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!"""# ! $%# &'( ) ( *'+,,%-,.'/+- &/.+/,,%-,.'/+- Function: • " 0! • "12 • ') ! • 3"#! ,,%4, Types: % %# '( / & %5,,%-,.'/+- [...]... of feed dog teeth & fabric at the same place NEEDLE FEED NEEDLE FEED • Needle feed is the feed system in which the needle itself moves forwards and backwards • The needle enters the fabric, moves back with it as it is moved along to begin the next stitch • It is particularly useful in bulky sewing situations such as when quilting through the fabric and wadding 2-needle, Needle -feed, Lockstitch Machine. .. carpet etc NEEDLE FEED • On the needle feed, the needle moves to and from as well as up and down • The other is a normal machine in which the needle only moves up and down • Needle feed mechanisms are good at preventing the layers of material from slipping, which can be especially important for slick fabrics • Since some needle feed mechanisms do not put pressure on the fabric the way feed dogs do, they... they will not leave any marks on delicate fabric NEEDLE FEED The three main types of needle feed mechanisms are • • • the upper pivot, the central pivot and the parallel drive Pivoting needle feed mechanisms move the needle at an angle to help feed the material through the machine, while parallel drives only move the needle back and forth NEEDLE FEED- UPPER PIVOT • The needle bar, which carries the... type of needle feed suitable for stitching the heaviest and thickest of materials The mechanism involved in a parallel drive makes for a more expensive unit and will generally have a slower stitching speed WHEEL FEED WHEEL FEED • A rotary wheel with a movement in the direction of feed • Incorporates a friction surface or clamping surface that feeds or assists in feeding the goods WHEEL FEED • Has either... a continuous motion • Continuous motion wheel feed must work in unison with a needle feed • Applicable to all types of sports shoes, shoes, children shoes, boots and other footwear and handbags sewing UPPER AND LOWER WHEEL FEED • Wheel feed system where an upper and lower wheel are both driven • The material is fed between the wheels • There is positive feeding pressure both the top and bottom of the... WHEEL FEED UPPER AND LOWER WHEEL FEED ROTARY WHEEL FEED • Mechanical foot or bit, with teeth or friction surface or a smooth surface, that transports or assists in the transport of material Often a foot working in unison with a drop feed • Has a directional movement in which the material is fed ROTARY WHEEL FEED • May push downwards into the material to capture material between itself and another feed. .. OF DROP FEED • • When two plies fabrics are sewn- lower ply moves forward by the help of feed dog but foot So two plies of fabric can not move forward at the same speed As a result lower ply is more fed than upper ply • • • This is called ply shifting/differential feeding pucker/feeding pucker Sometimes roping is occurred during making of hem for ply shifting It pitch of stitch s pitch of feeding dog... practice it does not, except with thicker or heavier goods • There is less momentum of the needle bar frame in motion than with the upper pivot system, and higher stitching speeds can be reached NEEDLE FEED- THE PARALLEL DRIVE • The needle bar, which carries the needle, is held in a frame, and its motion is always parallel in relation to its prior and successive movements • It remains perpendicular to... • In other words, the needle enters the goods at a certain angle and exits at a different angle • This would seem to disrupt the material and the stitching process, but in practice it does not NEEDLE FEED- CENTRAL PIVOT • The needle bar, which carries the needle, is held in a frame, and its motion is pivoted from a point near the middle of the frame • The needle will enter the goods at a greater leading... which the material is fed ROTARY WHEEL FEED • May push downwards into the material to capture material between itself and another feed component or against the bed or a plate on the bed ROTARY WHEEL FEED