FIRE PROTECTION FOAM PROPORTIONER WITH CONSTANT MIXING RATIO INCLUDING METERING DEVICE WHICH HAS HYDRODYNAMIC SIMILARITY WITH LOW PRESSURE GENERATOR

摘要

PURPOSE: A fire protection foam proportioner with constant mixing ratio is provided to maintain constant mixing ratio of a foam solution even if the flow characteristic changes, and thus to effectively fight a fire. CONSTITUTION: The fire protection foam proportioner(100) with constant mixing ratio has flow characteristic which changes at front and rear ends. The foam proportioner includes a low pressure generator(111) which is actuated by pressure of water supplied from exterior, and a metering device(116) which is connected to a neck portion of the low pressure generator and regulates the mixing ratio. The metering device has a hydrodynamic similarity with the low pressure generator. The low pressure generator is a venturi, and the metering device consists of the venturi. The low pressure generator is a nozzle and the metering device consists of the nozzle.