Fork lift apparatus adapted to be coupled to a truck or trailer

Abstract

A fork lift with retractably extendable loading prongs for lifting loads from either side of a vehicle. The fork lift includes a mechanism for displacing the prongs over and across the vehicle, which mechanism has front and rear transverse girders which can be rigidly secured to the vehicle's chassis. The mechanism further includes front and rear masts, sprocketed wheels mounted on the masts to move the front and rear masts reciprocally, and a longitudinal beam which is coupled to the masts. The longitudinal beam can move up and down. Front and rear uprights extend downwardly from the longitudinal beam. The prongs are retractably engaged to the bottom of the uprights and are moved with hydraulic pistons.

1. A fork lift comprising retractably extendible loading prongs for lifting loads from either side of a vehicle, and a mechanism for displacing said prongs over and across said vehicle, said mechanism for displacing said prongs comprising:
 a front transverse girder and a rear transverse girder, said transverse girders adapted to be rigidly secured to a chassis of said vehicle;  
 a front mast and a rear mast, each of said masts extending generally horizontally  vertically and having a top and a bottom;  
 means for simultaneously reciprocating said front and rear masts at their bottoms along said front and rear girders, respectively;  
 a longitudinal beam coupled to said front and rear masts;  
 means for reciprocating said longitudinal beam in a downward-upward motion along said front and rear masts; and  
 a front upright and a rear upright, each of said uprights extending downward from said horizontal  longitudinal beam, wherein at least one of said retractable extendible prongs extends from each of said uprights.  
 
     
     
       2. A fork lift as in  claim 1 , wherein said prongs comprise front and rear transverse prongs retractably engaged to the bottoms of said front and rear uprights, correspondingly, and means for extending said front and rear transverse prongs from said front and rear uprights, correspondingly, toward either side of said vehicle. 
     
     
       3. A fork lift as in  claim 2 , wherein said beam comprises means for lowering or raising said front or rear uprights. 
     
     
       4. A fork lift as in  claim 2 , wherein said means for simultaneously reciprocating said front and rear masts along said front and rear girders, comprise sprocket wheels, wherein at least one sprocket wheel is mounted on each mast and is turned against mating toothed sprocket bars which are mounted on said front and rear girders, respectively. 
     
     
       5. A fork lift as  claim 4 , wherein said sprocket wheels are propelled by a hydraulic drive. 
     
     
       6. A fork lift as in  claim 2 , comprising a boom to which said front and rear masts are coupled to their tops. 
     
     
       7. A fork lift as in  claim 6 , wherein said means for reciprocating said longitudinal beam in a downward-upward motion comprises front and back hydraulic pistons mounted on said boom, wherein each piston is coupled to a chain which is connected to said beam, through a system of pulleys. 
     
     
       8. A fork lift as in  claim 2 , wherein said means for extending said front and rear transverse prongs from said front and rear uprights, comprises sprocket wheels, each having a hydraulic drive, wherein each sprocket wheel is mounted on each upright and is turned against mating toothed sprocket bars which are mounted on said front and rear transverse prongs. 
     
     
       9. A fork lift as in  claim 2 , wherein said beam comprises means for longitudinally moving said front or rear uprights along said beam. 
     
     
       10. A fork lift as in  claim 9 , wherein said means for longitudinally moving said front or rear uprights along said beam comprises hydraulic pistons. 
     
     
       11. A fork lift as in  claim 2 , wherein said prongs are pivotally mounted to the bottom of said uprights.  
     
     
       12. A fork lift as in  claim 11 , wherein said prongs are bar- shaped.    
     
     
       13. A fork lift as in  claim 11 , wherein said prongs are telescopic.  
     
     
       14. A fork lift as in  claim 11 , wherein said prongs are L- shaped.    
     
     
       15. A fork lift as in  claim 11 , wherein said prongs each comprise split prongs.  
     
     
       16. A fork lift as in  claim 15 , wherein each of said split prongs are for lifting two wheels of a car.  
     
     
       17. A fork lift as in  claim 2 , further comprising means for retaining a horizontal configuration of said prongs.  
     
     
       18. The fork lift of  claim 1 , wherein the load comprises another vehicle having wheels, and the fork lift lifts the vehicle by the wheels.  
     
     
       19. The fork lift of  claim 18 , wherein the fork lift lifts the another vehicle by the prongs engaging the wheels.  
     
     
       20. The fork lift of  claim 19 , wherein the prongs engage the wheels by translational motion of the front and rear uprights.  
     
     
       21. The fork lift of  claim 19 , wherein the prongs engage the wheels by angular motion of the front and rear uprights.  
     
     
       22. The fork lift of  claim 1 , the at least one of said retractable extendible prongs comprises a first prong arrangement and a second prong arrangement, the first prong arrangement extends from the front upright, the second prong arrangement extends from the rear upright.  
     
     
       23. The fork lift of  claim 22 , wherein the load comprises another vehicle having front wheels and rear wheels, the first prong arrangement has a first member that engages the front wheels at a first location and a second member that engages the front wheels at a second location, the second prong arrangement has a first member that engages the rear wheels at a first location and a second member that engages the rear wheels at a second location, and the fork lift lifts the another vehicle by the wheels.  
     
     
       24. The fork lift of  claim 23 , wherein the first member and the second member of the first prong are connected, and the first member and the second member of the second prong are connected.  
     
     
       25. The fork lift of  claim 23 ,
   wherein the means for simultaneously reciprocating said front and rear masts includes at least one of a hydraulic system and a cable system; and        wherein the means for reciprocating said longitudinal beam includes at least one of a hydraulic system and a cable system.      
     
     
       26. A fork lift comprising at least one retractably extendible loading prong for lifting a load from either side of a vehicle, and a mechanism which displaces said at least one prong over and across the vehicle, said mechanism comprising:
   a first transverse girder and a second transverse girder, said girders adapted to be secured to the vehicle;        a first mast and a second mast, each of said masts having a top and a bottom;        a first mechanism which simultaneously reciprocates said masts at their bottoms along said girders, respectively;        a beam coupled to said masts;        a second mechanism which reciprocates said beam along said masts; and        at least one member extending from said beam, wherein said at least one prong extends from said at least one member.      
     
     
       27. The fork lift of  claim 26 , wherein the load comprises another vehicle having wheels, and the fork lift lifts the vehicle by the wheels.  
     
     
       28. The fork lift of  claim 27 , wherein the fork lift lifts the another vehicle by the at least one prong engaging the wheels.  
     
     
       29. The fork lift of  claim 28 , wherein the at least one prong engages the wheels by translational motion of the at least one member.  
     
     
       30. The fork lift of  claim 28 , wherein the at least one prong engages the wheels by angular motion of the at least one member.  
     
     
       31. The fork lift of  claim 30 , the at least one member comprises a first member and a second member, the at least one prong comprises a first prong and a second prong, the first prong extends from the first member, the second prong extends from the second member, and the first and second prongs engage the wheels by angular motion of the first and second members.  
     
     
       32. The fork lift of  claim 26 , the at least one member comprises a first member and a second member, the at least one prong comprises a first prong having a first portion and a second portion, and a second prong having a first portion and a second portion, the first prong extends from the first member, the second prong extends from the second member.  
     
     
       33. The fork lift of  claim 32 , wherein the load comprises another vehicle having front wheels and rear wheels, the first portion of the first prong engages the front wheels at a first location, the second portion of the first prong engages the front wheels at a second location, the first portion of the second prong engages the rear wheels at a first location, the second portion of the second prong engages the rear wheels at a second location, and the fork lift lifts the another vehicle by the wheels.  
     
     
       34. The fork lift of  claim 32 , wherein the first portion and the second portion of the first prong are joined, and the first portion and the second portion of the second prong are joined.