Design of CNC system of induction hardening machin

2022-10-23
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CNC system design of induction hardening machine tool based on IPC

<1. Metal material testing machine: 1. Generally, it is a large-scale tensile machine, zigzag testing machine, folding resistance testing machine with more than 2T pneumatic force; p> Background introduction in recent years, with the development of computer network, the application of enterprise resource planning (ERP) has become increasingly popular, and the research and application of manufacturing execution system (MES) have also been highly valued by the industry. Induction heat treatment machine tool is a kind of clean heat treatment equipment, which meets the 3S standard of modern industrial production (sure reliable, safe, saving). It can also be installed on the production line for metal heat treatment. It has been widely used in the mechanical heat treatment industry at home and abroad. When manufacturing multi-functional rotary quenching machine tool, we developed a numerical control system supporting Fieldbus to make the machine tool support industrial Ethernet, Then it can exchange information with workshop level network and set remote quenching parameters

introduction to multifunctional rotary quenching machine tool

induction heating uses electromagnetic induction to heat conductor materials. Its main advantages are: high efficiency, low cost, energy saving, easy to realize automatic control. Induction heating equipment for metal heat treatment mainly includes: heating power supply, induction heat treatment equipment, enterprise bed, inductor and quenching transformer

the multi-function rotary quenching machine tool is actually an automatic processing line with perfect protection function. It adopts the rotary structure, so that the loading and unloading can be completed at the same position, and the operation is convenient; The machine tool can process three different surfaces on the same part at the same time, so that a workpiece can be quenched on a quenching machine tool at one time, and three identical or different parts can be quenched at the same time. The parameters of each processing station are set with a certain degree of flexible redundancy, which can realize various quenching methods, such as time, continuous, continuous simultaneous and multi-stage quenching. It is mainly used in the automobile and motorcycle manufacturing industry, To meet the quenching treatment of many varieties and small parts

1. Integrated design

in order to reduce the floor area and installation cycle, the integrated design is adopted, that is, the machine tool is integrated with the quenching liquid circulation system, the coolant circulation system, the heating power supply and the quenching transformer

2. Production line

CNC system design

requirements for multi-functional rotary induction hardening machine tools: ① three processing stations operate independently at the same time (equivalent to three machine tools); ② During continuous quenching, the speed changes continuously without stopping; ③ It has the function of self correction when the three stations are not lowered in place and the turntable is not in place. Conventional numerical control system can not meet these functions, so we have developed a numerical control system based on industrial PC, which realizes the above functions by using thread technology under Windows 2000

the industrial PC host is the core of the system. On the one hand, it detects and controls all moving parts of the machine tool, on the other hand, it is connected to the workshop level network through cards, so that the system can use the remote computer to input quenching parameters and display the working conditions of the machine tool; PCI-1240 is used to control the speed and positioning of stepping motor, and detect various abnormal signals of stepping motor at the same time; PCI-1751 is a 48 channel TTL level parallel input and output board, of which 32 channels are set as input for operation button input, including start, pause and emergency stop buttons, manual heating, liquid spraying, rotation and switching of three stations, rapid forward and reverse rotation and slow forward and reverse rotation of turntable, rapid rise and fall of work pieces in three stations, slow rise and fall, etc; 16 channels are set as output, which is used for the enabling control of the turntable and the stepping motor of three stations. Pcl-724 is a TTL level input board, which is used to detect signals such as in place, lack of material, lack of water, and abnormal top. Because there is no level conversion and signal isolation function on the board, and the proximity switch level is 24V, pcld-785 is used as the input level conversion and signal isolation circuit; Pcld-885 is a 16 channel high-power relay output board with strong output driving ability, and the contact capacity is AC 220v5a; Pcl720 is a 64 channel switch input and output board, which, together with pcld-885, controls the switching, heating, liquid injection, plugging and tempering of each station

anti interference design

as the quenching machine tool is a special machine tool equipment, the high-frequency or intermediate frequency power supply used by the quenching machine tool has particularly serious radiation interference to electricity and other equipment due to the use of modulated wave output. Therefore, the control system adopts the following anti-interference measures

software design

system software design mainly considers the versatility, reliability and ease of use of soft plastic materials due to their lighter weight parts. To this end, the following issues are emphatically considered: ① the switching function when the three stations use the heating power alone and the three stations share the heating power; ② The software design of the three stations runs independently at the same time, and has various quenching functions such as simultaneous, continuous scanning, segmented simultaneous, segmented continuous scanning, etc; ③ It should be able to store more than 100 workpiece quenching programs, which is convenient for workpiece management and query; ④ It is convenient to input parameters without programming, and people who do not know computer can complete the input of workpiece parameters; ⑤ Help function, prompt at any time; ⑥ Fault self diagnosis and fault alarm prompt function

Figure 6 shows the overall block diagram of the system software design. After the computer is powered on, it directly runs the quenching program. "System initialization" includes the initialization of each board, calling the operating parameters of the workpiece run last time, etc., and distinguishing the position of the [auto/manual] button on the operation panel, and automatically switching to the corresponding main screen

after entering the main program, the system regularly checks the operation panel [automatic/manual (3) regularly check the accuracy of the hardness tester with standard hardness blocks, and it is never allowed to test on the support surface; the button states of [start], [emergency stop] and other buttons, and trigger corresponding events; In automatic state, the system mainly completes workpiece management, quenching parameter setting, turntable parameter setting, stepping motor acceleration setting and automatic quenching function; In the manual mode, the system mainly completes the manual operation of each station, the manual operation of turntable, the zero position setting of ABC three stations and turntable, the automatic zero return function and the manual parameter setting. The workpiece selection is completed in the workpiece management screen. After selecting the workpiece, the system first checks whether the parameter file of each station exists. If it does not exist, the parameter file name of each station is automatically created, and the operation prohibition flag is set, and a prompt is given at the same time. After the quenching parameters of each station are set, the system automatically cancels the no running flag. There is no program exit part in the overall block diagram. Software exit includes two exit methods, one is to return to the Windows2000 desktop, and the other is to directly exit the operating system, that is, shutdown

threading technology

since three stations run at the same time, the system sets four threads, three threads are used for quenching of three stations a, B and C, and one thread is used for indicating the running status of each station. The indexing of the turntable is completed by the main program; In the quenching process, in case of abnormal conditions, the system will immediately exit the quenching program and give an alarm. The abnormal condition of one station will not affect the operation of other stations; If the position cannot be lowered in place or the indexing of the rotary table is not in place, the system will automatically find the position

remote parameter modification

considering the cost problem, the program does not adopt c/s structure, and does not support remote ODBC. In order to support remote modification of quenching parameters, this software can be installed on the remote computer. After modifying the parameter file, copy the parameter file to the machine tool control computer, and then exit the application program on the machine tool control computer and run again

conclusion

the small induction heat treatment center is a nine position induction heat treatment center that integrates some key points of the international induction heat treatment machine tools in terms of compactness, flexibility, multi axis, production line, computerization, etc. it has been applied to the quenching and tempering of motorcycle cranks in several manufacturers in China, such as Luoyang north Yichu Motorcycle Co., Ltd. and the heat treatment plant of Qianjiang Group engine business department, In September, 2000, it was awarded the technology innovation fund for small and medium-sized enterprises of science and technology of the Ministry of science and technology, project code: 00C, and passed the technical appraisal presided over by Henan Provincial Science and Technology Commission in September, 2001. After expert testing, the repeated positioning accuracy of machine tool lifting is ≤± 0.03mm, the indexing positioning accuracy is ≤± 0.02 °, and the workpiece moving speed is 1 ~ 300mm/s. Compared with similar machine tools imported from a factory (one power supply with three quenching machine tools), the small induction heat treatment machining center is significantly superior to the imported similar machine tools in terms of function, price, structure, floor area, labor intensity of workers, processing efficiency, etc., and is equivalent to the imported similar machine tools in terms of fault diagnosis and protection. The machine tool prototype was exhibited at the Beijing International Heat Treatment Exhibition in October 2001, and was highly praised by insiders. (end)

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