Combination air pipe connector and flow measurement device

A combination air pipe connector for connecting a pair of air pipes and flow measurement device comprising

• a cylindrical conduit for connecting the air flow between the spaced ends of said air pipes, said conduit having a constant diameter inner wall,
• means for respectively securing the ends of the air pipes in tight sealed engagement about the opposed ends of the conduit,
• a flat orifice plate having a flat upstream face and a flat downstream face in opposed relationship thereon and a plurality of generally uniformly spaced passages extending therebetween and generally throughout the area of the faces, said orifice plate being rigidly fixed within the inner wall of the conduit without the addition of any additional retaining structure at the outer edge thereof so that said inner wall extends to the faces of the orifice plate,
• a mounting member having a central portion thereof secured about the conduit and the orifice plate therein and a pair of cylindrical end portions extending outwardly of the central portion in parallel spaced relationship to the outer wall of the conduit so as to provide a pair of cylindrical recesses for the reception of said spaced ends of the air pipes, said central portion of the mounting member and said conduit each being provided with a pair of radially extending passageways aligned so as to respectively communicate with the air in the conduit directly adjacent to the upstream and downstream faces of said orifice plate, said passageways having outer ends spaced radially outward of the conduit,
• and a pair of spaced valves mounted upon the central portion of the mounting member at the outer ends of the radially extending passageways, said valves being arranged for coupling to a differential pressure meter for determining the pressure difference across said orifice plate in order to determine the air flow rate therethrough.