Oil-free air compressor for rail vehicles with air ventilation

Abstract

An oil-free compressor for a rail vehicle includes a multi-piece compressor housing, a first piston cylinder supported in a first opening in the compressor housing, a second piston cylinder supported in a second opening in the compressor housing, a multi-piece crankshaft assembly supported by the compressor housing, and an optionally filtering air plenum in fluid communication with the compressor housing interior to provide a volume of air to the compressor housing interior. The crankshaft assembly is linked to pistons of the first and second piston cylinders by respective connecting rods. The connecting rods connect to a wrist pin associated with each of the pistons, and the wrist pins are respectively supported by a dry lubricant bushing to the associated piston. The compressor housing may have a first housing portion and a second housing portion forming respective halves of the compressor housing.

The invention claimed is: 
     
         1 . An oil-free compressor for a rail vehicle, comprising:
 a compressor housing comprising at least a first housing portion and a second housing portion to define a compressor housing interior;   a first piston cylinder supported in a first opening in the compressor housing;   a second piston cylinder supported in a second opening in the compressor housing and fluidly connected to the first piston cylinder;   a multi-piece crankshaft assembly supported by the compressor housing and linked to the pistons of the first and second piston cylinders by respective connecting rods; and   an air plenum in fluid communication with the compressor housing interior to provide a volume of air to the compressor housing interior.   
     
     
         2 . An oil-free compressor as claimed in  claim 1 , wherein the first housing portion and the second housing portion form respective halves of the compressor housing and are secured together with mechanical fasteners. 
     
     
         3 . An oil-free compressor as claimed in  claim 1 , wherein the first piston cylinder is larger than the second piston cylinder. 
     
     
         4 . An oil-free compressor as claimed in  claim 1 , wherein the crankshaft assembly comprises a crankshaft center section and two end sections. 
     
     
         5 . An oil-free compressor as claimed in  claim 4 , wherein the end sections contain counterweights. 
     
     
         6 . An oil-free compressor as claimed in  claim 4 , wherein opposing ends of the crankshaft center section are secured within respective cavities in the end sections. 
     
     
         7 . An oil-free compressor as claimed in  claim 1 , wherein the air plenum is in fluid communication with the first piston cylinder. 
     
     
         8 . An oil-free compressor as claimed in  claim 1 , further comprising an air intake valve in the compressor housing enabling air to be drawn into the compressor housing interior from the air plenum. 
     
     
         9 . An oil-free compressor as claimed in  claim 8 , further comprising an air discharge valve in the compressor housing enabling air to be discharged from the compressor housing interior. 
     
     
         10 . An oil-free compressor for a rail vehicle, comprising:
 a multi-piece compressor housing;   a first piston cylinder supported in a first opening in the compressor housing;   a second piston cylinder supported in a second opening in the compressor housing and fluidly connected to the first piston cylinder;   a multi-piece crankshaft assembly supported by the compressor housing and linked to pistons of the first and second piston cylinders by respective connecting rods, wherein the connecting rods connect to a wrist pin associated with each of the pistons, and the wrist pins are respectively supported by a dry lubricant bushing to the associated piston; and   an air plenum in fluid communication with the compressor housing interior to provide a volume of air to the compressor housing interior.   
     
     
         11 . An oil-free compressor as claimed in  claim 10 , wherein the compressor housing comprises at least a first housing portion and a second housing portion. 
     
     
         12 . An oil-free compressor as claimed in  claim 11 , wherein the first housing portion and the second housing portion form respective halves of the compressor housing and are secured together with mechanical fasteners. 
     
     
         13 . An oil-free compressor as claimed in  claim 10 , wherein the first piston cylinder is larger than the second piston cylinder. 
     
     
         14 . An oil-free compressor as claimed in  claim 10 , wherein the crankshaft assembly comprises a crankshaft center section and two end sections. 
     
     
         15 . An oil-free compressor as claimed in  claim 14 , wherein the end sections contain counterweights. 
     
     
         16 . An oil-free compressor as claimed in  claim 14 , wherein opposing ends of the crankshaft center section are secured within respective cavities in the end sections. 
     
     
         17 . An oil-free compressor as claimed in  claim 10 , wherein the air plenum is in fluid communication with the first piston cylinder. 
     
     
         18 . An oil-free compressor as claimed in  claim 10 , further comprising an air intake valve in the compressor housing enabling air to be drawn into the compressor housing interior from the air plenum. 
     
     
         19 . An oil-free compressor as claimed in  claim 18 , further comprising an air discharge valve in the compressor housing enabling air to be discharged from the compressor housing interior. 
     
     
         20 . An oil-free compressor as claimed in  claim 10 , wherein the dry lubricant bushing comprises a PEAK liner.