7. FEEDING MECHANISMS AND SEWING MACHINE ATTACHMENTS
The fabric handling components of a sewing machine are called as the sewing machine feeding system. For producing a accurate straight line of stitches, the fabric must be moved through the stitch-forming area of the sewing machine precisely and accurately. The feeding mechanism of sewing machine controls movement of fabric during sewing. It normally consists of three components, namely, the presser foot, the throat plate, and the feed dog. Each of these components has many variations in shapes and sizes. Application of these appropriate of these components depends on the type of sewing machine, number of needles used, types of attachments used and types of operations (Araujo et.al 1992; Chmielowiec 1995; Carvalho et.al 2009).
7.1 Elements of feeding mechanism
7.1.1 Presser Feet The presser foot is the upper component of the feeding mechanism that grips the fabric in place during the feeding action and stitch formation. The presser foot, which is attached to the presser bar, controls the quantity of pressure applied on the fabric as it is fed through the sewing machine. The amount of pressure can be varied based on the sewing speed and fabric construction and weight. Higher sewing speeds may require more pressure to control the movement of fabric (Araujo et.al 1992; Chuter 1995). A basic presser foot could be assembled as a single unit or hinged to facilitate movement over bulky seams. The universal type is the