Bosch rexroth MCL, Project Planning Manual

Page: 157 / 206

11.3 Duty cycle and feed force
11.3.1 General
The relative duty cycle ED specifies the duty cycle percentage of the load
with respect to a total duty cycle time, including idle time. The thermal load
capacity of the motor limits the duty cycle. Loading the motor with a continu‐
ous nominal force is possible during the entire duty cycle time. To avoid ther‐
mal overload at motors with higher feed forces reduce the duty cycle at F >
F
dN
(see fig. 11-20 "Correlation between duty cycle and feed force." on page
149 ).
Fig. 11-20: Correlation between duty cycle and feed force.
11.3.2 Determining the duty cycle
Due to the linear correlation of force and current, the approximate determina‐
tion of the relative duty cycle ED
ideal
is performed via the correlation:
ED
ideal
Cyclic duration factor in %
F
EFF
Effective force or continuous force in N
F
MAX
Maximum feed force
Fig. 11-21: Approximate determination of duty cycle ED
Determination of possible relative duty cycle can done with the help of fig.
11-22 "Determining the duty cycle ED" on page 150 .
MCL Ironless Linear Motors 149/197
Motor dimensioning
R911330592_Edition 06 Bosch Rexroth AG