Improvements in and relating to respiratory apparatus for protection against poisonous and injurious substances

摘要

365,762. Respiratory apparatus. MUNTWYLER, A., Andermatt, Switzerland. Jan. 7, 1931, No. 583. Convention date, Jan. 20, 1930. [Class 81 (ii).] Apparatus for protection against poisonous and injurious solids, vapours, or gases comprises means for drawing in and filtering air, automatically regulating its pressure and quantity as required, and supplying it to respirators having inhaling and exhaling valves. Air is drawn in through any of pipes 1, 2, 3 by means of a fan 5, blower, or the like, and passes through some or all of the filters 7, 71, 711. Reserve filters 8, 81, 811 may be provided. Air taken from tapping points 9, 10 can be analysed in apparatus 11, 12. Purified air passes by a pipe 13, where its temperature and humidity may be adjusted, to a bellows 14 having an air inlet valve 17 actuated by a rod 18 depending from the movable top 16 having a balancing weight 20. The valve casing 171 is made of varying cross section. The pressure in the regulator is varied by altering the load on the top 16. If the air supply fails, a valve 23 is opened by a, rod 21 and air enters from a cylinder 26. A check valve 27 prevents return of air to the filters. The consumer wears a respirator connected to tapping points 28 by a hose 31 which may be divided at the coupling 32, which is secured to a body belt. It is therefore possible for an individual wearing an ordinary respirator to connect himself to the installation without removal of the respirator. Instead of the regulator 14, a similar regulator may be inserted between each respirator and a tapping 28 of the supply pipe 13. Pressure gauges 40 may be arranged at desired points. The whole installation or the individual parts may be portable. The air may be enriched with oxygen which may be supplied in variable doses, or adapted to the air consumption by connecting an oxygen container to the pressure regulator provided with an oxygen inlet valve.