Technical data

9-20 Notes Regarding Application Rexroth IndraDyn H
DOK-MOTOR*-MBS-H******-PR02-EN-P
Rotor with Step Interference Fit
ring for balancing
oil chamber
ring for balancing
pressure oil
junction
(closed)
step
interference
O-ring
permanent-
magnets
øD2 øD1
pressure oil
for demounting
F
axial
spindle
step
interference
demounted rotor
mounted rotor
ROTEINBAU_2N_EN.EPS
Fig. 9-33: Rotor installation and functional principle of step interference fit
The rotor consists of a steel sleeve with permanent magnets on the
inside. The spindle has two fitting surfaces arranged next to each other;
these have slightly graduated diameters (
ØD1 > ØD2). The rotor and
spindle are frictionally engaged by the step interference fit. The
graduated fitting surfaces align the mounted rotor to the spindle; they are
required so that the rotor can be removed without damage.
The spindle construction in the area of the step interference fit must
correspond to the information in the dimension sheets of the
corresponding motor in chapter 5.
The rotor is attached by shrink-fitting it onto the spindle; the oil-pressure
procedure is used during removal.
Due to the required interference fit, the rotor sleeve must be heated up
to 135°C – max. 145°C before assembly. Due to material expansion, the
fittings expand to fit diameters D1 and D2.
CAUTION
Damage to the magnets in the rotor due to
temperatures over 145°C!
⇒ Heating the rotor sleeve must be monitored
⇒ Heating the rotor sleeve above 145°C is not
permitted.
At the same time, the spindle must be cooled to –20°C.
The rotor and the spindle can then be joined without force.
Oil under pressure is injected into the step interference fit during
removal. This creates an axial force with which the rotor can slide off the
spindle as soon as there is an oil film between the fitting surfaces to
Assembly
Dismantling