Patent ID: 8517230

Claim:
A valve for controlling dense phase flow of a granular material and air, comprising: a cylindrical valve body having an inlet, a discharge downstream of the inlet, and an end offset from the inlet; a stop member positioned between the discharge and the end; an axial bore formed through the stop member; a connecting member slideably extending through the axial bore; an axial passageway formed in the connecting member; a disk coupled to a first end of the connecting member defining an annular surface configured to slideably engage an interior surface of the cylindrical valve body; at least one passageway formed in the disk extending through the annular surface and in fluid communication with the axial passageway formed in the connecting member; a piston coupled to a second end of the connecting member and configured to slideably engage and substantially seal against the interior surface of the cylindrical valve body; a chamber defined between the piston and the end of the cylindrical valve body; and a flexible diaphragm operatively coupled to the disk proximate the annular surface of the disk and in fluid communication with the passageway formed in the disk; wherein the disk is moveable between a flow position at which the granular material and the air flow from the inlet toward the discharge and a plugged position at which the granular material is substantially prevented from flowing through the discharge; wherein the flexible diaphragm is moveable between a sliding position and a sealing position at which the flexible diaphragm engages the interior surface of the cylindrical valve body; and wherein applying an activation medium to the chamber urges the piston toward the stop member and the disk toward the inlet and beyond the discharge to substantially stop the flow of granular material through the discharge, and urges the flexible diaphragm from the sliding position to the sealing position to substantially stop the flow of air through the discharge.