Fundamentals of Textile Design 3(2+1)

Lesson 20: Weft Knitting

Stitch formation with latch needles

The needles run in the cams as shown below. The butt of the needle is moved in the gap of the cam at different stages, where the old loop is cleared and the new loop is formed. The sinker holds the loops formed so that they do not rise along, when the needle is moving up.

The latch opens when the needle butt passes up the incline of the clearing cam, at the same time the old loop, which is held down by the sinker, slides down the hook and contacts the latch, opening it. When the needle reaches the top of the cam, the old loop is cleared from the latch, stays on to the stem

Yarn feeding and latch closing takes place when the needle starts to descend the stitch cam with the old loop moving under it. At this point the new yarn is fed to the descending needle hook. The old loop contacts the underside of the latch, causing it to close on to the hook. As the head of the needle descends, the old loop slides off the needle and the new loop are drawn through it.