Method and apparatus for monitoring liquid flow through an enclosed stream

摘要

A liquid flow meter is designed to monitor the flow of a liquid through an enclosed stream such as through the tubes or internal passageways of a device such as a filtration system. The liquid flow meter includes an axial-flow magnetic turbine and a detector such as a reed switch that monitors turbine rotation by counting pulses. The counted pulses are then used to determine the aggregate volume of liquid that has flowed through the flow meter. When the liquid flow meter is used in a domestic potable water filtration system or in a similar application, the counted pulses can also be used in conjunction with a timer to determine liquid flow rate as well as the remaining useful life of a filter cartridge of the filtration system and/or of the remaining volumetric filtration capacity of the filter cartridge. The liquid flow meter exhibits high linearity or consistency of flow measurement over a wide range of liquid flow rates-even at very low pressures and low flow rates. The liquid flow meter also exhibits a very small pressure drop thereacross, requires minimal electrical power for operation, and is also compact and versatile so as to be usable with minimal modification to existing filter assembly designs.