What is the working principle of sewing machine? How did you sew it on?

Sewing machine is a machine that uses one or more sewing threads to form one or more stitches on sewing materials, so that one or more layers of sewing materials are interwoven or sewn together. The sewing machine can sew cotton, linen, silk, wool, man-made fiber and other fabrics and leather, plastic, paper and other products. The sewing stitch is neat, beautiful, flat and firm, with fast sewing speed and simple use.

1790, St. Thomas, England invented a single-thread chain stitch manual sewing machine for sewing boots and shoes. This sewing machine is made of wood, and some parts are made of metal. This is the first sewing machine in the world.

184 1 year, Timoni designed and manufactured a practical double-thread chain stitch sewing machine. 1846, Howe, USA, obtained the patent of curve sewing machine, with sewing speed of 300 stitches/min and efficiency exceeding 5 manual sewing workers; 185 1 year, American mechanical worker Shengjia independently designed and manufactured a sewing machine with a sewing speed of 600 stitches per minute, and obtained an American patent in 1853. Since then, sewing machines have been widely used in production, and gradually increased the functions of nailing, buttonhole locking, reinforcement, embroidery and so on.

1975, the United States invented a multifunctional sewing machine controlled by a microcomputer. Professional industrial sewing machines have developed more widely and the sewing speed is getting higher and higher. For example, the sewing machine has reached 65,438+00,000 stitches per minute. 1979 The total output of sewing machines in the world reached15,885,000, of which the output of China was 5,870,000, ranking first in the world.

There are many ways to classify sewing machines, and the common one is to distinguish them by stitch and use. The stitch of sewing machine can be divided into lock stitch and chain stitch. Lock stitch is the most common stitch, which consists of two stitches, intertwined like a rope, and its interweaving point is in the middle of sewing materials. From the cross section of the stitch, two stitches are like two locks, so it is called a lock stitch. This stitch is used to sew materials such as cotton, wool fabric or leather with small shrinkage, and the front and back shapes are the same, such as the dotted line. The stitch distribution is dense, and the sewing fastness is generally higher than that of manual sewing.

Chain stitch is formed by self-connection or mutual connection of stitches, and commonly used are single-line chain stitch, double-line chain stitch and three-line wrapped stitch. This stitch is characterized by elasticity, which can expand and contract with the sewing material without breaking the sewing thread. It is suitable for garments made of linear elastic fabrics or products and garment grey cloth that is easy to loosen.

General sewing machine consists of four parts: head, frame, transmission and accessories.

The nose is the main part of sewing machine. It consists of four mechanisms: piercing, hooking, picking and feeding, and auxiliary mechanisms such as winding, pressing and tooth dropping. All mechanisms work in a reasonable and coordinated way, working in cycles, and sewing materials.

The frame is divided into two forms: bed board and chassis. The bed plate of the bed plate frame plays the role of supporting the machine head and is used as a workbench during sewing operation. There are many styles of bed boards, including one or more bucket folding, cabinet type, desktop type and so on. The chassis of the chassis frame plays the role of supporting and storing the machine head, which makes the sewing machine easy to carry and keep.

The transmission part of sewing machine consists of frame, hand crank or motor. The frame is the pillar of the machine, supporting the base and pedals. When in use, the operator steps on the pedal to drive the pulley to rotate through the crank, and then drives the machine head to rotate through the belt. Most hand cranks or motors are directly mounted on the nose.

Accessories of sewing machine include needles, spools, knives, oil pots, etc.