Abstract: An end-of-car coupler includes a hydro-pneumatic cushioning device. The latter has a ported tube separating the hydraulic cylinder chamber from an outer annular chamber containing gas. Each port is fitted with a valve, the obturating member of each valve being a differential area piston. The valves are all closed until subjected to a certain threshold force by movement of the plunger in the cylinder when all those valves between the plunger and the end of the cylinder chamber open to allow liquid flow between the two chambers.

Abstract: A buffer comprising a plunger slidable in a ported tube. A metal tubular member circumferentially surrounds that part of the ported tube in which all the flow resisting ports are formed and is the radially inner wall of an annular space filled with compressed gas. The outer wall of an annular space is formed by a tubular membrane. The annular chamber between the ported tube and the metal tubular member is part of a low pressure reservoir of the buffer and communicates via an annular passage in the closed end of the buffer with the remainder of the reservoir which is an annular chamber formed between the tubular membrane and the outer tubular wall of the buffer. The metal tubular member shields the tubular membrane from the damaging effects of jets of liquid forced through the flow resisting ports during compression of the buffer.

Abstract: A railroad vehicle end-of-car center coupler includes a telescopic energy absorber comprising a hollow cylindrical plunger in a cylinder having one closed end. The plunger has an aperture in its inner end wall. A perforated metering tube is fixed in the closed end wall by a special fixing arrangement. It projects through the aperture and carries an annular piston head which slides in the bore of the plunger. A floating piston divides the interior of the plunger into a gas space and a liquid chamber. Four direct acting pressure relief valves are mounted in the piston head. Conduits through the tube connect their inlets to respective ones of four axially-spaced ports in the outer surface of the tube so that they all communicate with the annular chamber that surrounds the tube within the plunger when the absorber is compressed and so that they are progressively cut-off from such communication during the final stages of extension of the absorber.

Abstract: Movable buffer stop apparatus (10) for a railway vehicle comprises a stop plate (27) on an arm (21), and a support strut (31) movable angularly relative to the arm (21) by an hydraulic cylinder (33) between raised and lowered conditions of the apparatus (10). The arm (21) and the support strut (31) are mounted on a truck (14) which cooperates with a fixed energy absorbing buffer (35) in a sunken pit (11).

Abstract: A liquid damper comprises a piston head which slides within a cylinder and which is carried by a piston rod which slides within an annular gland at one end of the cylinder. A passage which includes a damping valve connects the annular cylinder space to a liquid reservoir so that liquid displaced from the annular cylinder space by movement of the piston in either direction is fed through the damping valve to the liquid reservoir. The liquid reservoir is connected to the other cylinder space through a non-return valve. A groove which varies in area along its length, extends partway along the piston rod.