A sewing machine is a machine that uses one or more sewing threads to form one or more stitches on the sewing material, so that one or more layers of sewing material are interwoven or stitched together. The sewing machine can sew cotton, linen, silk, wool, man-made fibers and other fabrics and leather, plastic, paper and other products. The stitches sewn are neat and beautiful, flat and firm, and the sewing speed is fast and easy to use.
In 1790, St Thomas of the United Kingdom invented a hand-operated sewing machine with single-thread chain stitches for sewing boots and shoes. This sewing machine uses wood as the body and some parts are made of metal materials. It is the first sewing machine in the world. .
In 1841, Timonière of France designed and manufactured a practical double-thread chain stitch sewing machine; in 1846, Hao of the United States obtained a patent for a curve lock stitch sewing machine with a sewing speed of 300 stitches per minute and an efficiency of more than five Hand-operated sewing master; in 1851, the American mechanical worker Shengjia independently designed and manufactured the Shengjia sewing machine with a sewing speed of 600 stitches per minute, and obtained a US patent in 1853. Since then, sewing machines have been used in large quantities in production, and the functions of button nailing, button hole locking, reinforcement, and embroidery have been gradually added.
In 1975, the United States invented a multifunctional household sewing machine controlled by a microcomputer. The development of professional industrial sewing machines is more extensive, and the sewing speed is getting higher and higher. For example, the overlock sewing machine has reached 10,000 stitches/min. In 1979, the total output of sewing machines in the world reached 1,5885,000, of which China’s output was 5.87 million, making it the country with the highest output of sewing machines in the world.
There are many classification methods for sewing machines, and the more common one is to distinguish them by stitches and uses. The stitches of the sewing machine can be classified into two types: lock stitch and chain stitch. The lock stitch is the most common. It consists of two sutures, which are interwoven with each other like a twisted rope. The interlacing point is in the middle of the sewing material. Viewed from the cross section of the stitches, the two stitches are like two locks locked to each other, so they are called lock stitches. This stitch is used for sewing materials such as cotton, wool fabric or leather with low shrinkage. The front and back sides have the same shape, like a dotted line. The stitches are densely distributed, and the sewing fastness generally exceeds that of manual sewing.
Chain stitches are formed by self-connection or interconnection of suture loops. Commonly used are single-thread chain, double-thread chain and three-thread overlock stitches. This kind of stitch is characterized by its elasticity, which can stretch with the sewing material without breaking the stitch. It is suitable for clothes made of thread elastic fabrics or products and garment blanks that are easy to be sewn.
General sewing machines are composed of four parts: head, base, transmission and accessories.
The head is the main part of the sewing machine. It is composed of four mechanisms of material stabbing, thread hooking, thread take-up and feeding and auxiliary mechanisms such as thread winding, material pressing and tooth drop. The movement of each mechanism is reasonably coordinated, working in cycles, and sewing the sewing materials together.
The base is divided into two forms: table plate and case. The platen of the platen type machine base plays a role of supporting the machine head and is used as a worktable during sewing operations. There are many styles of tabletops, such as folding Tibetan style, cabinet style, writing desk style, etc. The case of the case type machine base plays a role of supporting and storing the machine head, making the sewing machine easy to carry and store.
The driving part of the sewing machine is composed of parts such as frame, hand crank or motor. The frame is the pillar of the machine, supporting the platform and pedals. When in use, the operator steps on the foot pedal, the crank drives the rotation of the pulley, and the belt drives the head to rotate. Most hand cranks or motors are directly mounted on the machine head.
The accessories of the sewing machine include needles, bobbins, knives, oil cans, etc.
Classification of sewing machines:
By use: household, industrial, service industry
According to the driving form: hand crank, pedal, electric
Divided by stitches: single thread chain stitch, multi-thread chain stitch, lock stitch, imitation hand stitch stitch, hemming chain stitch, covered chain stitch
Take out the thread shuttle (a lot of messy threads will be stuck inside, take out all of them), pull the thread with a hand, if it is tight, use a screwdriver to loosen it, if it is normal, add one or two sewing machine oil and step on it a few times Sewing machine.
If it is not normal anymore, turn on the sewing machine, use gasoline to add gasoline to every moving part of the sewing machine (including the foot part), and then keep stepping on the sewing machine (it may be useless for a long time. The oil of the sewing machine is dry, and the thread delivery mechanism of the sewing machine is stuck) until the sewing machine is lightly stepped on, wipe off the dirty oil with toilet paper and try again.
After doing these attempts, it is still not normal, only ask the master to repair (maybe the parts are worn and need to be replaced).
