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10.
Maintenance
Caution! Danger of injury!
The maintenance operations should be performed only with the machine switched off and with the motor stopped!
In the following table there are given the operations which should be performed and the respective time intervals between the
individual operations.
11. Setting the machine according to the sewing category
11.1 Introduction
This sewing machine enables sewing operations within a large extent from the light up to the heavy-duty sewing. The parameters
of the respective sewing operation must be in accordance with the given machine setting which includes also the replacement
of some components, such as the needle, the throat plate insert, the spring of the main tensioner, the top roller. For this reason,
the setting of the machine is divided into 4 categories:
1 ... light sewing
2 ... medium sewing
3 ... medium heavy-duty sewing
4 ... heavy-duty sewing
In the factory, where this machine has been manufactured, the machine has been set with respect to the standard parameters of
the required sewing category which is designed by the number included in the commercial designation of the machine. If the user
desires changing the given setting to another sewing category, this operation should be performed by a specialized mechanician.
Caution!
When changing the sewing category, loosen the tensing up of the fixed trimming knife.
Otherwise there is a danger of destruction of the moving knife.
The standard parameters of sewing are described in the following paragraph. The actual parameters of sewing inside the given
sewing category may be different, which means that the machine operative must adapt respectively the setting of the machine,
e.g. the tension of the upper thread.
Operation
Time interval
Removal of the throat plate and its cleaning out. Cleaning out of the feeder, hook and their
surrounding space. Removal of the residues of material and threads from the top roller.
1 day
Checking the oil level in oil reservoir.
1 month
Checking the hook wear. Checking the function of the safety clutch against the hook overload.
6 months
Checking the V-belt and the indented belts, checking the friction wheels of the drive convertion unit.
1 year