초록 ▼

An air duct has a filter mount opening originally intended to accept a shallow filter element for filtering air entering the duct. The opening has an interior flange whose original purpose was to support the shallow filter element. This flange has interior edges defining an air passage opening. The

An air duct has a filter mount opening originally intended to accept a shallow filter element for filtering air entering the duct. The opening has an interior flange whose original purpose was to support the shallow filter element. This flange has interior edges defining an air passage opening. The invention is implemented a filter unit including a frame and a deep filter element mounted in the frame. The frame has dimensions allowing the filter unit to replace the conventional shallow filter element with the frame inserted into the air passage opening and closely spaced to all of the interior edges. A resilient gasket is mounted adjacent to the opening's interior flange and projects slightly into the air passage opening so as to contact the deep filter element's frame. The gasket prevents air leakage between the interior flange's interior edges and the frame. In one embodiment, the frame has a flange to mate with a surface of the air passage opening's interior flange so as to prevent air leakage and to position and support the filter unit.

대표청구항 ▼

[ What is claimed is:] [1.] An air filtering system including a filter unit for installation in a filter mount opening of an air duct to replace a shallow rectangular filter element, said air duct having an axis defining the general direction of air flow, said filter mount opening having an interior

[ What is claimed is:] [1.] An air filtering system including a filter unit for installation in a filter mount opening of an air duct to replace a shallow rectangular filter element, said air duct having an axis defining the general direction of air flow, said filter mount opening having an interior surface, and projecting centrally therefrom an interior peripheral duct flange having a mating surface facing along the air duct axis and interior edges defining an air passage opening, said mating surface adapted to receive the periphery of the shallow filter element, said filter unit having first through fourth panels defining the periphery of the filter unit and together forming a frame for the filter unit, said filter unit frame dimensioned to fit into and project through the air passage opening with close spacing of the first through fourth panels to adjacent interior edges of the flange, said system including a resilient flange gasket disposed along the duct flange and extending past the duct flange edge and into the air passage opening adjacent to the duct flange, said flange gasket for contacting the filter unit's adjacent panel, for forming a seal between the flange and the adjacent panel, and for opposing air flow between the flange interior edge and the filter unit's adjacent panel.