Railcar cushion unit

Abstract

A railway car cushioning device is provided for minimizing slack between railway cars. The cushioning device is provided with a piston and piston rod disposed within the cylinder. The cylinder is filled with an oil and gas mixture. A housing surrounds the cylinder providing a fluid recovery reservoir defined by the space between the outer wall of the cylinder and the housing. At one end of the cylinder is a bulkhead and at the other end is a cylinder head. The piston rod extends through a hole formed in the cylinder head and is joined to the sill of a railcar. A coupler is joined to the cushioning device for coupling to another railway car. A series of pressure relief valves are provided and engaged with egress ports formed in the cylinder wall between the bulk head and the piston when the piston is in an extended position. The pressure relief valves are constructed so that fluid may flow in only one direction, from the interior of the cylinder to the fluid reservoir. The pressure relief valves open only in response to a given fluid pressure within the cylinder. A restoration valve allows fluid to escape from the cylinder when the piston is restored to its initial position, and a bleed valve is provided for exhausting gas from the cylinder when the cushioning device is at rest.