Page 159 - Fluid Power Engineering

Hydraulic Pumps 133

10 Gerotor
The inner rotor has one
less tooth than the outer
(internally toothed) element.
The rotor moves in a
planetary motion.
V = 50–350 cc
g
n = 500–2000 rpm
p = 100 bar
max
V = bz A ( − A )
g max min

11 Screw pump
The displacement chamber
is formed between the
threads and housing.
π
V = ( D − d s D 2
−
)
2
2
g
4
⎛α sin α ⎞
2
× ⎜ − ⎟ s
⎝ 2 2 ⎠
α
+
2
with cos(α)(= Dd )/ D
V = 2–1500 cc
g
n = 500–3500 rpm
p = 200 bar
max
12 Vane pump
(two strokes per revolution,
pressure balanced)
Volume is created between
the rotor, stator (cam ring),
and vanes.
V = 10–500 cc
g
n = 500–2500 rpm
p = 200 bar
max
V = (2 V − V ) z
g max min

(Continued)