Application Of Omron Cj1 Series Plc In Glass Tempering Furnace

I. Introduction
　　Luoyang North Glass Technology Co., Ltd. (abbreviated as North Glass Technology Co., Ltd.) Luoyang North Glass Technology Co., Ltd. (abbreviated as North Glass Technology Co., Ltd.) was founded in 1995. It is a high-tech enterprise integrating the design, manufacture, sale of glass deep processing equipment and the production and sale of high-end deep processing glass products.Omron The main products are FRP equipment and its accessories, low radiation coated glass equipment and its accessories, safety glass and energy-saving glass.Omron The company concentrates on the research and development of glass deep processing technology and equipment, has complete industrial chain and continuous independent innovation ability, ranks as the leading glass deep processing equipment industry CJ1 series tempering furnace annual output of more than 300 sets, the glass deep processing equipment produced by the company is exported to many countries and regions in the world, including the European and American market CJ1 series.

Figure 1 Office Building Figure 2 Steelmaking Equipment
II. Systematic Introduction
1. Brief process introduction
Horizontal roller type glass tempering furnace (fig. 2) is not only the developed product of Beibao, but also one of its main products. The simple block diagram of CJ1 series is as follows:

After the glass is heated to the specified temperature in the heating section, the process of rapid cooling with cooling medium is adopted. The common flat glass of the glass tempering furnace is conveyed to the heating furnace through the upper roll table, which is driven by the heating roll table to oscillate back and forth in the heating furnace. The glass is evenly heated to the process temperature and then sent to the grille roll channel for strong air quenching, and then cooled at a fixed time. It is sent to the discharging roller, that is, the glass tempering furnace which completes a cycle of production process.
2. System Hardware Architecture
　　The control system of tempering furnace is mainly divided into two parts: temperature control and glass conveying control. At present, the way we adopt for temperature control is mainly board card and module. In this paper, the glass conveying control of tempering furnace is mainly introduced, and the conveying control system is mainly composed of PLC and corresponding actuator.
　　From the above-mentioned simple block diagram, the glass conveying control is not complicated, but the system requires very high security and stability. In addition, the tempering furnace belongs to non-standard equipment with a wide variety of types. Because of our large output, it also requires a high degree of standardization of the procedures. OMRON has always been our partner. The first one we used was the C200HG PLC of OMRON. In order to further improve the standardization of the program, it was upgraded to OMRON CJ1 series PLC. The hardware configuration of a certain type of steelmaking furnace is as follows:
1) PLC configuration: power supply: CJ1W-PA205R 1, CPU; CJ1G-CPU43H 3.0 version 1, high-speed counting: CJ1W-CT021 1, analog unit: CJ1W-DA08C, output: CJ1W-OC2112, input: CJ1W-ID2112.
2) Encoder 2, sensor several, frequency converter 6.
III. Functions of Control Systems
1. Process Action Process
　　Glass tempering furnace is mainly composed of four parts: upper segment, heating section, forming section (including air-cooled section) and extracting segment. Frequency converter is equipped in each section by PLC automatic control to make infinitely variable speed, so that the speed of each section can be completely synchronized. The system uses PLC as the central controller to complete the tasks of time sequence logic control of the system movement and state alarm display. A rotary encoder is installed on the heating roller and the air-cooled roller to detect the moving position of glass in the heating roller and the air-cooled roller, so as to ensure the accurate positioning of glass in the whole production line, the operation control of the system, real-time data acquisition and monitoring of the operation process, the display and setting of various parameters are realized by industrial computer. Now. See Figures 3 and 4.

Figure 3 PLC control cabinet Figure 4 Inverter control cabinet
　　The glass is transported to the upper eyesight through the upper stage for waiting. When the feeding condition is satisfied, the upper plate and the furnace body drive synchronously to transport the glass to the furnace. The glass is heated evenly in the heating section, and the heating timer is started for heating time. Because the length of the furnace is limited and the glass can not stop, the glass swings back and forth in the furnace until the heating time is reached. When the heating time is up, open the back door and prepare for discharging. When the furnace is discharged, the heating section and the forming section are driven synchronously, and the glass is conveyed to the forming section. In the process of glass conveying into the forming section, according to the different forming process, the cooling system is started and the cooling time is counted. The glass in the forming section, like in the furnace body, also swings back and forth until the cooling is finished. After cooling, the glass is transported to the segment by the forming section and the extracting section together, and then removed by the workers. That is to complete a production cycle.
2. Process characteristics
　　From the process point of view, the conveying control is very simple, but there are still some requirements: 1) When the glass is conveyed from the previous section to the next section, the speed synchronization between the two sections is very high, otherwise the contact surface of the glass will be scratched, so the conveying speed control should be precise; 2) When the glass enters the heating section, the heating section. The movement must be reliable and there must be no errors, otherwise the glass will be softened and stick to the roller, which will damage the roller. The roller in heating section uses ceramic roller, which is expensive, so the operation of heating section must be stable and reliable. 3) The forming section has both flat and curved surfaces. When non-flat glass is used, it is required. The positioning accuracy should be high and the repetition accuracy should be high, otherwise the products produced can not meet the requirements.
3. Programming
　　CJ1 PLC has task programming and function block programming. According to the structure of the equipment, the equipment can be divided into several tasks, such as chip, heating, shaping, air cooling and chip taking. These tasks can be accomplished by one person or by more than one person. Finally, each task can be invoked according to the conditions. This is to divide the tasks according to the structure of the equipment, and to program the function blocks according to each function: conveying function, reciprocating function, timing function, counting function, transmission alarm, etc. A function block can be written with the same or similar functions, and only the code can be invoked when the same or similar functions need to be performed in different tasks. A good function block is enough to avoid repetitive programming. See Figure 5.

Fig. 5 Engineering and Programming Areas of the Program
　　IO addresses can be artificially specified, not only for hardware slots, but also for reserved empty slots to set up a virtual address. When modules are added later, additional modules will be added. In this way, when considering the program framework, it is not necessary to consider the changes of hardware. When programming, IO address is determined in advance. When the hardware is determined, only IO table can be changed. No module is set to virtual address, and no program need to be changed. For non-standard equipment, it not only saves the development time of the program, but also does not modify the program according to the change of hardware, so as to realize the standardization of the program; moreover, because there is no need to add any occupying module in the vacant position, and no need to place spare module, thus greatly reducing the cost of hardware. See Figure 6.

IV. Project Operation
　　The project has been upgraded from C200HG to CJ1 system for more than six years. There are more than 1,000 equipments using CJ1 system, and more than 1,000 equipments are exported to foreign countries. The operation is very stable, and the use and maintenance are very convenient, which has won unanimous praise from customers at home and abroad.
5. Experience in application
1. CJ1 is compact, space-saving, high-speed and flexible instructions;
2. Task-based programming, virtual address programming and function block programming not only simplify the programming process, but also avoid repetitive programming of the same function, save development time, and improve the standardization of the program.
3. The use of CJ1 system greatly improves the accuracy of equipment positioning, operation stability and reliability, thereby improving production efficiency and application.