Sewing Machine Looper

A sewing machine looper is an essential component of a serger or overlock machine, which is used for sewing and finishing fabric edges. The looper works in conjunction with the needles to create different types of stitches, such as overlock, rolled hem, and flatlock stitches.

The primary function of the looper is to form loops of thread that interlock with the needle thread, creating secure and flexible seams. Unlike a traditional sewing machine, which typically has one bobbin and one needle, a serger has two loopers: the upper looper and the lower looper.

Here's a general overview of how the sewing machine looper works:

Upper Looper: The upper looper carries a spool of thread that feeds the thread from above the fabric. The thread is guided through a series of thread guides, tension disks, and thread channels to reach the looper mechanism.

Lower Looper: The lower looper carries a spool of thread that feeds the thread from below the fabric. It also follows a similar path as the upper looper through thread guides, tension disks, and thread channels.

Loop Formation: As the fabric is fed through the serger, the needles penetrate the fabric and form a stitch. Simultaneously, the upper and lower loopers create loops of thread that pass around the edge of the fabric.

Interlocking: The upper and lower loops are then interlocked together between the layers of fabric, sandwiching the raw edges. This interlocking action creates a strong and secure seam.

Knife Trimming (optional): Some sergers also have a cutting knife positioned near the loopers. The knife trims the excess fabric along the edge as the loopers form the stitches. This feature helps achieve neat and finished edges.

Thread Tension: The tension disks and guides for both the upper and lower loopers ensure that the appropriate amount of tension is applied to the threads. Correct tension ensures balanced and even stitches.

By coordinating the movement of the loopers, needles, and fabric feed mechanism, the serger produces various stitch formations depending on the desired finish and stitch type.

It's worth noting that the specific mechanisms and functions of sewing machine loopers can vary among different serger models and manufacturers. Therefore, it's always recommended to consult the machine's manual for detailed instructions and guidance.