The concerned parameter of chain link of transmission of machine tool machinery (wait like journey of lead of speed ratio, guide screw, limit and pulse equivalent) all store with the form of machine tool data in the memory in numerical control system, to controlling a system character, the numerical value that changes data of machine tool of some feed axis was equivalent to changing chain link of transmission of machine tool machinery the structure of relevant section, because servo electric machinery is actual,the feed axis structure of drive was not changed, do not exist actually with the feed axis of the correspondence of place of machine tool data after altering namely, friend call his " fictitious axis " . If be opposite in numerical control program " fictitious axis " process designing, criterion actual feed of the axis is not the true feed of drive of place of electric machinery of the servo after the program is carried out to be worth for actual process designing, both between put in one scale relation. For example: The guide screw lead of axis of feed of some of numerical control machine tool is 40mm, now data of its machine tool by 80mm of instead of former numeric 40mm, be equivalent to one lead is 80mm " fictitious axis " implicative at servo electric machinery later. In numerical control program process designing makes this axial feed 80mm, servo electric machinery will turn 1 round (hypothesis speed ratio is 1) , the is linked together actually with servo electric machinery true guide screw in transmission catenary also will turn 1 round, its lead is 40mm, the feed of reason workbench is 40mm, the feed in such programs was compressed equably half, both the scale relation between is 2. If Sreal is a machine tool lead of actual join guide screw, svirtual is lead of fictitious axis guide screw. When machine program of curve of work out ellipse, according to the equation of elliptical curve, take axis of feed of some of modification machine tool the machine tool data of relevant section, can come true to magnify or be compressed of axial direction here, the circle that finish arrives to alternate elliptically, realize the CNC Machining of elliptic spare parts. If pursue,method of 3 process designing sets the ellipse that requires treatment 3 in (1) place is shown, long, short axis is 1500mm and 750mm respectively, what use X of numerical control machine tool, Y the guide screw lead of two feed axis is 40mm, press a circle (2) process designing, should take X axis to be fictitious axis, the lead that establishs its guide screw is 80mm. The cent of process designing job of CNC Machining is the following two parts: (Basis of data of 1) modification machine tool document [9] , axis of machine tool X the following 6 groups in all data of 10 machine tools enlarges 2 times: 1. MD11, of MD12 pulse equivalent 2.
MD27, MD28 acceleration, decelerate spends 3.
MD31 feed axis top speed 4.
MD20, MD21 is lost, to soft limit 5.
MD6, MD36 winds reference point eventually, initial velocity 6.
of coordinate of MD3 reference point (2) writes CNC Machining code according to document [10] definition, use " fictitious axis " the process designing of part of code of treatment numerical control that the method undertakes elliptical curve is as follows: Fast feed of 6(of ＝ of M1 of of Y0 of X1500000 of of N01 G00 comes treatment start) of F6000 of I1500000 of of G17 of of G02 of of N05 (the full circle that undertakes radius is 1500mm in order to be versed in speed of advance is spent is machined) of X200000 of of G00 of of N10, return) 30 of ＝ of M1 of of N15 (the program ends) graph 3 workpiece pursue 4 last words the article introduced to use " fictitious axis " concept, the method of a kind of manual process designing that implements elliptical curve treatment on the numerical control machine tool that has structure of half closed circuit. This method already used a success in effective system. With other ellipse process designing method compares curvilinear handiwork, have precision the good point with tall, simple process designing, and have certain versatility; Insufficient place is this method needs to alter data of partial machine tool, handlers needs to have professional knowledge. This method applies to machine tool of the servo of open loop position that serves as executive component into electric machinery with the pace numerical control likewise. CNC Milling
CNC Machining