Research And Development Of WEDM Monitoring System Based On Windows

The Wire Electro-discharge Machining technology, as an important means of special type machining, is used more and more widely, especially in mould manufacturing field, it has become an important and necessary advanced manufacturing method. The high-speed wire electro-discharge machine (WEDM), which is an original electric machining facility created in China, is widely produced and used in China due to its simple structure, low price and low use cost. The high-speed wire electro-discharge machine in prior art employs the open-loop control system, and this means the output signals to the stepping motor can not be fed back. This structure is unsafe for machining.Aiming at the problem, a WEDM monitoring system is developed creatively in this paper by employing the object-oriented programming technology, on the basis of reference of relevant literature and a great deal of research. This system adopts the Windows operating system as platform, and employs the powerful VC++ as the development tool. In this paper, the key technology of the WEDM monitoring system has been researched. The main contents and results are as follows:1. According to the functional requirements of WEDM monitoring system, the whole hardware structure of the monitoring system has been established. Parallel port is selected as the communication interface between a machine and a PC, and the interconnection between the PC and WEDM machine has been achieved.2. According to the functional requirements of monitoring system, the system task is divided reasonably, and the multi-task processing in parallel of the monitoring system is completed by using the Windows multiple thread mechanism. The functional needs for the WEDM monitoring system are analyzed, and the function module is divided reasonably by using modular programming conception.3. In the design of the monitoring system, the monitoring of the control signal is achieved by using the high-priority monitoring thread, and the monitoring procedure algorithm and its program realization have been discussed; as a real-time periodic task, the acquisition of the parallel data is achieved with a multimedia timer. This timer can meet the real-time requirements due to its timing accuracy of 1 ms. This paper focuses on the use of multimedia timer and its program realization in this system.4. The parallel port application in the system, the format of 3B code, the decoding of the 3B and its procedure algorithm have been researched in this paper.5. The algorithm of interpolation-by-point comparison is researched, and on this basis, the WEDM simulation has been achieved.During the process of WEDM, this monitoring system can display the real-time machining path. When the distance between the actual machining path and the standard path is over than a set value, warning will issue and machine will be stopped immediately to prevent waste generated. This system also has the WEDM simulation function.Tested and used by Jinan Kete electric machining technology limited company, the system proves that the interface is friendly, the operation is convenient ,the system is easy to learn and use ,the performance is stable, and the system has a good application and popularization prospect.