14
3.6.6 Top roller
3.6.6.1 Selection of the top roller diameter
The machine can be supplied with three types of top roller, namely with
the diameter of 25, 35 and 45 mm . The suitability of the diameter used
depends on the type of sewing and on the concrete technological
operation.
There are in general valid the following principles for the selection of
the wheel diameter:
smaller
ø
- for sewing small radii
higher
ø
- for sewing straight sections or big radii
- for sewing with great passages to thicker materials
3.6.6.2 Forward, rearward and side setting
The top roller must be in a defined position in relation to the needle:
a) view (see Fig. 1) - the value X depends on the diameter of use top
roller (
ø
25 - 8 mm;
ø
35 - 13 mm;
ø
45 - 18 mm), it is measured
from the the needle bar up to the roller edge when turning the
handwheel to the 180
°
of the scale against the indicator
b)view (see Fig. 2) - the wheel edge must fit with the edge of the needle
operture at the spot of the needle punch.
These values are to be set as follows:
Caution! Danger of injury!
Switch off the main switch! Before starting the setting
operation, wait until the motor stops!
- Loosen the screw (1).
- By shifting the holder (2) with the top roller (3) in the groove of the
holder (4) set the required value X and tighten the screw(1).
- Loosen the screw (5)
- By shifting the holder (2) in the holder (6) set the bottom edge of the
roller to the edge of the needle operture.
- Tighten the screw (5).
3.6.6.3 Setting the gear clearance
and in the mounting of the top roller
In the cone gear of the drive of the top roller foot, the minimum clearance
must be set. A too small clearance will increase the friction resistance
of the gear, the excessive clearance will influence the inaccuracy of
feeding. The top roller itself is mounted on balls. With this type of
mounting,it is also necessary to set the minimal possible radial
clearance.
The given clearances are set as follows:
Caution! Danger of injury!
Switch off the main switch! Before starting the setting
operation, wait until the motor stops!
Clearance in the wheel mounting
- Loosen three screws (5) /only slightly/.
- Using the screw (4) set the minimum clearance in the top roller
mounting (2) /it must easily rotate without any rubbing and with a
minimum clearance/.
- Tighten the screws (5), check the set up clearance, even-tually, repeat
the setting procedure.
Clearance in the conic gear
- Loosen the screw (1), in shifting the wheel, resp. the holder (3) in
the holder groove (6), set the minimum clearance, the pinion (7)
must be pushed up to the holder bottom (6).
- Tighten the screw (1), check the set up clearance.
Fig. 1
X
3
2
6
5
1
4
Fig. 2
4
3
1
2
7
5
6
