GB396360A - Filter box for respirators and other uses, and a method for charging this box - Google Patents

Abstract

396,360. Respiratory &c. filters. FERNEZ, M., 40, Rue de Vitry, Alfortville, France. Oct. 27, 1931, No. 29738. Convention date, Nov. 3, 1930. Void [Published under Sect. 91 of the Acts]. [Class 81 (ii).] A filter-box A, particularly for use with respirators, comprises a number of superposed chambers, B<1>, B<2>, B<3>, for example three, each containing granular filter material a and communicating with a central duct D. The chambers are formed by the lower end of the box A itself and by containers B<2>, B<3>, having central depending tubes F<1>, F<2> passing through the filter material in the next lower chamber. Air or gas, entering at C, is distributed direct to each of the chambers and, passing through one layer of filter material only, emerges at D. The material a is retained by reticulated screens I, H, and by springs G, G<1>, beating against the top of the box A and against the cross-members F preferably hooked on to the box. The members F also support the containers B<1>, B<2>. In charging the box A a rod of the same diameter as the tube E<2> is inserted into the box while filling the chamber E<2> ; the tube E<2> is then attached to the rod and drawn downwardly through the material a ; the same method is adopted for filling the container B<2>.