Brother International EF4-B561 Service Manual - Page 12

DOUBLE CHAIN STITCH LOOPER MECHANISM OO O 0 OO Os OO O0 12 Id 1) Double chain stitch looper back and forth movement mechanism In case that crank shaft may rotate to the direction indicated with arrow, with longitudinal eccentric cam 0, longitudinal feed driving rod 0 moves up and down. IC Longitudinal feed lever slide borck 1:5 with longitudinal feed lever is fitted into the top end of longitudinal feed driving rod 0 and gets back and forth movement making longitudinal feed lever shaft Q as a fulcrum. Longitudinal feed lever slide block 0 connected between thrust collar 0 upon longitudinal feed shaft 0 and set collar 0, it carrys to double chain stitch looper 41 with the intermediate action of longitudinal feed shaft 0 and double chain stitch looper holder m . 2) Double chain stitch oscillating mechanism ® , • Chain stitch driving lever 0 is conveyed the oscillating motion by under looper connecting lever with the intermediate action of under looper connecting lever pin chain stitch link and chain stitch driving lever pin Its oscillation motion is conveyed to longitudinal feed shaft 0, double chain stitch looper holder m and double chain stitch looper KNIVES MECHANISM Os 1) Upper knife mechanism • In case that crank shaft 0 may rotate to the direction indicated with arrow, with needle bar and upper knife eccentric cam 0, upper knife driving rod 4) moves up and down. -10-