Brother b831 Service Manual page 57

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1 ,
A
[1] WALKING BAR O
5.
6.
7.
8.
9.
10.
Needle
Feed dog
Walking bar
^ Presser bar lifter presser bar
Fit the walking bar rocker shaft 0 into the arm.
Fit the walking bar eccentric crank O onto the walking bar shaft 0. and tighten the set screw O so the crank is firm.
Mount the bell crank 0 on the walking bar shaft 0
Fit the walking bar link 0 on the bell crank 0.
(Fit the walking bar presser foot link 0 and bell crank 0 to three points: the bell crank link 0 hole, walking bar presser
bar. and presser bar lifter.)
Secure the bell crank roller 0 firmly to the bell crank 0.
Secure the feed lifting rocker shaft 0 with screw 0.
Secure the lifting presser foot guide 0 with screw 0
Fit the wick on the walking bar support link 0.
Replace the hinge screw ©, walking bar eccentric crank 0. washer 0. lock washer 0 and wing nut 0.
• Screw the wing nut © tight at the center of the walking bar eccentric crank 0 groove.
Secure the lifting presser foot 0 with screw 0.
6B Lifting and Vibrating Presser Foot Vertical Timing Adjustment
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2.
3.
4.
(1)
(2)
Loosen wing nut 0. and retighten at the center of the walking bar eccentric crank 0.
Loosen bolt 0.
Set the outer presser foot 0 and inner presser foot 0 to the needle plate 0.
Turnthe machine pulleyso that the thread take-up crank © is horizontal, as shown in the figure above. Make sure the
outer presser foot 0 and inner presser foot 0 are tight to the needle plate 0. and then tighten bolt O.
Make sure there is no play in the walking bar shaft 0.
Adjust the lifting and vibrating presser feet to the same height.
Lower the lifting and vibrating presser feet to the needle plate.
Move the needle bar crank 0 on the thread take-up crank 0 to the right, and firmly tighten the set screw ©.
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