LADING PROTECTION DEVICE

摘要

A lading protection device in the form of a shock absorber for a railway car including a cylinder containing a piston and a body of hydraulic fluid normally captive between the front face of the piston and the closed end of the cylinder. A flow control valve assembly, centered in the piston, mounts an orifice bushing defining a constricted circular orifice. The assembly includes a valve stem slidable in the piston with a spring at its inner end for pressing the stem in a direction to seal the orifice. The piston has a fluid passage extending therethrough and an annular separator piston defines, with the main piston, a receiving space into which the fluid flows upon impact. The space in back of the separator piston is filled with a charge of gas under high pressure so that when the impact has been dissipated the gas pressure acting upon the separator piston restores the fluid to its normal position in readiness for a succeeding impact. The invention also resides in the structure of the orifice bushing and a system of seals and lubrication which minimizes leakage over a long period of time. 16-116/jcp p