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3.6.6 Setting the feeding difference
The size of feeding by the driven top roller is regulated by means
of a regulating screw. The top roller feeding is to be set in cases,
when a difference between the size of the top and bottom feeding
of the sewn material is evident. This will show up in upward or
downward bending of the sewn parts. It is therefore necessary,
when bending the sewn parts:
1. upwards - to increase the feeding performance of the top roller.
2. downwards - to reduce the feeding performance of the top roller.
This setting operation is done as follows:
- Loosen the locking nut (1) of the adjusting screw (2).
- Turn the screw to the left (in increasing so the feeding perfor-
mance of the top roller) or to the right (in reducing so the feeding
performance of the top roller).
- Test the result of this setting in sewing.
- Tighten the locking nut (1).
- The standard setting for the zero difference is 3 mm (see Fig.)
- the gap between the front faces of the screw (2) and the
nut (1).
3.6.7 Replacement of friction wheels of the drive
conversion unit
The worn friction wheels (1 and 2) of the drive conversion unit are
to be replaced. This is done as follows:
Caution! Danger of injury!
Switch off the main switch! Before starting the setting
operation, wait until the motor stops!
- Remove the front guard.
- Loosen and unscrew the screw (3) from the holder of the wheel
(4) and remove it from the holder (5).
- Loosen the screws (6 and 7) of the holder (8) and remove the
holder (8) with the telescopic shaft (9) and the driven wheel
from the machine.
- In pulling it out, remove the telescopic shaft (9) from the holder
(8).
- Loosen and unscrew the screw (10) and remove the shaft (11)
with the friction wheel (12) from the telescopic shaft.
- Press out the pin (13) from the shaft (11) and the wheel (12).
- Replace the wheel (12) by a new one and proceed to a reassembly
(an inverse procedure to the dismantling).
- Loosen the screw (14) of the conic friction wheel (15).
- Remove the wheel (15) and replace it.
- Proceed to a reassembly (an inverse procedure to dismantling).
2
1
3
9
7
10
8
6
3
5
11
14
15
13
12
4