Abstract: A brake valve assembly suitable for use in a railway air brake system to control flow of air between the on-board reservoir and a respective brake cylinder. The valve assembly may include a plurality of internal valves to permit three states of fluid transfer, i.e., delivery, exhaust and lap. The internal valves are controlled by respective solenoids that act directly on the valve element. Internal forces due to fluid pressure are balanced using counterbalance assemblies preferably including a flexible, rolling diaphragm disposed adjacent to a configured follower member. The counterbalance assemblies maintain substantial balance throughout the reciprocative stroke of the valve element.

Abstract: A solenoid-operated fluid control valve having manual override and fluid latching for establishing a fluid path between a supply port and a delivery port when a brake-release solenoid pilot valve coil is momentarily energized to cause a pilot piston to close an exhaust valve and to open a supply valve for causing feedback pressure to be fed from a delivery chamber to a pilot chamber for fluid latching the pilot piston in a brake-release position until a brake-application solenoid pilot valve coil is momentarily energized which causes the pilot chamber to exhaust to atmosphere so that the pilot piston returns and opens the exhaust valve and allows the closure of the supply valve.

Abstract: A fluid pressure switch includes a housing with a cylindrical bore, a spring housing bore and a guide bore between the cylindrical bore and the spring housing bore. A shaft member axially disposed in the housing between the bore, has a piston element secured on the end within the cylindrical bore for movement in one direction or another upon a differential between fluid pressure sources as presented to the two opposing surfaces of the piston element. A spring-biasing arrangement is secured to the shaft member on the end within the spring housing bore for opposing movement of the shaft member. The spring-biasing arrangement is adjustable both as to the spring force and as to the spring stop setting. A switch operator member secured to the piston member, spreads contact arms apart upon a predetermined displacement of the piston. The switch operator member has an elliptically-shaped eccentric portion which can be rotated to adjust the point of shaft displacement at which switch operation occurs.

Abstract: An improved mechanical arrangement is disclosed for removably attaching a circuit board to a mounting box. An edge portion of the circuit board containing the board's heat conductive strip slides between two elongated heat sink guides attached to the mounting box, the edge portion containing a vertical cam shaft with an eccentric cam exerts pressure upon one of the heat sink guides in response to a rotation of the cam shaft by an attached lever-type handle. Since the cam shaft is attached by support members to the circuit board, the shaft acts as a beam spring so as to force the heat conductive strip against the second of the heat sink guides.