Abstract: A fabricated backstop for an end-of car cushioning unit in a railway car. The backstop is composed of two plate members or pieces which are welded separately to the inside of a center sill. One backstop piece is a generally U-shaped vertical plate member which is welded about its entire outer circumference to the inside of the center sill and provides an over-solid stop. The second backstop piece is a horizontal plate member positioned in contact with the rear face of the vertical plate member and having a cutout portion to receive an end collar of an end-of-car cushioning device. The horizontal plate member is welded at its front face to the vertical plate member and at its outer sides to the center sill to provide a rear buff stop and a rear draft stop.

Abstract: An end-of-car railway car cushioning unit has a cylinder and a cylindrical piston mounted in the cylinder with the piston rod secured to the piston extending through an opening in the rear end of the cylinder with the piston forming a high pressure fluid chamber on the front face thereof and a low pressure fluid chamber on the rear face thereof. The piston has a plurality of openings therethrough and a metering valve is mounted in each of the openings to meter fluid flow between the low pressure chamber and the high pressure chamber. Each metering valve has a buff flow passage and a restricted draft flow passage. At least one selected metering valve has a cylindrical extension thereon projecting from the front face of the piston and adapted to engage an end wall of the high pressure chamber as the piston approaches the end of its buff stroke to block the flow of fluid from the high pressure chamber to the associated metering valve adjacent the end of the buff stroke.

Abstract: An end-of-car hydraulic pneumatic cushioning device for connecting to the coupler of a railway car having a piston mounted within a cylinder and a piston rod secured to the piston extending rearwardly from the cylinder. The piston divides the cylinder into a front high pressure chamber and a rear low pressure chamber, and a gaseous and liquid fluid mixture is provided in both the high and low pressure chambers. The piston carries normally closed metering valves which open in buff travel a buff flow passage between the low and high pressure chambers after around two inches or more of buff travel from neutral extended position, and open upon return draft travel after buff travel a restricted draft flow passage between the low and high pressure chambers. The gas in the fluid mixture particularly upon high velocity impact loads is dispersed throughout the liquid and thus has a large contact area with the liquid to minimize the increase in temperature of the gas upon being compressed.