In order to prevent unnatural behavior of a calculated flow rate, provided is a fluid control device in which a fluid control valve and upstream and downstream pressure sensors are provided on a flow path. The device includes a calculation unit configured to calculate a flow rate based on measured pressures; and an output unit configured to output the calculated flow rate, and exhibit a zero output function of outputting a zero value regardless of the calculated flow rate when the valve is in a closed state. The device is further configured to switch between execution and stop of the zero output function, and when the valve is in an open state and a difference between the measured pressures of the pressure sensors is larger than a threshold, stop the zero output function and cause the flow rate output unit to output the calculated flow rate.

Monitors for evaluating airway procedures, particularly in a pre-hospital environment, are described herein. In an example method, an airway parameter of an individual receiving assisted ventilation is detected by an airway sensor. A monitor determines a metric based on the airway sensor. Further, the monitor performs an action based on the metric.

Included are mass flow controllers and methods of use. An example mass flow controller comprises a flow pathway through the mass flow controller; the flow pathway comprising a first cavity and a second cavity. The mass flow controller further comprises a laminar flow element. The mass flow controller additionally comprises a combination absolute and differential pressure transducer assembly comprising: a third cavity in fluid communication with the first cavity, an absolute pressure transducer exposed to absolute pressure in the third cavity, and a differential pressure transducer exposed to differential pressure between the third cavity and the second cavity. The mass flow controller also comprises a flow control valve assembly downstream of the laminar flow element and the combination absolute and differential pressure transducer assembly.

An actuating and sensing module is disclosed and includes a bottom plate, terminals, a control chip, a partition plate, a gas pressure sensor, a thin gas transportation device and a cover plate. The bottom plate includes terminal grooves, a recess, a gas outlet and a gas relief aperture. The terminals are disposed in the terminal grooves. The control chip is disposed in the recess. The partition plate is stacked on the bottom plate and includes an outlet opening in communication with the gas outlet and a pressure relief orifice corresponding to the gas relief aperture. The thin gas transportation device seals the gas outlet and the pressure relief orifice. The cover plate includes an opening passed through by the thin gas transportation device. The gas is transported to the outlet opening by the thin gas transportation device and sensed by the gas pressure sensor disposed in the outlet opening.

The abnormality detection method of the flow rate control device 10 is performed in the gas supply system 100 including the flow rate control device 10 having the restriction part 12, the control valve 14, the flow rate control pressure sensor 16 for measuring the upstream pressure P1, and the control circuit 19, the inflow pressure sensor 20 for measuring the supply pressure P0, and the upstream on-off valve 2 provided upstream of the inflow pressure sensor, and includes a step of closing the upstream on-off valve in a state in which the gas flows at the controlled flow rate at the downstream of the restriction part by controlling the opening degree of the control valve based on the output of the flow rate control pressure sensor, a step of measuring the drop in the supply pressure P0 on the upstream side of the control valve after closing the upstream on-off valve while keeping the control valve open, and a step of detecting the presence or absence of abnormality in the flow rate control device based on the measured supply pressure drop.

A method may include obtaining first pressure data regarding a first pressure sensor upstream from a restricted orifice and second pressure data regarding a second pressure sensor downstream from the restricted orifice. The method may further include obtaining temperature data regarding a temperature sensor coupled to the restricted orifice. The method may further include obtaining various gas parameters regarding a predetermined gas flowing through the restricted orifice and various orifice parameters regarding the restricted orifice. The method may further include determining a first gas flow rate of the predetermined gas based on a gas flow model, the first pressure data, the second pressure data, the temperature data, the gas parameters, and the orifice parameters.

In a method of monitoring fluid usage in a fluid system, a proportional control valve is provided, including a valve element operable to control fluid flow from a fluid source to the fluid system. A first pressure upstream of the valve element and a second pressure downstream of the valve element are measured to identify a pressure differential across the valve element. In response to the identified pressure differential, the valve element is adjusted to one of a plurality of flow positions to adjust the pressure differential across the valve element to substantially match a predetermined pressure differential. A flow rate through the proportional control valve is determined based on the first pressure, the second pressure, and the adjusted flow position of the valve element. Based on the determined flow rate over time, an amount of fluid usage in the fluid system is determined.

A fluid control system and associated method for pulse delivery of a fluid includes a shutoff valve and a mass flow controller (MFC) upstream of the shutoff valve. The MFC includes a flow channel, a control valve to control flow of fluid in the flow channel, a flow sensor to measure flow rate in the flow channel, and a controller having a valve input from the shutoff valve indicating opening of the shutoff valve. The controller is configured to respond to the valve input to control flow of fluid through the control valve to initiate and terminate a pulse of fluid from the flow channel to the shutoff valve to control a mass of fluid delivered during the pulse of fluid. The valve input can be a pressure signal, and the MFC can include a pressure sensor to sense the pressure signal.

This disclosure describes systems, methods, and devices related to a remote calibration controller. The remote calibration controller may be capable of performing the procedure to remotely test and calibrate differential pressure, static pressure, and temperature on a remotely located fixed orifice plate flow measurement device through the use electromechanical and electro pneumatic hardware located at the site of the flow measurement device that are controlled by on-site controller/logic circuitry remotely accessed via bi-directional communications.

A bi-level positive airway pressure device includes a housing that has a patient port for connecting to an airway of a patient. There is a device (e.g., a nozzle) for generating a positive airway pressure that is directed through a conduit towards the patient port. An exhalation detector includes a nozzle emitting a jet of a gas directed across the conduit and directed at a receptor channel when exhalation gases flow from the patient port, thereby an increase a gas pressure is present at the receptor channel when the exhalation gases flow from the patient port. The exhalation detector converts the increase in the gas pressure into a movement of an occluding member such that when the exhalation gases flow from the patient port, the occluding member moves to block the means for generating the positive airway pressure.