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. Heat generated by forcing the liquid through the flow resisting ports is carried by liquid flow from the radially inner annular chamber to the radially outer annular chamber via the annular passage and is dissipated from the radially outer annular chamber through the external tubular wall of the buffer.
A rail car buffer with a capsule body and a mechanical ring spring and a hydraulic spring arranged in parallel in the body. The hydraulic spring includes an internal reservoir to receive hydraulic oil displaced during collapse of the buffer.
A rail car buffer includes a standard capsule body and a high pressure hydraulic buffer spring only in the body. The hydraulic spring has a high compression ratio and is charged with very high pressure gas and hydraulic oil.
A rail car buffer has a capsule body and a spring assembly with an elastomer spring and a gas filled hydraulic spring in the body. Expansion of the buffer after collapse is snubbed by the gas filled hydraulic spring to convert energy stored in the elastomer spring to heat.
