GB454897A - Improvements in filtering cartridges - Google Patents

Abstract

454,897. Gas filters. SOC. ANON. ALFA COLAS, L., COLAS, J., and COLAS, A., 199, Rue du Faubourg St.-HonorÚ, Paris. Nov. 18, 1935, No. 31946. Convention date, Nov. 19, 1934. [Class 8 (ii)] [See also Group VI] A gas filter, for use particularly in gas mask canisters comprises circular or other plates 8, 15, Fig. 1, of filter material having between them cardboard or other spacing elements 10 of the same contour. The filter plates each have two apertures (except for the end plates 8 which have one aperture only). The spacing elements, Fig. 4, comprise a ring 10 enclosing a circular wall 12 surrounding an aperture 13, and having extending therefrom a diametral web 11 carrying a part circular wall 14 defining gaps 25 and a second aperture 141. The elements 10 are mounted alternately in the position shown and in laterally reversed position, the apertures 13, 14<1>, registering with the filter plate apertures to form inlet and outlet passages 1, 2, Fig. 1. In order to prevent flow between the edges of the filter and spacing members stainless steel or other flanged rings 32 are inserted between them, the adjacent rings being mutually inverted. The cylindrical portions of the rings extend over the edges of the filter plates and protect the adjacent filter-spacer edges. In-flowing gas passes through the gaps 25 in passage 1 where these occur, into the spaces enclosed by the corresponding spacing element, through the adjacent filter plates, and emerges into passage 2 through the gaps 25 in the adjacent spacing plates. Gas also penetrates normally and laterally through filter plate 8. The pile is assembled under pressure between end plates 6, 20, each having one aperture corresponding to the passages 1, 2, and having central cutaway portions, the end plates being provided with lugs 18, 21 which are engaged by apertures 23, 24, in holding strips 22, the lugs then being turned up.