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2.11 Background Information about Control Technology
2.11 Background Information about
Control Technology
Adapted motor support with hub gear
system
X Motor support acts directly on the chain wheel and
is not constant, but rather modulates up and down
just like the pedalling power with a conventional
bicycle.
X For eBikes with hub gear systems, the motor sup-
port is reduced significantly with every rotation of
the pedals to facilitate gear changes.
X Benefits: The modified torque progression
protects
the mechanical components and facilitates engage
-
ment of the selected gear.
Gear shift detection during derailleur gear
shifting
X During gear shifting, the motor torque is reduced at
exactly the right moment and then increased again.
– The chain pull is reduced during the gear shift.
– The drive control detects this interruption and
briefly reduces the motor support.
X Benefits:
Smoother gear shifting and significantly
reduc
ed chain noise during gear shift to a higher
gear
Motor support in Nm
Time (of the represented period is for approx. one
crankshaft rotation)
Progression of motor support
Reduced motor support to facilitate gear shifting
M =
t =
M
0
t
Motor support in Nm
Time (of the represented period is for approx. one
crankshaft rotation)
Motor support characteristic with derailleur gear system
Motor support characteristic with hub gear system
Time window for gear change with hub gear system
M =
t =
M
0 t
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