Fast and accurate mass flow controller
AssigneeInspiring Atoms Pte Ltd
InventorYang Pan
Life of this patent
Estimating the term…
Abstract
The invention relates to a mass flow controller designed for precise and rapid fluid flow management without using a proportional valve and a proportional-integral-derivative (PID) control loop. It features a solenoid control valve and a controller that uses a calibration database, potentially including a lookup table or neural network, to determine the appropriate solenoid coil current for various fluids, ensuring high-speed and accurate flow control.
Claims20
A mass flow controller, comprising:
- a fluid conducting channel without a proportional pump;
- an inlet structured to receive a fluid into the fluid conducting channel;
- an outlet structured to discharge the fluid via from the fluid conducting channel;
- a solenoid control valve that includes a spring, a plunger disposed in a position in proximity to an orifice within the fluid conducting channel, and a solenoid coil, wherein a solenoid coil current determines the position of the plunger relative to the orifice to control a fluid flow rate through the fluid conducting channel;
- and
- a controller configured to regulate the operations of the mass flow controller by determining the solenoid coil current without using a proportional-integral-derivative (PID) control loop, wherein the solenoid coil current is determined based on a desired fluid flow rate derived from a process recipe and a calibration database stored in the controller, and wherein the calibration database is created through a calibration procedure involving an external flow calibration apparatus connected to the outlet.
A method of controlling the flow rate of a fluid in a mass flow controller including a fluid conducting channel, an inlet structured to receive the fluid into the fluid conducting channel, an outlet structured to discharge the fluid from the fluid conducting channel, and a solenoid control valve that includes a spring, a plunger disposed in a position in proximity to an orifice within the fluid conducting channel, and a solenoid coil, wherein a solenoid coil current determines a position of the plunger relative to the orifice to control a fluid flow rate through the fluid conducting channel, comprising the steps of:
- creating a calibration database by connecting an external flow calibration apparatus to the outlet of the mass flow controller;
- including in the calibration database a relationship between a flow rate and a solenoid coil current for various gases, vapors, and liquids;
- storing the calibration database in a storage unit of the mass flow controller;
- using a controller to determine the appropriate current to be directed to the solenoid coil based on a desired flow rate of a chosen fluid outlined in a process recipe and referencing the calibration database;
- delivering the determined current to the solenoid coil to adjust the plunger of the solenoid control valve to a specific position;
- and
- conducting the fluid from the inlet to the outlet of the mass flow controller without diverting any part of the fluid for flow rate measurement.
A fluid delivery system, comprising:
- a mass flow controller including:
- a fluid conducting channel, an inlet structured to receive a fluid into the fluid conducting channel;
- an outlet structured to discharge the fluid from the fluid conducting channel;
- a solenoid control valve that includes a spring, a plunger in a position in proximity to an orifice within the fluid conducting channel, and a solenoid coil, wherein a solenoid coil current commanded from a controller determines a position of the plunger relative to the orifice to control a fluid flow rate through the fluid conducting channel, wherein the controller is configured to determine the solenoid coil current corresponding to the fluid's flow rate based on a calibration database;
- and
- a flow calibration apparatus designed to be attached to the outlet of the mass flow controller, wherein the calibration database is created using the flow calibration apparatus.
Dependencies are inferred from the claim text.