FLOW CONTROLLER

摘要

A flow controller includes a body having an inlet end, an outlet end, a flow measurement portion, a variable valve portion and a control portion to control the valve portion based on an output from the flow measurement portion. The flow measurement portion includes a pair of differential pressure sensors for measuring the pressure drop across a flow path as the fluid flows through the flow path. The flow control portion comprises a flexible tube and a plunger with a motor drive that incrementally pinches the flexible tube. A linear, constant diameter bore extends through the housing forming a fluid flow passage for providing a calibrated pressure drop to a fluid that is passed through the fluid flow passage. A replaceable portion of the fluid flow passage is comprised of resilient soft plastic tubing as part of a pinch valve having non-contaminating fittings for positive device shut off.