Patent ID: 7988544

Claim:
A vent assembly for attachment to a fluid discharge conduit comprising: a mount having an opening, said opening adapted to receive the conduit; and a door pivotally received by said mount for covering said opening, said door having a center of gravity and including a first surface portion for covering at least a portion of said opening, a second surface portion for covering another portion of said opening and joined to said first surface portion, a mounting flange coupled to said second surface portion, and a hinge having a rotational axis of said door at said mounting flange; said first surface portion having forward and rearward portions; said second surface portion defining a forward plane opposite said first surface portion, said second surface portion extending rearwardly from said forward plane and protruding into said opening, wherein said forward plane is substantially vertical when said door is in a closed position; said center of gravity of said door located between said forward plane and said first surface portion; a portion of said mounting flange extending substantially along said forward plane and contacting a front surface of said mount when said door is in the substantially vertical closed position to substantially prevent said door from pivoting inwardly beyond the closed position; said mounting flange extending rearwardly from said forward plane to space said rotational axis rearwardly from said forward plane a distance such that said rotational axis is positioned rearwardly of said forward portion of said first surface portion and forwardly of said rearward portion of said first surface portion when said door is in the closed position, and to position said hinge directly above or rearwardly of the center of gravity of said door when said door is in the closed position; and wherein said door is operable for displacement with respect to said opening between an open position and said closed position when said door is engaged by fluid flowing through the discharge conduit, said door being in said open position only after said door pivots sufficiently to move said first and second surface portions fully out of said opening, whereby birds, animals, and the like are restricted from entering the conduit.