Air-conditioning filter - of extended life and improved efficiency

摘要

A fibrous material is gripped between two, pref. moulded plastic, frames having very large apertures between widely-spaced cross bars having a cross-section with a high resistance to bending in the direction of flow through the filter e.g. 'U'-channel and 'T'-section. Gives less resistance to air flow cf. perforated cardboard or foil encased fibre pads and the frames are stiff enough to eliminate the metal support grid previously employed.