Patent ID: 7971605

Claim:
An air admittance vent diaphragm assembly for a plumbing, disposal or waste system channel, the assembly having an opening to the channel, the assembly comprising: a base having an annular portion and a stem extending orthogonally from a center of the annular portion, the base made of a rigid material; an annular retainer ring having a circumferential skirt, wherein the circumferential skirt engages the base about the annular portion of the base and the base stem extends beyond the annular retainer ring; and an annular flexible washer, disposed between the annular retainer ring and the annular portion of the base, the washer having a central portion adapted to move bi-directionally; wherein the diaphragm assembly is configured to move to an open position by the channel being below atmospheric pressure, and to a closed position by the channel pressure being equal to or greater than atmospheric pressure; wherein the annular flexible washer forms a seal over the air admittance opening in the closed position; and wherein the stem passes through an opening in the annular flexible washer.