Plunger assembly for hydraulic cylinder

Abstract

A hydraulic cylinder includes piston and plunger assemblies fitted together with a retention ring. This design allows finish-machined pistons to be assembled without welding of semi-finished machine components.

What is claimed is:  
     
         1 . A plunger assembly for a hydraulic cylinder, said plunger assembly comprising: 
 a plunger tube;    a piston dimensioned to slide fit over said plunger tube; and    an inserted retention ring disposed about said plunger tube between said piston and said plunger tube;    wherein said piston is slid in position over said plunger tube, and wherein said inserted retention ring retains said piston and carries loads placed on said piston.    
     
     
         2 . The plunger assembly as claimed in  claim 1 , wherein said piston further comprises an end having a chamfer, and wherein said chamfer assists said piston to slide over said plunger tube.  
     
     
         3 . The plunger assembly as claimed in  claim 1 , wherein said piston further comprises an insertion slot disposed over said inserted retention ring, and wherein said inserted retention ring is disposed about said plunger tube by inserting said inserted retention ring into said insertion slot.  
     
     
         4 . The plunger assembly as claimed in  claim 1 , wherein said plunger tube further comprises an oil hole and an interior and exterior, and wherein said oil hole allows oil to pass from said exterior to said interior of said plunger tube.  
     
     
         5 . The plunger assembly as claimed in  claim 1 , wherein said piston comprises a machine finished piston.  
     
     
         6 . A plunger assembly for a hydraulic cylinder, said plunger assembly comprising: 
 a plunger tube;    a piston dimensioned to slide onto said plunger tube, said piston having an end with a chamfer, and a close fit about said plunger tube;    a retention ring disposed about said plunger tube between said piston and said plunger tube; and    an insertion slot in said piston disposed over said retention ring;    wherein said retention ring is disposed about said plunger tube by inserting said retention ring into said insertion slot, and wherein said chamfer assists said piston to slide over said plunger tube, and wherein said retention ring retains said piston about said plunger tube.    
     
     
         7 . The plunger assembly as claimed in  claim 6 , wherein said plunger tube further comprises an oil hole and an interior and exterior, and wherein said oil hole allows oil to pass from said exterior to said interior of said plunger tube.  
     
     
         8 . A telescoping hydraulic cylinder apparatus comprising: 
 a plurality of cylinders; and    a plunger assembly disposed inside each of said plurality of cylinders, said plunger assembly comprising: 
 a plunger tube;  
 a piston dimensioned to slide fit over said plunger tube;  
 a piston stop at an disposed at an end of said piston; and  
 an inserted retention ring disposed about said plunger tube between said piston and said plunger tube;  
   wherein said piston is slid into position over said plunger tube, and wherein said inserted retention ring retains said piston and carries loads placed on said piston, and wherein said piston stop receives said plunger assemblies from said plurality of cylinders when said telescoping hydraulic cylinder is closed.    
     
     
         9 . The telescoping hydraulic cylinder apparatus as claimed in  claim 8 , wherein said plunger assembly further comprises an insertion slot in said piston disposed over said inserted retention ring, and wherein said inserted retention ring is disposed about said plunger tube by inserting said inserted retention ring into said insertion slot.  
     
     
         10 . The telescoping hydraulic cylinder as claimed in  claim 9 , wherein said piston further comprises a wear guide groove, and wherein said wear guide groove accepts a wear ring to prevent scoring between each said plunger tube assembly.