Adjustable grille

Claim 2

An adjustable grille assembly comprising: a housing having an upper, a lower, and side walls, the forward end of the upper wall extending beyond the forward end of the lower wall, thereby defining a housing mouth which recedes in a downward direction; a grille frame defining a fluid flow passage pivotally mounted within the mouth of said housing about a horizontal axis, said axis passing through an upper portion of said frame and an upper portion of said housing, said grille frame including a convex bottom wall in substantially continuous sliding contact with the forward end of the lower housing wall, a pair of side walls, a top wall, and a plurality of vanes, each vane being pivotally mounted between the top and bottom frame walls, said convex bottom wall having a leading edge and a trailing edge and slot means formed therethrough adjacent said trailing edge for diffusing the fluid passing into said grille frame in a downward direction when the grille frame is directing the bulk of the fluid through said vanes in an upward direction; and detent means formed on the lower surface of said convex bottom wall adapted to cooperate with said forward end of the housing lower wall to selectively fix said grille frame in a particular position; wherein the grille frame is adapted to be retractable from a first position in which the frame extends substantially outside of said housing to a second position in which the frame is substantially within the housing.

Claim 3

An adjustable grille assembly comprising: a housing having an upper, a lower, and side walls, the forward end of the upper wall extending beyond the forward end of the lower wall thereby defining a housing mouth which recedes in a downward direction; a grille frame defining a fluid flow passage pivotally mounted within the mouth of said housing about a horizontal axis, said axis passing through an upper portion of said frame and an upper portion of said housing, said grille frame including a convex bottom wall in substantially continuous sliding contact with the forward end of the lower housing wall, pair of side walls, a top wall, and a plurality of vanes, each vane being pivotally mounted between the top and bottom frame walls, wherein the length of the arc described by said convex bottom frame wall is at least as long as the distance between a first point and a second point located in the same vertical plane, said first point being on the upper housing wall located rearwardly of said axis a distance equal to the radius of curvature of the bottom frame wall and said second point being on the forward end of the lower housing wall, so that when said grille frame is moved to said second position, the trailing edge of said convex bottom wall abuts against the upper housing wall and said bottom convex frame wall therefore extends substantially between the upper, lower and side walls of said housing; and detent means formed on the lower surface of said convex bottom wall adapted to cooperate with said forward end of the housing lower wall to selectively fix said grille Frame in a particular position; wherein the grille frame is adapted to be retractable from a first position in which the frame extends substantially outside of said housing to a second position in which the frame is substantially within the housing.

Claim 4

An adjustable grille assembly comprising: a housing having an upper, a lower, and side walls, the forward end of the upper wall extending beyond the forward end of the lower wall thereby defining a housing mouth which recedes in a downward direction; a grille frame defining a fluid flow passage pivotally mounted within the mouth of said housing about a horizontal axis, said axis passing through an upper portion of said frame and an upper portion of said housing, said grille frame including a convex bottom wall in substantially continuous sliding contact with the forward end of the lower housing wall, pair of side walls, a top wall, and a plurality of vanes, each vane being pivotally mounted between the top and bottom frame walls, wherein the length of the arc described by said convex bottom frame wall is at least as long as the distance between a first point and a second point located in the same vertical plane, said first point being on the upper housing wall located rearwardly of said axis a distance equal to the radius of curvature of the bottom frame wall and said second point being on the forward end of the lower housing wall, so that when said grille frame is moved to said second position, the trailing edge of said convex bottom wall abuts against the upper housing wall and said bottom convex frame wall therefore extends substantially between the upper, lower and side walls of said housing; and detent means formed on the lower surface of said convex bottom wall adapted to cooperate with said forward end of the housing lower wall to selectively fix said grille Frame in a particular position; wherein the grille frame is adapted to be retractable from a first position in which the frame extends substantially outside of said housing to a second position in which the frame is substantially within the housing.

Claim 5

An adjustable grille assembly as recited in claim 2 further including aperture means formed in said convex bottom wall of said grille frame for permitting fluid flow through said convex bottom wall and out of said grille frame when said grille frame is in said second position.