Technical data

MKE UL/CSA Notes Regarding Application 12-9
DOK-MOTOR*-MKE*UL/CSA*-PR01-EN-P
Note:
· Thermal effects can shift the flanged end of the drive shaft to the
motor housing by up to 0.6 mm. If helical toothed drive pinions or bevel
gear pinions are used and mounted directly to the output shaft, then
these changes in the length can lead to the shifting of position of the
axis, if the drive pinions are not axially fixed to the machine, or.
· a thermally dependent component of the axial force if the driving
pinions are axially fixed fastened on the machine side. There is the
danger, in this case, that the maximum permissible axial force can be
exceeded, or that the clearance within the toothing is unacceptably
increased.
The use of drive elements with bearings which are connected
to the motor shaft via an axial compensating coupling is
therefore recommended
Bearing lifespan
If MKE motors are operated within the stated limits for radial and axial
loads, the nominal bearing life span is:
L
10h
= 30,000 operating hours
(calculated per ISO 281, Edition 12/1990)
Bearing lifespan otherwise drops to:
30000
F
F
h10L
3
ist_radial
radial
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×
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ø
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L
10h
: bearing lifespan (according to ISO 281, Edition 12/1990)
F
radial
: determined permissible radial force in N (Newtons)
F
radial_act
: actual effective radial force in N (Newtons)
Fig. 12-12: Calculation of the bearing lifespan L
10h
if the permissible radial force
F
radial
is exceeded
Note: The actually effective radial force F
radial_act
may at no time
exceed maximum permissible radial force F
radial_max
.
Mounting drive elements
When mounting drive elements to the motor shaft, do not use fixed
supported bearings, but rather bearings that are simply supported. The
unchanging tolerances generate additional forces to the bearings of the
motor shaft and may lead to a significantly drop in service life of the
bearing.
Note: If a fixed type of mounting cannot be avoided, please contact
Rexroth Indramat before you proceed.
bearing lifespan
Mounting drive elements