Hypro Corporation

Sta-rite Industries Inc.

Fire Research Corp.

Robert S Horeck

Lawrence C Arvidson

Robert L Hosfield

Duane A Brown

Embodiments of the invention provide a foam proportioning system. The foam proportioning system can include a foam pump, at least one foam line, a divert, and at least one controller. The divert can direct a portion of a flow of a liquid foam concentrate downstream of the foam pump back through the foam pump. The controller, which can be in communication with the foam pump and the divert, can be configured to automatically maintain a minimum flow rate of the liquid foam concentrate through the foam pump.

Foam proportioning system with low-end controller

A fire fighting vehicle of the type having a system for introducing a liquid foam concentrate into a water delivery hose so that the percentage concentration of foamant in the mixture remains at a predetermined set value irrespective of variations in the water flow rate. The improvement provided involves the addition of an AutoStart feature whereby upon application of power to the foam control system, the system comes up in an on mode without the need for human intervention.

Fire fighting foam injection system with auto-start feature

A fire-fighting system in which multiple water discharge lines each have associated with them a foam concentrate delivery line where each of the foam concentrate delivery lines are supplied from a foam concentrate tank by way of a positive displacement pump having the capability of having its flow rate adjusted. Each of the water discharge lines includes a flow meter as do all of the foam concentrate delivery lines. The foam concentrate delivery lines also include a valve whose orifice size is electrically controlled. Associated with each of the foam concentrate delivery lines is a microprocessor-based line controller module that receives inputs from the flow meters in the water discharge lines and the flow meters in the foam concentrate delivery lines whereby the proportion of foam concentrate to water in the separate water discharge lines can be set at predetermined values. A main microprocessor-based controller is coupled to each of the several line controllers and the output of the main controller is used to adjust the output flow rate of the foam concentrate pump.

High flow foam system for fire fighting applications

A system for monitoring the volume rate of flow and total volume of liquid being drawn from a supply by way of a plurality of discharge conduits includes a flow meter transducer for associated individually with each of the discharge conduits with the transducers providing pulse information to associated flow meter circuits that are connected in series relationship with one another and to a master control module. Each of the individual flow meter circuits includes a pair of microprocessors, one for determining from the pulse information of its associated transducer the volume rate of flow of liquid out its associated discharge conduit. The second microprocessor is programmed to combine the flow information from its own transducer with combined flow information from an adjacent upstream flow meter circuit in the series string and produces a combined flow output signal for delivery to an adjacent downstream flow meter circuit. In this fashion, flow information associated with each of the discharge conduits can be individually displayed with the total volume rate of flow information being presented on a visual display associated with the master controller.

Flow meter system with remote displays for each discharge

A microprocessor-based dual tank control system for use in a foam-injection fire fighting system which automatically proportions the selected foamant into the main water stream at a predetermined concentration, automatically provides an accurate assessment of the amount of foam pumped out of the selected supply tank, and automatically flushes the injection line at system power-up and between flow cycles.

Dual tank control system and method for use in foam introduction fire

A fire extinguishing system in which a calculated quantity of a liquid chemical foamant is introduced into the main water stream being directed at a fire equipped with a protective circuit for limiting the amount of average current flowing within a motor driving a fluid pump used to inject the chemical foamant, in addition to an electronic fuse circuit for automatically shutting off the power being supplied to the low-level electronics.

Current limiting circuit and electronic fuse for use in foam injection

A fire fighting system introduces a liquid chemical foam concentrate into a water stream. The system may incorporate either or both of a hydraulic motor driven pump under control of a microprocessor-based hydraulic valve driver and an electric motor driven pump under control of a DC motor drive circuit. The DC motor drive circuit is adapted to be connected in electrical communication with the hydraulic valve driver and with a display/controller also incorporating a microprocessor. When operating in the dual mode, when the quantity of chemical foamant that must be added to the water stream to maintain a desired percentage mixture exceeds the capacity of the electric motor driven foam pump, control is transferred, via the hydraulic valve driver, to allow a hydraulic motor to drive a separate foam pump. In this fashion, the electric motor driven foam pump can cover a first range of flow rates from a very low rate to an intermediate rate and the hydraulic system then taking over to extend the range from the intermediate flow rate to a relatively high flow rate.

System for introduction of concentrated liquid chemical foamant into a

A fire-fighting system in which a liquid chemical foamant is introduced into the water stream in varying amounts so as to maintain a predetermined percentage mixture irrespective of variations in the water flow includes a motor-driven pump where the motor is controlled over a first speed range by pulse width modulating the drive to the motor and over a second speed range, producing intermittent motion, by burst width modulating the drive signal when it is operating at its minimum pulse width modulated duty cycle. Using this technique the range of available motor speeds is extended well beyond that which can be achieved using pulse width modulation of the motor drive signal alone.

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Fridley, MN, United States of America

Robert S Horeck