Improvements in or relating to filters

摘要

838,327. Filters. AUTOMOTIVE PRODUCTS CO. Ltd. Dec. 15, 1958 [Dec. 13, 1957], No. 38860/57. Class 46. A method of forming a filter element consists of forming a felt strip 10, Fig. 1, of greater width A than the length B of the filter element to be formed therefrom, cutting the strip longitudinally through part of its thickness along lines 11 spaced apart by the distance B so as to leave marginal strips 12 of equal width, folding the strips 12 against one face of the central part of the strip, folding the strip to zig-zag form along transverse lines and joining the ends of the strip to form a continuous wall. A strip of wire mesh 13, Fig. 4, or other suitable material may be secured to the strip prior to folding into zig-zag form to strengthen the element.