Patent ID: 6532988
Filing Date: 2003-03-18
Classification: E03C,F16K,Y10T

Abstract:
Air admittance valve adapted for connection to a sanitary waste pipe system having a waste pipe and water traps, the air admittance valve providing for admitting atmospheric air into the waste pipe towards valve function elements of the valve in response to a pressure reduction in the system in order to protect the water traps in the system and to prevent discharge of contaminated air from the system to the atmosphere, the valve comprising a valve body including valve function elements and having:a vertical tubular member adapted to be connected to the waste pipe, the tubular member having an inner space and including an upper section which tapers inwardly and upwardly so that the cross section diminishes at an upper end of the upper section to present an upper conical portion; at least two passages provided in the upper conical portion which communicate air from the inner space of the tubular member towards the valve function elements; a cover member overlying said upper section and having a top wall spaced above the upper end of the tubular member; the valve function elements including a valve member situated between the upper end of the tubular member and the top wall of the cover member, said valve member resting on a valve seat having a sealing surface situated at a level in an horizontal plane passing near the upper end of the tubular member and being freely movable upwards from the valve seat, said valve member having an upper surface and a lower surface; and at least two atmospheric air inlet openings being in communication with the lower surface of the valve member, while the upper surface of the valve member being in communication with the waste pipe system through the at least one passage so as to close said valve member when the pressure in the waste pipe equals or exceeds atmospheric pressure and to open said valve member in order to create an atmospheric air flow passage into the waste pipe when the pressure in the waste pipe is less than the atmospheric pressure, wherein the valve body further comprises an oblong bowl-shaped housing and a partition subdividing the interior of the bowl-shaped housing into mutually opposed orthogonally arranged pairs of first and second chambers, the first pair of chambers being in communication with the surrounding atmosphere via said openings which are provided in the housing and said second pair of chambers being in communication with the lower tubular member and the waste pipe system via the passages in the upper conical portion of the tubular member.