Online error compensated a technology to receive wide application in accurate turning treatment, but the application in bore hole is very few still, it is scarce more in the boring treatment in deep alveolus especially. Machine methodological photograph to compare with turning substandard surface, the rigid limitation that the external diameter dimension of lever of the boring when boring hole is bored hole, those installation detect in the error on lathe tool carrier sensor and use pair of machining error to undertake compensatory carries out component, because its volume is larger, disadvantageous or cannot install go up in boring lever. For this, the article puts forward the lever of fine tuning boring of a kind of new-style structure, make online error compensates a technology to be able to get applied in boring treatment. The place of 1a of composition of a picture of small feed machine in turning treatment shows the structural sketch map of the jiggle tool carrier that develops for Japanese Osaka university, sensor of the pottery and porcelain that suppress report is used to make component of small feed drive in this tool carrier. The structural sketch map of the small feed tool carrier of the drive of sensor of the pottery and porcelain that suppress report that graph 1b is development of Harbin Institute of Technology. Graph the small feed tool carrier of drive of the 1 pottery and porcelain that suppress report tool carrier of afore-mentioned feed of two kinds of minim are the error in be being machined with outward appearance turning on compensation device, the pottery and porcelain that suppress report (PZT) sensor and cutting tool outfit are in same go up point-blank, because press sensor of electric pottery and porcelain longer, make these small feed device is compared in the dimension of direction of cutting tool feed big. The structural design of boring lever is when boring is small and deep aperture, the diameter of requirement boring lever is small and length is longer. If the graph is shown 2 times, designed the staff of fine tuning boring that by two lever of coaxial inside and outside comprises one kind. Among them, lever does control to use outside, call control staff, control lever make it with flexible the lever structure that hinge is fulcrum, boring cutter and sensor of the pottery and porcelain that suppress report install the two end that dominating lever respectively. Lever uses the small displacement error that checks boring cutter inside, call test staff, test lever designs cantilever form, the one end that tests staff is secured in tool carrier on, the means of hinge of another Duan Yirou sex and boring cutter and control lever connect together, through be being stuck in the meet an emergency of fixed end piece of the lever inside the test be out of shape the radial deflection error that will monitor boring cutter. The boring lever of form of this kind of double lever sensor of pottery and porcelain of press press report and small displacement check the effect of sensor and need not make boring shank diameter is done lesserly, and length also can be done longerly, machine deep alveolus in order to facilitate. Graph lever of boring of fine tuning of sketch map of structure of lever of boring of fine tuning of 2 pairs of lever is online compensation system is main composition and working principle use closed circuit to compensate pilot means to raise boring to machine precision. If the graph is shown 3 times, lever of fine tuning boring controls a system to basically comprise by the following parts: (Lever of boring of 1) fine tuning (include to control lever and test lever) , (Part of instrument of 2) meet an emergency, (3) PZT sensor reachs share of drive power source, (4) controls the computer. In the graph 2 in, when decrescent of boring force FC, boring cutter will be down deflexion, test lever also is down deflexion. The signal that measures by instrument of meet an emergency is reduced, this chronometer calculates the signal that machine output increases to give PZT sensor drive the system, PZT sensor is stretchy drive control lever to circle flexible hinge fulcrum clockwise rotates, the deflexion that such boring cutter are down was compensated. Same, greaten when boring force FC boring cutter up when deflexion, the input voltage of PZT sensor is reduced and shorten, control lever to anticlockwise direction rotates and compensate boring cutter up deflexion. Bore hole in nicety then in machining a process, the compensation action of the PZT sensor that can adopt system of staff of fine tuning boring raises treatment precision effectively. Graph compensation of online compensation system controls lever of boring of 3 fine tuning the model amends control to undertake closed circuit effectively, must undertake to machining error online detect and compensate in real time, and uses compensation control method wants to be able to compensate systematic error not only, and can compensate random error even. Forecast compensation controls a technology (FCC) is a kind of very efficient control way, law of this kind of control treats machining error as is alignment of a group of time will analyse, the error that can compensate repeatability not only and still can compensate random error. Forecasting compensation to control main good point of the technology is to need not study sundry complex error source is right the influence of machining error, and the dependency that can use error alignment oneself directly, according to already measuring gotten error the value forecasts the error of below one hour effectively to be worth. To undertake to boring machining error real time is compensated, the small displacement error of boring cutter can express with following AR(autoregressive) model: Among them Yt states boring cutter is in the small displacement error of T hour, fj (j= 1, 2, . .
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) it is to return to parameter oneself, d is white noise, the does not return to random portion in representing error series (here also included test error) . As treatment undertake, the model parameter in AR model is ceaseless by new collection information place is amended, make random model can convey boring machining error correctly from beginning to end so. Forecasting compensation to control a of the technology main characteristic is can right machining error undertakes real time forecast, the AR model that measures error value and place always engrave to build with present tense before the basis will forecast in the future the error of hour. After forecasting an error ahead of schedule so, won time to compensate machining error in real time. The basis is formulary (the error that 1) can get shifting to an earlier date Q pace forecasts is worth as follows: What this system uses is to shift to an earlier date the AR(3) model of one pace. Graph the 4 effect sketch map that gave out to use this kind of model to have forecast, the forecast value that can see machining error from inside the graph and real value are very adjacent, can satisfy requirement of compensatory of the error in accurate boring treatment. Graph experiment of graph of effect of forecast of 4 machining error considers to emulate an experiment to compensate function to decide the trends of system of staff of fine tuning boring, the method that uses emulation test undertook study to boring staff system. Drive boring cutter to come with an oscillator imitate cutting process. When the vibration that produces frequency of a group of change when oscillator, the trends that tests system of staff of fine tuning boring compensates function. If the graph is shown 5 times, by 5Hz when oscillatory frequency change arrives when 40Hz, the boring cutter that arrives with oscillograph observation is in have compensation and the displacement case that without compensation the condition leaves, among them the case of 1 boring cutter displacement that expresses to did not compensate a condition to fall, the cases of 2 boring cutter displacement that express to compensation condition falls. The compensation frequency that can see from inside the graph system of staff of fine tuning boring can be effective is 40Hz or the following dynamic error. Graph graph of effect of forecast of 5 machining error pursues experiment of boring of 6 treatment result is in numerical control lathe (on MAZAK QUICK TURN 8N) system of online to lever of fine tuning boring compensation undertook the experiment studies. An internal diameter is machined to be 35mm in the experiment, deepness is the aperture of 160mm, workpiece material is Al, lathe rotate speed is 500r/min. Be compensated to using below similar cutting requirement and did not use compensatory circumstance to have a test, the circularity that checked the aperture that the treatment below these two kinds of circumstances comes out with circularity appearance (if pursue,show) 6 times. Can see from inside the graph lever of fine tuning boring is online the improves work treatment precision with compensation can effective system. Conclusion was developed new-style the lever of fine tuning boring of double lever structure compensates a system, came true to undertake an error to small and deep aperture online detect and compensatory nicety is machined. The method that uses time alignment analysis undertakes building model and forecast to boring machining error, the experiment shows this kind of forecast compensates a method to be able to raise boring effectively to machine precision. CNC Milling
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