Looper thread paying-out apparatus for sewing machine

A thread paying-out apparatus in a sewing machine for feeding a thread from a bobbin through a thread tensioner into a seam forming means, said apparatus comprising an auxiliary paying-out device arranged upstream of said thread tensioner for paying out a portion of thread for a length of one stitch corresponding to stitching movement of said seam forming means;

• said auxiliary paying-out device including an auxiliary thread take-up pivotably mounted on a feed rock shaft for driving a horizontal cloth feed mechanism and a thread guide for drawing out and accumulating said length of one stitch just before a thread is drawn out through said thread tensioner toward said seam forming means by cooperating with the free end of said auxiliary thread take-up wherein said auxiliary paying-out device is located near a free end of said auxiliary take-up.

A sewing machine comprising a source of thread which is moved along a thread feed path during operation of said sewing machine, a looper which engages the thread and is movable through stitching strokes during operation of the sewing machine, said looper being operable to pull thread along at least a portion of the thread feed path during each of the stitching strokes of said looper, a thread tensioner disposed in engagement with the thread at a location along the thread feed path between said looper and said source of thread, and a thread paying-out apparatus disposed in engagement with the thread at a location along the thread feed path between said source of thread and said thread tensioner, said thread paying-out apparatus being operable to pull thread from the source of thread between each stitching stroke of said looper to minimize tension in the thread disposed along the thread feed path between said thread paying-out apparatus and said thread tensioner during movement of said looper through a stitching stroke.