Air relief mechanism

An air relief mechanism for use in an opening in a storm door disposed in hinged relationship in the outer side of a casing around a door opening containing an inner door disposed in hinged relationship within the casing, said mechanism comprising:

• an open inner rectangular frame disposed on the inside surface of the storm door and sealed into the periphery of said opening;
• a screen disposed in said inner frame and filling the opening therein;
• an open outer rectangular frame disposed on outside surface of the storm door and sealed into said opening, said outer frame having a slot disposed outside the storm door;
• and
• a flap pivotally disposed in said outer frame between the inner frame and said slot, said flap being biased into a normal first vertical position at which said opening and said slot are isolated from each other,, said flap responding to an air pressure differential developed when one of said doors is moved from open to closed position while the other door is in the closed position to momentarily assume a second inclined position at which said opening and said slot communicate with each other and said differential is quickly reduced to zero.