introduction

In the field of textile engineering, weaving and weaving are two completely different processes. Spinning is an early process of weaving. Twisting belongs to the later process of spinning. For spun yarns, twisting makes the fibers more tightly entangled, so that the yarn has certain physical and mechanical properties; for filaments, the purpose of twisting is to improve the processability of the weaving, and improve the anti-pilling and anti-pilling of textiles. Snaking and strong twist make the fabric unique. Twisting is the relative rotation of the two cross-sections of the yarn. At this time, the fibers originally parallel to the yarn axis in the yarn are inclined into a spiral. The amount of twisting of the yarn and the matching of the twist direction and twist of the yarn in the fabric have a greater impact on the appearance and performance of the product. The indexes of twisting properties are: the twisting degree, the twisting coefficient, and the twisting direction that indicates the twisting direction. The twist direction of the yarn has a great influence on the appearance and feel of the fabric. Using the twist direction of the warp and weft yarns to match the fabric weave can weave fabrics of different styles such as appearance and feel.

As a kind of twisting equipment, the two-for-one twister realizes one-turn two-twist, the efficiency is doubled compared with the traditional twisting machine, the package capacity is increased, and the twisting quality is greatly improved. The two-for-one twister mainly has the following characteristics: high-quality spindles have long-lasting stability under high-speed operation; two-level transmission mechanism makes the force more reasonable and the twisting range is wider; oil bath type gear box, special yarn guide curve, make The winding shape is good; the winding tension can be adjusted arbitrarily on the super feed roller, so it is also suitable for loose and soft winding for dyeing.

Principle of two-for-one twister system

1. Two-for-one twisting machine is mainly composed of power part, two-for-one twisting unit and transmission part.

(1) The power part mainly includes electric motor, electrical control box, indicator and operation panel.

(2) The structure of the two-for-one twisting unit mainly includes the spindle brake device, the spindle part of the two-for-one twister, the yarn winding system, and the special device of the two-for-one twisting unit.

(3) The transmission part is mainly the motor drives the spindle through the belt drum, belt, and spindle belt, which is transmitted from the spindle belt to the winding roller, overfeeding roller, etc. through the toothed belt, deceleration device, etc. At the same time, the transmission of the traverse cam is changed into the reciprocating motion of the slider, which drives the traverse yarn guide to reciprocate.

2. The overall structure of the two-for-one twister is as follows:



3. Working principle of two-for-one twister

The spindle rotates once, and the yarn forms two twists, hence the name double twist. The twisting process is completed by the spindle. The first twist is formed at the tension pin and the outlet of the spindle; the second twist is formed between the outlet of the spindle and the yarn guide. Due to the traction of the output mechanism, the yarn exits from the feeding bobbin in the spindle tank and enters the center hole of the hollow spindle. In the hollow spindle, the yarn is controlled by a tensioner, that is to say, as shown in the figure above, when the dragon belt drives the spindle to rotate, the friction drum also drives the twisting drum to rotate, so that the yarn enters the tension tube from the yarn supplying drum. Passing through the tension bead, it is compressed by the elastic action of the tension bead to form a holding point. The yarn retreats from the center hole of the hollow spindle and enters the spindle vertically, and then the yarn is deflected from the outlet of the spindle through the yarn storage area to stop. The yarn guide hook and the air ring are formed. The height of the air ring is determined by the position of the yarn guide hook. After the yarn passes through the yarn guide hook, it passes through the small yarn guide roller to reach the super micro roller, and finally the yarn passes through the yarn guide for cross winding Wound on the bobbin.

4. Application principle of frequency converter:

The two-for-one twister belongs to the equipment for the preparation process before weaving. As a kind of twisting equipment, the traditional two-for-one twister uses only one electric motor as the power, which is distributed to the spindles, winding shafts and traverses through the belt drive mechanism and gear mechanism. Pendulum. The two-for-one twister is twisting yarns of different counts and strands, and the spindle speed needs to be changed. The traditional two-for-one twister completes this process by replacing the belt pulley, which is not only inefficient, but also needs to be completed by professional maintenance workers. With the continuous development of modern variable frequency drive technology, stepless speed regulation of three-phase asynchronous motors becomes possible. More importantly, driven by the frequency converter, as the power factor of the motor increases, its operating current decreases, thereby reducing equipment power consumption and operating costs.


5. Technical characteristics of Robin Kang inverter

Robin Kang frequency converter is a high-performance vector frequency converter. Through the decoupling control of the motor flux current and torque current, it realizes the rapid response and accurate control of the torque, and can carry out high-precision and wide-range speed regulation operation and Torque control. There are a variety of frequency setting methods and starting methods. The speed stabilization accuracy can reach 0.5% or less of the rated synchronous speed. The speed control stability can reach 0.3% or less of the rated synchronous speed. The torque response is less than 40ms. The multi-point V/F curve makes the torque increase more stable and efficient.

6. Advantages of the application scheme

The use of frequency converter drive technology focuses on the convenience of driving ordinary three-phase asynchronous motors to achieve stepless speed change, while optimizing the power factor of the motor. As the speed changes, the operating current changes accordingly to achieve the purpose of energy saving; its main advantages after the frequency conversion transformation Mainly reflected in the following aspects:

a. It has a significant power-saving effect. Driven by the frequency converter, as the power factor of the motor increases, its operating current decreases, thereby reducing equipment power consumption and saving operating costs.

b. It is convenient and quick to modify the process parameters. When twisting different yarns, there is no need to replace the belt pulley, and directly adjust the actual panel speed of the frequency converter to achieve stepless speed regulation to meet the production process requirements and improve the yarn quality. The operation is convenient and quick, and ordinary workers can complete it.

c. Smooth start, the application of AC frequency conversion technology can solve the smooth start. The acceleration time of the equipment can be set artificially, which effectively eliminates the impact force during mechanical start and prolongs the service life of the equipment.

d. It has a protection function for the motor and reduces the maintenance cost of the motor. Using frequency conversion control, the control of electrical circuits is more simple and clear. At the same time, the variable frequency drive itself is designed with rich motor protection functions, which can effectively prevent the motor from burning under the conditions of motor overcurrent, overload, and stall.

e. The starting current is small, reducing the capacity of the power supply equipment.


Precautions and daily maintenance of the inverter in use

1. Floss has always been a big problem in the textile industry. It is easy to block the vents, resulting in poor heat dissipation and overheating. Therefore, it is necessary to clean the floss regularly to avoid affecting the heat dissipation of the inverter

2. When not in use for a long time, ensure to be powered on once a month

3. Ensure that the electrical cabinet and vents are unblocked


Concluding remarks

With the development of electrical automation, electrical control is becoming more and more intelligent, and people’s living standards are improving, and higher and higher requirements are placed on the accuracy of textile processing. Servo, PLC, and man-machine interface are gradually added to the two-for-one twister system. The frequency converter communicates and controls with them, which greatly improves the operating speed of the system, not only improves the accuracy, but also increases the production speed.