Bosch rexroth MBT, Руководство пользователя

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Fig. 10-15: Correlation between duty cycle and torque.
10.3.2 Determining the duty cycle
The approximate determination of the relative duty cycle ED
ideal
is performed
via the correlation:
ED
ideal
Cyclic duration factor in %
M
N
Continuous rated torque in Nm
M
max
Maximum torque in Nm
Fig. 10-16: Approximate determination of duty cycle ED
Prerequisites: Linear correlation between torque and current.
For MBT motors acc. to
Fig. 10-16 , only an approximate duty cycle calcula‐
tion is possible since there is a non-linear correlation between torque and
current.
To roughly determine potential duty cycles in case of short-time duty forces
with M
KB
≤ 1.5 M
N
, this calculation is valid.
For an exact determination of the relative duty cycle of the syn‐
chronous torque motors MBT, use Fig. 10-17 or Fig. 10-18 .
The non-linearity of the characteristic curve torque via current of synchronous
torque motors leads to an increased rise of power loss at higher torque
forces. This increased power loss leads - in particular at a high percentage of
acceleration and deceleration processes - to a possible duty cycle that is re‐
duced with respect to Fig. 10-16 .
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Motor dimensioning
MBT High Synchronous Torque Motors
Bosch Rexroth AG R911298798_Edition 08