Patent ID: 6047839
Filing Date: 2000-04-11
Classification: B61G,F16F

Abstract:
A rail car buffer comprising:a capsule body including a tubular base having a body plate at one end of the buffer and a tubular plunger having a contact head at the other end of the buffer, said base and plunger being fitted together to define a generally cylindrical interior chamber between the body plate and head;a hydraulic spring in said interior chamber extending between said plate and said contact head, said hydraulic spring including a housing at one end of said interior chamber with opposed front and rear heads and a pressure cylinder extending between and joining the heads, a fluid displacement piston in the pressure cylinder engaging the interior surface of said pressure cylinder, a piston rod extending from said piston sealingly through said front head to a free end at the other end of said interior chamber, a rod plate on the free end of the piston, the rod plate abutting one of said body plate and said contact head, the rear head abutting the other of said body plate and contact head, a cylindrical outer body extending between and joining said front and rear heads and spaced outwardly from the pressure cylinder, said pressure cylinder, outer body, front head and rear head defining an annular reservoir located between said pressure cylinder and outer body, flow control apertures in the pressure cylinder, hydraulic fluid in the housing, said hydraulic fluid entirely filling the pressure cylinder and partially filling the reservoir, a gas pocket at the top of the reservoir above the said pocket located above the interior of the pressure cylinder; anda cylindrical mechanical spring in said interior chamber arranged in parallel with said hydraulic spring and having opposed spring ends, said mechanical spring surrounding the hydraulic spring and extending along the length of the interior chamber with one mechanical spring end abutting the rod plate, the other mechanical spring end abutting the hydraulic spring housing at said other end, and surrounding both the hydraulic spring housing and the hydraulic reservoir.