GB251950A - Improvements in or relating to the production of fire-extinguishing foam - Google Patents

Abstract

251,950. Excelsior Feuerl÷schgerõte Akt.-Ges., (Assinees of Burmeister, H.). May 8, 1925, [Convention date]. Grant of Patent opposed. Fire - extinguishing by foam.-In the production of foam dry chemicals in controllable quantities and in correct proportions for forming foam are allowed to fall into a device from which they are conveyed in a dry state or mixed with water to a continuous current of water in which foam production takes place. In the apparatus shown, a container a is divided by a conical partition b into upper and lower compartments c, d. Mixed chemicals are placed in the compartment c, or this compartment may be divided by a partition to keep the chemicals separate. The latter fall through a controllable opening e into the solution compartment d, where they are dissolved by water from a flushing device f supplied by a by-pass from the main water pipe under control of a valve h. The main pipe includes a two-stage ejector of which the first stage g<1> draws in a liquid foam reagent from a vessel i, and the second stage g draws in the solution from the compartment d. The foam reagent may be mixed in a dry state with the chemicals and the ejector may be replaced by a pump. A three-stage steam injector may be employed if very cold water only is available. A battery of containers a may be employed, each containing one of the reacting chemicals.