Abstract: The present invention is an intrinsically safe pneumatically actuated flow controller. A preferred embodiment for the flow controller has a housing assembly defining an inlet port, an outlet port, a pressure signal inlet port, and a main flow path extending between the inlet port and the outlet port. A restriction member is arranged in the main flow path. A first valve assembly and second valve assembly control fluid flow along the main flow path. A first regulator assembly operates the first valve assembly. A pressure signal actuation assembly has an actuation bellows attached to an actuation piston mounted on a flow control piston rod that passes through an isolation plate and is sheathed by an isolation bellows. The flow control piston rod terminates in a flow control piston that engages a second regulator assembly, which operates the second valve assembly based on pressure signals transmitted through the pressure signal inlet to the pressure signal actuation assembly.

Abstract: A flow controller having a first and second stages of regulation. The first stage is a pressure regulation stage that maintains the pressure within an intermediate chamber (formed by a series of interconnected passageways and cavities) within a predetermined range above the pressure in an outlet port. The second stage maintains the flow rate within a predetermined range about a target flow rate. Both stages sample the pressure in the outlet port and automatically adjust the flow of fluid to ensure that fluctuations in pressure at the inlet and outlet ports do not affect the flow rate. The flow rate is set and controlled by a user determined setpoint. The pressure is regulated by one or more feedback systems. The feedback systems used may be mechanical or electromechanical based on a particular operating environment.

Abstract: A flow meter system that calculates mass flow rate based only on a single pressure signal. A flow controller is arranged in parallel with a restriction such that a constant pressure differential is maintained across the restriction. The pressure, and temperature if not controlled, of the fluid flowing through the restriction is measured on either side of the restriction. The pressure is compared to a plot of pressure versus mass flow rate calculated for the specific restriction and fluid being measured. The constant pressure differential maintained across the restriction yields a linear relationship between pressure and flow rate. If temperature is not controlled, the plot of pressure versus mass flow rate will remain linear, but the slope of the curve will be adjusted based on the temperature of the fluid.

Abstract: A flow meter system that calculates mass flow rate based only on a single pressure signal. A flow controller is arranged in parallel with a restriction such that it constant pressure differential is maintained across the restriction. The pressure, and temperature if not controlled, of the fluid flowing through the restriction is measured on either side of the restriction. The pressure is compared to a plot of pressure versus mass flow rate calculated for the specific restriction and fluid being measured. The constant pressure differential maintained across the restriction yields a linear relationship between pressure and flow rate. If temperature is not controlled, the plot or pressure versus mass flow rate will remain linear, but the slope of the curve will be adjusted based on the temperature of the fluid.

Abstract: A flow meter system that calculates mass flow rate based only on a single pressure signal. A flow controller is arranged in parallel with a restriction such that a constant pressure differential is maintained across the restriction. The pressure, and temperature if not controlled, of the fluid flowing through the restriction is measured on either side of the restriction. The pressure is compared to a plot of pressure versus mass flow rate calculated for the specific restriction and fluid being measured. The constant pressure differential maintained across the restriction yields a linear relationship between pressure and flow rate. If temperature is not controlled, the plot of pressure versus mass flow rate will remain linear, but the slope of the curve will be adjusted based on the temperature of the fluid.

Abstract: A flow controller having a first and second stages of regulation. The first stage is a pressure regulation stage that maintains the pressure within an intermediate chamber (formed by a series of interconnected passageways and cavities) within a predetermined range above the pressure in an outlet port. The second stage maintains the flow rate within a predetermined range about a target flow rate. Both stages sample the pressure in the outlet port and automatically adjust the flow of fluid to ensure that fluctuations in pressure at the inlet and outlet ports do not affect the flow rate. The flow rate is set and controlled by a user determined setpoint. The pressure is regulated by one or more feedback systems. The feedback systems used may be mechanical or electromechanical based on a particular operating environment.