• Fashion & Textile Research Journal
• /
• v.3 no.1
• /
• pp.25-30
• /
• 2001

In order to investigate the influence of thread tension on the structure of lockstitch seam, stitch tightness and seam balance ratio are measured at various tensions of needle thread and bobbin thread. The structure of lockstitch was shown in terms of skeleton stitch models to obtain quantitative analysis of stitch tightness. The balanced seam formed to the rectangu1ar stitch model under low bobbin thread tension, but the fabric tightness produced by interlaced needle and bobbin thread under high bobbin thread tension. In this paper, new equation to obtain seam balance ratio was proposed for a lockstitch seam. By using the new equation, the seam balance ratio was not affected by the stitch density and fabric thickness. In order to form the balanced seam, the ratio on tension of needle thread and bobbin thread was about 6:1~7:1 in this experiment.

• The Research Journal of the Costume Culture
• /
• v.21 no.6
• /
• pp.967-973
• /
• 2013

During high speed sewing, the needle thread is exposed to dynamic loading, short strike loading, inertia forces, friction, rubbing, force of check spring, bending, pressure, friction, impact, shock and thermal influence. The dynamic thread loading/tension alters throughout the stitch formation cycle and along its passage through the machine. The greatest tensile force occurs at the moment of stitch stretching, when the take up lever pulls for required thread length through the tension regulator. These stresses act on the thread repeatedly and the thread passes 50-80 times through the fabric, the needle eye and the bobbin case mechanism, before getting incorporated into the seam, which result in upto 40% loss in tensile strength of the sewing thread. This damage in the sewing thread adversely affects its processing and functional performance. In this paper, the contribution of dynamic loading, passage through needle and fabric, and bobbin thread interaction in the loss in tensile properties has been studied. It is observed that the loss in tensile properties occurs mainly due to the bobbin thread interaction. Dynamic loading due to the action of take up lever also causes substantial loss in tenacity and breaking elongation of cotton threads.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.38 no.10
• /
• pp.1085-1091
• /
• 2014

We developed a single-channel thread sensor for a rotary bobbin by optical sensing and analyzed the signal characteristics. A specially designed mount made of ABS (acrylonitrile-butadiene-styrene) resin that encapsulated an optical sensor was fabricated by using a 3D printer and was attached to the rotary bobbin system. Stable control on a weaving machine was achieved by observing the difference in the output signals of an optical sensor system, which vary significantly according to the states of the thread in the weaving operation. The optical sensor effectively detects an unintentional thread cut and run-out during weaving fast enough to enable prompt stopping of the weaving machine, thereby minimizing the loss of expensive fabrics.

• Journal of the Korean Society for Precision Engineering
• /
• v.27 no.4
• /
• pp.72-78
• /
• 2010

Textile machinery affects various industry, such as sport leisure industry, metal and chemistry material, electric electron, mechanical energy, packing and printing industry. In case of design of textile machine, the very important fact is absorbing the minute vibration induced by spinning thread and insert which is the part of spindle plays a role of reduction of impact caused by oscillation of thread bobbin. Therefore, Optimal design was executed by design of experiments and kriging optimal design methods to prevent fracture of spindle insert under the fatigue condition and deduced the best value of design parameter to improve the stability of the products. The highest sensitivity is showed at the design parameter A and D. As the spiral number of insert is increase, tension force applied its edge is distributed at whole model and the stress concentration is reduced.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.13 no.1
• /
• pp.53-60
• /
• 2018

The ICT concept has been introduced to realize a highly productive smart factory and respond to the demand for small quantity and mass production between textile processes. ICT convergence monitoring system that can produce high productivity textile products by improving product development period, cost, quality and delivery time through ICT based production and optimization of manufacturing process is needed. In this paper, we propose and implement a system design that senses the amount of remaining sewing material using a non-contact sensor that can be mounted on a sewing machine and displays it on a display using IOT-based LATTE-PANDA board.

• (The)Study of the Eastern Classic
• /
• no.35
• /
• pp.135-159
• /
• 2009

Since the military servants' rebellion, the society of the Goryeo(高麗) dynasty had been getting into crisis worse and worse until late in it. Late in the 14th century, the society was constantly meeting tension and chaos including decline of the Yuan(元) dynasty, sudden rise of the Ming(明) dynasty and etc. This study is aimed to investigate the idea of justice and theory of governing advocated by Yaeun Jeon Nok Saeng, who lived in such tensed and chaotic era. Under the circumstance that threatened the national power of the Goryeo dynasty in the era where the Yuan dynasty changed to Ming dynasty, his idea of justice was expressed as "Theory for Friendship with Ming and Against Yuan", which was proposed in the aspect of considering the safety and maintenance of the nation and getting back the original national power of a country Goryeo. He thought that you should not make your people bothered by or troubled in their works but you should make them concentrate on their jobs for living to govern them eased. He emphasized that you should focus on stability of people's welfare in gentle ways not bothering your people even a little bit because he thought that the situation of that era looked like a thread bobbin so that it could get naturally and easily twisted if you went in hurry.