Flat Singlebed Warp Knitting Machines with Spring Beard Needles

The components operating during the stitch formation cycle on flat single-bed warp knitting machines with spring beard needles are the following: the needles - the guide bars - the sinkers - the presser.

Picture 131 shows the various steps of the stitch formation cycle and the diagram of the machine movements, which shows the paths of the various components operating during a single revolution of the driving shaft.

  1. The needle is in its knock-over position and starts rising; the sinker approaches and holds the stitch in the throat; the guide, initially positioned behind the needle, starts moving.
  2. The needle reaches its relative maximum height and stops to let the guide pass and position in front of the needle.

With the needle in its standstill position, the thread is fed and laid over the needle stop; the sinker withdraws slightly to reduce the thread tension during the feeding step.

  1. Since the feeding operation has been carried out above the spring beard of the needle, the needle rises further and reaches its absolute maximum height to let the thread slip on the stem; in the meantime the guide returns behind the needle while the sinker is approaching the needle.
  2. The needle starts lowering and the thread enters the hook; at this point the presser closes the needle hook, which is now in its standstill position.
  3. Now the previous stitch, which is still on the needle stem, must be knocked over on the next thread.

The needle cannot lower since it is still touching the presser; therefore the sinker is withdrawn so that the stitch in the throat can move upwards along the slant section of the throat and above the hook.

6. The presser withdraws and the needle starts lowering again; the stitch moves above the hook and once the needle has reached its bottom position, it knocks over on the next yarn, thus creating a new stitch. In the meantime the sinker has withdrawn and now holds the fabric with its breast.

The guide can now move sidewise for the floating movement.

Stitch Formation Cycle Knitting
Picture 131 - Stitch formation cycle on a flat single-bed warp knitting machine equipped with spring beard needles
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