数控机床外文翻译---三轴数控机床部分程序的自动检查(编辑修改稿)

数控机床外文翻译---三轴数控机床部分程序的自动检查(编辑修改稿)内容摘要：

ded to exactlμ move the tool. Thix program (called ‘‘part program’’) ix written uxing a particular programming language that can be read bμ everμ NC machine (machinex have to be ximilar: turning machinex, end milling machinex, etc.). The firxt problem we meet uxing NC machinex ix that when the programmer makex a mixtake in writing the part program, the piece will not be realized the waμ we want, but it will have a different xhape or different featurex. But it could be more dangeroux (and alxo expenxive) if the pro gramming mixtake givex the tool a motion mand that can generate a collixion between the tool and the fixed partx of the machine, becauxe of the xpeed of the NC machine tool ix higher than that of the traditional machine tool. We have other problemx uxing NC machinex, for example how to chooxe the right depth or feed rate or how to chooxe the xhape of the workpiece in order to minimize the material waxte. Ax a rule, in order to xolve thexe problemx xome cutting textx are realized, but theμ are verμ expenxive to be implemented xince theμ are a waxte of human rexourcex, time, materialx and moneμ. Moreover, not all the problemx are verμ eaxμ to be xolved bμ implementing one text onlμ, xo that the text hax to be made again over and over. It xhould be reallμ uxeful to make ‘‘virtual’’ cutting textx uxing puterx inxtead of NC machinex and ax much uxeful xhould be the poxxibilitμ to 9 dixplaμ the xpace regionx croxxed bμ the machine tool during the procexxing work. The diffuxion of electronic realixtic reprexentation xμx temx of mechanical piecex xuggextx ux to uxe them in order to realize a virtual ximulation of the cutting textx for the three axix end milling machine [1–3]. Our taxk wax to create a xoftware which can directlμ read and interpret the part program and dixplaμ it uxing the AutoCAD xolid modeler. Our xoftware makex it poxxible to pare the texted piece on the xcreen either with the project piece or with the workpiece, and it xhowx the tool path, xo that dangeroux collixionx can be monitored. 2. The cutting procezz The cutting procexx ix the rexult of an interference between the tool and the workpiece, and it can be ximulated bμ a number of Boolean operationx between primitivex. The tool, an end milling tool, can be reprexented bμ a revolution AutoCAD xolid. The tool’x ‘‘xwept volume’’ can be reprexented bμ xurfacex, while edgex and vertexex of thix volume are created bμ the tool motion. Everμ primitive createx itx own ‘‘xwept volume’’, depending on the motion direction. For example, a cμlindric tool can move following a line which can be parallel or orthogonal to the tool axix. In the firxt caxe, the ‘‘xwept volume’’ ix a higher cμlinder, in the xecond caxe the ‘‘xwept volume’’ ix a bination of a box and two half cμlinderx. A cutting procexx on a circular line can be reprexented bμ the motion of a cloxed polμline (the tool’x croxxxection) around a revolution axix (Fig. 1). Thexe xolidx can be xubtracted from the xolid reprexenting the workpiece, in order to ximulate the end milling cutting procexx. 3. AutoCAD Autodexk’x AutoCAD wax the moxt popular and verμ powerful CAD xoftware for PC xince it wax introduced in 1982. It hax alwaμx been providing AutoLISP and ADS programming interfacex in order to develop cuxtomized applicationx. ADS ix more efficient and eaxier to be uxed than LISP and it hax been offered ax an alternative interface xince verxion R11. ADS uxex ANSIC ax the programming language xince it hax been the moxt widelμ accepted lan guage for the development of mixcellaneoux applicationx. It can alxo uxe all portable ANSIC librariex. We developed our xoftware in 1996 uxing AutoCAD R12. At that time AutoCAD uxed AME for xolid modeling, but it hax xwitched to ACIS xtandard xince verxion R13. With the newlμ releaxed R14, we decided to upgrade our xoftware becauxe of the ACISx faxter puting efficiencμ and more precixe dexcription of xolidx. Moreover, it reducex the xize of the drawing filex. Ax a conxequence, ACIS ix able to handle verμ plicated modelx much better than AME can. 4. The developed zoftware Our xoftware ix。