1. Height positioning of the needle:
When the needle rises to the highest point, the needle tip reaches the plane of the needle plate (2-thread, 3-thread 9-10 mm), (4-thread left needle is 9-10 mm, right needle is 8-9 mm), (5 The thread chain thread needle is 7.5-5.8 mm, and the hemming needle is 9-10 mm).
2. The positioning of the needle, the lower looper and the chain hook:
When the lower looper and the chain hook swing to the leftmost position, the distance from the tip of the lower looper to the needle when the needle is at its lowest point (3.5-4 mm for 3 threads), (4 threads 2.8-3.1 mm left needle) (5 threads 3.5-4 mm), the inclination angle of the looper is 3-6 degrees, and the gap between them is 0.05 mm; the distance from the tip of the 5-thread chain hook to the needle is 2.5-3 mm, and the hook angle is 5 -7 degrees.
3. Positioning of the needle, the upper looper and the upper needle
When the upper looper and the upper needle sliding bar reach the highest position, (the distance from the needle on the 2nd thread to the needle is 4-4.5 mm), (the needle tip of the 3rd thread machine goes down and contacts the upper looper when the tip of the upper looper reaches the machine The distance between the needles is 4-4.5 mm), (the needle hole of the looper on the 4th line is in the middle of the two needles), (the 5th line is the same as the 3rd line), and the distance between the upper looper and the lower looper is evenly 0.10 mm.
Strictly speaking, the alignment between the needle of the overlock sewing machine and the upper and lower loopers has requirements. For example, if the machine parts are loose or different sewing materials, it must be dealt with according to the actual situation of the machine.
