Wyniki wyszukiwania - BazTech

Ograniczanie wyników

2 Autex Research Journal

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Effect of thread structure on tension peaks during lock stitch sewing

Rengasamy R. S., Wesley D. S.

Autex Research Journal

2011

Vol. 11, no. 1

1--5

A dynamic sewing tension study was carried out with a tension probe on sewing threads with different structures, physical and tensile characteristics in a single needle lock stitch sewing machine. The needle thread recorded four major tension peaks corresponding to events occurring during sewing; bobbin thread withdrawal, stitch tightening, needle piercing the fabric and tightening of the needle thread around the shuttle, among which stitch tightening caused the maximum tension for all threads. Polyester filament and spun polyester threads exhibited the highest and lowest tightening tension, respectively . Multiple regression analysis showed that pre-tension and elastic modulus show positive influences while tex, bending, rigidity and compressibility of threads show negative effects on tension peaks during tightening and needle piercing. Sewing speed shows a positive impact only on the tension peak due to needle piercing. Pre-tension showed a prominent influence on tension peaks on all threads while the number of fabric layers failed to show any effect.

A simple system for the online detection of skip/loop stitches in single needle lockstitch sewing machines

Wesley D. S., Poojitha V.

Autex Research Journal

2010

Vol. 10, no. 3

69--72

In single needle lockstitch sewing machines, the needle thread consumption of 10 normal stitches for a fabric with a particular number of layers at a particular stitches per unit length is manually measured kept as a reference value. If the value of needle thread consumed per stitch is very small, the length of thread consumed per 10 stitches is used as a comparing value. The actual thread consumed for every 10 stitches is measured online by a rotary optical encoder sensor by converting the angular movement into the linear movement of the thread and continually compared with the reference value. If the online measured length is more or less a buzzer sounds to indicate the variation. The counting of every stitch formed is undertaken by a proximity sensor by sensing the protrusion in the hand wheel of the machine, which rotates once for every rotation.