Mass flow controller

摘要

A mass flow controller includes a base having a passage that allows a fluid to pass through the passage. A first control valve controls a mass flow of a fluid passing through the passage. A second control valve controls a full scale of the mass flow of the fluid. A bypass portion is disposed in the passage through which the fluid passes. A mass flow sensor measures the mass flow of the fluid passing through the bypass portion. The second control valve is connected to the passage adjacent to the bypass portion for controlling the full scale of the mass flow of the fluid passing through the bypass portion.