HappyJapan HCH-701-30, Maintenance Manual

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1 43
Trouble shooting(Upper thread comes off from needle hole)
7-2-5
Trouble Factor Cause of trouble and measure
Page
Upper thread
Mechanical
10.Check the needle bar moves when start sewing.
comes off 10-1 Adjust position to fix jump device. 3-2-5
from needle 10-2 Replace needle bar driver. 3-2-4
hole 11. Is number of revolution proper when sewing started? (25-2)
11-1 Make automatic speed setting. 4-3-5
12.Is height of pressure foot proper?
12-1 Adjust as specified.
3-2-10
Operator 1. Isn't thread tension too strong? (4-5) (8-1)
1-1 Weaken tension not to cause trouble in sewing rhythm.
2. Keen in cleaning thread cut device?
(23-3)
2-1 Clean bobbin thread holder regularly.
3. Is setting of bobbin thread proper?
(4-5)
3-1 Pass thread on bobbin thread guide surely.
4. Is bobbin thread properly wound?
(4-4) (4-5)
4-2 Pull out bobbin thread to check if it comes out smoothly.
5. Is upper thread properly passed?
(4-6) (4-7)
5-1 Pass properly again.
6. Does thread cone stand properly?
(4-6)
6-1 Keep thread from hitting felt.
6-2 Stand vertically.
7. Is [create] properly set?
(15-1)
7-1 Select longer setting of upper thread length.
7-3 Select start lock stitch [effective].
Thread & 1. Is thread used to suit embroidery? (thread twist, tender thread).
3-1-3
Cloth 1-1 Don't use too strongly twisted thread.
1-2 Twist of thread is to be left-wise.
1-3 Use tender thread.
1-4 Don't use thread with knot or uneven size.
Environment
1. Does wind let thread go beyond control? (outside wind, heater, and fan etc.) (2-6)
1-1 Keep the embroidery machine off from wind.
2. Is voltage of power as rated and stable?
2-1 Supply rated voltage.
Pattern 1. Is there stop sewing stitch for start sewing?
1-1 Modify pattern. 1-2 Set lock stitch function. (15-5)