Brother LH4-B800E Service Manual download pdf (Page 123)

LH4-B800E

5 - 8

5. Troubleshooting guide

Cause Check Solution page

Upper thread

trimmer

assembly

Upper thread trimmer

assembly position

Move the setting plate

assembly to adjust the

scissors assembly

setting position.

(Upper thread scissors

longitudinal position

adjustment)

Upper thread scissors

cutting depth

adjustment

4-14

4-15

Operating pressure of

upper thread trimmer

assembly

Correct operating

pressure by upper

thread upper trimmer

Adjust the operating pressure as

follows; After thread trimming, pick

the pinched thread and shake lightly

Check that the thread does not take

off upper thread trimmer assembly

-

Upper thread trimmer

driving spring

Change if transformed

Tension

release

timing

End of tension release

at the beginning of

sewing

Retard the tension

release timing

Change using parameter No. 63 -

(Instruction)

Opening amount of

zigzag tension discs

and bar tack tension

discs

Adjust the release

dimension

Adjust the zigzag tension discs by

moving the tension stud bracket in

and out.

Adjust the bar tack tension disc

opening amount to 0.5 -- 1 mm by

removing the top cover and moving

the tension release cam.

4-25

Upper thread

feeding

Needle thread take-up Increase needle thread

take-up

Increase thread take up to a degree

that needle thread does not take off

upper thread trimmer assembly

4-26

5-8. Needle thread runout

Zigzag tension

Tack tension

Screw

Less

More

Cotton yarn #60

Holding force approx. 2 N

1 2 ... 118 119 120 121 122 123 124 125 126 127 128 ... 167 168

Comments to this Manuals

No comments