Page 1174 - The Mechatronics Handbook

FLUID FLOW
INPUT

PROXIMITY
SENSOR COUNTER
(a) OUTPUT

COUNTER
OUTPUT
PROXIMITY
SENSOR

PADDLE WHEEL
FLUID FLOW
INPUT

(b)

OUTPUT
ANGULAR VELOCITY
SENSOR

DRIVE GEAR
FLUID FLOW
INPUT

IDLER GEAR

(c)

FIGURE 45.10 Fluid power flowmeters: (a) turbine flowmeter, (b) paddle wheel flowmeter, (c) gear motor
flowmeter.

• Ultrasound (Fig. 45.11)
• Vortex shedding (Fig. 45.12)
• Thermal anemometer (Fig. 45.13)
• Electromagnetic (Fig. 45.14)
• Rotameter (variable-area in-line flowmeter) (Fig. 45.15)
Differential pressure flowmeters are suited to high- and moderate-velocity flow of gas and clean, low-
viscosity liquids. Venturi flowmeters [Fig. 45.9(a)] are the most accurate, but they are large and expensive.
Orifice flowmeters [Fig. 45.9(b)] are smaller, less expensive, and much less accurate than venturi flowmeters.

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