An apparatus is provided for measuring the amount of fluid (21) flowing in
a channel (18, 20). The apparatus comprises a fluidic oscillation flow
meter (10) including a housing (14) defining an inlet (16) for receiving
the fluid (21), and first and second diversion channels (18, 20) for
alternately receiving the fluid (21) from the inlet (16). The housing
(14) comprises a first nozzle (46) for receiving the fluid (21) from the
first diversion channel (18) and deflecting the fluid (21) from the inlet
(16) into the second diversion channel (20). A second nozzle (48)
receives the fluid (21) from the second diversion channel (20) and
alternately deflects the fluid (21) from the inlet (16) into the first
diversion channel (18). A first layer of material (56) overlies at least
one of the first and second diversion channels (18, 20) and includes a
sensing area that distorts due to a pressure change caused by the fluid
(21) flowing through the diversion channels (18, 20). A first sensing
piezoresistor (62) is positioned on the layer of material (56) near the
first diversion channel (18) for detecting the pressure change of the
sensing area and generating a frequency signal.