Patent ID: 6196214
Filing Date: 2001-03-06
Classification: F24C

Abstract:
An air extraction hood, which comprisesa canopy which is square or rectangular in plan view; which has a roof, a front wall, a rear wall spaced from the front wall, and a pair of spaced side walls spanning the space between the rear and front walls; said canopy defining an enclosed air collection and treatment zone; said canopy including a downwardly directed air inlet through which air to be treated can enter the zone, as well as an air outlet through which air can be discharged from the zone, and with the air inlet being defined between lower edges of the side walls, and between a first inlet defining member, extending between the side walls and located in proximity to the front wall, and a second inlet defining member, also extending between the side walls and located in proximity to the rear wall at a lower level than the first inlet defining member so that the depth of the hood at the rear wall is greater than its depth at the front wall;mounting means for mounting treatment means inside the canopy in the collection and treatment zone, between the air inlet and the air outlet; andpassageway defining means defining an air passageway between the air inlet and the mounting means along which air can pass, with the passageway defining means comprising the side walls, a first passageway wall between the first inlet defining member and the mounting means and providing a first air deflection surface, and a second passageway wall between the second inlet defining member and the mounting means and providing a second air deflection surface, said second air deflection surface being concave or dish shaped, when the hood viewed end on or in vertical section along a plane extending parallel to the side walls, with at least a portion of the second air deflection surface being curved over at least a major portion of the distance between the air inlet and the mounting means, to enhance air flow along the passageway.