Research And Development Of PMAC-Based Open NC System For Roll Grinder

The roll grinder is an indispensable important equipment in the industry, which grinds all kinds of dished or convex roller. For general roll grinder, its curves are mostly made by machinery structure. Due to its contour curves are few, precision is low and changing of curve parameters is difficult, general roll grinder cannot satisfy the need of product-manufacturing at present. With the rapid development of metallurgy, paper making, latex, plastic, printing and dyeing in the recent years, the technical need for roller grinding is being increased. With the popularization and application of NC, in order to accommodate the development trend of the precision, efficiency and automatization of roller grinding and to meet consumers' need and market change, it is necessary to develop a NC roll grinder. Moreover, with the development of computer science and micro-electronics, IPC-based open NC system has been an important direction of NC.To solve the difficult problem of roller grinding in manufacturing industry,considering the characteristics of roll grinder and the development trend of open NC system ,an open NC system of roll grinder based on IPC and PMAC is put forward, and both its hardware and software are studied. According to the characteristics and realized function of the roller grinding, the NC system of the roll grinder can control the movements of Z-axis, X-axis, C-axis, X1-axis and X2-axis, workpiece's running and grinder wheel's running. This NC system of roll grinder is made up of an IPC, a PMAC and its accessories, five AC servo drivers and motors, two DC transverters and DC motors. It is an open and modularization NC system, which realizes real-time movement control by PMAC, and background managing and man-machine conversation by IPC. The whole system is assorted with real-time and credible communications between IPC and PMAC in order to complete machining task. The IPC-based control software consists of man-machine interface application program, communication program between IPC and PMAC, motion programs and PLC programs. The communication between IPC and PMAC is accomplished by Pmac.dll . The motion programs and PLC programs are compiled and debugged by PEWIN, and are downloaded to PMAC and performed by functions in DLL (dynamic link library). The man-machine interface application program is designed by the modularization structure, and is developed by Delphi7.0. According to the hardware structure of NC system and consumers' need, this software includes eight parts: system initialization, machining parameter setting, machining process, measure, curve reappearance, grinding wheel dressing and compensation, PLC diagnosis and system help. It has been proved that PMAC-based open NC system can shorten development cycle and ensure high stability of system machining precision. The modularization structure of NC software has a very well flexibility,and is in favor of the extension of system function.