Hikari H9199, Инструкция по эксплуатации и каталог запасных частей

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INSTRUCTION MANUAL
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Problem Possible cause Page
5
Skipped stitches at sewing
start
Thread unraveling at sewing
start
· Is the thread take-up spring tension too strong
？
Reduce the tension of the thread take-up spring. 。
· Is the thread take-up spring operating range too large
？
Lower the position of the thread take-up spring.
· After the trailing lengths of the upper threads too short after thread
trimming ？
Adjust the pretension.
· Are the thread not being trimmed cleanly ？
Sharpen the fixed knives, or replace the fixed and movable
knives if necessary.
· Is the needle too wide
？
Try using a needle with a count that is one lower than the current
needle.
· Is the length of thread trailing out from tee bobbin case after thread
trimming too short
？
If the bobbin is spinning loosely, replace the anti-spin spring in
the bobbin case.
。
·
Is the sewing speed too fast at the sewing start
？
Use the slow start feature.
·
Is the needle up stop position too high
？
Adjust the needle up stop position.
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6
Uneven seam
· Is the presser foot pressure too weak
？
Adjust the presser foot pressure.
· Is the feed dog too low
？
Adjust the feed dog height.
· Is the bobbin scratched
？
If the bobbin is damaged, smooth it with an oiled grindstone
or replace it.
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7
Large degree of puckering
(excess tension)
· Is the upper thread tension too strong
？
Make the upper thread tension as weak as possible.
· Is the lower thread tension too strong
？
Make the lower thread tension as weak as possible.
·
Is the needle tip blunt
？
Replace the needle if it is blunt.
·
Is the needle too thick
？
Replace with as thin a needle as possible.
· Are the thread take-up spring tensions too strong
？
Make the thread take-up spring tension as weak as possible. 。
· Is the thread take-up spring operating range too large
？
Lower the position of the thread take-up spring to as low a
position as possible.
· Is the presser foot pressure too strong ？
Adjust the presser foot pressure.
·
Is the sewing speed too fast
？
Use the sewing speed control keys to gradually reduce the sewing
speed.
· Is the angle of the feed dog correct
？
Tilt the front of the feed dog down slightly 。
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8
Material slippage · Is the presser foot pressure too strong ？
Adjust the presser foot pressure.
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