3.3
Adjusting the belt tension
1
Caution: Danger of injury !
Switch the main switch off.
Adjust the belt tension only with the sewing unit switched off.
Correction
–
Push the transport carriage to the front.
–
Measure the distance between the toothed belt and the upper edge
of the table top with a tape measure 1.
–
Pull the toothed belt down with a spring balance 2 and a power of
20 N.
–
The toothed belt tension is correct when the distance between the
toothed belt and the upper edge of the table top can be reduced by
11 mm at 20 N (Example: 170 - 11 = 159 mm).
Consequences of a too high toothed belt tension
–
Reduced durability
–
Noisy running
Consequences of a too low toothed belt tension
–
No faultless meshing between belt teeth and disc toothing
–
The teeth may skip over under load
–
Non-uniform stitch lengths
–
Loss of steps possible
2
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