Patent ID: 6132009
Filing Date: 2000-10-17
Classification: B60T

Abstract:
A valve system for exhausting air from a brakepipe in a remote portion of a train, said valve system comprising:(a) a pressure containment structure including a housing and a housing cover, said housing having a cylindrical outer bore formed therein;(b) a piston mounted for axial motion in said cylindrical outer bore;(c) a first valve chamber formed within said pressure containment structure, said first valve chamber being covered by said housing cover and being disposed on a first side of said piston;(d) a second valve chamber formed within said housing portion of said pressure containment structure, said second valve chamber being disposed on a second side of said piston;(e) a diaphragm connected to said piston and to said pressure containment structure, said diaphragm providing a seal between said piston and said cylindrical outer bore to provide a pressure boundary between said first valve chamber and said second valve chamber, said diaphragm having an annular fold for permitting relative axial movement of said piston within said cylindrical outer bore, said annular fold being directed away from said first valve chamber and toward said second valve chamber;(f) a brakepipe pressure connection formed within said pressure containment structure, said brakepipe pressure connection for connection to such brakepipe;(g) a first brakepipe pressure passageway formed within said pressure containment structure, said first brakepipe pressure passageway for conveying brakepipe pressure from said brakepipe pressure connection to said first valve chamber;(h) a control pressure connection formed within said pressure containment structure for connection to a control chamber;(i) a control pressure passageway formed within said pressure containment structure, said control pressure passageway joining said control pressure connection to said second valve chamber for conveying a control pressure in such control chamber to said second valve chamber;(j) a biasing means connected to said piston and to said pressure containment structure for urging said piston to move toward said first valve chamber;(k) a stem connected at a first end thereof to said piston;(l) a brakepipe exhaust valve having a moveable portion connected to an axially opposed second end of said stem to be activated thereby, said brakepipe exhaust valve being closed when said piston is moved toward said first valve chamber and being opened when said piston is moved toward said second valve chamber;(m) an exhaust chamber disposed within said pressure containment structure on a first side of said brakepipe exhaust valve, said exhaust chamber being connected to atmosphere;(n) a brakepipe pressure chamber formed within said pressure containment structure on a second side of said brakepipe exhaust valve;(o) a second brakepipe pressure passageway formed within said pressure containment structure, said second brakepipe pressure passageway connected to said brakepipe pressure connection and to said brakepipe pressure chamber so that when such control chamber is supplied with air at brakepipe pressure said brakepipe exhaust valve is closed and so that when a control pressure in such control chamber is reduced by venting to atmosphere said brakepipe exhaust valve is opened to exhaust brakepipe air from said brakepipe pressure connection through said second brakepipe passageway to said exhaust chamber and thence to atmosphere; and(p) an annular sleeve included as a portion of said housing cover, said annular sleeve protruding into said fold of said diaphragm to prevent said diaphragm from inverting if said brakepipe pressure drops below such pressure in such control chamber when said piston is positioned toward said first valve chamber.