Patent ID: 7275560
Filing Date: 2007-10-02
Classification: F24F,Y10T

Abstract:
1. A pressure relief door system for use in a duct for relieving either positive or negative pressure within the duct, the door system comprising: (a) a frame adapted to be mounted in the duct; (b) a gasket in the frame; (c) a hinged door mounted on the frame by a hinge and sealingly engaging the gasket; and (d) an adjustable pressure relief mechanism normally holding the hinged door against the gasket and permitting the hinged door to open in response to a pressure change; (e) wherein the pressure change can be either positive or negative; (f) wherein the pressure relief mechanism is magnetic; and (g) wherein the pressure relief mechanism further comprises a magnet mounted to the frame, the magnet attracting the door, and wherein the magnet can be moved toward and away from the door hinge, thereby providing decreased and increased opening pressure settings, respectively.