Brother b831 - Sewing Machine Mechanisms; Upper Shaft and Needle Bar Mechanism; Needle Feed Mechanism

mm
When pulley O turns inthearrowdirection, its rotating motion is conveyed touppershaftO toturncounterweightO-
The motion is conveyed to needlebarcrankrod 0via needlebarcrankO which isconnectedtocounterweight©.The
shape of arc motion is conveyed to the thread hole in thread take-up lever ©via thread take-up lever slide block O
which IS connected to needle bar crank rod 0.
Needle bar O moves up and down via needle bar clamp 0 which is connected to needle bar crank rod 0.
Needle bar O is guided by needle bar support O
(The arc motion is conveyed to the thread hole in thread take-up lever © via thread take-up leverslide block ©which is
connected to needle bar crank rod 0).
U] NEEDLE FEED MECHANISM
\W o
When pulleyO turns inthe arrowdirection, its rotating motionis conveyed to upper shaft O to turn timingbeltwheel
upper 0.
The motion is conveyed to timing belt wheel lower 0 via timing belt ©.
Eccentric wheel O which is connected to lower shaft 0 rotates via timing belt wheel lower 0 and lower shaft ©.
Level feed arm © moves in the shape of arc via eccentric wheel O. level feed connecting rod O and level feed
connecting link 0
The motion is conveyed to needle bar rock crank ® via feed rock shaft o
Needle bar support © moves back and forth via needle bar rock link © and needle bar connecting rod ©.
Needle bar © which is connected to needle bar support © moves back and forth.