Abstract: The method and system for attenuating or damping the amplitude of vacuum pressure oscillations in a vacuum system uses a flow-modulated damper to disperse and damp high-amplitude vacuum oscillations of a vacuum generator to a degree where fine vacuum control may be achieved for delicate work such as eye surgery.

Abstract: A retarder control valve assembly and system for controlling speed of rail cars, utilizes cartridge valves carried in a manifold body including piping and pilot control apparatus, but no wearing surfaces, dynamic seals, or moving parts. The cartridge valves are replaceable without replumbing, and include all moving valve elements and dynamic seals. The valves each include a piston controlled poppet carried on a spool movable within a cartridge body to open and close the valve and supported to withstand high side loads. The pressure sensing and feedback to the retarder system controller is at the manifold, in a pressure spike attenuating circuit having a phase modulating capability to mimic retarder pressure remotely.

Abstract: A retarder control valve assembly and system for controlling speed of rail cars, utilizes cartridge valves carried in a manifold body including piping and pilot control apparatus, but no wearing surfaces, dynamic seals, or moving parts. The cartridge valves are replaceable without replumbing, and include all moving valve elements and dynamic seals. The valves each include a piston controlled poppet carried on a spool movable within a cartridge body to open and close the valve and supported to withstand high side loads. The pressure sensing and feedback to the retarder system controller is at the manifold, in a pressure spike attenuating circuit having a phase modulating capability to mimic retarder pressure remotely.

Abstract: The method and system for attenuating or damping the amplitude of vacuum pressure oscillations in a vacuum system uses a flow-modulated damper to disperse and damp high-amplitude vacuum oscillations of a vacuum generator to a degree where fine vacuum control may be achieved for delicate work such as eye surgery.