Types and structures of circular knitting machines

The types and structures of circular knitting machines: Circular knitting machines are the core equipment for the large-scale production of knitted fabrics. Their classification dimensions are clear, and their structural design is centered around the function of loop weaving. Different models are suitable for different fabric production needs. I. Core Types of Circular Knitting Machines The classification of circular knitting machines is mainly based on the number of needle beds, fabric structure, and specialized functions. The mainstream models are as follows: 1. Classification by the number of needle beds: Single-sided circular knitting machines: With only one needle bed, they have a relatively simple structure, occupy less space, and are easy to operate. It is mainly used for weaving single-sided fabrics such as plain weave fabric, beaded mesh fabric and sweat fabric, and is suitable for the production of light and thin fabrics such as underwear and T-shirts. Double-sided circular knitting machine: Equipped with two needle beds at the top and bottom, the needle beds can be combined in different ways to form loops, capable of weaving double-sided fabrics such as cotton and wool cloth, ribbed cloth, and air layer. The fabric has a tight structure, better elasticity and warmth retention, and is widely used in the weaving of thermal underwear, sweatshirts and outerwear fabrics. 2. Classified by dedicated functions, jacquard circular knitting machines: Equipped with electronic needle selectors or mechanical jacquard devices, they can form complex patterns on the fabric surface. They are divided into single-sided jacquard machines and double-sided jacquard machines, and are suitable for the production of high-end clothing and home textile decorative fabrics. Ribbed circular knitting machine: The needle bed adopts a ribbed configuration and is specifically designed to weave ribbed fabrics of different proportions such as 1×1, 2×2, and 3×2. The fabrics have excellent elasticity and are often used as clothing accessories for collars, cuffs, HMS, etc. It can also produce fully ribbed fabrics. Loop large circular knitting machine: Through a special settling plate structure, loops are formed on the fabric surface, which can be used to weave towel fabrics, sweatshirt fabrics, etc. The length and density of the loops can be adjusted through the process to meet different softness requirements. Spandex elastic circular knitting machine: Equipped with an elastic yarn feeding device, it can precisely control the tension of spandex yarn to weave elastic sweat fabric, elastic ribbed fabric, etc., meeting the elasticity requirements of tight-fitting clothes, sportswear, etc. Ii. Basic Structure of the Circular Knitting Machine The structure of the circular knitting machine is designed around the four core processes of “loop forming - yarn feeding - drawing - winding”, mainly composed of the following components, which work in coordination to ensure continuous and stable weaving: 1. Main frame: It is welded from cast iron or steel and serves as the supporting foundation of the entire machine, including the base, column, upper frame and other parts. It needs to have sufficient rigidity to prevent vibration during high-speed operation. 2. Weaving mechanism: The core loop-forming component, which determines the fabric’s organizational structure, is a key part of the entire machine. Syringe and needle bed: A single-sided machine only has a round syringe, while a double-sided machine includes an upper needle bed and a lower syringe. The needle cylinder wall is covered with needle slots, into which knitting needles are inserted. The lifting and lowering movement of the knitting needles completes the circular action. Knitting needles and settling plates: The knitting needles are responsible for hooking the yarn to form loops, while the settling plates assist the knitting needles in pulling, bending the yarn and unwinding the loops, ensuring a smooth loop formation process. Triangular device: Fixed on the outside of the syringe or above the needle bed, it controls the up and down trajectory of the knitting needle through a triangular track. Different triangular arrangements can produce fabrics of different structures such as plain weave, rib weave, and jacquard weave. 3. Yarn feeding mechanism: It is responsible for uniformly and stably conveying the yarn to the weaving mechanism. The core components include the yarn feeder, tensioner, and yarn storage device. The yarn feeding tension and speed can be precisely adjusted according to the type of yarn (such as cotton yarn, spandex yarn) and fabric requirements to avoid fabric surface defects caused by uneven tension. 4. Traction and winding mechanism: It pulls the woven fabric out of the weaving area and winds it into a fabric roll. The rotational speed of the traction roller needs to be precisely matched with the weaving speed to prevent the fabric from stretching and deforming. The winding device can adjust the tension of the wound fabric to ensure that the fabric is tightly rolled and neatly arranged. 5. Transmission mechanism: It provides power for the entire machine and includes components such as motors, pulleys, and gearboxes. It can achieve stepless speed regulation to meet the weaving speed requirements of different fabrics and patterns. 6. Electrical control system: Composed of PLC, touch screen, sensors, etc., it is used to control the operation of the entire machine, speed regulation, needle selection (specifically for jacquard machines), and other functions. Some high-end models support remote monitoring and fault diagnosis.