Patent ID: 8267756
Filing Date: 2012-09-18
Classification: B08B,F24C

Abstract:
1. An extraction hood for suction extraction and/or purification of a carrier substance, contaminated with solid and/or liquid substances, the extraction hood comprising: a housing having at least one inlet and one outlet orifice; a conveying device for conveying the carrier substance through said housing and having an adjustable conveying power; a filter unit spaced upstream from the conveying device, and through which the carrier substance flows; and a prefilter unit disposed upstream of said filter unit on a suction side and through which at least a portion of the carrier substance flows, wherein said prefilter unit defines an at least partially peripheral suction gap that increases flow velocity and reduces condensation at the at least partially peripheral suction gap, wherein carrier substance passing through the at least partial suction gap, by-passes the prefilter unit.