Tandem Carriage Railcar Indexer

Abstract

A railcar indexer system is disclosed that includes a design that enables extremely high loads to be moved without exceeding present railcar limitations. The railcar handling system of the present invention employs hydraulically-operated indexers that divide the load between consecutive dog carriages that, in turn, operate to apply force to railcar bogey frames or axles on consecutive railcars. This transfers a large amount of force to be applied to a lead railcar and enables a much larger amount of force to be applied to the next railcar and a larger total force to be applied to a string of railcars.

What is claimed is: 
     
         1 . A railcar handling system comprising:
 (a) an indexing unit including a pair of aligned sequentially positioned, hydraulically-operated dog carriages that carry railcar-engaging dogs and operate as lead and trailing dog carriages during a power stroke and are situated to address bogey frames or axles of consecutive railcar trucks of two connected railcars; and   (b) a hydraulic operating system for operating the dog carriages and associated dogs that functions in a manner such that force applied to the railcars is divided between the carriages enabling maximum allowable force to be applied to each of two consecutive connected railcars at the same time.   
     
     
         2 . A railcar handling system as in  claim 1  configured to address bogey frames further comprising a pair of coordinated units, one on either side of a railroad track thereby providing dogs that address both sides of consecutive bogey frames. 
     
     
         3 . A railcar handling system as in  claim 1  wherein the unit is disposed between the rails of a track and the dogs are designed to address axles of consecutive railcar trucks. 
     
     
         4 . A railcar handling system as in  claim 1  wherein the hydraulic operating system further comprises a plurality of consecutive, series-connected hydraulic cylinders, a final one of which is attached to a trailing dog carriage, at least one further series-connected tandem cylinder connected between the trailing dog carriage and the lead dog carriage that transfers and applies force to the lead dog carriage as a percentage of the force applied to the trailing dog carriage. 
     
     
         5 . A railcar handling system as in  claim 4  including a pair of spaced parallel tandem cylinders. 
     
     
         6 . A railcar handling system as in  claim 5  wherein the force applied to the lead dog carriage during a power stroke is one-half that applied by the trailing dog carriage. 
     
     
         7 . A railcar handling system as in  claim 1  wherein the carriage dogs are hydraulically raised against a downward bias. 
     
     
         8 . A railcar handling system as in  claim 1  wherein the direction of operation is reversible.