초록 ▼

Fire fighting equipment uses an electronically controlled direct injection foam delivery system. A water pump pumps water through a pipe. A foam pump pumps foam into a mixing chamber within the pipe to produce a water-foam mixture. A microprocessor-based control unit controls the water pump and foam

Fire fighting equipment uses an electronically controlled direct injection foam delivery system. A water pump pumps water through a pipe. A foam pump pumps foam into a mixing chamber within the pipe to produce a water-foam mixture. A microprocessor-based control unit controls the water pump and foam pump. A conductivity sensor is coupled in-line with the pipe for monitoring conductivity of the mixture and providing a feedback signal to the control unit to regulate the foam pump. A speed sensor monitors the foam usage. A second conductivity sensor monitors conductivity of the water and provides a feedback signal to the control unit. The foam delivery system can be controlled by monitoring the flow rate of the water and regulating the foam pump to maintain a constant water and foam mixture. A temperature sensor compensates the regulation process for changes in water and foam mixture temperature.

대표청구항 ▼

What is claimed is: 1. A unit of fire fighting equipment having a direct injection foam delivery system, comprising:a water pump for pumping water through a first pipe;a foam pump for pumping foam through a second pipe;a mixing chamber having a first input coupled for receiving the water and a secon

What is claimed is: 1. A unit of fire fighting equipment having a direct injection foam delivery system, comprising:a water pump for pumping water through a first pipe;a foam pump for pumping foam through a second pipe;a mixing chamber having a first input coupled for receiving the water and a second input coupled for receiving the foam and an output for producing a water and foam mixture;a control unit;a first conductivity sensor for monitoring conductivity of the water and foam mixture and providing a first electrical signal to the control unit;a second conductivity sensor for monitoring conductivity of the water and providing a second electrical signal to the control unit, wherein the control unit controls the foam pump in response to a difference between the first electrical signal and second electrical signal;a flow meter monitors flow rate of the water and provides a third electrical signal to the control unit which in turn controls the foam pump in response to the third electrical signal; anda temperature sensor monitors the water and provides a fourth electrical signal to the control unit wherein:the control unit controls the foam pump flow for changes in water conductivity resulting from changes in water temperature, andthe control unit applies a correction factor to the flow meter to account for changes in water viscosity resulting from changes in water temperature.