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Festo 7EGC_TB_KFb_en
Note
Block-shaped acceleration profiles (without smoothing) cause high peaks in the motive force that can lead to over
-
loading of the drive. Positions outside of the permissible range can also occur.
A smoothed acceleration specification reduces vibrations in the entire system and has a positive effect on the stresses
and strains to which the mechanical system is subjected.
• Check which closed-loop controller settings can be adapted (e.g. jerk limitation, smoothing of the acceleration profile).
4.3.1
Renewing the roller carriages
Note
Festo recommends, as a basic principle, that you always replace the entire drive if a defect occurs in the linear recircu-
lating ball bearing guide system.
Replacement of the roller carriages is undertaken by users at their own risk.
In the case of the EGC-50, only the complete module comprising the slide and roller carriages can be replaced.
Note
Before replacing the roller carriages, check the guide rail for wear and damage. Defective or worn guide rails cannot be
replaced. It is the responsibility of the users to assess the wear and damage to the guide rail.
The roller carriages can only be renewed with axes below a specific stroke length (see table).
Type
Maximum stroke length incl. 2 × stroke reserve
EGC-50-GK
No restriction
EGC-70-GK/GP
≤ 3,469 mm
EGC-70-GV/GQ
≤ 3,369 mm
EGC-80-GK/GP
≤ 4,644 mm
EGC-80-GV/GQ
≤ 4,544 mm
EGC-120-GK/GP
≤ 5,754 mm
EGC-120-GV/GQ
≤ 5,654 mm
EGC-185-GK
≤ 5,668 mm
EGC-185-GV
≤ 5,568 mm
In the case of toothed belt axes with longer strokes, the roller carriages and the guide rail are paired. This means that
the guide system cannot be repaired and the toothed belt axis must be renewed in these cases (see section
4.3 “Linear
recirculating ball bearing guide system”
). These toothed belt axes cannot be subsequently retrofitted with additional
slides for the same reason.
Note
In emergency situations (e.g. when the machine is stopped), the roller carriages on toothed belt axes with longer
strokes can be swapped for standard roller carriages at the user's own risk.
The specified operating clearance
between the roller carriage and guide rail is then, however, no longer guaranteed.
This can result in increased pre-
tension or increased guide backlash, which reduces the service life.
Renewing the roller carriages calls for the removal of a drive cover. To do this, carry out the steps described in section
4.2.1 “Removing the drive covers”
.
