Since my country's entry into the WTO, the textile industry has ushered in another upsurge of development. From the perspective of the fabric market, it is the domestic market and the international market. The requirements are getting higher and higher, and the variety of patterns is changing faster and faster. This makes the loom more adaptable to the fabric and higher production efficiency. At present, most of the rapier looms in our country are in the middle and low level, and the operating speed is 300
Around 40or/min. The performance of a loom is an important indicator of the mechanical part and electrical control level. The electrical system of the rapier loom is mainly composed of the control part and the detection part. The current situation of the domestic loom mainly reflects the following aspects.
1 control part
The control part has two forms: single-chip control and PLC control. These two forms have their own characteristics, the single-chip control cost is low, and the production is easy; the disadvantage is that the stability, reliability and anti-interference ability are poor, the quality of electronic components cannot be guaranteed, and the maintenance costs of manufacturers and users are high. The biggest feature of PLC control system is high reliability and stability, and strong anti-interference ability. Many of its functions are realized by software technology, which can reduce the use of peripheral hardware and reduce the probability of failure. Generally, PLCs have a normal operating life of 50,000 to 100,000 hours. At present, there is no suitable PLC product in China
The market is basically monopolized by foreign manufacturers, and the cost is more than that of single-chip microcomputers.
To be higher. But considering its reliability and stability, PLC is selected
More and more manufacturers.
2 Detection part control system The detection element provides signals to control the loom, and the role of the detection element is very important. Proximity switches are often used as detection elements in looms. The reliability of proximity switches is an important issue in long-term high-speed operation. An occasional error may result in defective fabrics. The solution to this problem is to switch to a rotary photoelectric encoder, which can quantify the mechanical position of the machine into an angle, and the PLC angle controls the loom. The rotary photoelectric encoder is a photoelectric device with strong anti-interference ability, can work in different environments, and has a life span of more than 10 billion times.
3 Function PLC is superior to single-chip control in terms of reliability and stability, and achievable functions are also stronger than single-chip, these functions are divided into basic functions
Accessibility and management functions.
3.1 Basic functions The basic functions include electronic color selection (8 colors, 3000 latitudes or more); stop for broken warp, weft, and heavy weft; automatic weft finding (6 kinds of weft finding programs); fault stop light alarm; position setting (normal Setting of parking spaces, faulty parking spaces, and weft detection area).
(1) Chinese display interface, intelligent man-machine dialogue, able to display various parameters of the loom under different conditions. During normal operation, the current loom operating angle, operating speed, fabric serial number, and fabric color number are displayed. When parking, the reason for parking and the current angle are displayed.
(2) Fault self-diagnosis function, divided into soft and hard faults. Soft faults: broken warp, broken weft, heavy weft; hard faults: brake failure (causing angle inaccuracy) dobby machine contact failure (causing weft search can not be completed) clutch failure (causing the loom can not start). In addition to the Chinese display on the interface, the above-mentioned faults are also accompanied by a light report.
(3) System test function (non-operating state), which can detect jog, start, normal stop, forward and reverse weft seeking, broken warp, broken weft, and heavy weft, which is convenient for loom inspection, maintenance, and fault diagnosis.
(4) Safety protection function. If the loom does not move within three minutes, the color selector will automatically power off. Press jog or start, the color selector will automatically restore power. The hardware design should have the effect of absorbing the arc (spark) generated by braking and eliminate the hidden danger of fire. Power-down data protection in various operating states, and the actions before power-down can be continued after the power is restored.
(5) Diversified color selection program settings. The color selection program of the PLC electronic control system can be set in a single unit using the man-machine interface on the control cabinet. Complicated program or program setting of multiple looms can be done with a special laptop computer (such as SEMENSMOBIC). Put the required program MOBIC in advance
It can be edited and stored on the computer and can be called directly when needed. Network PC is also available
3.3 Management function (1) The system has built-in records of the respective output and production efficiency of the four shifts. The number of warp, weft, and repetitive wefts can be inquired at any time to call the set drop length (such as 1km). When the output reaches the set value, it will stop and change the length. Axis and reset to continue production. It can be used for adding and subtracting weft in the running state to facilitate color matching.
3.4 Networked management and control Using PP network, all looms can be networked, and the entire production situation can be monitored with a PC and the production data can be read. At the same time, it can also forward instructions downwards to modify the production process parameters. Connected to the INTERNET network, remote diagnosis of the loom can be carried out.
4Comprehensive comparison From the analysis of the production status of domestic textile machinery factories, such as Jiangsu Gaochun, Zhejiang Titan, Shanxi Jingwei, Wuxi Longli, etc., except that Zhejiang Titan has absorbed the original SM93 circuit board function and made a few changes and integrated it into two large circuit boards, All other manufacturers use PLC as the core and use rotary photoelectric encoder as the detection element as the main electronic control device, which not only simplifies the hardware design, reduces the point of failure, but also improves the reliability and stability of the system. To the user’s approval, this shows The system design is fully mature and represents the development direction of rapier looms.