Air inlet grille for engine compartment

Claim 1

In a military vehicle having an engine compartment: the improvement comprising an air inlet grille positioned on the vehicle to remove dust particles from air flowing into the engine compartment; said grille comprising a series of sinuous vanes arranged in spaced parallel relation to define S-shaped air passages; each vane having a chisel-shaped leading edge (18), a rounded convergent trailing edge (22), and two reversely curved side surfaces extending from the leading edge to the trailing edge; each vane being a solid non-hollow structure that is approximately five eighth inch thick measured across the vane side surfaces, whereby grille integrity is maintained when enemy projectiles are directed thereagainst; the vanes being spaced so that the defined air passages have slightly less transverse thicknesses than the vanes; one side surface of each vane comprising a first curved concave air-turn surface (16) extending from the vane leading edge and a curved convex surface extending from the air-turn surface to the vane trailing edge; the other side surface of each vane comprising a curved convex surface extending from the vane leading edge and a second curved concave air-turn surface (20) extending from the last-mentioned convex surface to the vane trailing edge; each vane having a first internal cavity (34) at the downstream end of the first concave air-turn surface, and a second internal cavity (54) near the downstream end of the second concave air-turn surface; a slot communicating each cavity with the immediately adjacent concave air-turn surface; a skimmer wall projecting from the vane at the downstream edge of each slot to deflect concentrated dust through the slot into the associated cavity; the upstream face of each skimmer wall being at an acute angle to the associated air-turn surface to guide dust particles into the slot; each skimmer wall projecting from the vane surface into the adjacent passage through a distance (29) that is in the range of 40% to 50% of the passage width; each slot having a width that is in the range from one tenth inch to two tenth inch; and scavenger fan means connected to each cavity for applying a suction force on each of the associated slots.