Air vent with snap-fit cover for foundation walls

Abstract

A combination of an air vent for passing air through an opening of a wall around an enclosed area, to facilitate ventilation, and a cover readily installable on and removable from the air vent are disclosed. The air vent includes a peripheral flange surrounding a central opening and a screen fixed to the air vent and covering the central opening. The air vent may include fixed false louvers and may bear surface texturing for esthetics. The cover is dimensioned and configured to overlie the central opening and may be releasably held in place by opposed deflectable tabs formed integrally therewith. Each of the tabs has a projection configured to enter and occupy a corresponding hole in the air vent. The tabs may be deflected to remove the projections from their respective holes, thereby releasing the cover from the air vent.

I claim: 
     
         1 . A combination of an air vent for passing air through an opening of a wall around an enclosed area, to facilitate ventilation, and a cover for blocking air from passing through the opening, wherein the cover is readily installable on and removable from the air vent, the combination comprising:
 an air vent including a central opening for ventilation, a screen fixed to the air vent and covering the central opening, a planar peripheral flange surrounding the central opening,   wherein the peripheral flange occupies a plane perpendicular to a direction of flow of air through the central opening, and false louvers covering the screen, the false louvers arranged to leave the central opening unobstructed for passage of air past the screen; and   a cover dimensioned and configured to overlie the central opening in a deployed position and to block air flow through the air vent when the cover is installed, wherein   one of the air vents and the cover includes at least one integral deflectable tab configured to engage by snap fit the other of the air vent and the cover, and to releasably couple the air vent to the cover.   
     
     
         2 . The combination of  claim 1 , wherein the other of the air vent and the cover has at least one hole, and the at least one deflectable tab includes a projection configured to enter and occupy the at least one hole in the other of the air vent and the cover when the at least one deflectable tab is not deflected, and to be released from the at least one hole when the deflectable tab is deflected. 
     
     
         3 . The combination of  claim 2 , wherein
 the air vent has a right side and a left side when installed over the opening of the wall,   the at least one deflectable tab comprises a first tab at the right side of the air vent and a second tab at the left side of the air vent; and   the at least one hole comprises a first hole at the right side of the air vent and a second hole at the left side of the air vent.   
     
     
         4 . The combination of  claim 3 , wherein the first tab and the second tab are each defined on three sides by a slot formed in the air vent and are attached to the air vent at a living hinge defined on a fourth side. 
     
     
         5 . The combination of  claim 3 , wherein the first tab and the second tab are on the cover, and the first hole and the second hole are in the air vent. 
     
     
         6 . The combination of  claim 5 , wherein the cover comprises an access opening dimensioned and configured to enable a person to insert a finger thereinto and impose pressure on the air vent in a direction releasing the cover from engagement with the air vent. 
     
     
         7 . The combination of  claim 5 , wherein the air vent comprises a perimetric projection perpendicular to the peripheral flange and surrounding the central opening, and the first hole and the second hole are in the perimetric projection of the air vent. 
     
     
         8 . The combination of  claim 7 , wherein the perimetric projection is double walled and hollow in cross section along at least most of a length of the perimetric projection. 
     
     
         9 . The combination of  claim 7 , wherein the air vent further comprises a central wall dividing the central opening into a right portion and a left portion. 
     
     
         10 . The combination of  claim 9 , wherein the false louvers are coupled to the perimetric projection at the right side of the air vent, at the left side of the air vent, and at the central wall of the air vent, and wherein
 each false louver comprises a gusset perpendicular to the false louver and spanning the respective false louver and the right side and the left side of the air vent, and   each gusset seals an end of a respective false louver against loss of air from air flow at the false louver through the air vent to lateral air flow not passing through the air vent.   
     
     
         11 . The combination of  claim 1 , wherein the cover is made substantially from one or more plastic materials by pressure molding. 
     
     
         12 . The combination of  claim 11 , wherein the plastic material comprises ABS (acrylonitrile butadiene styrene) plastic material. 
     
     
         13 . The combination of  claim 1 , further comprising decorative surface texturing on the air vent and on the cover.