Design and Fabrication of an Automatic Tension Monitoring and Regulation System for Needle Thread

摘要

A matched needle and bobbin thread tensions is a major requirement of a seam and also to the quality of garment. This paper describes an attempt on the development of an automated needle thread tension regulating system for single needle lock stitch sewing machine. Historically, several experiments have been carried out to measure the thread tensions of both needle thread and bobbin thread of a lock stitch machine. However, no evident in favour of the development of a device to adjust the needle thread tension automatically. Despite a cyclic variation of the needle thread tension, a needle thread regulation system is developed to maintain an average needle tension during the cycle at a predetermined level. The developed system can be installed on an existing single needle lock stitch machine and capable of maintaining the required correct thread tension profile for sewing. The needle thread tension regulation system is a closed loop system and with a load cell as a sensing device and a geared DC motor adjusts the compression of the spring of the thread tensioner. A visual display of thread tension is indicated on a 16X4 LCD display and the required needle thread tension is set by 4x4 keypad. An Arduino board controls the electronic equipment in the system.