Installation
Design Guidelines
«EC frameless DT» Installation Manual
mmag | 2021-12 | rel10341
3-15
3.2.5
Bearing and Fixation of the Rotor
maxon recommends the use of ball bearings with an ISO tolerance class P5 or higher.
maxon recommends to join the rotor of the «EC frameless DT» and the customer’s counterpart (shaft) by
adhesive bonding. It is important to ensure that the bonded joint is designed that the maximum motor torque
can be transmitted with a sufficient safety margin over the entire operating range.
Possible irreversible damage of motor
The rotor is not designed to produce a force-fit torque transmission to the customer shaft by means of a
press fit (interference fit, shrink fit).
maxon explicitly advises against a press fit.
The following data are to be understood as recommendations. They apply to common models and methods
under typical conditions and do not claim to be complete or correct. For manufacturers and sources of sup-
ply see
Table 3-7
Fixation of the rotor – recommended adhesives
3.2.6
Fixation of the Stator
maxon recommends to fix the stator of the «EC frameless DT» axially using bolted connections. This axial
screw connection also serves as a non-positive transmission of the torque.
Requirements for operation
Use only screws that, once installed, do not protrude the inside front face of the stator flange. Too long
screws can damage the printed circuit board, thus possibly causing electrical breakdown and destruction of
the motor.
The following data are to be understood as recommendations. They provide an overview of the recom-
mended fastening screws and the minimum tightening torques for safe torque transmission. An application-
specific screw calculation as to VDI guideline 2230 must be taken into account.
The screw connections must be tightened to the appropriate torque using a torque wrench.
Table 3-8
Fixation of the stator – recommended bolted joints
The screw connections must locked and secured using threadlocker or Nord-Lock safety washers. For man-
ufacturers and sources of supply see
Continued on next page.
Drive
Shaft material
Adhesive
Shaft
tolerance
Surface finish
EC frameless DT50M
Steel
Ergo 4430
DELO-ML 5327
27.96 mm
±0.01
≤
R
a
1.6
Drive
Screws
Property class
Tightening
torque
EC frameless DT50M
4ea M4
min A2-70 / 6.8
2 Nm
