A fluid flow meter is provided and comprises a tubular and cylindrical
housing constructed of a transparent material and having an upper
axial end, a lower axial end and defining an interior fluid chamber
therebetween. A fluid inlet is fluidly connected to the lower end
of the chamber while a fluid outlet is fluidly connected to the
upper end of the chamber. At least one and preferably several flow
responsive members are disposed and freely moveable within the interior
of the fluid chamber. The members have a density greater than the
density of the fluid flowing through the flow meter but are vertically
displaceable within the interior chamber in an amount proportional
to the fluid flow rate through the flow meter. The density and surface
area of the members can be varied as desired in order to provide
for different flow rates and flow ranges. In addition, in the preferred
form of the invention, a magnetically operated switch is adjustably
connected to the housing and is actuated by the presence of a flow
responsive member at a predetermined vertical level within the fluid
chamber and is thus representative of a predetermined flow rate.
This invention relates to a flow meter of a fluidistor oscillator
type, which has its principal use when measuring the ventilation
of a moving human being or animal. Thanks to the special design
of the flow meter it can be made small, light and portable at the
same time as the pressure drop in it is minimal.
Electrodes for an electromagnetic flow meter are mounted through
a pipe wall using pairs of concentric electrodes electrically insulated
from each other and from the mounting pipeline while electrically
contacting a fluid in the pipeline being measured for flow rate.
The electrode pairs are held on the pipeline wall on a line intersecting
the fluid flow at a right angle and are electrically connected to
supply signals induced by the fluid flow to a measuring circuit.
The concentric electrode structure provides two electrode pairs
at each electrode site on the pipeline wall.
A flow-meter having a sliding lamina interposed between two chambers
and movable to vary the flow therethrough in response to deviations
in the pressure difference between the chambers to maintain a constant
preset pressure difference for accurate measurement of instantaneous
flow rates over a wide range. A cam surface relates linear variation
in flow rates to non-linear variation in the area of the opening
for fluid passage.