An airflow control valve (20) for use in a breathing apparatus (10) to control a flow of air from a pressurized air supply to a respirator. The valve comprises an inlet port (31) for connection to a pressurized air supply, and first (32) and second (33) outlets. The valve is configurable between a first position in which the inlet port is in restricted fluid communication with the first outlet to allow a restricted flow of air from the inlet port to the first outlet and in which the second outlet is sealed from the inlet port and, a second position in which the inlet port is in substantially unrestricted fluid communication with the second outlet to allow an unrestricted flow of air from the inlet port to the second outlet.

The present invention relates to methods for operating and controlling flow control systems. The method includes sensing an actual medium flow through a pipe part and outputting an electrical signal indicative of the sensed actual medium flow; comparing the sensed medium flow with a set medium flow and outputting a control signal; using an orifice adjusting system to adjust an adjustable orifice in a pipe part in response to the control signal; and performing a correction of a characteristic curve. The method can include setting an upper limit for medium flow to V.sub.max wherein V.sub.max is less than a maximum medium flow.

A digital valve positioner for use with an actuator. The digital valve positioner includes a housing, at least one exhaust port opening formed in the housing, and a vent assembly operatively coupled to the at least one exhaust port opening. The vent assembly includes a body having a bore, a valve seat surrounding the bore, and a check valve disposed within the bore. The check valve is arranged to shift from a closed position seated against the valve seat to an open position disposed away from the valve seat. A plurality of barriers is disposed around and positioned to enclose the check valve. The plurality of barriers is arranged to prevent an external medium from entering the check valve and to provide a tortuous flow path for the exhaust medium reducing sound through the vent assembly.

A digital valve positioner for use with an actuator. The digital valve positioner includes a housing, at least one exhaust port opening formed in the housing, and a vent assembly operatively coupled to the at least one exhaust port opening. The vent assembly includes a body having a bore, a valve seat surrounding the bore, and a check valve disposed within the bore. The check valve is arranged to shift from a closed position seated against the valve seat to an open position disposed away from the valve seat. A plurality of barriers is disposed around and positioned to enclose the check valve. The plurality of barriers is arranged to prevent an external medium from entering the check valve and to provide a tortuous flow path for the exhaust medium reducing sound through the vent assembly.

The present disclosure describes a hydroelectric control valve (HCV) for a fluid pipeline including an inlet and outlet (or input and output) section attached to the same pipeline wherein fluid flows into and out of the HCV comprising a bell reservoir section and a seat reservoir section which are both capped, where the bell reservoir section and the seat reservoir section are aligned with each other and are also perpendicular to fluid flowing through the pipeline. A channel which can be electrically activated and thus controlled is attached to the bell section, such that the bell reservoir section includes a bell relief channel in fluid communication with an outlet section and also a separate hydraulic poppet channel in communication with a locating needle head. In addition, turbine and deactivation channels are employed such that the deactivation channel connects the input section and the seat reservoir.

A washing system that includes a vessel for storing a cleaning solution, an inlet connection point for pressurizing the vessel, and an outlet connection point for dispensing the cleaning solution. In one embodiment, the washing system includes a regulator valve configured to remain open and allow the inside of the vessel to be filled with pressurized gas via the inlet connection point when pressure inside the vessel is below a predetermined value and automatically close when pressure inside the vessel exceeds the predetermined value. In another embodiment, the washing system includes a relief valve (e.g., at the top of the vessel) that is configured to remain closed when pressure inside the vessel is below a predetermined value and automatically open when pressure inside the vessel exceeds the predetermined value.

Disclosed is an apparatus for analyzing the composition of bodily fluid. The apparatus can include a fluid handling network including a patient end configured to maintain fluid communication with a bodily fluid in a patient and a pump unit in operative engagement with the fluid handling network. The pump unit can have an infusion mode, in which the pump unit is operable to deliver infusion fluid to the patient through the patient end, and a sample draw mode, in which the pump unit is operable to draw a sample of the bodily fluid from the patient through the patient end. The apparatus can include a spectroscopic analyzer positioned to analyze at least a portion of the sample; a processor in communication with or incorporated into the spectroscopic analyzer; and stored program instructions executable by the processor to obtain measurements of two or more properties of the sample.

A digital valve positioner for use with an actuator. The digital valve positioner includes a housing, at least one exhaust port opening formed in the housing, and a vent assembly operatively coupled to the at least one exhaust port opening. The vent assembly includes a body having a bore, a valve seat surrounding the bore, and a check valve disposed within the bore. The check valve is arranged to shift from a closed position seated against the valve seat to an open position disposed away from the valve seat. A plurality of barriers is disposed around and positioned to enclose the check valve. The plurality of barriers is arranged to prevent an external medium from entering the check valve and to provide a tortuous flow path for the exhaust medium reducing sound through the vent assembly.

A hydroelectric control valve (HCV) for a fluid pipeline including an inlet and outlet section attached to a pipeline wherein fluid flows into and out of the HCV that comprises a bell section and a seat reservoir section which are both capped, where the bell section and the seat reservoir section are aligned with each other and are also perpendicular to fluid flowing through the pipeline. An electrical poppet channel is attached to the bell section, such that the bell section includes a bell relief channel in fluid communication with an outlet section and also a separate hydroelectric poppet channel in communication with a locating needle head as well as including a turbine and turbine channel where the turbine channel connects the input section and the seat reservoir and where the seat reservoir section includes a seat reservoir relief channel also in fluid communication with the output section.