Magnetic latch for exhaust vent

A latch for use with an exhaust vent in which the vent comprises a fixed face plate on one side of which is an inlet for admitting air expelled from a blower, and on a directly opposite side of which is an air exhaust outlet for discharging such air into an outside atmosphere, and a valve for controlling the passage of air through the vent, said valve comprising a hingedly suspended valve plate operatively coupled to said exhaust outlet, said valve plate having an inside and an outside face, with the inside face presenting toward said fixed face plate and closing the valve by moving against said fixed face plate in the absence of blower expelled air, and said outside face communicating with said outside atmosphere,

• wherein said latch comprises at least one substantially flat plastic bonded magnet having a first face to which is bonded a layer of pressure sensitive adhesive and having an opposite second face for magnetic interactions, and an associated strike plate formed of a thin strip of a conformable magnetically susceptible material having a first portion to which is bonded a layer of pressure sensitive adhesive material, and having a second portion adapted to be magnetically engageable with and separable from said second face of the magnet,
• said first portion of the strike plate being adapted to be deformed to match the contour of either said fixed face plate or valve plate, and to be secured thereto by means of the pressure sensitive adhesive carried on the first portion while the second portion is positioned out of the airstream, and the magnet being adapted to be secured to the other of the valve plate or fixed face plate and to be appropriately positioned thereat by first magnetically coupling the second face of the magnet and second portion of the strike plate together and then by bringing the other of the fixed face plate or valve plate into contact with the adhesive carried on the magnet, thereby causing the other of the fixed face plate or valve plate to be secured to the magnet while ensuring that the magnet and strike plate are optimumly located with respect to magnetic attraction forces,
• said magnetic forces being operative in the absence of blower expelled air hold the valve in its closed position despite impulse torque imparted on the valve plate by pressure differentials resulting from gusts of wind to which the said outside face of the valve plate may be subjected, necessitating more intense impulse torques associated with more intense gusts before the valve will inadvertently open, while at the other extreme, the magnetic forces are sufficiently small as to be inoperative to hold the valve closed in the presence of blower expelled air.