Patent Publication Number: US-8534694-B2

Title: Powered converter dolly and securing device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Patent Application No. 61/247,397, filed Sep. 30, 2009, and U.S. Provisional Patent Application No. 61/264,392, filed Nov. 25, 2009, which are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present disclosed technology relates generally to trailer transportation and securing devices, and in particular a converter dolly that is self-powered for movement around a trailer yard and for movement into contact with a lead-trailer and a load-trailer, and a trolley that rolls within a channel in the middle of a railroad flatcar capable of securing a load thereto. 
     2. Description of the Related Art 
     A converter dolly is used to attach a load-trailer to a lead-trailer or tractor-trailer assembly thereby enabling a tractor-trailer assembly to pull two or more trailers. Converter dollies generally consist of a frame having one or two axles, a coupling member for attachment to a lead-trailer, and a fifth wheel plate attached to the top of the frame above the axles for engaging the kingpin of a load-trailer. The conventional method of assembling dollies and load-trailers requires one or more people to manually maneuver an uncoupled dolly around a trailer yard and into contact with an uncoupled trailer. After the load-trailer dolly assembly is created, a tractor-trailer assembly is backed up to it for joining of the two assemblies. This procedure is repeated for each load-trailer dolly assembly that is attached to a lead trailer. 
     The conventional method of assembling trailers and dollies creates dangerous conditions for people maneuvering the dollies and attaching them to a tractor-trailer, and for personnel around backward moving tractor-trailer assemblies. A great deal of manual effort is required of an operator to lift the front end of the dolly off the ground and keep the dolly under control when maneuvering it around the trailer yard coupling it to a load-trailer, or assisting with coupling the dolly to a lead-trailer. 
     Problems may be encountered when transporting trailers, and multiple linked dolly and trailer assemblies on railcars, and properly securing them to the railcar due to the securing points on the dollies and trailers being in unpredictable locations. 
     What is needed is the ability to maneuver dollies into alignment and coupling with load-trailers, and the ability to move the load-trailer dolly assembly into alignment and coupling with a lead-trailer, without requiring undue effort by an operator, or putting the operator and other personnel into a dangerous situation. In addition, what is needed is the ability to secure multiple trailer, and dolly and trailer assemblies to a railroad flatcar for intermodal transportation. 
     Heretofore there has not been available a converter dolly with the advantages and features of the disclosed subject matter. 
     SUMMARY OF THE INVENTION 
     A self-powered converter dolly suitable for highway transportation is provided for moving trailers around a yard, and for joining trailers with lead-trailers. The dolly includes a frame having one or more axles and wheels, a fifth wheel, and a drawbar and ring coupling. The drawbar may be fixed in relation to the dolly or pivot. A powered, steerable landing gear is attached to the drawbar of the dolly. The landing gear has a steering control module with a hydraulic leg extending therefrom attaching wheels. The steering control module controls the direction of the landing gear wheels, and the extending and retracting of the hydraulic leg for positioning the dolly ring coupling at the right height for connection with a lead-trailer. The wheels are connected to a motor that provides rotational movement to the wheels enabling the dolly to move under its own power, and to move an attached trailer around a trailer yard. The motor on the landing gear can be either hydraulically-powered or electrically-powered with the respective power source being located on the dolly. In addition, the dolly provides a compressed air source to operate the air brakes on the dolly and the load-trailer. 
     The dolly is controlled by an operator using a remote control enabling the operator to remain in a safe location away from the dolly and trailer when moving the dolly, connecting the dolly to a load-trailer, and when connecting a dolly and load-trailer assembly to a lead trailer. Moreover, the self-powered converter dolly allows one operator to safely maneuver the dolly around the trailer yard, and to couple the dolly and trailers together avoiding excessive physical strain and injury to personnel. 
     The steerable landing gear may be used with a dolly having power supplied to the wheels on the axles of the dolly instead of power supplied to the landing gear wheels. For dollies having only one axle, the pitch of the fifth wheel can be adjusted by a hydraulic cylinder that pushes the wheels of the landing gear into the ground allowing the wheels to have traction. Alternatively, the fifth wheel can be provided with a hydraulic scissor lift permitting an operator to move trailers around a trailer yard without needing to retract the landing gear on the trailer. 
     The dolly may be used with intermodal transportation systems utilizing railway flatcars providing an attachment point for securing the dolly to the railcar. The dolly may be secured to the railcar using a tie down such as a chain, ratchet load binder, hydraulic cylinder, a winch and cable, or a hitch and receiver component. 
     Alternatively a trolley system having a trolley with an adjustable receiver, and movable along the length of a railcar may be used to secure a dolly or trailer to an intermodal railcar. The trolley moves within a trolley guide attached to the railcar. The trolley is maneuvered into a position for attachment to a dolly or trailer and immobilized by inserting a pin into a hole in the trolley that aligns with a hole in the trolley guide. A circular receiver is then raised to the appropriate height to engage a circular hitch component attached to the dolly and is secured thereto. The receiver may then be further adjusted to prevent further movement of the dolly connected thereto. The trolley is also adapted to provide a fifth wheel type receiver for securing a trailer having a kingpin to a railcar. The trolley is further provided with several mechanisms and actuators for raising and lowering the receiver into position with a hitch. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawings constitute a part of this specification and include exemplary embodiments of the invention illustrating various objects and features thereof, wherein like references are generally numbered alike in the several views. 
         FIG. 1  is a perspective view of a powered converter dolly embodying principles of the disclosed subject matter where the drawbar pivots on the dolly frame, and the wheels on the landing gear are the powered drive wheels. 
         FIG. 2  is a plan view of the converter dolly of  FIG. 1 . 
         FIG. 3  is an elevation view of the converter dolly of  FIG. 1  with the landing gear extended. 
         FIG. 4  is an elevational view of the converter dolly of  FIG. 1  coupled to a load-trailer and a leading trailer, with the dolly landing gear retracted. 
         FIG. 5  is an elevational view of the converter dolly of  FIG. 4  attached to an intermodal railroad flatcar. 
         FIG. 6A  is an enlarged elevational view of the tie down mechanism taken generally within circle  6 A in  FIG. 5 . 
         FIG. 6B  is a sectional view of a tie down mechanism taken along the line  6 B in  FIG. 6A . 
         FIG. 6C  is an alternative tie down mechanism. 
         FIG. 6D  is another alternative tie down mechanism. 
         FIG. 6E  is another alternative tie down mechanism. 
         FIG. 6F  is another alternative tie down mechanism. 
         FIG. 7  is an alternative embodiment of a powered converter dolly embodying the principles of the disclosed subject matter where the wheels on the dolly axles are the powered drive wheels. 
         FIG. 8  is an alternative embodiment of a powered converter dolly embodying the principles of the disclosed subject matter where the drawbar has an extendable hydraulic jack. 
         FIG. 9  is an alternative embodiment of a powered converter dolly embodying the principles of the disclosed subject matter where the fifth wheel is hydraulically actuated showing the dolly backing under a load-trailer. 
         FIG. 10  is the dolly of  FIG. 9  connecting to a trailer. 
         FIG. 11  is the dolly of  FIG. 9  lifting a trailer for transport. 
         FIG. 12  is a perspective view of an alternative embodiment of a powered converter dolly embodying the principles of the disclosed subject matter where the drawbar is integrated with the dolly frame, and the wheels on the landing gear are the powered drive wheels. 
         FIG. 13  is a plan view of the converter dolly of  FIG. 12 . 
         FIG. 14  is an elevation view of the converter dolly of  FIG. 12  with the landing gear extended. 
         FIG. 15  is an elevational view of the converter dolly of  FIG. 12  coupled to a load-trailer and a leading trailer, with the dolly landing gear retracted. 
         FIG. 16  is an elevation view of the converter dolly of  FIG. 15  attached to an intermodal railroad flatcar. 
         FIG. 17A  is an enlarged elevational view of the tie down mechanism taken generally within circle  15 A in  FIG. 16 . 
         FIG. 17B  is an alternative tie down mechanism. 
         FIG. 17C  is another alternative tie down mechanism. 
         FIG. 17D  is another alternative tie down mechanism. 
         FIG. 17E  is another alternative tie down mechanism. 
         FIG. 18  is an alternative embodiment of a powered converter dolly embodying the principles of the disclosed subject matter where the wheels on the dolly axle are the powered drive wheels. 
         FIG. 19  is an alternative embodiment of a powered converter dolly embodying the principles of the disclosed subject matter where the drawbar has an extendable hydraulic jack. 
         FIG. 20  is a perspective view of the trolley system mounted on a railcar embodying principles of the disclosed subject matter. 
         FIG. 21  is a perspective view of the trolley of  FIG. 20 . 
         FIG. 22  is an elevational view of the dolly connected to a trailer on a railcar, and the trolley connected to the dolly. 
         FIG. 23  is an enlarged elevational view of the trolley connected to the dolly taken generally within circle  23  in  FIG. 22 . 
         FIG. 24  is an enlarged elevational view of the trolley connected to the dolly taken generally within circle  24  in  FIG. 22 . 
         FIG. 25  is a plan view of the trolley connected to a dolly on a railcar of  FIG. 22 . 
         FIG. 26  is an enlarged plan view of the trolley connected to a dolly on a railcar taken generally within circle  26  in  FIG. 25 . 
         FIG. 27  is a sectional view of the trolley and dolly on a railcar taken along the line  27  in  FIG. 22 . 
         FIG. 28  is an elevational view of an alternative embodiment trolley system embodying principles of the disclosed subject matter whereby the trolley is supporting a trailer with a fifth wheel trailer stand. 
         FIG. 29  is an elevational view of an alternative embodiment trolley system embodying principles of the disclosed subject matter whereby the trolley is securing a tractor with an adapter and chains. 
         FIG. 30  is an elevational view of the adapter without chains. 
         FIG. 31  is a plan view of the adapter without chains. 
         FIG. 32  is a sectional view of the adapter along the line  32  in  FIG. 31 . 
         FIG. 33  is an elevational view of an alternative embodiment trolley system embodying principles of the disclosed subject matter whereby the trolley is securing a tractor using a mount secured to the frame. 
         FIG. 34  is an elevational view of an alternative embodiment trolley system embodying principles of the disclosed subject matter whereby the trolley is supporting a trailer with a stanchion. 
         FIG. 35  is a perspective view of an alternative embodiment trolley system embodying principles of the disclosed subject matter whereby the trolley is using a scissor lift to raise and lower an adjustable hitch. 
         FIG. 36  is an elevational view of the trolley system of  FIG. 35 . 
         FIG. 37  is a plan view of the trolley of  FIG. 35 . 
         FIG. 38  is a perspective view of an alternative embodiment trolley system embodying principles of the disclosed subject matter whereby the trolley is using a scissor lift to raise and lower a mini fifth wheel hitch. 
         FIG. 39  is an elevational view of the trolley system of  FIG. 38 . 
         FIG. 40  is a plan view of the trolley of  FIG. 38 . 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     I. Introduction and Environment 
     As required, detailed aspects of the disclosed subject matter are disclosed herein; however, it is to be understood that the disclosed aspects are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art how to variously employ the present invention in virtually any appropriately detailed structure. 
     Certain terminology will be used in the following description for convenience in reference only and will not be limiting. For example, up, down, front, back, right and left refer to the invention as orientated in the view being referred to. The words, “inwardly” and “outwardly” refer to directions toward and away from, respectively, the geometric center of the aspect being described and designated parts thereof. Forwardly and rearwardly are generally in reference to the direction of travel, if appropriate. Said terminology will include the words specifically mentioned, derivatives thereof and words of similar meaning. 
     II. Embodiment of the Powered Converter Dolly  2   
     Referring to the drawings in more detail, the reference numeral  2  generally designates a powered converter dolly suitable for highway transportation embodying the principles of the disclosed subject matter. The dolly  2  generally consists of a rectangular frame  4  having one or more axle assemblies  18  depending therefrom, and mounting a hitch component  50 , such as a fifth wheel. An independent drawbar assembly  60  extends forward from the frame  4  and terminates at a ring coupling  70 . A steerable landing gear assembly  82  is attached to the drawbar assembly  60  providing powered movement and controlling the direction of movement of the dolly  2 . The dolly  2  may be attached to an object, such as a load-trailer  106 , for moving the trailer  106  around a trailer yard, or to connect the trailer  106  to a lead-trailer  105 . 
     Referring to  FIGS. 1-6F , an embodiment of the dolly  2  is shown and described having two axle assemblies  18  depending therefrom including wheels  28  and air brakes, and a powered, steerable landing gear assembly  82  attached to a movable drawbar assembly  60 . Referring to  FIGS. 1-3 , the dolly  2  is shown freestanding with the drawbar assembly  60  releasably secured to the frame  4 , and the landing gear assembly  82  in an extended position with landing gear wheels  98  engaging the ground. 
     The dolly  2  frame  4  may be manufactured from metal, preferably steel, and is generally rectangular in configuration having opposite side rails  6  extending forward and rearward along the length of the frame  4 . The side rails  6  are joined at the front end by a front rail  8 , and joined at the rear end by a rear rail  10  using a secure connection such as a weld, or by fasteners such as bolts. Cross members  12  span between the side rails  6  adding rigidity to the frame  4 , and permit mounting of the hitch component  50 , and accessories. A pair of axle assemblies  18  each having four ground engaging wheels  28  and air-powered brakes, depend from the frame  4 . The second hitch component  50  fifth wheel comprises a generally circular metal pickup plate  52  having an elongated, triangular-shaped slot  54  open at the rear for aligning a hitch component  114  such as the kingpin of a trailer  106  with the pickup plate  52 . The pickup plate  52  is pivotally mounted to the frame  4  by brackets  14 ,  15  allowing the pickup plate  52  to pitch forward or backward as needed to engage the hitch component  114 . The rear of the frame  4  may contain inclined ramps  16  for properly guiding a trailer  106  into engagement with the hitch component  50 . The front of the frame  4  has a pair of brackets  13  for rotatably mounting the drawbar assembly  60  to it. 
     The drawbar assembly  60  is manufactured from metal, preferably steel, and is generally triangular in configuration. The drawbar assembly  60  has two side rails  67  originating from the ends of a cross member  68  located nearest the frame  4 , and extends forward terminating at a ring coupling  70 . The ring coupling  70  is mounted at the forward most end of the dolly  2  for engagement with a coupling  110  on a lead-trailer  105 . The coupling  110  may include, but is not limited to a pintle hook coupling or a combination ball hitch. Lead-trailers  105  can have couplings  110  located at different heights above the ground. Therefore, the drawbar assembly  60  of the dolly  2  is rotatably mounted to the frame  4  by brackets  62 . Rotation of the drawbar assembly  60  with respect to the frame  4  enables engagement of the ring coupling  70  to couplings  110  located at different heights above the ground. Each of the brackets  13 ,  62  have removable lock-out pins  66  for preventing rotation of the drawbar assembly  60  with respect to the frame  4 . Preventing rotation of the drawbar assembly  60  allows rigid engagement of the landing gear assembly  82  with the ground, described in more detail below. Safety chains  72  located adjacent to the ring coupling  70  may be attached to a leading trailer  105  for added safety in case the trailer  105  and dolly  2  become uncoupled. 
     The landing gear assembly  82  is rotatably attached to the drawbar assembly  60  between the side rails  67  by a pivot shaft  92 , and generally consists of a steering control module  84  having a telescoping leg  94  projecting therefrom. Ground engaging wheels  98  at the distal end of the leg  94 , are powered by a drive motor  100  that causes the wheels  98  to rotate in both a clockwise and counterclockwise direction to provide movement to the dolly  2 . The type of motor  100  used may include, but is not limited to an electrically-powered, or hydraulically-powered motor. The steering control module  84  contains an actuator (not shown) for rotating the leg  94  and wheels  98  about a vertical axis for steering the dolly  2 , and an actuator (not shown) for extending and retracting the telescopic leg  94 . The aforementioned actuators may include, but are not limited to an electrical actuator or a hydraulic actuator. Another actuator  88  extends between the leg  94  and cross member  68  for moving the landing gear assembly  82  between an extended and retracted position. The aforementioned actuator  88  may include, but is not limited to an electric, hydraulic, or pneumatic actuator, preferably a hydraulic actuator. The actuator  88  attaches to the leg  94  and cross member  68  by brackets  96 ,  90 , respectively. 
     The dolly  2  is self-powered, providing power from one or more of the following power sources: hydraulic power from a hydraulic pump  44  and hydraulic reservoir  46 ; electrical power from a generator  38  and rechargeable batteries  36 ; and compressed air from an air compressor  30  and an air tank  32 . Hydraulic power may be provided to: the actuator  88  to extend and retract the landing gear assembly  82  between a ground-engaging position and a transportation position; the steering control module  84  to power the actuator that extends and retracts the telescopic leg  94 , and the actuator that rotates the leg  94  and wheels  98  for steering the dolly; and the drive motor  100  that provides movement to the wheels  98  for moving the dolly  2 . Electrical power is provided to operate the hydraulic pump  44 , air compressor  30 , and to recharge the batteries  36 . Alternatively, electrical power may be provided to electrical actuators in the steering control module  84 , to the actuator  88  on the leg  94 , or to an electrical drive motor  100 . The dolly  2  may incorporate any combination of hydraulic, pneumatic or electrical actuators or motors  100  as deemed necessary for a particular application. Compressed air may be provided to: the actuator  88  on the leg  94 ; the air brake system of the dolly  2 ; and for connection to the air-brake system of the load-trailer  106  for releasing the air brakes without the need for the trailer  106  to be connected to a tractor. 
     Referring to  FIG. 3 , the dolly  2  is shown connected to a load-trailer  106 . The dolly  2  has a remote control  102  containing a microcontroller and switches for controlling operation of: the landing gear assembly  82 ; actuator  88 ; the actuators in the leg  94  and steering control module  84 ; dolly  2  air brakes; and the hydraulic, pneumatic, or electrical power sources. The remote control  102  may include a safety feature that requires the operator to use both hands to operate the device, and an emergency off feature whereby the operator can cease all movement and activity of the dolly  2  and load-trailer  106  by rapidly engaging the air brakes of both. When not in use, the remote control  102  is securely stored within a storage box  74  located on the dolly  2 . The storage box  74  has a lid  76  that opens on hinges  78  by lifting on a handle  80 . A lengthy cord  104  connects the remote control  102  to the dolly  2  enabling an operator to position themselves out of danger, or into a better vantage point, when maneuvering the dolly  2  or an attached trailer  106 . 
     The dolly  2  is prepared for use in maneuvering a trailer  106  by inserting the lock-out pins  66  into the brackets  13 ,  62  to secure the drawbar assembly  60  to the frame  4  preventing their rotation thereabout. A rigid connection between the drawbar assembly  60  and frame  4  enables the wheels  98  of the landing gear assembly  82  to have fraction with the ground. Using the remote control  102 , an operator powers up the dolly  2  and extends the actuator  88  positioning the landing gear assembly  82  perpendicular to the drawbar assembly  60 , and the wheels  98  in contact with the ground. The motor  100  rotates the wheels  98  and moves the dolly  2  in the direction the wheels  98  are pointing. The dolly  2  is maneuvered underneath the trailer  106  enabling engagement of the hitch component  50  with the bearing plate  112 . The dolly  2  air brakes are then engaged. A supply line  65 , providing an electrical and air connection between the dolly  2  and trailer  16 , is connected allowing the operator to engage and disengage the air brakes on the trailer  106  using the air tank  32  on the dolly  2 . Once the operator releases the air brakes on the trailer  106  and dolly  2 , the motor  100  provides movement to the dolly  2  permitting the dolly  2  maneuver the trailer  106  around for repositioning or to connect the dolly  2  and trailer  106  assembly to a lead-trailer  105 . During movement, the dolly  2  and trailer  106  assembly can be stopped using either the air brakes on the dolly  2  or the trailer  106 . 
     Referring to  FIG. 4 , the dolly  2  is shown connected to a lead-trailer  105  with the landing gear assembly  82  in the highway transportation position. An operator aligns and connects the dolly  2  to a lead trailer  105  by positioning the ring coupling  70  in close proximity to the coupling  110  located on the bumper  108  of a lead trailer  105 . The operator engages the air brakes of the load-trailer  106 . The lock-out pins  66  are then removed and the leg  94  can retract to lower the ring coupling  70  onto a coupling  110  that is positioned low on the bumper  108 , or the leg  94  can be extended to raise the ring coupling  70  up to a coupling  110  that is positioned high on the bumper  108 . When the ring coupling  70  is securely engaged within the coupling  110 , the safety chains  72  are connected to the bumper  108 , and a supply line  64  is connected between the lead trailer  105  and the dolly  2  providing an electrical and air connection between the two trailers  105 ,  106 . The landing gear assembly  82  is removed from contact with the ground by retracting the actuator  88  thereby rotating the assembly  82  until the wheels  98  are underneath the rear of the drawbar assembly  60 . This positioning permits the necessary clearance between the ground and the wheels  98  when the trailers  105 ,  106  and dolly  2  are traveling roadways. The remote control  102  is returned to the storage box  74  during highway transportation. An electrical connection between the lead-trailer  105  and the dolly  2  can provide power for recharging the batteries  36  between uses. 
     The dolly  2  is disengaged from the lead trailer  105  by disconnecting the safety chains  72  and the supply line  64  between the lead trailer  105  and the dolly  2 , powering up the dolly  2 , engaging the air brakes of the following trailer  106  using the air supply from the dolly  2 , extending the actuator  88  until the wheels  98  are in contact with the ground, and extending the leg  94  to raise the ring coupling  70  off of the coupling  110 . The height of the drawbar assembly  60  is adjusted by extending and retracting the leg  94  to permit re-installation of the lock-out pins  66 . Once there is a rigid connection between the drawbar assembly  60  and the frame  4 , the operator can engage the motor  100  to move the dolly and trailer  106  away from the lead trailer  105 . 
     Referring to  FIGS. 5-6B , the dolly  2  is shown, with the landing gear assembly  82  retracted into the highway transportation position, attached to a lead-trailer  105  and a load-trailer  106 , on an intermodal railway flatcar  116 . A similar intermodal railway flatcar system using railway flatcars to transport trailers connected by dollies is found in U.S. Provisional Patent Application No. 61/247,397 to Banwart, filed Sep. 20, 2009, the contents of which are herein incorporated by reference in their entirety. A typical intermodal railway flatcar  116  assembly is shown having a deck  126  for supporting the dolly  2  and trailers  105 ,  106 . The railway flatcar  116  rides on a bogie  118  with wheels  122 . Typically a ramp  120  may span the railcar coupling  124  permitting one or more dolly  2  and trailer  106  assemblies to be driven onto two or more railway flatcars  116  while still being connected to a lead-trailer  105 . While one dolly  2  connecting two trailers  105 ,  106  is shown, one or more dollies and corresponding trailers may be jointed to create a lengthy “train” of trailers connected by dollies. The particular railway flatcar  116  shown has a channel  130  bound by rails  134  running down the middle for attaching and storing a tie down, such as a chain  132 . The tie downs attach at one end to the dolly  2  by a hook  133  at one or more attachment points such as a lashing ring, mounting ring, or an aperture  135  in the frame, and attach at the other end by a hook  133  to an aperture  143  in the rail  134 . The tie down secures the dolly  2  to the railway flatcar  116  while it is being transported on rail lines. When the intermodal railway flatcar  116  reaches a destination where the trailers  105 ,  106  are to be unloaded from the railway flatcar  116 , the tie down is disconnected from the attachment point  135  and remains with the railcar  116 . Thereafter, the dolly  2  and trailers  105 ,  106  can be driven off the railcars  116 . 
       FIGS. 6C-6F  show alternative types of tie downs that may be used to secure the dolly  2  to the railcar using the apertures  134  on the deck  126  of the railcar  116 , and the attachment points  135  on the dolly  2 . 
       FIG. 6C  shows a ratchet load binder  136  with hooks  133  securing the dolly  2  to the railcar  116  at the attachment point  135  and aperture  143 . 
       FIG. 6D  shows a hydraulic tie down, such as a hydraulic cylinder  138  secured at one end to the deck  126  and at the opposite end on the dolly  2 . 
       FIG. 6E  shows an electrical tie down secured at one end to the deck  126  and at the opposite end by a hook  133  to the attachment point  135  on the dolly  2 . 
       FIG. 6F  shows a first hitch component  164 , which may include, but is not limited to a ball hitch or a beveled lug, and a second hitch component  166 , such as a receiver. The hitch  164  is connected to the bottom of the frame  4  at a central location below the hitch component  50 . The receiver  166  is hydraulically actuated and is extended up from the channel  130  of the railcar  116  into contact with the hitch  164  and locking the hitch  164  to the receiver  166 . The receiver  166  is movable within the channel  130  enabling positioning of the receiver  166  along the length of the railcar  116 , and laterally to permit proper positioning of the tie down device. All of the tie downs remain with the railcar  116  and are not permanently attached to the dolly  2 . When in use, each tie down has one point of contact secured to the railcar  116 , and a second point of contact releasably secured to the dolly  2 . 
     III. First Alternative Embodiment Powered Converter Dolly  202   
     Reference numeral  202  generally designates an alternative embodiment powered converter dolly embodying the principles of the disclosed subject matter. Referring to  FIG. 7 , the dolly  202  is shown having a landing gear assembly  282  that is substantially similar to the landing gear assembly  82  described above except that it does not have a motor connected to the wheels  98 . Instead, the movement of the dolly  202  is by way of a motor  226  and differential  222  operably connected to the axle  19  of one of the two axle assemblies  18 . The motor  226  may be an electrical motor powered by the batteries  36  or generator  38 , or may be a hydraulic motor powered by the hydraulic pump  44 . Control of the motor  226  is by way of the aforementioned remote control  102 . Movement and control of the dolly  2  and landing gear assembly  82  is as described above. 
     IV. Second Alternative Embodiment Powered Converter Dolly  302   
     Reference numeral  302  generally designates a second alternative embodiment powered converter dolly embodying the principles of the disclosed subject matter. Referring to  FIG. 8 , the dolly  302  is shown having a landing gear assembly  82  and a hydraulic ram  330  attached to the top of the drawbar assembly  60 . The hydraulic ram  330  is powered by the hydraulic pump  44  and operated by the remote control  102 . The hydraulic ram  330  is extended to engage a receiver on the bumper  108  of a lead-trailer  105 , and retracted to draw the dolly  2  closer to a leading trailer  105  in order to align the ring coupling  70  with a coupling on the leading trailer&#39;s bumper. The hydraulic ram  330  may be used with or without the aid of the motors  226 ,  100  during this maneuver. 
     V. Third Alternative Embodiment Powered Converter Dolly  402   
     Reference numeral  402  generally designates a third alternative embodiment powered converter dolly embodying the principles of the disclosed subject matter. Referring to  FIG. 9 , the dolly  402  is shown with a hydraulic fifth wheel assembly  444  that allows an operator to move a trailer  106  without retracting the landing gear  107 . The assembly  444  consists of a fifth wheel  445  pivotally attached to a top plate  446 . The top plate  446  is attached to a bottom plate  448  by a pair of linked, folding support arms  450  arranged in a crisscross “X” pattern. An actuator  452 , such as a hydraulic cylinder, provides pressure against an arm  450  to raise and lower the fifth wheel  445 . The actuator  452  may be powered by the hydraulic pump  44  and operated by the remote control  102 . In operation, the dolly  402  is powered up and backed under a trailer  106 , using the remote control  102 , aligning the fifth wheel  445  with the hitch component  114  and bearing plate  112  on the trailer  106 . A supply line  64  is connected to the dolly  402  and the trailer  106  providing electrical power from the dolly  402  batteries  36  or generator  38  to the electrical system of the trailer  106 , and providing pneumatic power from the air tank  32  to the trailer enabling the operator to control the engagement and disengagement of the trailer  106  air brakes with the remote control  102 . After the trailer  106  air brakes have been engaged preventing the trailer  106  from rolling, the hydraulic fifth wheel assembly  444  is moved upward into contact with the bearing plate  112  ( FIG. 10 ) lifting the trailer up off of the ground ( FIG. 11 ) without having to retract the landing gear  107 . Once the landing gear  107  are off of the ground, the operator can release the air brakes on the trailer  106  and may then move the trailer using the powered dolly  402 . The trailer  106 , with landing gear  107  extended, may be left in a target location by lowering the hydraulic fifth wheel assembly  444  and bringing the landing gear  107  into contact with the ground. Thereafter, the supply line  64  can be disconnected and the dolly  402  may be used for other duties. 
     VI. Fourth Alternative Embodiment Powered Converter Dolly  502   
     Referring to  FIGS. 12-17E , the reference numeral  502  generally designates a fourth alternative embodiment powered converter dolly suitable for highway transportation embodying principles of the disclosed subject matter. The dolly  502  has many similarities to the dollies mentioned above. As such, the differences will be described below. 
     The dolly  502  generally consists of a rectangular frame  504  having a single axle assembly  18  depending therefrom, and mounting a hitch component  50  such as a fifth wheel. An integrated drawbar assembly  560  extends forward from the frame  504  and terminates at a ring coupling  70 . A steerable landing gear assembly  82 , as described above, is attached to the drawbar assembly  560 . 
     Referring to  FIGS. 12-14 , the dolly  502  is shown freestanding with the landing gear assembly  82  in an extended position with the wheels  98  engaging the ground. The dolly  502  frame  504  has opposite side rails  506 , a front rail  508 , a rear rail  510 , and cross members  512 . The frame  504  of the instant dolly  502  has only one axle assembly  18  depending therefrom including wheels  28  and air brakes. The dolly  502  includes a hitch component  50 , as described above, that is attached to the frame  504  by brackets  14 ,  15 . An actuator  558 , located on the frame  504  below the front of the fifth wheel, is for adjusting the pitch of the fifth wheel, described in more detail below. The rear of the frame  504  may contain inclined ramps  516  for properly guiding a trailer  160  thereon. 
     The dolly  502  frame  504  and drawbar assembly  560  are manufactured from metal, preferably steel. The drawbar assembly  560  is generally triangular in configuration and has two side rails  567  that originate from the ends of the front rail  508 , and extend forward terminating at a ring coupling  70 . 
     The landing gear assembly  82  is the same as described above however, the rear of the actuator  88  is attached by a bracket  90  to the forward face of the front rail  508 . 
     The instant dolly  502  is self-powered just as the dollies above, having the same power sources: a hydraulic pump  44  and reservoir  46 ; an electrical generator  38  and rechargeable batteries  36 ; and an air compressor  30  and air tank  32 . Hydraulic, pneumatic, and electrical power are supplied to the same components for the same reasons as described above, including hydraulic, pneumatic, or electrical power to the actuator  58 . 
     Referring to  FIG. 14 , the dolly  502  is shown connected to a load-trailer  106 . Because the dolly  502  has only one axle assembly  18  to bear the weight of the load-trailer  106 , the load-trailer  106  has a tendency to cause the front of the drawbar  560  to pitch up. Therefore, the actuator  558  is used to bias against the bottom of the fifth-wheel causing the landing gear assembly  82  to be pushed down toward the ground, in turn, bringing the wheels  98  into contact with the ground. The actuator  558  may be either a hydraulic cylinder, a pneumatic cylinder, or an electrical actuator, and is powered by the appropriate power source on the dolly  502 . As the actuator  558  is extended, the wheels  98  are pushed into the ground with greater force permitting the wheels  98  to have enough traction on the ground to allow the landing gear assembly  82  to steer, or the motor  100  to move, the load-trailer  106 . Control and operation of the actuator  558  and the mechanical components of the dolly  502  is via the remote control  102 . The remote control  102  in this embodiment is used and stored in the same manner as describe above. 
     The dolly  502  is prepared for use in maneuvering a trailer  106  by the operator using the remote control  102  to power up the dolly  502 . The landing gear assembly  82  is rotated into position by extending the actuator  88 . The operator engages the motor  100  rotating the wheels  98  and moving the dolly  502  in the direction the wheels  98  are pointing. The dolly  502  is maneuvered underneath the trailer  106  enabling engagement of the fifth wheel with the bearing plate  112 . The air brakes on the dolly  502  are engaged and a supply line  64  is connected between the trailer  106  and dolly  502  providing an electrical and air connection between the dolly  502  and trailer  106  allowing the operator to engage and disengage the air brakes on the trailer  106  using the air tank  32  on the dolly  502 . The operator then adjusts the actuator  558  to push the landing gear assembly  82  into the ground in order to give the wheels  98  enough fraction to effectively steer the trailer  106  and allow the motor  100  to rotate the wheels  98  for moving the load-trailer  106 . Once the operator releases the air brakes on the load-trailer  106  and dolly  554 , the motor  100  rotates the wheels  98  permitting the dolly  502  to maneuver the load-trailer  106  around for repositioning or to connect the dolly  502  and load-trailer  106  assembly to a lead-trailer  105 . During movement, the dolly  502  and load-trailer  106  assembly can be stopped using either the air brakes on the dolly  502  or the load-trailer  106 . 
     Referring to  FIG. 15 , the dolly  502  is shown connected to a lead-trailer  105  with the landing gear assembly  82  in the highway transportation position. The dolly  502  is attached to the lead-trailer  105  as described above. The ring coupling  70  is positioned at the right height by extending and retracting either the leg  94  or the actuator  558 . A supply line  64  is connected between the lead-trailer  105  and the dolly  502  as described above. The landing gear assembly  82  is moved into highway transportation position by retracting the actuator  88  until the wheels  98  are underneath the rear of the drawbar assembly  560 . The actuator  558  is retracted sufficiently to permit the fifth wheel to pitch forward and backward as needed when the dolly  502  is traveling over the roadway. Disengaging the dolly  502  from the lead-trailer  105  is accomplished by following the steps above in reverse. The remote control  102  is returned to the storage box  74  during highway transportation. As above, the lead-trailer  105  can recharge the rechargeable batteries  36  between uses. 
     Referring to  FIG. 16 , the dolly  502  is shown in the highway transportation position attached to a lead-trailer  105  and a load-trailer  106  on an intermodal railway flatcar  116 . The railway flatcar  116  and its assorted components are as described above. The dolly  502  is shown secured to the railcar  116  by a tie down, such as a chain  132 . As above, the tie downs attach to the dolly  502  at one or more attachment points such as a lashing ring, mounting ring, or an aperture  535  in the frame  504 , and remain with the railway flatcar  116  when not connected to the dolly  502 .  FIGS. 17A-17E  shown alternative types of tie downs that may be used including a mechanical tie-down, such as a ratchet load binder  136 , a hydraulic tie down, such as a hydraulic cylinder  138 , an electrical tie down, such as an electrical winch  140  and cable  141 , and a hitch  164  attached to the axle  19  of the axle assembly  18  and receiver  166 , each of which operate as described above. The aforementioned tie downs operate in the same manner as described in  FIGS. 6A-6F  described above. 
     VII. Fifth Alternative Embodiment Powered Converter Dolly  602   
     Reference numeral  602  generally designates a fifth alternative embodiment powered converter dolly embodying the principles of the disclosed subject matter. Referring to  FIG. 18 , the dolly  602  is shown having a landing gear assembly  682  that does not have a motor connected to the wheels  98  but has movement by way of a motor  626  and differential  622  operably connected to the axle  19  of the axle assembly  18 . The motor  626  and differential  622  are of the type, and operate in the same manner, as described above. 
     VIII. Sixth Alternative Embodiment Powered Converter Dolly  702   
     Reference numeral  702  generally designates a sixth alternative embodiment powered converter dolly embodying the principles of the disclosed subject matter. Referring to  FIG. 19 , the dolly  702  is shown having a landing gear assembly  82  and a hydraulic ram  730  attached to the top of the drawbar assembly  560 . The hydraulic ram  730  is of the same type, and operates in the same manner, as the hydraulic ram  330  described above. 
     It will be appreciated that the components of the dollies  2 ,  202 ,  302 ,  402 ,  502 ,  602 , and  702  may be used for various other applications. Moreover, the dollies may be fabricated in various sizes and from a wide range of suitable materials, using various manufacturing and fabrication techniques. 
     IX. Embodiment of the Trolley System  802   
     Reference numeral  802  generally designates a trolley system embodying the principles of the disclosed subject matter. Referring to  FIGS. 20-27 , the trolley system  802  is shown and described. In particular, the trolley system  802  has a trolley  804  movable on a railcar  116  within a trolley guide  840 , and has a hitch component  822  movable within a frame  806 . The hitch component  822  is selectively interconnectable with a hitch component  864  attached to an object including, but not limited to a dolly  2 ,  202 ,  302 ,  402 ,  502 ,  602 , and  702 , a trailer  105 ,  106 , a fifth wheel stand  952 , a connector ring  1062 , or a tractor  1086 . 
     Referring to  FIG. 21 , the trolley  804  generally consists of a frame  806  having an interior and an exterior whereby the interior is bounded by opposite end walls  808 , side walls  810 , and a bottom wall  812 . A flange  814  extends laterally from each side wall  810  overlapping a channel  842  of the trolley guide  840 . The flange  814  has a plurality of equally spaced receivers  816  that align with receivers  844  in the trolley guide  840 . The receivers  816 ,  844  are adapted for receiving a locking member such as an elongated pin  834 . A plurality of equally spaced wheels  818  are on the exterior of each side wall  810 , and are adapted for rolling within the channel  842 . 
     The hitch component  822  may be selectively positioned at any point along the length or width of the trolley  804  using one or more horizontal actuators. The horizontal actuators may be a longitudinal actuator  824  or a transverse actuator  826 . The hitch component  822  may be positioned along the length of the trolley  804  by adjusting the longitudinal actuator  824 . The actuator  824  may be operated using an arm crank  832  located at one end wall  808  of the trolley  804 , or by engaging a motor  830  located at the opposite end wall  808 . The hitch component  822  may be positioned at any point along the width of the trolley  804  by adjusting the transverse actuator  826 . The actuator  826  operates by engaging a motor  830  located at one end wall  808  of the trolley  804 , or by using an arm crank  832  located at the opposite end wall  808 . The arm cranks  832  and motors  830  may be locked down or locked-out to prevent unwanted movement of the hitch component  822 . The motor  830  may be a hydraulic, pneumatic, or electric motor powered by a complimentary power source. Alternatively, the actuators  824 ,  826  that move the hitch component  822  may be a roller pinion system such as the type manufactured by Nexen Group, Inc. of Vadnais Heights, Minn. 
     The hitch component  822  selectively interconnects with a second hitch component, such as a hitch  864 . The hitch component  822  is adapted to receive the hitch  864  and lock the two securely together using conventional locking devices known in the hitch industry. The hitch component  822  may include, but is not limited to a circular receiver having a bell-shaped opening. The hitch  864  may include, but is not limited to a king pin or a cylindrical object such as a ball hitch or a beveled lug. 
     Referring to  FIGS. 22-27 , the trolley  804  is shown connected to dollies  2  and trailers  106  mounted on railcars  116 . Although the trolley  804  is shown connected to a dual-axle dolly  2 , use of a dual-axle dolly  2  is intended to be exemplary and does not limit the scope of suitable dollies that may be used with the trolley system  802 . Therefore, the trolley  804  may be used with the dollies  2 ,  202 ,  302 ,  402 ,  502 ,  602 , and  702  described above, or other types of multi-axle dollies. Referring to  FIGS. 22 and 23 , the trolley  804  is shown connected to a dual-axle dolly  2 , and secured to one railcar  116 . The trolley  804  attaches to the dolly  2  by connecting the hitch component  822  to a hitch  864 . The hitch  864  may be generally located below the hitch component  50  and connected to the frame  4  by a mount  862 . Once the dolly  2  and trailer  106  are positioned on top of the railcar  116 , the trolley  804  is moved along the length of the railcar  116  within the trolley guide  840  to position the interior of the trolley  804  generally underneath the hitch  864 . The receivers  816 ,  844  are aligned on at least one railcar  116 . In the particular application depicted in  FIG. 23 , because the location of the hitch  864  is so close to the gap between two separate railcars  116 , the trolley  804  spans the gap. The multitude of wheels  818  on the trolley  804  enable it to remain in contact with at least one railcar  116  when in use, even when spanning two railcars  116 . After generally positioning the trolley  804 , at least one pair of locking members  834  are inserted into the receivers  816 ,  844  on either end of the trolley  804  to create a secure connection between the trolley  804  and the railcar  116 . The hitch component  822  is then positioned below the hitch  864  by adjusting the longitudinal actuator  824  and the transverse actuator  826 . When the hitch component  822  and hitch  864  align, the hitch component  822  is raised into engagement with the hitch  864  by the height actuator  828  securing the dolly  2  to the railcar  116 . The height actuator  828  is powered by a complimentary power source and may include, but is not limited to a hydraulic or pneumatic piston and cylinder unit, a scissor lift, a screw-type actuator such as the RACO screw electric actuator manufactured by RACO International, LP of Bethel Park, Pa., or an assembled columnar actuator such as the I-Lock Spiralift manufactured by PACO Spiralift, Inc. of Quebec, Canada. When the dolly  2  and trailer  106  are ready to be removed from the railcar  116 , the hitch component  822  and hitch  864  are disengaged and the hitch component  822  is retracted back into the trolley  804  so it does not obstruct passage of the dolly  2  or trailer  106  above, or contact any obstructions depending therefrom such as a hitch  864 . The trolley  804  may be repositioned by removing the locking members  834  and moving the trolley  804  along the length of the railcar  116 . The trolley  804  may remain with the railcar  116  when not in use. 
     Referring to  FIGS. 24 and 26 , the trolley  804  is shown connected to a dolly  2  as described above however, the trolley  804  is located entirely on one railcar  116  therefore, two pairs of locking members  834  at either end of the trolley  804  are used to secure the trolley  804  to the railcar  116 . 
     The trolley  804  described above has been shown connected to a dolly however, the trolley  804  may be connected to any suitable object having a hitch  864  depending therefrom including, but not limited to a tractor, a trailer, or an accessory. An accessory may include, and is not limited to a fifth wheel stand  952 , or a connector ring  1062 . 
     X. First Alternative Embodiment Trolley System  902   
     Reference numeral  902  generally designates a first alternative embodiment trolley system embodying the principles of the disclosed subject matter. Referring to  FIG. 28 , the trolley system  902  is shown and described including a trolley  904  having a fifth wheel stand  952  that may support the forward end of a lead-trailer  105 . A fifth wheel plate  954  is located at the top of the stand  952  for receiving the bearing plate  112  and hitch component  114  on the trailer  105 . The plate  954  is connected to the trolley  904  by four elongated support members  956  depending, and equally spaced at the periphery of the plate  954 . The opposite end of the supports  956  are received within the receivers  816  in the flange  814 . A hitch  864 , centered below the plate  954 , is connected to each of the supports  956  by brackets  958 . The hitch component  822  is positioned below the hitch  864  as described above and attaches to the hitch  864  securing the stand  952 , and in turn the trailer  105  to the trolley  202 . The trolley  904  may be movable on the railcar  116  within a trolley guide  840 , and secured to the railcar using the locking members  834  as described above. 
     XI. Second Alternative Embodiment Trolley System  1002   
     Reference numeral  1002  generally designates a second alternative embodiment trolley system embodying the principles of the disclosed subject matter. Referring to  FIGS. 29-32 , the trolley system  1002  is shown and described including a trolley  1004  securing an object, such as a tractor  1086  to a railcar  116  using a connector ring  1062 . The connector ring  1062  is a circular mushroom-shaped device having a hitch  1064 , similar to the hitch  864  described above, depending from the center. A plurality of slots  1066  radiate out from the top of the body  1065  providing an attachment point for the links of a chain  1072  hanging below the frame  1088  of the tractor  1086 . A plurality of eyelets  1068  located at the edge of the body  1065  are provided for receiving hooks (not shown) that may be attached to the end of the chains  1072 . The connector ring  1062  is mounted by either first attaching the ring  1062  to the chains  1072 , or by attaching the ring  1062  to the trolley  1004 . When first attaching the ring  1062  to the chains  1072 , three or more chains  1072  are equally spaced apart and connected to the slots  1066  or eyelets  1068  in the connector  1062 . The trolley  1004  is then positioned below the hitch  1064  and attached in the manner described above. When first attaching the ring  1062  to the trolley  1004 , the hitch  1064  is placed in the hitch component  822  and the ring  1062  is raised to a height below the frame  1088  to enable the chains  1072  to be properly connected. When the chains  1072  are connected, the hitch component  822  is drawn down toward the trolley  1004  securing the tractor  1086  to the railcar  116 . The trolley  1004  may be movable on the railcar  116  within a trolley guide  840 , and secured to the railcar  116  using the locking members  834  as described above. 
     XII. Third Alternative Embodiment Trolley System  1102   
     Reference numeral  1102  generally designates a third alternative embodiment trolley system embodying the principles of the disclosed subject matter. Referring to  FIG. 33 , the trolley system  1102  is shown and described including a trolley  1104  securing a tractor  1086  to a railcar  116  using a hitch  864  directly attached to the frame  1088  of the tractor  1086  by a mount  862 . The trolley  1104  operates in the same fashion as the trolley system  802  described above when positioning the trolley  1104  along the railcar  116  using the trolley guide  840 , and securing the tractor  1086  to the railcar  116 . 
     XIII. Fourth Alternative Embodiment Trolley System  1202   
     Reference numeral  1202  generally designates a fourth alternative embodiment trolley system embodying the principles of the disclosed subject matter. Referring to  FIG. 34 , the trolley system  1202  is shown and described including a trolley  1204  having a collapsible stanchion  1276  for supporting an end of a trailer  105  having a hitch component  114 . The trolley  1204  is generally of the same construction as the trolley  804  above without the hitch component  822  and the associated actuators and hardware supporting the hitch component  822  operation. The instant trolley  1204  has a stanchion  1276  supported by vertical and angular supports  1280  mounting a stanchion plate  1278 . The stanchion plate  1278  is laterally self aligning and operates in the same manner as the hitch component  50  described above for receiving the bearing plate  112  and the hitch component  114  of a trailer  105 . The trolley  1204  may be movable along the railcar  116  using the trolley guide  840 , and secured to the railcar  116  using the locking members  834  as described above. The trolley  1274  may remain with the railcar  116  when not in use. 
     XIV. Fifth Alternative Embodiment Trolley System  1302   
     Reference numeral  1302  generally designates a fifth alternative embodiment trolley system embodying the principles of the disclosed subject matter. Referring to  FIGS. 35-37 , the trolley system  1302  is shown and described including a trolley  1304  using a scissor lift  1326  to raise and lower a hitch component  1322 . The trolley  1304  is shown absent the trolley guide  840 , however the instant trolley  1304  moves within the trolley guide  840  in the same manner as the trolleys mentioned above. The scissor lift  1326  is designed and functions in a similar manner to a conventional scissor lift using an actuator  1330  to bias against the lifting structure to raise and lower a frame  1328 . The actuator  1330  is powered by a complimentary power source and may comprise the types of actuators used in conjunction with the height actuator  828  described above. Alternatively, the frame  1328  may be raised and lowered using the I-Lock Spiralift described above. The hitch component  1322  is laterally adjustable by rotating a shaft  1340  having a gear  1338  against a worm gear shaft  1336 . The hitch component  1322  is connected to the worm gear shaft  1356  by a collar  1346 . The collar  1346  pivots on the arm  1332  when the hitch component  1322  is moved laterally. The arm  1332  is connected to the frame  1328  by a crossbar  1348  having a pin  1334 . The pin  1334  permits the arm  1332  and hitch component  1322  to rotate thereabout. The shaft  1340  may be rotated by a hand crank, electric motor, or an air ratchet to align the hitch component  1322  with a hitch  864 . A pair of rods  1344  for capturing the hitch  864  within the hitch component  1322  are spring loaded to engage the hitch  864 . A lockout lever  1342  has a cam that is rotated to separate the rods  1344  for disengaging the hitch component  1322  and hitch  864  ( FIG. 37 ). The trolley  1304  may be secured to the railcar using the locking members  834  as described above. 
     XV. Sixth Alternative Embodiment Trolley System  1402   
     Reference numeral  1402  generally designates a sixth alternative embodiment trolley system embodying the principles of the disclosed subject matter. Referring to  FIGS. 38-40 , the trolley system  1402  is shown and described including a trolley  1404  using a scissor lift  1326  to raise and lower a mini-fifth wheel hitch  1412 . The scissor lift  1326  is designed and functions in a similar manner as above, and is used to raise and lower a platform  1420  having a mini fifth wheel hitch  1412  attached. The fifth wheel hitch  1412  has a pickup plate  1414  with a slot  1416  for receiving the kingpin of a trailer. The fifth wheel hitch  1412  is pivotally attached to a base plate  1418 . The base plate  1418  is movable along the length of the platform  1420  within an elongated aperture  1422  disposed within the platform  1420 . A pivot pin  1424  at the rear of the base plate  1418 , and a guide pin  1426  extending from the lever  1428  at the front of the base plate  1418 , guide the base plate  1418  along the aperture  1422 . Because the kingpin on a trailer may not perfectly align with the center of the platform  1420 , the fifth wheel hitch  1412  may freely move laterally within a curved aperture  1430  in the base plate  1418 , pivoting about the pivot pin  1424 , to self align when being positioned beneath a trailer and capturing the kingpin. When the fifth wheel hitch  1412  engages the kingpin, a lever  1428 , having a guide pin  1426  that passes through the platform  1420  and base plate  1418 , may be rotated to create a camming force to press the platform  1420  and plate  1418  together to immobilize the base plate  1418  locking the fifth wheel hitch  1412  in place. A lock out pin  1432  extends across the slot  1416  and may be manually operated to secure the kingpin within the slot  1416 . The trolley  1404  may be movable along the railcar  116  using the trolley guide  840 , and secured to the railcar using the locking members  834  as described above. 
     It will be appreciated that the components of the aforementioned trolley systems  802 ,  902 ,  1002 ,  1102 ,  1202 ,  1302 , and  1402  may be used for various other applications. Moreover, the trolley systems may be fabricated in various sizes and from a wide range of suitable materials, using various manufacturing and fabrication techniques. 
     It is to be understood that while certain aspects of the disclosed subject matter have been shown and described, the disclosed subject matter is not limited thereto and encompasses various other embodiments and aspects.