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4.7 Setting the retaining spring of the hook thread
The retaining spring (1) holds the hook thread after having
performed the trimming. It is to be set in such a way that the
force necessary for pulling out the thread from the retaining
spring (1) is approximately equal to the force necessary for
pulling out the thread from the hook.
Caution! Danger of injury!
Switch off the main switch! Before starting the
setting operation, wait until the motor stops!
- Shape the retaining spring (1) in such a way that it fits close
with all its surface (without wedge) onto the moving trim-
ming knife (4).
- Shape the retaining spring in such a way that with mode-
rately tightened screws (2) it comes to lean against the
moving trimmer knife with a pre-load corresponding to the
force required to draw the thread out of the spring.
The pulling force is tested using a screwdriver according to
the illustration.
Caution!
The setting of the retaining spring (1) depends
on the setting of the hook tension and differs
then according to the respective sewing category.
4.8 Setting the switching of electromagnets
The electromagnets of the trimming device and loosening of
the
tensioner must work in accordance with the diagram. This is
ensured by setting the stopmotor (see the instructions for
use of
the stopmotor).
1- 1. position of the needle (135
°
on the handwheel)
2- 2. position of the needle (64
°
on the handwheel)
3- position of stopping the tensioner (10
°
÷ 25
°
on the hand-
wheel)
4- movement of the pickup roller
5- current of the trimming device electromagnet
6- current of the tensioner loosening electromagnet
5
.
Lifting the top roller by electromagnet
5.1 Description
The core of the electromagnet, respectively its pin must be set
in such a way that the presser foot lifting is enabled.
5.2 Setting the electromagnet pin
Caution! Danger of injury!
Switch off the main switch! Before starting the
setting operation, wait until the motor stops!
- Unscrew the cap of the core (1) of the electromagnet.
- Shift the core (2) with the bar (3) and loosen the locking
screw (4).
- By screwing the pin (3) in the core (4), set their mutual
position in such a way that the core is fully pushed in with
the maximum presser foot lift.
- Tighten the locking screw (4).
- Screw on the cap (1).
4
5
6
1
3
2
2
4
1
3
1
4
2