Abstract: A grease hood and plenum apparatus is mounted at the ceiling of a restaurant kitchen, and incorporates grease filters and also means to direct make-up air toward such filters. The make-up air passes through a capture chamber the bottom of which is open for reception of fumes from a cooking appliance disposed in the kitchen. An extended exhaust plenum chamber projects upwardly from the hood to draw air and fumes through the filters, and a supply means extends upwardly from the hood to supply make-up air thereto. Blower means deliver make-up air to the supply means and also draw air and fumes from the extended exhaust plenum. The kitchen ceiling has an opening or hole sized and shaped to receive downwardly the grease hood in premanufactured condition, and means are provided to support the greaee hood at the opening and at least partially below the level of the ceiling so that fumes may pass upwardly into the capture chamber.

Abstract: The grease hood has a small dimension in the front-to-rear direction, and encloses a relatively large vortex the maximum vertical dimension of which is about equal to or greater than the maximum horizontal dimension thereof. The maximum diametral dimension of the vortex in a direction generally perpendicular to the grease-filter means is about equal to or less than the maximum diametral vortex dimension in a direction generally parallel thereto. In one illustrated embodiment, the vortex is generally circular, whereas in a second illustrated embodiment the vortex is generally elliptical and vertically elongated.The grease-filter means in one illustrated embodiment is not planar but instead is curved, the curvature cooperating with the curvature of the vortex liner to permit achievement of benefits including relatively small size of the grease hood. More specifically, the curved filter is associated with the vortex liner of generally circular shape in such one embodiment.

Abstract: A grease hood and plenum apparatus is mounted at the ceiling of a restaurant kitchen, and incorporates grease filters and also means to direct make-up air toward such filters. The make-up air passes through a capture chamber the bottom of which is open for reception of fumes from a cooking appliance disposed in the kitchen. An extended exhaust plenum chamber projects upwardly from the hood to draw air and fumes through the filters, and a supply means extends upwardly from the hood to supply make-up air thereto. Blower means deliver make-up air to the supply means and also draw air and fumes from the extended exhaust plenum. The kitchen ceiling has an opening or hole sized and shaped to receive downwardly the grease hood in premanufactured condition, and means are provided to support the grease hood at the opening and at least partially below the level of the ceiling so that fumes may pass upwardly into the capture chamber.

Abstract: The entry or intake portion of a grease-hood system is mounted at a low elevation, far below the elevation of the head of the cook. Furthermore, such entry portion does not extend clear to the front of the cooking appliance disposed therebeneath, thus the cooking appliance protrudes outwardly from beneath the entry portion. The apparatus and method are such that the flow of fumes and air from the cooking appliance to the entry portion of the hood is substantially entirely the result of convection. There is, however, a forced flow in the hood system at a region above the entry portion, the forced flow being such that fumes and air are directed at the grease filter means. In the forced-flow portion of the system, air from outside the room is passed directly to the grease hood, and air and fumes which pass through the grease filter means are passed to a region exterior to the room and/or are recirculated back to the hood. There is a vortical flow of air and fumes in the forced-flow portion of the system.

Abstract: A greatly extended plenum chamber, comprising a plenum or exhaust chamber and a plenum extension connected thereto, is employed in combination with grease filters which operate by impingement and by centrifugal action. Furthermore, a stream of air is directed against the upstream surfaces of the filters. The result of the combination is a surprisingly effective removal of grease and smoke from cooking fumes, with consequent minimization of grease coatings on the surfaces of the plenum chamber and of the exhaust blower connected thereto. When space does not permit vertical installation of a large extended plenum chamber, portions of such chamber may be inclined from the vertical and/or may be replaced by a plurality of smaller plenum extensions.In an additional embodiment, the effect of a very large plenum extension is obtained by a single and much smaller plenum extension.

Abstract: A vortex-type smoke hood, in which the liner of the hood is substantially continuously curved in such manner that the vortex action is improved greatly. One result is that the supply air velocity may be increased by a major amount, without causing "bouncing" of air and fumes out of the hood. The curved wall produces the additional benefit of rendering more smooth the flow path of the inlet air.In a second embodiment, a plate shelf and/or pass-through are combined with the hood, creating a very convenient relationship and one whereby the cook remains highly comfortable.