Pivot valve and sealing sleeve construction

Claim 1

A valve insert assembly for arrangement in a flow duct comprising an outer tubular duct forming wall, a deformable uniformly concentric insert sleeve arranged within and extending substantially to and evenly spaced from the interior of said duct forming wall along the length thereof and including an end having a beaded formation extending radially outwardly and engaged against said duct forming wall and holding said insert in a spaced location from said duct forming wall, closing means closing said insert with said wall at the end opposite to said beaded formation end, a flap disk of a diameter slightly larger than the interior diameter of said insert sleeve, a pivot shaft for said flap disk concentrically journalled in said duct wall and connected to one side of said flap for concentric pivotal support of said disk in respect to said insert sleeve and being located on the downstream side thereof, said flap being engageable in a closed position with said insert sleeve intermediate its length at a spaced location from said beaded formation end; said beaded formation of said insert sleeve being located on the upstream side end, said tubular duct forming member having a flange at one end forming an interior radially outwardly extending groove, said insert sleeve having a beaded portion extending into the groove and holding the remaining portion of said insert sleeve away from the interior wall of said tubular duct forming member, a channel member secured to said duct forming member and adapted to be secured to the duct inwhich the assembly is to be positioned, and located at the downstream side of said flap valve and comprising said closing means, said insert sleeve having an end extending into said channel member.