Siemens SIMOTICS S-1FT7 - Axial Force Loading

Mechanical properties
3.7 Radial and axial forces
S-1FT7 synchronous motors
60 Configuration Manual, 09/2018, A5E45099423B AA
3.7.4
Axial force loading
When using, for example, helical toothed wheels as drive element, in addition to the radial
force, there is also an axial force on the motor bearings.
The axial forces can overcome the spring loading of the bearings so that the rotor is shifted
corresponding to the bearing axial play that exists.
Table 3- 14 Permissible axial rotor shift
Shaft height
Displacement
36 and 48
approx. 0.2 mm
63 to 132 approx. 0.35 mm
NOTICE
Motor damage as a result of bearings that are not pretensioned
Bearings that are not pretensioned can result in premature failure of the motor. An axial
force as large as the spring-loading is not permitted (100 ... 500 N).
• Comply with the permissible axial force.
Calculating the permissible axial force: F
A perm
= F
R
● 0.35
NOTICE
Motor damage caused by axial force for motors with integrated holding brake
It is not permissible for motors with integrated holding brake to be subject to axial forces.
• For motors with integrated holding brake ensure that no axial forces are applied to the
shaft extension.