Westinghouse Air Brake Company

Robert G Bostedo

Daniel G Scott

Robert D Dimsa

Gregory L Johnston

Ralph Santoro, Jr

Brian L Cunkelman

A purge valve for expelling liquid contaminants from a fluid conduit which is normally unpressurized but is at times pressurized with a gas which contains liquid contaminants. It has a housing, a diaphragm mounted within the housing, a control chamber on a first side of the diaphragm, an exhaust passage on a second side of the diaphragm and a valve seat surrounding the exhaust passage. The valve seat is positioned so that the diaphragm can seal against it. A spring on the second side of the diaphragm presses it away from the seat. An annular chamber is on the second side of the diaphragm, surrounding the exhaust passage. The annular chamber is open to the exhaust passage when the diaphragm is unseated from the valve seat. The valve has a low impedance flow path between the control chamber and the fluid conduit. The valve also has a high impedance discharge flow path connected to the annular chamber. The high impedance discharge flow path may be connected to the control chamber, connected to the low impedance flow path, or it may be for connection to the fluid conduit. When the valve is connected to the fluid conduit, it is open due to the spring force whenever the fluid conduit is unpressurized so that the liquid contaminant may drain from the valve. When the fluid conduit is pressurized, the diaphragm is pressed against the valve seat so that the valve is closed.

Normally open purge valve

An aftercooler for cooling a compressed fluid exiting from a compressor, the aftercooler including a radiator unit for receiving the compressed fluid exiting from the compressor and for cooling the compressed fluid, the radiator unit having an inlet for receiving the compressed fluid, an outlet for discharging the compressed fluid and a plurality of heat exchange passageways connecting the inlet and the outlet for transferring heat from the compressed fluid. The aftercooler also includes a bypass channel for bypassing the plurality of heat exchange passageways which extends from a first point substantially adjacent the inlet of the radiator unit to a second point substantially adjacent the outlet of the radiator unit. The aftercooler also includes a bypass flow proportioning mechanism that is effective to proportion the flow of the compressed fluid exiting from the compressor and flowing through the aftercooler between the radiator unit and the bypass channel dependent upon a pressure differential across the radiator unit. Preferably, the bypass flow proportioning mechanism is a substantial restriction disposed along the bypass channel which operates to continuously proportion flow between the radiator unit and the bypass channel. The bypass channel is formed substantially integrally with the radiator unit. Preferably, the plurality of heat exchange passageways are arranged to form an array and at least a portion of a length of the bypass channel extends contiguous with a portion of a periphery of the array of the heat exchange passageways.

Aftercooler having bypass passage integrally formed therewith

The invention is a valve for expelling a liquid contaminant from a gas in a conduit. It is used for a conduit with a pressure subject to variations in time. The valve has a housing containing a diaphragm with a control chamber on one side of the diaphragm and an exhaust passage on the other side. A valve seat surrounds the exhaust passage. A spring presses the diaphragm against the valve seat so that the valve is normally closed and an annular chamber surrounds the exhaust passage. A low impedance discharge passage is connected to the annular chamber and to the conduit. A high impedance control passage is connected to the control chamber and is either connected to the discharge passage or to the conduit. When the conduit pressure remains constant in time, the pressure in the control chamber equilibrates with it so that a net pressure force on the diaphragm plus the spring force presses the diaphragm against the valve seat so that the valve is closed. When the conduit pressure is zero, the spring keeps the valve closed. When the pressure in the conduit increases rapidly, the pressure in the annular chamber rises faster than the pressure in the control chamber so that the net pressure force on the diaphragm becomes directed away from the valve seat and overcomes the spring force so that the diaphragm unseats and gas containing the contaminant liquid is purged from the valve.

Growing community of inventors

Pittsburgh, PA, United States of America

Robert G Bostedo