Patent Publication Number: US-9834333-B1

Title: Offshore cargo rack for use in transferring palletized loads between a marine vessel and an offshore platform

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is a continuation of U.S. patent application Ser. No. 14/317,026, filed 27 Jun. 2014 (issued as U.S. Pat. No. 9,216,841 on 22 Dec. 2015), which claims benefit of U.S. Provisional Patent Application Ser. No. 61/840,453, filed 27 Jun. 2013, which is hereby incorporated herein by reference. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable 
     REFERENCE TO A “MICROFICHE APPENDIX” 
     Not applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to cargo racks for transferring goods between marine vessels and offshore platforms such as oil and gas well drilling and production platforms. More particularly, the present invention relates to an improved cargo rack that enables a user to load the rack with multiple palletized loads (or other loads) and to then transport the entire rack using a lifting device such as a crane or a forklift from the marine vessel to the platform. 
     2. General Background 
     In the exploration of oil and gas in a marine environment, fixed, semi submersible, jack up, and other offshore marine platforms are used during drilling operations. Fixed platforms are typically used for production of oil and gas from wells after they have been drilled. Drilling and production require that an enormous amount of supplies be transported from land based storage facilities. Supplies are typically transferred to offshore platforms using very large marine vessels called work boats. These work boats can be in excess of one hundred feet in length and have expansive deck areas for carrying cargo that is destined for an offshore platform. Supplies are typically transferred from a land based dock area to the marine vessel using a lifting device such as a crane or a mobile lifting and transport device such as a forklift. 
     Once a work boat arrives at a selected offshore platform, supplies or products are typically transferred from the deck of the work boat to the platform using a lifting device such as a crane. 
     Once on the deck of a drilling platform or production platform, space is at a premium. The storage of supplies on an offshore oil well drilling or production platform is a huge problem. 
     Many cargo transport and lifting devices have been patented. The table below lists some patents, each of which is incorporated herein by reference, that relate generally to pallets, palletized racks, and other cargo racks: 
     
       
         
           
               
               
               
             
               
                 TABLE 1 
               
               
                   
               
               
                   
                   
                 Issue Date 
               
               
                 Pat. No. 
                 Title 
                 MM-DD-YYYY 
               
               
                   
               
             
            
               
                 2,579,655 
                 Collapsible Container 
                 Dec. 25, 1951 
               
               
                 2,683,010 
                 Pallet and Spacer 
                 Jul. 6, 1954 
               
               
                 3,776,435 
                 Pallet 
                 Dec. 4, 1973 
               
               
                 3,916,803 
                 Loading Platform 
                 Nov. 14, 1975 
               
               
                 4,165,806 
                 Palletizing System for Produce  
                 Aug. 28, 1979 
               
               
                   
                 Cartons and the Like 
                   
               
               
                 4,403,556 
                 Drum Retainer 
                 Sep. 13, 1983 
               
               
                 4,828,311 
                 Metal Form Pallet 
                 May 9, 1989 
               
               
                 5,078,415 
                 Mobile Carrier for Gas Cylinders 
                 Jan. 7, 1992 
               
               
                 5,156,233 
                 Safety Anchor for Use with Slotted Beams 
                 Oct. 20, 1992 
               
               
                 5,292,012 
                 Tank Handling and Protection Structure 
                 Mar. 8, 1994 
               
               
                 5,507,237 
                 Lifting Apparatus for Use with Bulk Bags 
                 Apr. 16, 1996 
               
               
                 5,906,165 
                 Stackable Tray for Plants 
                 May 25, 1999 
               
               
                 6,058,852 
                 Equipment Skid 
                 May 9, 2000 
               
               
                 6,357,365 
                 Intermediate Bulk Container Lifting Rack 
                 Mar. 19, 2002 
               
               
                 6,371,299 
                 Crate Assembly and Improved Method 
                 Apr. 16, 2002 
               
               
                 6,422,405 
                 Adjustable Dunnage Rack 
                 Jul. 23, 2002 
               
               
                 6,668,735 
                 Pallet with a Plastic Platform 
                 Dec. 30, 2003 
               
               
                 6,725,783 
                 Pallet for Stacking Planographic Printing 
                 Apr. 27, 2004 
               
               
                   
                 Plates Thereon 
                   
               
               
                 6,983,704 
                 Offshore Cargo Rack for Use in Trans- 
                 Jan. 10, 2006 
               
               
                   
                 ferring Palletized Loads Between A 
                   
               
               
                   
                 Marine Vessel And An Offshore Platform 
                   
               
               
                 7,997,214 
                 Offshore Cargo Rack for Use in Trans- 
                 Aug. 16, 2011 
               
               
                   
                 ferring Palletized Loads Between A 
                   
               
               
                   
                 Marine Vessel And An Offshore Platform 
               
               
                   
               
            
           
         
       
     
     BRIEF SUMMARY OF THE INVENTION 
     The present invention provides an improved cargo rack apparatus that includes a frame having a front, a rear, side walls, and upper and lower end portions. 
     The lower end portion of the frame provides a base that can have preferably a plurality of beams that arc welded together. The base can have a floor. 
     A pair of open-ended parallel forklift tine tubes or sockets can be provided on the base. 
     The frame preferably includes side walls that extend upwardly from the base including at least left and right side walls. There can be front and rear gated end walls. 
     Each gate can be movable between open and closed positions. The gates enable a forklift to place loads on the floor by accessing either the front or the rear of the frame. 
     The present invention includes a cargo rack comprising a frame having a base, a front, a rear, and upper and lower end portions. The base of the frame can have a perimeter and a floor providing multiple load holding positions, each configured to hold a load module. A plurality of load modules can be supported with the frame during use. The frame can include a plurality of side walls that attach to and extend upwardly from the perimeter beam base and including at least left and right side walls, first and second frame ends, the frame having four corners with a corner column at each corner. Each side can have at least one intermediate column positioned in between two corner columns. The upper end portion of each side wall can have an upper horizontal beam that connects the upper end of each corner column to each intermediate column. A plurality of gates can be movably mounted to the frame, each gate being movably attached to a side wall between open and closed positions, each gate spanning across a said end in a horizontal direction from one corner column to another corner column. Multiple reinforcements can connect each intermediate column to corner columns on the side walls, including reinforcing beams that extend between a corner column and an intermediate column at a position in between the base and the upper horizontal beam. The reinforcements can include a diagonally extending beam that extends from the top of a said corner column downwardly to a position next to the lower end of a said intermediate column. A plate can connect the lower end of a said diagonal member to both the base and a said intermediate column. Wherein the gates can enable a module to be removed laterally with a fork lift when a selected said gate is in the open position and without removing the other module. 
     In one embodiment, there can be two load holding positions. 
     In one embodiment, the present invention can further comprise a laterally extending beam on each side that can extend from a corner column to a diagonally extending beam. 
     In one embodiment, there can be a drain opening in the floor on one of the load holding positions. 
     In one embodiment, there can be a plate opening. 
     In one embodiment, the present invention can further comprise a pair of tanks, one on each load holding position. 
     In one embodiment, the present invention can further comprise a dividing beam that one load holding position separates from the other. 
     The present invention can provide a cargo rack that includes a frame having a base with a base perimeter that includes a plurality of beams, a front, a rear, upper and lower end portions, the frame holding at least a pair of load modules. The frame can include a plurality of side walls and end walls extending upwardly from the base at the base perimeter and including at least left and right side walls, four corners that each provide a corner column and an intermediate column spaced in between two said corner columns. The upper portion of each side wall can have an upper horizontal beam that connects the upper end of each corner column to each intermediate column. The end walls can be gates that are movably mounted to the frame, each gate being movable between open and closed positions, each gate extending between two corner columns. Multiple reinforcements can connect each intermediate column to corner columns on said side walls, including reinforcing beams that extend both horizontally and diagonally between a corner column and an intermediate column at a position in between the base and the upper horizontal beam. A plate can connect the lower end of a said diagonal member to both the base and a said intermediate column. Wherein the gates can enable any one of the load modules to be removed laterally with a fork lift when a selected said gate is in the open position and without removing any other module. 
     In one embodiment, there can be a gate at each end of the frame. 
     In one embodiment, there can be multiple diagonally extending beams that intersect multiple horizontally extending beams. 
     In one embodiment, the floor can include inclined portions. 
     In one embodiment, there can be a drain in the floor. 
     In one embodiment, the floor can attach to the perimeter beams. 
     In one embodiment, the floor can attach to the upper end portion of at least one of the perimeter beams. 
     In one embodiment, the present invention further comprises a vertical support next to each corner column that can be mounted to the base and that can connect at intervals to the said corner column. 
     In one embodiment, there can be multiple hinge mounts that attach to both a said corner column and a said vertical support. 
     The present invention provides a cargo rack that can include a frame that can have a base with a floor, a front, a rear, upper and lower end portions. A plurality of load modules can be supported within the frame and upon the floor during use. The frame includes a plurality of side walls extending upwardly from the base including at least left and right side walls, the frame having four corners, corner column at each corner and at least one intermediate column connected to the base and positioned in between two corner columns. The upper end portion of each side wall can have an upper horizontal beam that connects the upper end of each corner column to each intermediate column. A plurality of gates can be movably mounted on the frame at a said frame end, each gate being movable between open and closed positions, the gates enabling the load modules to be loaded laterally to the floor when a said gate is opened. Multiple reinforcements can connect each intermediate column to corner columns on side walls, including reinforcing beams that extend between a corner column and an intermediate column at a position in between the base and the upper horizontal beam and multiple diagonal beams that each connect to a reinforcing beam and to a said column. The floor can have a plurality of load holding positions. Wherein the gates enable any one of the modules to be removed laterally with a fork lift when a said gate is opened, and wherein no other module is moved. 
     In one embodiment, each corner column can be supported by a vertical support attached to the floor. 
     In one embodiment, the vertical support can attach to the corner column at intervals. 
     In one embodiment, the floor can be inclined. 
     In one embodiment, the intermediate column can be connected to the diagonally extending beam with a plate. 
     In one embodiment, the plate can have horizontal and vertical components. 
     In one embodiment, the plate can have an opening. 
     In one embodiment, the present invention can further comprise one or more transverse beams that can connect the intermediate columns. 
     In one embodiment, the present invention can further comprise raised pedestals that can extend above the floor for providing indexing for receipt of a load placed on a load holding position of the frame. 
     The present invention includes a method of transporting load modules, comprising the steps of providing a frame having a base with a floor, a front, a rear, and upper and lower end portions, and a pair of open ended parallel fork lift tine sockets, the frame can include a plurality of side walls extending upwardly from the base and including at least left and right side walls, the side walls can have corner columns and intermediate columns, each intermediate column can be position in between two corner columns. The upper end portion of each side wall can have an upper horizontal beam that connects the upper end of each corner column to each intermediate column. A plurality of gates can be mounted to the frame, each spanning between two corner columns, each gate being movable between open and closed positions, the open position of each gate providing an open doorway, the gates enabling a fork lift to place a selected one of the load modules on the floor by moving the selected load module laterally through a said open doorway. Multiple reinforcement can connect each intermediate column to corner columns on the side walls, including reinforcing beams that extend between a corner column and an intermediate column at a position in between the base and the upper horizontal beam and multiple diagonal beams. The floor can have a plurality of load holding positions, each having one or more restraints that both vertically and laterally hold a load module in position once the load is placed on the floor. Wherein the present invention can include the gates exposing a majority of the width of the floor for loading when opened. The gates can enable removal of any one of the four modules laterally with a fork lift when a said gate is opened and without removing any other module. Each diagonal beam can be connected to both the floor and a said intermediate beam with a plate. 
     In one embodiment, there can be a pair of gates. 
     In one embodiment, there can be horizontal and vertical components of said plate. 
     In one embodiment, the floor can be at least partially inclined. 
     In one embodiment, there can be a plate opening in the plate. 
     In one embodiment, the plate can attach to the floor at a position spaced away from an intermediate beam. 
     In one embodiment, the present invention can further comprise lift eyes on the corner columns. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein: 
         FIG. 1  is a side elevation view of a preferred embodiment of the apparatus of the present invention taken along lines  1 - 1  of  FIG. 2 ; 
         FIG. 2  is a plan view of a preferred embodiment of the apparatus of the present invention taken along lines  2 - 2  of  FIG. 1 ; 
         FIG. 3  is an end view of a preferred embodiment of the apparatus of the present invention taken along lines  3 - 3  of  FIG. 2 ; 
         FIG. 4  is an end view of a preferred embodiment of the apparatus of the present invention taken along lines  4 - 4  of  FIG. 2 ; 
         FIG. 5  is an elevation view of a preferred embodiment of the apparatus of the present invention taken along lines  5 - 5  of  FIG. 2 ; 
         FIG. 6  is a sectional view of a preferred embodiment of the apparatus of the present invention taken along lines  6 - 6  of  FIG. 2 ; 
         FIG. 7  is a fragmentary view of a preferred embodiment of the apparatus of the present invention showing elevating safety support; 
         FIG. 8  is a perspective view of a preferred embodiment of the apparatus of the present invention; 
         FIG. 9  is a fragmentary view of a preferred embodiment of the apparatus of the present invention taken along lines  9 - 9  of  FIG. 2  and showing the fork tube sections and torque tube; 
         FIG. 10  is a fragmentary view of a preferred embodiment of the apparatus of the present invention showing perimeter beam detail; 
         FIG. 11  is a fragmentary view of a preferred embodiment of the apparatus of the present invention taken along lines  11 - 11  of  FIG. 2  showing perimeter beam detail; 
         FIG. 12  is a fragmentary view of a preferred embodiment of the apparatus of the present invention showing fork tube section; 
         FIG. 13  is a fragmentary view of a preferred embodiment of the apparatus of the present invention taken along lines  13 - 13  of  FIG. 2  showing fork tube section; 
         FIGS. 14-15  are fragmentary views of a preferred embodiment of the apparatus of the present invention showing corner details; and 
         FIGS. 16-18  are fragmentary views of a preferred embodiment of the apparatus of the present invention that illustrate the gate latches. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIGS. 1-18  show a preferred embodiment of the present invention designated generally by the numeral  10 . Transportable rack apparatus  10  is designed to hold a pair of tank modules upon floor or platform  12 , one tank module in each of the two floor segments  19 ,  20 . Apparatus  10  can be of welded and bolted structural steel construction. 
     Rack apparatus  10  has a base or substructure  11  that can be of welded beams and plate steel or other suitable structural material. Base or substructure  11  has sockets or tubes  31 ,  32  which are receptive of the tines of a forklift, thus enabling the apparatus  10  to be lifted and transported with such a forklift. In  FIGS. 9 and 12-13 , a torque tube  73  is positioned in between sockets  31 ,  32 .  FIGS. 10-11  show perimeter or rim beam or beams  72  attached to and extending down from floor  12 . Gussets  74  are attached to torque tube  73 . Fork tube bottom plates  75  abut gussets  74 . Fork tube side plates  76  have an ell shape with the lower part of the plate  76  angled (see angle  78 ,  FIGS. 9 and 12 ) to load plate  75  against gusset  74  (see arrows  88 ). Bolted connections  77  can attach each bottom plate  75  to a side plate  76 . Plate  76  can be welded at its upper end portion to the underside of floor  12 . Torque tube  73  can be welded to the underside of floor  12 . Spacer or plate  79  is in between floor  12  and socket  31 ,  32 . 
     Sides  13 ,  14  extend upwardly from base  11 . Base  11  has ends  15 ,  16 , each provided with a door. The end  15 , has door  17 . The end  16  has door  18 . Each door  17 ,  18  pivots between open and closed positions (see arrows  53 ,  FIG. 2 ). Gate  18  pivots on hinges  65  that are attached (e.g., welded) to support  27 . Gate  17  pivots on hinges  66  that are attached (e.g., welded) to support  25  (see  FIGS. 3-4 ). Gate latches  58  are provided for enabling each door  17  or  18  to be locked or latched in a closed position as shown in hard lines in  FIGS. 1-5, 8, and 16-18 . In  FIGS. 16-18 , each latch  58  includes a vertical rod  83  mounted in bearings  84 . When rod  83  enters locking tube  85 , the latch  58  is locked. When rod  83  is removed from locking tube  85 , latch  58  is unlocked so that door  17  or  18  can be opened. In  FIG. 16 , rods  83  are in the unlocked position. In  FIG. 17 , rods  83  are in the locked position. Arrows  87  show movement to the locked position. Bearings  84  can be supported by vertical beam  86 . Each side  13 ,  14  has an upper horizontal beams, lower horizontal beams and diagonal beams. In  FIG. 1 , side  13  had upper horizontal beams  33 ,  34  and lower horizontal beams  35 ,  36 . Each horizontal beam  33 ,  34 ,  35 ,  36  spans from a corner column  21  or  24  to an intermediate column  29 . Diagonal beams  41 ,  42  are provided as seen in  FIG. 1 . Each diagonal beam  41 ,  42  extends from a corner column  21  or  24  to connect with a plate  45  or  46 . Each diagonal beam  41  or  42  is connected (e.g., welded) to an upper horizontal beam  33  or  34  and to a lower horizontal beam  35  or  36  as seen in  FIG. 1 . Similarly or identically constructed to side  13 , side  14  would have upper horizontal beams  37 ,  38  and lower horizontal beams  39 ,  40  as well as diagonal beams  43 ,  44  (see  FIG. 5 ). 
     The rack apparatus  10  of the present invention is of an improved construction that is very rugged for use in hostile marine and offshore environments and when supporting heavy leads such as liquid filled tanks or vessels. Corner columns  21 ,  22 ,  23 ,  24  extend upwardly from each corner of base  11 . Each corner column  21 - 24  is fitted with a lifting eye  55  as shown in the detail of  FIGS. 1-5, 8, 16-17 . The lifting eye  55  can be fitted with couplers such as shackles and slings in order to effect a lift of the combination of rack apparatus  10  and contained tank modules. 
     Each corner column  21 ,  22 ,  23 ,  24  is reinforced with a vertical support  25 ,  26 ,  27  or  28 . Plates  54  or hinges  65 ,  66  span between each corner column  21 - 24  and its vertical support  25 - 28 . One or more plates  54  can be used to form a connection between each corner column  21 ,  22 ,  23  or  24  and its vertical support  25 ,  26 ,  27 ,  28 . 
     A pair of intermediate columns  29 ,  30  are provided, each being about midway between ends  15 ,  16  (see  FIGS. 1-2 and 5-8 ). Reinforcements connect between each corner column  21 ,  22 ,  23 ,  24  and an intermediate column  29  or  30 . These reinforcements include upper horizontal beams  33 ,  34 ,  37 ,  38 . Diagonal beams  41 ,  42 ,  43 ,  44  are provided. Each diagonal beam  41 - 44  extends from a position at the upper end of a corner column  21 - 24  to a plate  45 ,  46 ,  47 ,  48  (see  FIGS. 1 and 5 ). 
     Each plate  45 ,  46 ,  47 ,  48  preferably provides a vertical section  49 , horizontal section  50 , diagonal section  51  and an opening  52 . The vertical section  49  of each plate  45 - 48  attaches (e.g., welded) to base  11 . The horizontal section  50  of each plate  45 ,  46 ,  47 ,  48  attaches to an intermediate column  29 ,  30 . A diagonal section  51  of plate  45 ,  46 ,  47 ,  48  attaches to the lower end portion of a diagonal beam  41 - 44  as can be seen in  FIGS. 1 and 5 . 
     Each lifting eye  55  is attached to a corner column  21 ,  22 ,  23 ,  24 . In  FIGS. 1 and 5 , corner column  21 ,  22 ,  23 ,  24  provides a lifting eye  55 . Also seen in  FIGS. 1 and 5  are the vertical supports  25 - 28  that reinforce the corner columns  21 - 24 . Also seen in  FIG. 5  are plate sections  54  that are welded to both intermediate column  23  and vertical support  27 . Hinge pin  56  (see  FIG. 3 ) extends between the horizontal hinge plate  57  of hinges  65  or  66  and provides a location for attachment of a door  17  or  18 . 
     Fall arrest pole  59  (see  FIGS. 6-7 ) telescopes inside of intermediate column  29 . Pole  59  can provide eyelet  60  that accepts linkage for connecting a workers safety harness to pole  59  when pole  59  is extended (see arrow  80 ,  FIG. 7 ). Pole  59  can be locked in the elevated position  61  of  FIG. 7 . 
     Diagonally extending plates  81 ,  82  extend downwardly from corner column  21 - 24  just below lifting eye  55 . Plate  81  connects with the top of a vertical support  25 - 28 . Plate  82  connects (welded) to an upper horizontal beam  33 ,  34 ,  37 ,  38 . The plates  81 ,  82  prevent lift lines from tangling with the upper end portion of corner column  21 - 24 , plates  54  and/or upper horizontal beam  33 ,  34 , or  37 ,  38 . 
     In  FIGS. 2 and 6 , middle wall  62  provides upper horizontal support  63  that spans between intermediate columns  29 ,  30 . Diagonal support  64  extends from an upper end portion of intermediate column  30  to a lower end portion of column  29  as seen in  FIG. 6 . 
     Floor  12  can have a grade or slant  67  to channel any spills to drain  68  (see  FIGS. 1-3 and 6 ). Drain  68  connects to flow line  69  which has valve  70 . Opening  71  in base  11  allows access to valve  70 . 
     The following is a list of suitable parts and materials for the various elements of a preferred embodiment of the present invention. 
     
       
         
           
               
            
               
                   
               
               
                 PARTS LIST 
               
            
           
           
               
               
            
               
                 PART NO. 
                 DESCRIPTION 
               
               
                   
               
               
                 10 
                 transportable rack apparatus 
               
               
                 11 
                 base/substructure 
               
               
                 12 
                 platform/floor 
               
               
                 13 
                 side 
               
               
                 14 
                 side 
               
               
                 15 
                 end 
               
               
                 16 
                 end 
               
               
                 17 
                 door 
               
               
                 18 
                 door 
               
               
                 19 
                 floor segment 
               
               
                 20 
                 floor segment 
               
               
                 21 
                 corner column 
               
               
                 22 
                 corner column 
               
               
                 23 
                 corner column 
               
               
                 24 
                 corner column 
               
               
                 25 
                 vertical support 
               
               
                 26 
                 vertical support 
               
               
                 27 
                 vertical support 
               
               
                 28 
                 vertical support 
               
               
                 29 
                 intermediate column 
               
               
                 30 
                 intermediate column 
               
               
                 31 
                 socket/tube 
               
               
                 32 
                 socket/tube 
               
               
                 33 
                 upper horizontal beam 
               
               
                 34 
                 upper horizontal beam 
               
               
                 35 
                 lower horizontal beam 
               
               
                 36 
                 lower horizontal beam 
               
               
                 37 
                 upper horizontal beam 
               
               
                 38 
                 upper horizontal beam 
               
               
                 39 
                 lower horizontal beam 
               
               
                 40 
                 lower horizontal beam 
               
               
                 41 
                 diagonal beam 
               
               
                 42 
                 diagonal beam 
               
               
                 43 
                 diagonal beam 
               
               
                 44 
                 diagonal beam 
               
               
                 45 
                 plate 
               
               
                 46 
                 plate 
               
               
                 47 
                 plate 
               
               
                 48 
                 plate 
               
               
                 49 
                 vertical section 
               
               
                 50 
                 horizontal section 
               
               
                 51 
                 diagonal section 
               
               
                 52 
                 opening 
               
               
                 53 
                 arrow 
               
               
                 54 
                 plate 
               
               
                 55 
                 lifting eye 
               
               
                 56 
                 hinge pin 
               
               
                 57 
                 hinge plate 
               
               
                 58 
                 gate latch 
               
               
                 59 
                 fall arrest pole 
               
               
                 60 
                 eyelet 
               
               
                 61 
                 elevated position 
               
               
                 62 
                 middle wall 
               
               
                 63 
                 upper horizontal support 
               
               
                 64 
                 diagonal support 
               
               
                 65 
                 hinge 
               
               
                 66 
                 hinge 
               
               
                 67 
                 slant/grade 
               
               
                 68 
                 drain 
               
               
                 69 
                 flow line 
               
               
                 70 
                 valve 
               
               
                 71 
                 opening 
               
               
                 72 
                 rim beam/perimeter beam 
               
               
                 73 
                 torque tube 
               
               
                 74 
                 gusset 
               
               
                 75 
                 fork tube bottom plate 
               
               
                 76 
                 fork tube side plate 
               
               
                 77 
                 bolted connection 
               
               
                 78 
                 angle 
               
               
                 79 
                 plate 
               
               
                 80 
                 arrow 
               
               
                 81 
                 plate 
               
               
                 82 
                 plate 
               
               
                 83 
                 rod 
               
               
                 84 
                 bearing 
               
               
                 85 
                 locking tube 
               
               
                 86 
                 vertical beam 
               
               
                 87 
                 arrow 
               
               
                 88 
                 arrow 
               
               
                   
               
            
           
         
       
     
     All measurements disclosed herein are at standard temperature and pressure, at sea level on Earth, unless indicated otherwise. 
     The foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims.