises a bar stock section having a rounded proximal end  956  and a through orifice allowing throughput of the pivot shaft  468 . Specifically, the bar stock sections  954  are welded to the pivot shaft  468  and gussets  958  are concurrently welded to the bar stock section and the pivot shaft. A distal end of the bar stock section includes an enlarged head  959  having a triangular opening  960 . This triangular opening  960  accommodates a floating cylinder  961  that has a pair of washers  962  to inhibit substantial lateral movement of the cylinder. In other words, the washers operate to retain the cylinder  961  ends within the triangular openings  960  and thus have the cylinder spanning between the hook halves  950 ,  952 . In this context, the term “floating” refers to the triangular openings  960  being considerably larger than the cross-section of the cylinder  961 , which provides play of the cylinder within the openings as defined by the bounds of the openings. Finally, the hook halves  950 ,  952  are also coupled to one another using a cross-member  966  to reduce torsion between the hook halves. 
         [0126]    Because the operation of the repositionable hook assembly  902  in terms of raising and lowering the hook  948 , and the structure utilized to raise and lower the hook, is substantially the same as the structure utilized in the first exemplary embodiment, a duplication discussion has been omitted for purposes of brevity. 
         [0127]    Referring to FIGS.  33  and  39 - 43 , the second exemplary freight trailer stabilizer  900  includes a control system and a dock notification and communication system that work in tandem to impact the operation of the trailer stabilizer. The control system includes a control circuitry  970  housed within a control panel  972 , which itself includes a visual display  974  and operator controls  976 . In exemplary form, the visual display comprises a light that can be selectively illuminated, as well as illuminated in different colors. By way of example, the visual display  974  of the control panel  972  comprises a bulb housing containing a green light emitting diode (LED) and a red LED. As will be discussed in more detail hereafter, this structure provides for three options: (1) no light is illuminated; (2) the green LED is illuminated; and, (3) the red LED is illuminated. 
         [0128]    The control panel  972  receives inputs from a plurality of different sensors. In exemplary form, the control system includes seven different sensors that provide indications about the position of various components of the second exemplary freight trailer stabilizer  900 . A first of these sensors  980  is a king pin sensor. This sensor  980  comprises a proximity sensor that is positioned adjacent to a biased plunger (not shown) that extends into the portion of the king pin cavity  574  defined by the king pin block  576  (see  FIG. 18 ). In this manner, whenever a king pin of a parked trailer is within the king pin block  576 , the king pin will contact the biased plunger and displace the plunger in order that the proximity sensor  980  senses the displaced plunger and sends a signal to the control circuitry  970  indicative of the king pin being within the king pin block. Conversely, when no king pin of a parked trailer is within the king pin block  576 , the plunger is biased away from the proximity switch  980  and the switch does not send a signal to the control circuitry  970  indicative of the king pin being within the king pin block. In addition to monitoring the position of a king pin, the control system also monitors the position of the jacks  650  of the repositionable jack assembly  110 . 
         [0129]    In exemplary form, the right side jack  650  includes a proximity sensor  984  mounted to the stationary portion of the screw jack leg  652  that detects when the boot (the portion of the jack contacting the ground) is fully raised. Likewise, the left side jack  650  includes a proximity sensor  986  mounted to the stationary portion of the screw jack leg  652  that detects when the boot (the portion of the jack contacting the ground) is fully raised. In this manner, both sensors  984 ,  986  are operative to communicate with the control circuitry  970  and indicate when each of the jacks  650  is fully raised. As will be discussed in greater detail hereafter, when the control circuitry receives signals from both sensors  984 ,  986  that the jacks  650  are fully raised, the control circuitry  970  turns off an electric motor  726  operatively coupled to the jacks. And the control system  970  also tracks when the jacks  650  are lowered to contact the ground. 
         [0130]    In exemplary form, the drive shaft  712  engaging the right side jack  650  includes a magnet (not shown) being mounted thereto. The magnetic proximity sensor  985  is operative to detect the magnet as it rotates past the sensor. As discussed previously, a clutch  720  is coupled to the drive shaft  712  (see  FIG. 25 ) so that when the jacks  650  are deployed, presuming one jack hits the ground before the other, the drive shaft to the jack hitting first will discontinue rotation, while the drive shaft to the other jack will continue to rotate until that jack reaches the ground. The sensor  985  sends a signal to the control circuitry  970  when the magnet is detected, as occurs once for each rotation of the drive shaft  712 . But when the right side jack  650  reaches the ground, the drive shaft  712  no longer rotates. Based upon preprogrammed logic, the absence of a signal from the sensor  985  for a predetermined period of time is identified as the right side jack having reached the ground. Similarly, the drive shaft  712  driving the left side jack  650  also includes a magnet permanently mounted thereto and detectable by the left side magnetic proximity sensor  987 . The sensor  987  sends a signal to the control circuitry  970  when the magnet is detected, as occurs once for each rotation of the drive shaft  712 . But when the left side jack  650  reaches the ground, the drive shaft  712  no longer rotates. Based upon preprogrammed logic, the absence of a signal from the sensor  987  for a predetermined period of time is identified as the left side jack having reached the ground. After the control circuitry  970  determines that both jacks have reached the ground, a power source is disconnected from the motor  726 , in this case an electric motor. 
         [0131]    The control circuitry  970  is also communicatively coupled to a pair of sensors  988 ,  990  that indicate the position of the repositionable hook assembly  902 . In exemplary form, a pair of proximity sensors  988 ,  990  are mounted to the bracket  490  (see  FIG. 14 ) of the repositionable hook assembly  902  in order to track the relative position of the pivot arm  470 . When the pivot arm  470  is rotated toward the airbag  460  the hook  948  is raised, while rotation of the pivot arm toward the second airbag  482  is operative to lower the hook. In this manner, a signal from the first hook sensor  988  to the control circuitry  970  indicates the hook  948  is raised, while a signal from the second hook sensor  990  to the control circuitry  970  indicates the hook is lowered (or engaged with the lock box  920 ). As will be discussed in more detail hereafter, the control circuitry uses the output from these sensors  988 ,  990  to control outputs to various output devices. 
         [0132]    Referring to  FIGS. 39-44 , the dock notification and communication system interacts with the control system and vice versa to provide visual indications including, without limitation, that the stabilizer  900  is properly aligned, the jacks are or are not deployed, the hook is or is not deployed, the trailer is safe or not yet safe to load, and the parked trailer has or has not been loaded/unloaded. 
         [0133]    Referring to  FIGS. 33-44 , the dock notification and communication system includes a repositionable arm  1000  that is mounted to the cart frame  106 . The repositionable arm  1000  includes a sensor and transmitter housing  1002  that houses a pair of infrared (IR) transmitters  1004 ,  1006 , and an infrared receiver  1008 . In this exemplary embodiment, the IR transmitters  1004 ,  1006  use different frequencies to avoid information or signal crossing. An elongated, rectangular tubular pole  1012  is mounted to the housing  1002  at one end and pivotally mounted to the cart frame  106  at an opposite end. Specifically, the cart frame  106  includes a left rear frame wall  252  to which a pair of brackets  1016 ,  1018  are mounted. The first bracket is mounted closer to the jacks  650  and has mounted to it a damper  1020 , in this case a coiled spring. The coiled spring  1020  is also mounted to the tubular pole  1012  and operates to bias the pole to the extended position (extending laterally from the stabilizer  900 ). As will be discussed in more detail hereafter, the pole  1012  floats with respect to the frame  106  when the stabilizer  900  is parked under the trailer and not coupled to a hustler. The second bracket  1018  is mounted closer to the hook  948  and extends laterally outward from the left side of the frame  106 . The bracket includes opposing top and bottom parts that operate to sandwich an end of the pole therebetween. In exemplary form, the pole  1012  and bracket parts  1018  are fabricated from metal and a plastic bushing  1024  interposes the bracket parts and the pole to reduce friction. Each of the pole  1012 , the bracket parts  1018 , and the plastic bushings  1024  include an aligned through hole that receives a through pin  1028 . In this manner, the pole  1012  and housing  1002  are able to pivot, about the pin, with respect to the stabilizer frame  106 . 
         [0134]    A pneumatic cylinder  1030  is concurrently mounted to the pole  1012  and the stabilizer frame  106 . Specifically, a bracket  1032  is mounted to the left rear corner of the frame  106  and includes a coupling  1034  mounted to the cylinder  1030  that allows the cylinder to pivot about the coupling. The cylinder includes a piston  1033  that is coupled to the pole  1012  by way of a bracket  1038 . The cylinder  1030  includes fittings  1040  operative the provide fluid delivery to the cylinder to move the piston inward and outward with respect to the cylinder. As will be discussed in more detail hereafter, the cylinder  1030  is operative to move the pole  1012  and housing  1002  between a lateral position (extending laterally out from the left side of the frame) and a storage position where the pole pivots approximately ninety degrees toward the rear of the stabilizer  900  to fold into the side and position the housing rearward. 
         [0135]    The dock notification and communication system includes an exterior dock cabinet  1050  that houses a pair of IR receivers  1052 ,  1054  that are adapted to receive the IR signals sent from the IR transmitters  1004 ,  1006  housed within the transmitter housing  1002  of the repositionable arm  1000 . As discussed previously, the first IR transmitter  1004  is transmitting at a first frequency and is oriented to align with the first IR receiver  1052 . Similarly, the second IR transmitter  1006  is transmitting at a second frequency and is oriented to align with the second IR receiver  1054 . In order to increase the likelihood of alignment, the IR transmitters  1004 ,  1006  have a predetermined spacing, while this predetermined spacing is maintained by the dock cabinet  1050  when mounting the IR receivers  1052 ,  1054 . Moreover, the configuration of a triangular pattern is also maintained by the dock cabinet  1050 . In the case of the transmitter housing  1002  associated with the stabilizer  900 , the apex comprises an IR receiver  1008 , while the two lower parts comprise the IR transmitters  1004 ,  1006 . This same orientation is mirrored by the dock cabinet  1050  by orienting an IR transmitter  1056  at the apex to communicate to the IR receiver  1008 , while the two lower parts comprise the IR receivers  1052 ,  1054  adapted to receive communication from the IR transmitters  1004 ,  1006 . 
         [0136]    In exemplary form, the dock cabinet  1050  is mounted to the exterior of a loading dock facility or similar building in a fixed orientation. In other words, the dock cabinet  1050  is adapted to maintain its position with respect to the loading dock facility, regardless of the position of the parked trailers or the position of the stabilizer  900 . In this manner, it is the job of the hustler operator to ensure that the stabilizer is properly aligned so that the transmitters  1004 ,  1006 ,  1056  can send signals and be received by the receivers  1052 ,  1054 ,  1008 . In this manner, the circuitry of the stabilizer is able to communicate with loading dock circuitry and vice versa. It should be noted that each loading dock bay would have its own dock cabinet  1050 . 
         [0137]    The dock cabinet  1050  may also include, or have remotely positioned from the cabinet, a visual display  1058  for the hustler operator. In exemplary form, the visual display includes a plurality of lights that are able to be selectively illuminated. By way of example, the visual display  1058  may include, without limitation, (1) a green pattern of LEDs; (2) a yellow pattern of LEDs; and, (3) a red pattern of LEDs. The pattern may take on any form such as, without limitation, geometric forms including a circle, a square, a triangle, and written text including “caution,” “stop,” and “go.” In exemplary form, the visual display  1058  includes the ability to flash the lights or maintain the illumination. In this exemplary embodiment, the visual display includes three concentric circles  1060  of yellow, green, and red LEDs. As will be discussed in more detail hereafter, the LEDs are selectively illuminated to provide various information to the hustler operator. 
         [0138]    The dock cabinet  1050  is also in communication with an internal cabinet  1066  on the inside of the loading dock facility or similar building. This internal cabinet  1066  includes a visual display  1068  and a lock/unlock switch  1070  to be manipulated by a dock worker inside of the loading dock facility or similar building. In this exemplary embodiment, the visual display  1068  comprises an illuminated tower having a red light and a green light. When the red light is illuminated, dock workers inside the loading dock facility or similar building know what it is not safe to load or unload the parked trailer at the loading dock opening. Conversely, when the light is green, workers know that it is safe to load or unload the parked trailer. It should be noted that each loading dock bay would have its own internal cabinet  1066 . 
         [0139]    An exemplary sequence for using the second exemplary freight trailer stabilizer  900  in conjunction with the operation of the control system and the dock notification and communication system will now be explained. Initially, the parked trailer is spotted at a loading dock facility or similar building so that the rear of the trailer is aligned with and against a loading dock bay. At this time, the landing gear of the trailer are down and the trailer king pin is exposed. 
         [0140]    An exemplary sequence begins by a hustler operator coupling to the stabilizer  900  and coupling an air supply and an electrical supply to the stabilizer and putting the stabilizer in transport mode. It should be noted that in this exemplary sequence, the stabilizer  900  is not under a trailer but is simply sitting out in the yard. Mounting the stabilizer  900  to the hustler includes coupling the fifth wheel of the hustler with the king pin  102  of the stabilizer. After coupling to the king pin  102  of the stabilizer, the hustler operator couples air and electric supplies to the stabilizer  900  using electric and pneumatic adapters (glad-hands). Supplying electricity to the control circuitry and air via the glad-hands is operative to raise the hook  948 , release the wheel brakes  802 , and ensure the repositionable arm  1000  is folded against the frame  106 . Thereafter, the hustler operator is dispatched to position the stabilizer underneath a trailer so it can be unloaded. And the hustler operator visually confirms that he is at the right bay by confirming that the visual display  1058  of the dock cabinet  1050  is displaying a green light. 
         [0141]    In exemplary form, the hustler operator backs the stabilizer  900  underneath the trailer so that the king pin of the trailer is aligned with the tapered cutout  572  and ultimately the king pin enters the king pin cavity  574 . In particular, the stabilizer  900  is adapted to be backed under the trailer in a straight line with the hook pointing toward the rear of the parked trailer. In this orientation, the stabilizer  900  should be longitudinally aligned with the trailer. As the hustler operator back the stabilizer  900  underneath the parked trailer, ultimately, the kingpin of the trailer will reach the stop at the proximal end of the cavity  574 , thereby limiting the distance underneath the trailer that the stabilizer  900  may be positioned. After reaching this point, the hustler operator will realize that the stabilizer cannot be backed any farther underneath the parked trailer and begin to disengage from the stabilizer. At the same time, presuming the king pin remains within the cavity  574 , the king pin sensor  980  sends a signal to the control circuitry  970  that the kingpin is within a predetermined tolerances for disengaging the stabilizer  900  from the hustler. At the same time, the visual display  1058  of the dock cabinet  1050  continues to display a green light, while the visual display  1068  of the internal cabinet  1066  displays a red light. 
         [0142]    The hustler operator then disengages or disconnects the air supply from the hustler to the stabilizer  900 . This action causes a series of events. One such event is that the absence of positive pressure on the hook  948  is operative to lower the hook so that that hook engages the lock box  920 . Unless the hook  948  falls to the bottom of one of the slots  940 , the proximity sensor  990  will not detect that the hook has been correctly deployed. As will be discussed, if the hook  948  is not properly deployed, the hustler operator may have to slightly move the stabilizer forward or rearward to seat the hook within the lock box  920 . At the same time the hook  948  is being repositioned to engage the lock box  920 , the repositionable arm  1000  swings out laterally from the side of the stabilizer  900  to a generally perpendicular position. In this position, the housing  1002  of the arm  1000  should be aligned with the dock cabinet  1050  so that the transmitters  1004 ,  1006 ,  1056  can communicate to the receivers  1008 ,  1052 ,  1054 . The swing arm  1000  is principally repositioned to a deployed position by the damper  1020 . But it should be noted that because the damper  1020  is responsible for repositioning the arm  1000  in the absence of pneumatic pressure, objects contacting the arm may be able to overcome the bias of the damper. But in such a case, presuming the contact is temporary, the arm  1000  will return to the deployment position (extending laterally outward from the stabilizer frame). But during this time, a number of problem conditions may occur. 
         [0143]    The problem conditions that may occur include not properly positioning the stabilizer  900  under the parked trailer. This condition can be remedied simply by the hustler operator repositioning the stabilizer. The hustler operator will know the stabilizer needs to be repositioned because of a number of conditions. First, if the stabilizer  900  is not positioned properly, the transmitters  1004 ,  1006 ,  1056  cannot communicate to the receivers  1008 ,  1052 ,  1054 . At the same time, if the hook  948  is not fully down into one of the slots  940 , the proximity sensor will not send feedback to the control circuitry  970 . Before the operator can deploy the repositionable jack assembly  110 , because the control circuitry will not provide power to the motor  726 , the control circuitry requires two conditions to be satisfied. The first condition is that the hook  948  is properly engaged, which is evidenced by a signal from the proximity sensor  990 . The second condition is that the IR receiver  1008  of the repositionable arm  1000  receives a signal from the IR transmitter  1056  of the dock cabinet  1050  indicating that the stabilizer  900  is properly aligned. Unless both conditions are met, the control circuitry  970  will not power the electric motor to reposition the repositionable jack assembly  110 . But both conditions can be met by having the hustler operator properly align the stabilizer  900  under the parked trailer. 
         [0144]    Presuming the trailer stabilizer  900  is properly positioned so that the transmitters  1004 ,  1006 ,  1056  can communicate to the receivers  1008 ,  1052 ,  1054 , and the hook  948  has properly engaged the lock box  920 , the visual display  1058  of the dock cabinet  1050  illuminates a yellow light or set of lights. In other words, after the stabilizer  900  is properly positioned so the king pin is received, the transmitters and receivers are aligned, and the hook  948  is properly deployed, the visual display  1058  of the dock cabinet  1050  illuminates both a green and a yellow light (because the green light has not been extinguished. In order for this to occur, the control circuitry  970  has received a signal from the tail hook proximity sensor  990  indicative of the tail hook being properly positioned, and then sends a signal via the first IR transmitter  1004  to the first IR receiver  1052  indicating that the tail hook  948  is secure. After these conditions have been met, the control circuitry  970  allows power to go to the motor  726 . 
         [0145]    After the hook  948  engaged and the dock cabinet illuminates the yellow and green lights, the control circuitry  970  allows the hustler operator to deploy (i.e., lower) the repositionable jack assemblies  110 . As discussed previously, the control panel  972  includes a visual display  974  and operator controls  976 . Among the operator controls are separate buttons for raising and lowering the jacks  650 . Accordingly, when the operator wants to lower the jacks  650 , the operator simply presses the down jack button on the control panel  972 . Thereafter, the deployment of the jacks  650  is automated. The control circuitry  970  receives the input from the control panel  972  button to lower the jacks  650  and causes the motor  726  to be turned to lower the jacks  650 . In exemplary form, the jacks  650  comprise screw jacks and the motor is coupled to a transmission  724  shaft having individual clutches  720  that are mounted to the transmission shaft and respective drive shafts  712 . The control circuitry continues to power the motor  726  until both proximity switches  984 ,  986  provide an indication that the jacks are fully down. As mentioned previously, each drive shaft  712  includes a magnet that is detected by a respective proximity switch  984 ,  986  as the shafts rotate to lower the jacks  650 . The control circuitry  970  is programmed to shut off the motor after both proximity switches indicate the further rotation of the drive shafts is not occurring. This may occur, for example, because the magnet is not being sensed by the proximity sensor  984 ,  986  for a predetermined period of time (e.g., 0.5 seconds) or the proximity sensor continues to sense the magnet for more than a predetermined, constant period of time (e.g., 0.5 seconds). Because the surface that the stabilizer is sitting on may be uneven or may have debris underneath one or both jacks, it is not always the case that the jacks will be lowered to the same extent. Accordingly, to accommodate for varying heights of deployment, the clutches allow the transmission shaft to rotate, but not rotate the corresponding drive shaft when the bottom of the jack  650  is touching the ground (including any ground debris, etc.). 
         [0146]    It should be noted that in lieu of the magnetic proximity switches, one may use limit switches mounted to the bottom of each jack  650 . 
         [0147]    After the jacks have been deployed, the visual display  974  of the control panel  972  illuminates a red light. When the red light illuminates on the control panel  972 , a signal is sent via the control circuitry  970  to the second IR transmitter  1006  to transmit a signal indicative of the jacks  650  being deployed. This IR signal is received by the second IR receiver  1054 , which causes the visual display  1058  of the dock cabinet  1050  to change to a red light and extinguish the yellow and green lights. After the hustler driver sees the red light of the dock cabinet  1050 , the operator knows that both the jacks  650  and the hook  948  have been properly deployed and he can disconnect the electric power supply to the stabilizer  900 , disconnect from the stabilizer king pin, and go on to his next task. By disconnecting the power supply to the stabilizer, the control circuitry and all electrical circuitry of the stabilizer is unpowered. In other words, the IR transmitters  1004 ,  1006  are no longer transmitting to the IR receivers  1052 ,  1054  of the dock cabinet  1050 . 
         [0148]    The red light of the visual display  1058  of the dock cabinet  1050  also has an impact on the internal cabinet  1066 . Specifically, prior to the visual display turning on the red light, a loading dock person on the inside of the facility could turn the lock/unlock switch, but the visual display  1068  would remain red. But after the outside dock cabinet  1050  light turns red, the loading dock person on the inside of the facility has the ability to turn the switch to the lock position and the visual display  1068  will illuminate the green light. In other words, until the stabilizer  900  is deployed properly and completely, as documented by the outside dock cabinet  1050 , loading dock personnel cannot change the visual display  1068  on the inside to green, thereby signaling that it was safe to load or unload the parked trailer. It should also be noted that as long as the visual display  1068  displays a green light, the hustler operator will be unable to remove the stabilizer  900 . Simply put, the warehouse personnel control when the stabilizer is removed and must do so by first turning the switch  1070  to the unlock position, thereby changing the visual display  1068  back to a red light and then having the internal cabinet  1066  communicate with the dock cabinet  1050 . While the visual display  1068  on the inside of the warehouse is green, a hustler operator cannot remove the stabilizer  900 . The following is a description of the structure and process that would inhibit removal of the stabilizer  900  while the visual display  1068  of the internal cabinet  1066  is illuminated green (indicative of a safe condition to load or unload the trailer). 
         [0149]    First, presuming one of the warehouse personnel does not turn the switch  1070  to the unlock position on the internal cabinet  1066 , the visual display  1058  of the dock cabinet  1050  will remain a red light. When the visual display of the dock cabinet  1050  is red, the trailer stabilizer  900  cannot be removed. The first indication to the hustler operator is a visual one in that the light of the display  1058  is red instead of green. 
         [0150]    Second, when the display  1058  is red instead of green, the transmitter of the 1056 of the dock cabinet  1050  is dead. Yet the IR transmitter  1056  of the dock cabinet  1050  needs to be operative to send a signal to the IR receiver  1008  so that the control circuitry  970  will provide power to raise the jacks  650  and air to raise the hook  948 . And if the hustler operator has not hooked up the electric connection, the entire system on the stabilizer is dead. More specifically, the control circuitry  970  controls a center return solenoid  1074  that is operative to vent any air pressure imparted to the system when the electrical system of the stabilizer  900  is dead or if the IR transmitter  1056  of the dock cabinet  1050  has not sent a signal to the IR receiver  1008  of the arm  1000 . In other words, when the control circuitry  970  is powered, the circuitry is looking for a signal from the IR transmitter  1056  of the dock cabinet  1050  that it is appropriate to remove the stabilizer  900 . And this signal will never occur when the indicator light is red or if power is not provided to the system. So if the red light of the display  1058  is on, and the hustler operator attempts to remove the stabilizer  900  by hooking up the air supply glad-hand, the air in the stabilizer system will vent. As an additional safety feature, if the hustler operator hooks up the electric power supply and the air supply, and then attempts to raise the jacks  650 , the operation of attempting to raise the jacks by pushing one of the operator controls  976 , the control circuitry shifts the solenoid valve  1074  to vent the air through an on-board air horn  1076  the creates loud horn sound telling the operator and surround people that the operator is erroneously attempting to remove the stabilizer. But presuming the warehouse personnel turns the switch  1070  to the unlock position on the internal cabinet  1066 , the visual display  1058  of the dock cabinet  1050  will discontinue illuminating the red light and now illuminate the green light. 
         [0151]    The green light of the dock cabinet visual display  1058  is the first signal to a hustler operator that it is appropriate to remove the stabilizer  900  because the trailer is ready to leave the warehouse. This also presumes that the IR transmitter  1056  of the dock cabinet  1050  has been operative to send a signal to the IR receiver  1008  so that the control circuitry  970  will allow removal of the stabilizer  900 . 
         [0152]    In order to remove the stabilizer  900 , the hustler operator couples the fifth wheel of the hustler to the king pin  102  of the stabilizer. In addition, the operator couples the electric power connection to the stabilizer  900 . The operator first raises the jacks  650  by pushing the jack up button  977  on the control panel. The control circuitry then sends a signal to the motor  726  to rotate the motor in an opposite direction to raise the jacks  650 . Each of the jacks includes a proximity sensor  984 ,  985  that signals the control circuitry when the jacks are fully raised. This fully raised condition may not be met by turning the drive shafts  712  equally, so the control circuitry waits until both proximity sensor  984 ,  985  signal that each jack is fully raised. After receive signals from both sensors  984 ,  986  that the jacks have been raised, the control circuitry  970  discontinues power to the motor  726  and the green light illuminates on the visual display  974  indicating the jacks are up. Thereafter, the control circuitry  970 , presuming the air lines are coupled to the stabilizer, automatically raises the hook  948  and folds in the arm  100  to lay along side the stabilizer side. At this point, the stabilizer may be removed from underneath the trailer and repositioned under another trailer or stored by discontinuing engagement with the hustler and allowing the stiff leg assembly  108  and the wheels  114  to hold up the stabilizer. At the point in time the stabilizer  900  is disconnected from the hustler, the absence of air pressure results in application of the brakes and dropping of the hook  948 . 
         [0153]    Referencing  FIGS. 45-51 , another exemplary trailer support  101  includes a frame  121  and an axle  141  mounted to the frame  121 . The axle  141  includes one or more wheels  161  mounted proximate the ends of the axle  141 . In this exemplary embodiment, the axle  141  includes tandem wheels  161  mounted at each end, with the tandem wheels including an associated braking assembly  181 . However, it should be noted that the wheels  161  are not required to include a braking assembly  181 . 
         [0154]    Referring specifically to  FIGS. 45-47 , the braking assembly  181  includes a brake pad  201  which applies a force necessary to either a drum or disc  221  to retard rotation of the brake drum and wheel  161  with respect to the axle  141 . A pneumatic brake cylinder  241  is coupled to the brake pads  201  by way of a push rod and cam shaft  251  in order to force the pads  201  against the drum  221  after a predetermined positive pressure is reached within the pneumatic lines  261  feeding the brake chamber. However, the brake cylinder  241  is also operative to force the pads  201  against the drums  221  when insufficient air pressure occurs within the pneumatic lines  261  feeding the cylinder  241 . By way of example, if an air leak occurs within the pneumatic line or a yard truck  2001  (see  FIG. 52 ) is not pneumatically coupled to the trailer support  101 , the brake pads  201  will engage the drums  221  to inhibit rotation of the wheels  161 . In other words, it takes a positive air pressure within the pneumatic brake lines  261  in order to discontinue engagement between the brake pads  201  and the drums  221 . In this exemplary embodiment, the pneumatic lines  261  are in series with a compressed air storage vessel/tank  281  that is mounted to the frame  121 . Thus, the compressed air storage vessel  281  provides an on-frame reservoir of compressed air. As will be discussed in more detail hereafter, the pneumatic lines  261  also includes quick connects  301  (e.g, a glad hand) adapted to be coupled to quick connects  321  of the yard truck  2001  in order for the yard truck to supply compressed air to the braking assembly  181 . 
         [0155]    Referring back to  FIG. 45 , the frame  121  includes a pair of C-shaped cross-section frame rails  341 ,  361  that are equally spaced apart from one another and oriented in parallel toward the rear of the trailer support  101 . Toward the front of the trailer support  101 , the frame rails  341 ,  361  are angled toward one another and eventually converge proximate the front of the trailer support. For the sections of the frame rails  341 ,  361  oriented in parallel, one or more cross-members  381  are joined to the frame rails, such as by welding or bolted fasteners. The cross members  381  may optionally include a block C-shape cross-section. 
         [0156]    The frame  121  also has mounted to it a fifth wheel  401 . Exemplary fifth wheels  401  include class 6, 7, and 8 fifth wheels such as the Fontaine No-Slack 6000 and 7000 Series, available from Fontaine International (www.fifthwheel.com). In this exemplary embodiment, the fifth wheel  401  is mounted in an elevated fashion above the frame rails  341 ,  361  using conventional nut and bolt fasteners. Those skilled in the art will understand that other fifth wheels  401  besides a Fontaine No-Slack may be utilized so long as the fifth wheel inoperative to selectively engage and disengage a king pin of a freight trailer. It should also be noted that the king pin lock/receiver may be pneumatically, electrically, or hydraulically operated, or may simply be manually operated. Those skilled in the art are familiar with the various types of fifth wheels and the various types of locks/receivers that hold the king pin of a freight trailer in place until it is intentionally released. 
         [0157]    Referencing FIGS.  45  and  48 - 50 , the trailer support  101  may also include a pair of repositionable wheel chocks  501  that operate to retard rolling motion of the wheels  161  when deployed. In exemplary form, each wheel chock  501  is mounted to a repositioning device  521  that utilizes fluid power (pneumatic, hydraulic, etc.) to switch between deployment and storage of the wheel chocks  501 . It should also be noted that the wheel chocks  501  may alternatively be deployed using a manual crank (not shown) that is mounted to the through rod  641 . In either circumstance, when the wheel chocks  501  are deployed, the chocks are wedged between the wheels  161  and the ground. Consequently, as the wheels  16  attempt to rotate forward, the deployed chocks  501  provide a resistive force sufficient to retard forward rotation of the wheels. Conversely, when the chocks  501  are stored, the wheels  161  are able to rotate (forward or rearward), presuming some other device is not operative to retard rotational motion such as the braking assembly  181 . 
         [0158]    Referring to  FIGS. 45 and 48 , the repositioning device  521  includes a pneumatic cylinder  541 , which is supplied with air from pneumatic supply lines  551 . One end of the pneumatic cylinder  541  is mounted to the underside of the cross-member  381 . The opposite end of the pneumatic cylinder  541  includes an actuating piston  561  with a clevis  581  mounted to the far end of the piston. The clevis  581  is pivotally mounted to an L-shaped bracket  601  by way of a pin  621  that extends through both the clevis and bracket. A through rod  641 , having a circular cross-section, is received within a cylindrical cavity formed by a cylindrical housing  681  mounted to the opposite end of the L-shaped bracket  601 . A through hole extending into the cylindrical cavity is threaded to receive a fastener, such as a bolt  661 , that extends into contact with an exterior of the through rod  641  to secure the cylindrical housing  681  to the through rod  641 . Accordingly, rotational motion of the cylindrical housing  681 , when the bolt  661  is tightened within the through hole, is transferred to the through rod  641 , thereby causing the through rod to correspondingly rotate when the cylindrical housing is rotated. The rotational motion of the through rod  641  is transferred to the chocks  501  and is operative to reposition the chocks  501  between deployment and storage positions. 
         [0159]    In this exemplary embodiment, the through rod  641  is located beneath and mounted to a cross-member  381  of the frame  121  using several brackets  701  with circular bushings  721 . The bushings  721  operate to allow the through rod  641  to axially rotate with respect to the brackets  701 , while retaining the horizontal and vertical position of the through rod. In exemplary form, a single through rod  641  is utilized to extend across the entire width of the frame  121  and outward beyond the frame in front of the wheels  161 . 
         [0160]    Referencing  FIGS. 45 ,  49  and  50 , each repositionable wheel chock  501  includes a telescopic pole  801  mounted to the through rod  641  that extends laterally beyond the frame  121 . In exemplary form, the telescopic pole  801  comprises a first hollow tube  821  and a second, larger hollow tube  841 , where the first tube has an exterior that is small enough to be received within the interior of the second tube. Because of the size differential between the tubes  821 ,  841 , the tubes are operative to slide against one another to increase or decrease the length of the pole  801  as necessary. In this regard, the second tube  841  has a closed opposite end that optionally houses a spring (not shown), which is operative to bias the first hollow tube  821  with respect to the second tube. However, it should be noted that the tubes need not be telescopic or operative to slide with respect to one another in order to deploy the wheel chock  501 . For example, tubes  821 ,  841  may be replaced by a single tube or multiple tubes that are rigidly mounted to one another to avoid longitudinal length changes. 
         [0161]    Opposite the closed end of the second tube  841 , the first tube  821  includes a transverse hollow cylinder  861 . A cavity on the interior of the cylinder  861  allows for throughput of the through rod  641 . Additionally, the through rod  641  includes a longitudinal keyway  871  formed on its exterior that is aligned with a longitudinal keyway  891  formed on the interior of the cylinder  861 . In this fashion, after the keyways  871 ,  891  have been aligned (i.e., overlap) with one another, a key  911  is inserted into both keyways  871 ,  891  so that rotation of the through rod  641  results in corresponding rotation of the cylinder  861 . In this exemplary embodiment, the keyways  871 ,  891  exhibit a rectangular, axial cross-section that accommodates the key  911 , which also exhibits a rectangular, axial cross-section. A hole (not shown), which extends through the cylinder  861  and into the keyway  891 , is adapted to receive a threaded fastener  881 . By inserting the threaded fastener  881  into the hole, where the hole overlaps the keyway  891 , the threaded fastener is operative to contact the key  911  and lock the key within the keyways  871 ,  891 . 
         [0162]    Opposite the closed end of the second tube  841 , an arm  901  is mounted to the lateral exterior of the second tube. The arm  901  extends away from the closed end of the second tube  841  and extends beyond the open end of the second tube  841  in parallel with the first tube  821 . In this exemplary embodiment, the arm  901  by way of a through bolt is mounted to a spring  921 , where the spring is coupled to a cable  941 , which is itself mounted to a chock block  961 . As will be discussed in more detail below, the spring  921  provides a tension force that retains the chock block  961  in a predetermined position, thereby retarding the chock block  961  from digging into the ground as the repositionable wheel chock  501  is moved from its storage position to its deployment position. In order to maintain the proper tension on the chock block  961 , a guide pulley  981  is mounted to the second tube  841 , where the guide pulley  981  receives the cable  941 . 
         [0163]    Proximate the closed end of the second tube  841 , a bracket  1001  is mounted to the second tube. This bracket  1001 , in exemplary form, includes a block C-shaped segment  1021  that is spaced apart from the second tube by way of an extension  1041 . The block C-shaped segment  1021  includes extension plates  1031  pivotally mounted by way of a pivot pin  1051  to allow articulation of the chock block  961  and provide an allowance for coaxial discrepancy between the through rod  641  and the stabilizer&#39;s wheels  161 . A guide arm  1061  is mounted to the rear exterior of the C-shaped segment  1021 . In this exemplary embodiment, the guide arm  1061  includes a through hole that receives a fastener to pivotally mount a roller assembly  1081  to the guide arm. 
         [0164]    The roller assembly  1081  includes a first roller  1101  mounted opposite a second roller  1121 , where both rollers are mounted to opposing rails  1141  that are tied together by a cross-brace  1161 . The first roller  1101  is rotationally repositionable with respect to the rails  1141  and is adapted to contact the ground when the wheel chock  501  is deployed in its barrier or deployment position. Similarly, the second roller  1121  is rotationally repositionable with respect to the rails  1141  and is adapted to contact the rear of the chock block  961  and overcome the bias of the spring  921  to rotate the chock block when the first roller  1101  reaches the ground. 
         [0165]    The chock block  961  is accommodated within the C-shaped segment  1021 . The chock block  961  is pivotally mounted to the extension plates  1031  by way of a pivot shaft  1181  that concurrently extends through the chock block and the extension plates. A rear portion of the chock block  961  includes a connector  1201  that couples the chock block to the cable  941 . 
         [0166]    Referring to  FIGS. 45 and 51 , the trailer support  101  may also includes a winch  1301  mounted to a rear cross member  381 . The winch  1301  may be pneumatically, hydraulically, or electrically driven using a power connection line  1321  that includes a quick connect  1341  in order to receive power from a power source, such as from a yard truck  2001  (see  FIG. 52 ). Alternatively, the winch  1301  could be manually actuated using a hand crank (not shown). In this exemplary embodiment, the winch  1301  includes a motor and a cable  1361  mounted to a rotating spool. A free end of the cable  1361  includes a hook  1381  that is adapted to interface with a ground cleat  1501  (see  FIG. 53 ) in order to pull the rear of the trailer support  101  toward the ground cleat. For use with the instant embodiment, exemplary electric winches  1301  include, without limitation, the RN30W Rufnek worm gear winch available from Tulsa Winch (www.team-twg.com). 
         [0167]    Referencing  FIGS. 45 and 54 , the trailer support  101  may further include a signaling system  1601 . This signaling system  1601  provides a visual display  1621  that alerts personnel within a warehouse or loading dock facility  1641  when the trailer  2201  is stabilized using the trailer support  101 . In exemplary form, the visual display  1621  is mounted on the interior of the warehouse or loading dock facility  1641  proximate the loading dock. As will be appreciated by those skilled in the art, when the rear of the trailer  2201  is backed up adjacent and aligned with respect to the loading dock opening, personnel within the warehouse or loading dock facility  1641  often cannot see through the loading dock opening because the rear of the trailer  2201  is occupying the entire loading dock opening. Therefore, the visual display  1601  takes the place of a manual visual inspection and indicates whether the trailer  2201  is stabilized or not to accommodate for the absence of a direct line of sight. In order for the visual display  1601  to know when to display an indicia that it is safe to load/unload the trailer  2201 , the trailer stabilizer  101  includes an on-board infrared light source  1661 . 
         [0168]    In this exemplary embodiment, the infrared light source  1661  is powered by an electrical source associated with the yard truck  2001  (see  FIG. 52 ). However, it should be noted that the infrared light source could also be powered by an on-board power source (such as a battery or generator) associated with the trailer stabilizer  101 . The infrared light source  1661  is selectively powered, however, only after the trailer support  101  has been secured. The infrared light source  1661 , when powered, is operative to generate infrared light that is detected by an infrared detector  1681  located on the exterior of the warehouse or loading dock facility  1641 . When infrared light is detected by the detector  1681 , the detector communicates this detection to the visual display  1621  so that personnel within the warehouse or loading dock facility  1641  know it is safe to load or unload the trailer  2201 . However, the visual display  1601  may provide more than a simple visual indication that the trailer stabilizer is secured. 
         [0169]    The signaling system  1601  also includes a king pin sensor  1701  and a wheel chock sensor  1721 . The king pin sensor  1701  is operative to determine whether or not a trailer king pin  2221  (see  FIG. 52 ) is secured to the fifth wheel  401 . When the king pin  2221  is secured to the fifth wheel  401 , the sensor  1701  senses the position of the king pin within the opening of the fifth wheel. The sensor  1701  may also include an ancillary sensor (not shown) that confirms the king pin  2221  is locked within the fifth wheel  401 . Likewise, the wheel chock sensor  1721  is operative to detect the position of the wheel chocks  501 , such as when the wheel chocks are deployed on the ground in a blocking position directly in front of the wheels  161 . Both the king pin sensor  1701  and the wheel chock sensor  1721  are in communication with a controller  1741  that uses a wireless transmitter to communicate information concerning the position of the king pin  2221  and the position of the wheel chocks  501  to the visual display  1601 , which itself includes a wireless receiver. 
         [0170]    Referring to  FIGS. 52 and 53 , a yard truck  2001  includes a cab  2021 , a chassis  2041 , an engine  2061 , electrical connections  2081 , pneumatic connections  2101 , and a repositionable fifth wheel  2121 . In addition, the yard truck  2001  includes a tow hook  2141  that receives the tow eye  2161  of the trailer support  101  in order to couple the yard truck  2001  to the trailer support  101 . 
         [0171]    In practice, the yard truck  2001  attaches itself to the trailer support  101  by way of the yard truck&#39;s tow hook  2141  being coupled to the tow eye  2161  of the trailer support  101 . In addition to attaching the yard truck  2001  to the trailer support  101  using the hook  2141  and eye  2161 , the yard truck operator also connects quick connects  1341 ,  301  of the trailer stabilizer  101  to quick connects  2171 ,  2181  associated with the yard truck to supply electrical and pneumatic power. It should also be noted that the yard truck  2001  may include hydraulic pump(s), lines, and connections (not shown) that connect to connections, lines, and devices of the trailer support  101 , such as when the winch  1301  and/or repositioning device  521  is hydraulically driven. After completing connections between the yard truck  2001  and the trailer support  101 , the yard truck operator then drives the yard truck into position with respect to a trailer  2201  having already been parked at a loading dock so that the doors of the trailer are open and the associated opening at the rear of the trailer is adjacent a loading dock opening. 
         [0172]    At such a point in time, the trailer  2201  is initially supported by its landing gear (not shown). But, as discussed previously, the landing gear is not made to accommodate the high forces associated with a forklift repetitively entering and exiting the trailer to load or unload goods. As is evident to those skilled in the art, when loading a trailer, the initial weight of the loaded goods is positioned at the front of the trailer and is disproportionally born by the landing gear. Similarly, when a trailer is unloaded, the last weight to be taken off the trailer comes from the goods located at the front of the trailer, where this weight is disproportionally born by the landing gear. In order to ensure that the trailer does not nosedive in case of landing gear failure, or that the trailer tips over on either lateral side, the instant disclosure provides a stabilizing device to retard nose dive or lateral tip over. 
         [0173]    Referring again to  FIGS. 52 and 53 , after the yard truck  2001  has attached itself to the trailer stabilizer  101  and located a trailer that has yet to be stabilized, the yard truck thereafter backs the trailer stabilizer  101  underneath the trailer  2201 . When backing the trailer stabilizer  101 , the rear of the stabilizer (where the winch  1301  is located) moves underneath the trailer first and is aligned so that the fifth wheel  401  receives the trailer king pin  2221 . While the trailer stabilizer  101  is being backed underneath the trailer  2201  and before the king pin  2221  is secured within the fifth wheel  401 , the repositionable wheel chocks  501  are in a storage position and the brake assemblies  181  are free (i.e., not locked). It should also be noted that while the yard truck  2001  is backing the stabilizer  101  underneath the trailer  2201 , the winch  1301  is preferably retracted. Continued backing of the yard truck  2001  causes the trailer stabilizer  101  to be further repositioned underneath the trailer  2201 , eventually so much so that the king pin  2221  engages the fifth wheel  401  and becomes locked within the fifth wheel, thereby coupling the trailer stabilizer to the trailer. At this time, the king pin sensor  1701  detects the position of the king pin  2221  with respect to the fifth wheel  401  and communicates a signal indicative of the king pin position to the controller  1741  (see  FIG. 45 ). Thereafter, the controller  1741  wirelessly communicates a signal to the visual display  1681  (see  FIG. 54 ), which in turn displays visual indicia representing to dock workers that the king pin  2221  is secured to the trailer stabilizer  101 . 
         [0174]    After the trailer stabilizer  101  is coupled to the trailer  2201 , a number of events occur to lock the position of the trailer stabilizer with respect to the trailer. One of these events may include the yard truck operator locking the braking assembly  181  of the trailer stabilizer by depressurizing the pneumatic lines  261  (see  FIG. 45 ). This depressurization causes the brake pads  201  (see  FIG. 46 ) to be forced against the brake drum/disc  221 , thereby retarding rotational motion of the wheels  161 . Another possible event is the deployment of the repositionable wheel chocks  501  using the repositioning device  521 . 
         [0175]    The yard truck operator controls, using standard internal controls within the yard truck  2001  to control the air pressure though line  2101 , the pneumatic pressure applied to the pneumatic cylinder  541  to extend or retract the piston  561 , thereby rotating the through rod  641  in either a clockwise or a counterclockwise direction. As discussed previously, rotation of the through rod  641  is operative to reposition the wheel chocks  501  between the storage position and the blocking position. In this manner, the yard truck operator is able to lower or raise the wheel chocks  501  without ever leaving the cab of the yard truck  2001 . When the wheel chocks  501  are deployed so that the chocks are in front and adjacent at least one of the wheels  161 , the wheel chock sensor  1721  senses this position and communicates a signal to the controller  1741  (see  FIG. 45 ). Thereafter, the controller  1741  wirelessly communicates a signal to the visual display  1681  (see  FIG. 54 ), which in turn displays visual indicia representing to dock workers that one or all of the wheel chocks  501  is deployed in a blocking position with respect to the wheels  161  of the trailer stabilizer  101 . But the yard truck operator may need to exit the cab to couple the cable  1361  and hook  1381  to the ground, as well as to disconnect pneumatic and electrical connections extending from the yard truck  2001  to the trailer stabilizer  101 . 
         [0176]    In exemplary form, after the brake assembly  181  has been locked and the wheel chocks  501  have been deployed, the yard truck operator may exit the cab to secure the trailer support  101  to the ground using the winch  1301 . The winch may be powered from an electrical power source on board the trailer stabilizer  101  or on board the yard truck  2001 . In either circumstance, the winch  1301  is unwound a predetermined amount so that there is enough cable  1361  for the hook  1381  to reach the ground cleat  1501 . The hook  1381  is thereafter mounted to the cleat  1501 , and the winch  1301  is driven to wind the cable  1361  in order to remove the slack from the line. The winch  1301  associated controls (not shown) that are operative to discontinue winding of the cable  1361  after the cable reaches a predetermined tension. When taught, the cable  1361  and winch  1301  are operative to pull the trailer stabilizer  101  toward the rear of the trailer  2201 , which acts to pull the fifth wheel  401  toward the rear of the trailer. Because the fifth wheel  401  at this point has received the king pin  2221 , the fifth wheel  401  pushes against the front of the king pin to effectively wedge the trailer  2201  between the loading dock (not shown) and the fifth wheel  401  and wedge the king pin between the fifth wheel  401  and the ground cleat  1501 . 
         [0177]    As soon as the winching operation is complete, a switch  1691  associated with the infrared light source  1661  is tripped, thereby powering the light source and generating infrared light. The placement of the infrared light source  1661  is at the rear of the trailer support  101  and is designed to provide a direct line of sight between the light source and the light detector  1681  (see  FIG. 54 ) mounted to the warehouse or loading dock facility  1641 . It should be noted that the light source may be powered by the yard truck  2001  or may be powered by an on-board energy source (not shown) such as a generator or a battery. In exemplary form, the light source includes a timing circuit that only allows the infrared light source to be powered for a predetermined time. Regardless of the power source used, the light source  1661  is operative to generate infrared light that will be detected by the detector  1681 . 
         [0178]    The detector  1681 , which is mounted to the warehouse or loading dock facility  1641 , is operative to detect infrared light generated by the light source  1661 . When infrared light is detected by the detector  1681 , a signal is sent to the visual display  1621  indicating that the trailer stabilizer  101  is in a secured position with respect to the trailer  2201 . In exemplary form, the visual display  1621  includes a red and green light. When illuminated, the red light indicates that the trailer  2201  parked at the loading dock is not ready to be loaded or unloaded because the trailer support  101  has not yet been secured to the trailer. In contrast, when illuminated, the green light indicates that the trailer  2201  parked at the loading dock is ready to be loaded or unloaded because the trailer support  101  is secured to the trailer. 
         [0179]    When a trailer  2201  is fully loaded or unloaded, the yard truck  2001  reattaches itself to the trailer support  101 , which includes reattaching the quick connects  301 ,  1341 . Thereafter, to the extent the support  101  is coupled to the ground cleat  1501 , the winch  1301  is unwound and the hook  1381  is disengaged from the cleat, followed by winding of the cable  1361 . As soon as the winch cable  1361  is unwound, thereby allowing decoupling of the hook  1381  from the cleat  1501 , the infrared light source  1661  is powered and generates infrared light. This light is in turn detected by the detector  1681 , which is operative to send a signal to the visual display  1621  indicating that the trailer support  101  is not longer secured to the trailer  2201 . As discussed previously, a red light is illuminated on the display  1621  indicating to dock personnel that it is not safe to load or unload goods from the trailer. It should be noted that in case the visual display  1621  gets out of sequence, it may be manually reset to display the red light or some other indicia reflecting that the trailer  2201  is not mounted to the trailer support  101 . 
         [0180]    Presuming the winch  1301  has been disengaged from the cleat  1501  or not even used, the yard truck operator the supplies power to the repositioning device  521  in order to retract the repositionable wheel chocks  501 . Presuming the wheel chocks  501  were not used or have already been retracted, the yard truck operator supplies power to the brake assemblies  181  in order to free the brakes and allow the wheels to turn with respect to the frame  121 . At this point, the king pin  2221  is released from the fifth wheel  401  and the trailer support may be removed from under the trailer  2201 . At the point in time where the trailer stabilizer  101  is removed from under the front of the trailer  2201 , it is up to the landing gear to support the frontal load of the trailer. 
         [0181]    Referring to  FIGS. 55 and 56 , a second exemplary trailer support  3101  includes a frame  3121  and an axle  3141  mounted to the frame  3121 . The axle  3141  includes one or more wheels  3161  mounted proximate the ends of the axle  3141 . In this exemplary embodiment, the axle  3141  includes tandem wheels  3161  mounted at each end, with the tandem wheels including an associated braking assembly (not shown), which is identical to that of the first exemplary embodiment  101  (see  FIGS. 45-47 ). The braking assembly includes brake pads, brake drum/discs, and a pneumatic brake cylinder to apply a brake force to the trailer support  3101  when insufficient air pressure occurs within the pneumatic line feeding the cylinder. For purposes of brevity, reference is had to  FIGS. 46 and 47  and the corresponding written description for a braking assembly that may be used as the instant braking assembly  3101 . 
         [0182]    The frame  3121  includes a pair of C-shaped cross-section frame rails  3341  that are equally spaced apart from one another and oriented in parallel toward the rear of the trailer support  3101 . Toward the front of the trailer support  3101 , the frame rails  3341  are angled toward one another and eventually converge at a hitch  3361  proximate the front of the trailer support. When oriented in parallel, the frame rails  3341  are jointed together by mounting one or more cross-members (not shown) to the frame rails (via welding, nuts and bolts, etc.), where the cross-members may optionally include a block C-shape cross-section. 
         [0183]    At least one of the cross-members of the frame  3121  has mounted to it a fifth wheel  3401  in an elevated fashion above the frame rails  3341  (using conventional nut and bolt fasteners and/or welds). Again, the fifth wheel  3401  is analogous to the fifth wheel  401  discussed with respect to the first exemplary embodiment  101 . 
         [0184]    The trailer support  3101  also includes an actuatable draw bar and associated hook  3801  that is pivotally mounted to the frame  3121  between an elevated position and an engaged position (compare  FIGS. 55 and 56 ). When in the draw bar and associated hook  3801  is in the engaged position (see  FIG. 56 ), the hook is at or approximate ground level to engage a cleat  4201  mounted to the ground. When the draw bar and associated hook  3801  engage the cleat, appreciable forward movement of trailer support  3101  away from the cleat  4201  is not possible. Conversely, when the draw bar and associated hook  3801  is in the disengaged position (see  FIG. 55 ), the hook is above ground level and inoperative to engage the cleat  4201 . Thus, when the draw bar and associated hook  3801  are disengaged from the cleat  4201 , appreciable forward movement of trailer support  3101  may be possible, presuming wheel chocks are not deployed in a barrier position. 
         [0185]    Referring to  FIGS. 55-58 , in this exemplary embodiment, the draw bar and associated hook  3801  comprises quarter inch steel rectangular tubing  3821  extending longitudinally and having opposing ends  3841 ,  3861 . At one end  3841 , a cylindrical coupling  3881  is fastened to the tubing, such as by welding, and oriented so that a through opening  4001  is generally perpendicular to the longitudinal length of the tubing  3821 . This opening  4001  receives an axle  4021  that is mounted to the trailer support  3101  so that the coupling  3881  pivots around the axle  4021 . In exemplary form, the axle  4021  is sized to concurrently extend through the opening  4001  and corresponding openings that are aligned through spaced apart brackets  4041  mounted to the trailer support  3101  so that the longitudinal ends of the axle extend through the brackets. Each end of the axle  4021  includes a radial through hole that is sized to receive a respective cotter pin (not shown) and thereby inhibit the axle from being displaced laterally (i.e., from side to side). One or both of the cotter pins may be removed to allow the axle  4021  to be laterally repositioned with respect to the brackets  4041  and the cylindrical coupling  3881 . When the draw bar and associated hook  3801  is mounted to the trailer support  3101 , the cylindrical coupling  3881  interposes the brackets  4041  so that the through opening  4001  is longitudinally aligned with the corresponding openings of the brackets. At the same time, the axle  4021  is inserted through the openings in the coupling  3881  and brackets  4041  so that the ends of the axle extend just beyond the bracket openings. Thereafter, the cotter pins are installed, and the draw bar and associated hook  3801  is pivotally mounted to the trailer support  3101 . 
         [0186]    A heavy duty hook  4061  is mounted to the end  3861  of the rectangular tubing  3821  opposite the cylindrical coupling  3881 . This heavy duty hook  4061  is fabricated from high strength steel and includes a linear segment  4081  that extends substantially coaxial with the tubing  3821 . The far end of the segment  4081  is rounded over 4101. The hook  4061  defines a cavity  4121  on its interior that is adapted to retain at least one of a plurality of dowel pins  4501  associated with the cleat  4201  when the draw bar and associated hook  3801  is in the engaged position. 
         [0187]    Referring to  FIGS. 59-61 , the exemplary cleat  4201  comprises an open top with a longitudinal block U-shaped tunnel  4221  having opposed vertical sidewalls  4241 ,  4261  and a bottom wall  4281 . Trapezoidal plates  4301 ,  4321 ,  4341 ,  4361  are mounted to tapered ends and to the top of the vertical sidewalls  4241 ,  4261 . In addition, the trapezoidal plates  4301 ,  4321 ,  4341 ,  4361  are mounted to each other at their angled ends. In this manner, the trapezoidal plates  4301 ,  4321 ,  4341 ,  4361  operate to provide an angled incline so that unintended objects contacting the cleat  4201  can pass thereover. 
         [0188]    On the interior of the cleat  4201  are a series of spaced apart dowel pins  4501  that span laterally across the vertical sidewalls  4241 ,  4261 . Each dowel pin  4501  includes a flange  4521  that extends perpendicularly from the circumference and extends substantially the entire distance between the vertical sidewalls  4221 ,  4261  of the tunnel  4221 . The vertical sidewalls  4221 ,  4261 ,  4221  include corresponding openings in order to receive the dowel pins  4501 . But it should be noted that in this exemplary cleat  4201 , the dowel pins  4501  are not rotationally repositionable with respect to the vertical sidewalls  4221 ,  4261 . However, it is within the scope of the disclosure to provide dowel pins  4501  and flanges  4521  that are rotationally repositionable. Specifically, the flanges  4521  may be spring biased and operative to close the gap between adjacent pins  4501  in order to prohibit unintended objects from entering the interior of the cleat  4201 . 
         [0189]    In exemplary form, the forward most dowel pin  4501  is mounted to the vertical sidewalls  4241 ,  4261  so that its flange  4521  extends to meet the top edge of the forward trapezoidal plate  4301 . As will be discussed in more detail below, this orientation ensures that the hook  4061  does not inadvertently snag the top edge of the forward trapezoidal plate  4301 . The remaining dowel pins  4501  are oriented so that the flanges  4521  are upwardly sloped from front to back. 
         [0190]    The orientation for the flanges  4521  of the second and successive dowel pins  4501  provides a series of ramps that allow the hook  4061  to move from front to back across the dowel pins without becoming snagged. Simply put, the hook  4061 , when moving from front to back, slides up the flange and over one of the dowel pins, to only drop down and contact a successive flange of a successive dowel pin. The same process may be repeated until the hook reaches the top of last dowel pin or the hook is moved forward. At this point, the hook  4061  slides over the last dowel pin and begins to slide down the face of the rear trapezoidal plate  4341 . In contrast, when the hook  4061  is repositioned from rear to front, the cavity  4121  of the hook receives whichever dowel pin  4501  is nearest in order to retain the hook within the cleat  4201 . This retention occurs because the angled surfaces provided by the flanges  4521  operate to direct the hook  4061  into contact with the nearest dowel pin  4501  so that the dowel pin is received within the cavity. In this received position, the draw bar and associated hook  3801  cannot be moved forward to the next nearest dowel pin, nor can the hook  4061  be vertically repositioned out of engagement with the dowel pin. In order to discontinue engagement of the hook  4061  with the instant dowel pin  4501 , the draw bar and associated hook  3801  is repositioned rearward (from front to back) until the tip of the hook  4061  clears the instant dowel pin. Thereafter, the draw bar and associated hook  3801  may be vertically raised to remove the hook  4061  from within the cleat  4201 . 
         [0191]    Referring back to  FIGS. 55 and 56 , in order to vertically reposition the draw bar and associated hook  3801 , a pneumatic cylinder  4601  is concurrently coupled to the rectangular tubing  3821  and corresponding brackets  4621  mounted at the rear of the frame  3121 . In this exemplary embodiment, air supply lines (not shown) are coupled to the pneumatic cylinder  4601  and are adapted to receive air from a yard truck or other tractor (see e.g.,  FIGS. 52 and 53 ). The pneumatic cylinder  4601  is pivotally mounted to the rear of the frame  3121  by way of the corresponding brackets  4621 , while the pneumatic cylinder piston  4661  is repositionably mounted to a clevis  4681  on the rectangular tubing  3821  using a through pin (not shown). The clevis  4681  is formed by two parallel metal plates that are welded to the rectangular tubing, where each plate has an aligned hole that receives the through pin. In this manner, when the piston  4661  is extended from the cylinder  4601 , the draw bar and associated hook  3801  are pivoted about the axle  4021  in order to lower the hook  4061 . Conversely, when the piston  4661  is retracted into the cylinder  4601 , the draw bar and associated hook  3801  are pivoted about the axle  4021  in order to raise the hook  4061 . 
         [0192]    In addition, the exemplary trailer support  3101  may include a pair of repositionable wheel chocks  4801  having generally the same structure and mode of operation as the wheel chocks  501  discussed with respect to the foregoing embodiment. Accordingly, for purposes of brevity, a detailed discussion of the components and mode of operation has been omitted. 
         [0193]    In operation, a yard truck (not shown) attaches itself to the trailer support  3101  by way of the yard truck&#39;s tow hook being coupled to the hitch  3361  of the trailer support. In addition to attaching the yard truck to the trailer support  3101  using the hitch  3361 , the yard truck operator also connects quick connects of the trailer stabilizer  3101  to quick connects associated with the yard truck to supply electrical and pneumatic power to the trailer stabilizer. It should also be noted that the yard truck may include hydraulic pump(s), lines, and connections (not shown) that connect to connections, lines, and devices of the trailer support  3101 , such as when the draw bar and associated hook  3801  is hydraulically repositioned by way of a hydraulic cylinder instead of a pneumatic cylinder  4601 . 
         [0194]    After completing connections between the yard truck and the trailer support  3101 , the yard truck operator then drives the yard truck into position with respect to a trailer having already been parked at a loading dock so that the doors of the trailer are open and the associated opening at the rear of the trailer is adjacent a loading dock opening. The yard truck operator then begins to back the trailer stabilizer  3101  underneath the trailer, with the rear of the stabilizer where the draw bar and associated hook  3801  is located moving underneath the trailer first so that the fifth wheel  3401  is aligned with the king pin of the trailer. While the trailer stabilizer  3101  is backed underneath the trailer, the repositionable wheel chocks  4801  are in a storage position, the brake assemblies of the trailer stabilizer are free (i.e., not locked), and the draw bar and associated hook  3801  are in a raised position. Continued backing of the yard truck causes the trailer stabilizer  3101  to be further repositioned underneath the trailer, eventually so much so that the king pin engages the fifth wheel  3401  and becomes locked within the fifth wheel, thereby coupling the trailer stabilizer to the trailer. At this time, a king pin sensor detects the position of the king pin with respect to the fifth wheel  3401  and communicates a signal indicative of the king pin position to a controller associated with the yard truck. Thereafter, the controller wirelessly communicates a signal to a visual display (not shown), which displays visual indicia within a warehouse to dock workers telling them that the king pin is secured to the trailer stabilizer  3101 . 
         [0195]    After the trailer stabilizer  3101  is coupled to the trailer, a number of events occur to lock the position of the trailer stabilizer with respect to the trailer. First, the yard truck operator lowers the draw bar and associated hook  3801  so that the hook  4061  contacts the top of the cleat  4201 , which is already securely mounted to the pavement/concrete underneath the trailer, in order for the hook to float on top of the cleat. The yard truck operator then pulls slightly forward so that the hook  4061  captures one of the dowel pins  4501  within the cavity  4221  and retards further forward movement of the stabilizer  3101 . A sensor associated with the stabilizer  3101  detects the deployed position of the draw bar and associated hook  3801  and communicates this to the controller. The controller then wirelessly communicates a signal to a visual display (not shown) or powers an infrared light source to communicate with an infrared light detector operatively coupled to the visual display letting dock workers know that the draw bar and associated hook  3801  is deployed. 
         [0196]    In addition to securing the hook  4061  to the cleat  4201 , the yard truck operator also locks the braking assembly of the trailer stabilizer by depressurizing the pneumatic lines feeding the drum assemblies. This depressurization causes the brake pads to be forced against the brake drum/disc, thereby retarding rotational motion of the wheels  3161 . Another event is the deployment of the repositionable wheel chocks  4801  using a pneumatic cylinder  4821 . Deployment of the wheel chocks  4801  is essentially the same as that discussed for the first exemplary embodiment and has been omitted only to further brevity. Thereafter, the yard truck unhooks any pneumatic and electrical connections with the trailer stabilizer and continues on to the next spotted trailer. 
         [0197]    After the trailer is fully loaded or unloaded, the yard truck reattaches itself to the trailer support  3101 , which includes reattaching any pneumatic and electrical connections. After these connections have been reestablished, the repositionable wheel chocks  4801  are raised to a storage position and the brake assemblies are freed (i.e., not locked). This allows the yard truck operator to slightly reposition the trailer support  3101  toward the rear of the trailer to unseat the hook  4061  from the nearest dowel pin  4501  of the cleat  4201 . After the hook  4061  is unseated, the yard truck operator manipulates valves to supply air to the air supply lines coupled to the pneumatic cylinder  4601 . This, in turn, causes the piston  466  to retract within the cylinder  4601 , thereby pivoting the draw bar and associated hook  3801  about the axle  4021 , thus raising the hook  4061 . After the hook  4061  has been raised to no longer potentially come in contact with the cleat  4201 , and the landing gear of the trailer has been lowered, the yard truck pulls the trailer support  3101  out from under the trailer so that the king pin of the trailer no longer engages the fifth wheel  3401 . 
         [0198]    The exemplary trailer stabilizer  3101  is operative to inhibit trailer nosedives, tip-overs, and trailer creep. Moreover, the exemplary trailer stabilizer  3101  includes a means for informing dock personnel when the trailer stabilizer  3101  is mounted to the trailer, thereby informing the dock personnel that it is safe or unsafe to load/unload the trailer, similar to that discussed for the first exemplary embodiment. 
         [0199]    Following from the above description and invention summaries, it should be apparent to those of ordinary skill in the art that, while the methods and apparatuses herein described constitute exemplary embodiments of the present invention, the invention contained herein is not limited to this precise embodiment and that changes may be made to such embodiments without departing from the scope of the invention as defined by the claims. Additionally, it is to be understood that the invention is defined by the claims and it is not intended that any limitations or elements describing the exemplary embodiments set forth herein are to be incorporated into the interpretation of any claim element unless such limitation or element is explicitly stated. Likewise, it is to be understood that it is not necessary to meet any or all of the identified advantages or objects of the invention disclosed herein in order to fall within the scope of any claims, since the invention is defined by the claims and since inherent and/or unforeseen advantages of the present invention may exist even though they may not have been explicitly discussed herein.