Patent ID: 6969044

Claim:
An apparatus for controlling a fluid discharge through an opening in a conduit, comprising: (a) a conduit section including a conduit inlet, a conduit interior, and a conduit exterior, said conduit section also including a conduit outlet having a continuously curved perimeter surface defining said conduit opening that includes oppositely disposed concave sections and oppositely disposed convex sections, wherein said concave and convex sections are continuous, said convex sections are operational to help reduce fan out of the discharge fluid from said conduit opening; (b) a first arcuately curved gate member and a second arcuately curved gate member; (c) means for rotatably mounting said first and second gate members externally to said conduit, said first and second gate members are operational to move from a fully closed position to a fully open position, said first and second gate members in the fully closed position are adjacent to said conduit outlet and have an adjacent interface to each other, as said first and second gate members transition to the fully open position from the fully closed position said first and second gate members remain adjacent to said conduit outlet, said first and second gate members transitioning substantially symmetrically from the fully closed position to the fully open position remaining adjacent to said concave sections in the fully open position; (d) means for moving said first and second gate members between the fully closed position and the fully open position, wherein said first and second gate members are operational to control the fluid discharge through said conduit outlet; and (e) means for substantial fluid sealing between said conduit outlet and said first gate member, between said conduit outlet and said second gate member, between said first and second gate members, and between said first and second gate members interface and said conduit outlet, when said first and second gate members are in the fully closed position.