Patent 7628170 was granted and assigned to Emerson Electric on December, 2009 by the United States Patent and Trademark Office.
A flow control valve is provided that comprises a valve housing having an inlet, an outlet, and a valve chamber that includes a first valve port opening in communication with the inlet and a second valve port opening in communication with the outlet. The various embodiments further comprise a modulating member having first and second tapered arcuate slots therein, which is disposed in the valve chamber approximate the first valve port opening and second valve port opening. The modulating member is rotatable to adjustably position a wider or narrower portion of both the first tapered arcuate slot and second tapered arcuate slot over the first valve port opening and second valve port opening respectively, to adjustably vary the rate of fluid flow through the valve.