US Patent 9551153 Scupper door systems

A scupper door system includes a frame defining a passageway. A door is mounted within the frame at a pivot and is therein rotatable about the pivot within the passageway between a closed position, blocking the passageway, and an open position wherein the passageway is open to permit passage of water therethrough. A latch mechanism is configured to retain the door in the closed position and is triggerable in response to a preset water condition at one side of the passage to release the door from the closed position and allow the door to rotate to the open position.