Grind treatment precision control and null to survey a system

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Summary: Put forward a kind to use personal computer to build modular forecast to raise the method of precision of round grinding treatment inside bearing ferrule. Introduced to grind treatment precision control and null to measure systematic composition and working process, this system will be measured in treatment measure organic union with treatment hind, what can control dimension of bearing ferrule internal diameter effectively is dispersive degree, raise treatment precision significantly. Keyword: Grinding machines null to measure precision to control the Accuracy Controlling And Zero-position Measuring System For GrindingDong Mingli Et AlAbstract that build a model: A Method For Improving The Grinding Accuracy Of Bearing Races By Computer Model-building And Forecasting Is Presented. The Composition And Working Process Of Accuracy Controlling And Zero-position Measuring System For Grinding Are Introduced. Combining In-process Measuring With Sorting Measuring, this System Can Control Effectively The Dispersion Degree Of Inner Diameter Sizes And Raise Greatly Machining Accuracy. Keywords: 　 of 　 of Grinding Zero-position Measurement Accuracy Control Ling Model-building 1. Foreword is in batch grinding treatment, because each respect such as machine tool system is complex the influence of the element, those who make machine the spare parts on size error that come out to have certain is dispersive degree, should spend dispersedly bigger and when exceeding treatment to allow an error, can appear a certain quantity of parts returned for repair and reject. The dimension that controls treatment part is spent dispersedly can use different method. Although be measured actively it is a kind of when reduce grinding to machine dimension out of tolerance method that uses extensively, but the element that machines precision as a result of the influence is many sided, have the factor that measures instrument and itself of treatment machine tool actively already, also have the factor that machines the interference such as environment and condition, and determine these elements often very difficult, use the outcome that measures income actively so not very ideal, this makes measure the application in grinding treatment actively to have certain limitation. Of article introduction grinding treatment precision control and null measurement technique is the grinding in the aperture inside bearing ferrule in machining a process, the cleanness of bearing ferrule classics after will measuring grinding actively to machine handles evacuation to enter automatic and grading machine have measure grading with error statistic, get the series of on size error of bearing ferrule internal diameter of an orderly disperse, use this alignment to be worth the mathematical model that builds character of system of a report, undertake to model feature parameter online differentiate, use this model to forecast the value of on size error of next work next, and give out feedback of signal of error correction control arrive to measure a system actively to compensate machining error. Such active measuring instrument and automatic and grading measure in machine, treatment measure organic union to rise with treatment hind comprised " null surveys a system " , realized temperature thereby, be out of shape and the compensation of dynamic error, rose to measure systematic dependability automatically greatly, the dimension that controlled bearing ferrule internal diameter effectively is spent dispersedly, rose to machine precision. 2. Systematic composition and working principle grind treatment precision control and null to survey a system by the circle inside bearing ferrule grinder, inside the circle is ground measure actively automatic and as grading as control equipment, bearing ferrule machine and by 8751 sheet piece the intelligence that aircrew becomes grinds treatment precision to dominate real time online build a model. This system block diagram is shown 1 times like the graph. Graph 1 grind treatment precision control and null to measure the circle inside classics of grinder of the circle inside ferrule of bearing of systematic block diagram to grind measure actively undertake machining to workpiece with control equipment, classics kibble, essence is ground, after foreword of smooth grinding work, treatment gives final finished product. The cleanness of finished product classics after treatment and fluctuation makings orgnaization transmit bearing ferrule automatically automatic and grading undertake metrical on machine workbench grading, personal computer system is right automatic and grading the measurement of machine information undertakes collect and be handlinged, real time is built grind treatment precision to control a model. Through online differentiate distributinging differentiate of systematic feature parameter and error and availability differentiate, make the model reflects systematic feature well and truly. The forecast of next work error that forecast control system issues according to the model controls a quantity to accuse a system to issue control signal to grinding treatment system via be being measured actively, control the feed of emery wheel via actuator, obtain the optimal control to machining process, implementation null is measured. 3. Precision control means and subordination of department of control of precision of the machining that build a model are inputted at how (speed of feed, cutting) , much output (dimension precision, appearance precision) control system. If will a lot of element considers along with all the others, because very complex, computation measures systematic equation,meet great and have real time hard online control. If processing a system,model of a fixed control is introduced below stabler circumstance, through online differentiate systematic feature parameter, the model can reflect systematic feature well and truly, forecast control effect is better. Grinding of the aperture inside bearing ferrule machines a system to attribute this kind of situation. In grinding process, although grinding speed can choose appropriate numerical value according to experience, but the interference as a result of noise, work measure still often out of tolerance. Accordingly we regard this system as an odd input (feed) , only output (work measure precision) control system, through the comprehensive information that obtains machining error is being measured after treatment. According to alignment of error measured value, systematic model expression is Y (K) ＋ A1y (K - 1) ＋ ... ＋ Any (K - N) ＝ B0u of 　 of 　 of 　 of 　 of 　 of 　 of 　 of 　 of 　 of 　 of 　 of 　 of 　 of 　 of 　 of 　 of 　 of 　 of 　 of 　 of 　 of 　 of 　 of 　 　 　 (; U (K) the input that is systematic K hour; ε (K) for white noise; A1, A2... An, b0, B1... Bn is model parameter. What machine as a result of grinding of the aperture inside bearing ferrule is characteristic, the system did not export delay time, (1) type can express to be Y again (K) ＝ Bou (K) ＋ B1u (K - 1) ＋ ... ＋ Bnu (K - N) 　 　 of 　 of 　 of 　 of 　 of 　 of 　 of 　 　 　 - A1y (K - 1) - ... , general (2) both sides square takes type to all be worth E [Y (K) 2] ＝ E ｛ [Bou (K) ＋ ... ＋ Bnu (K - N) - A1y (K - 1) - ... 　 of 　 of 　 of 　 of 　 of 　 　 　 , reason (3) type right is the 2nd times 0, the 3rd incontrollable. Be about to make E [Y (K) 2] for the smallest, make the first only for 0, reason is arranged get the smallest variance to be 　 U from corrective control model (K) ＝ [A1y (K - 1) ＋ ... ＋ Any (K - N) - B1u (K - 1) - ... - Bnu (K, reason takes no account of systematic input, be in namely (4) make in type ＝ of B1 ＝ B2... ＝ Bn ＝ 0, your β of ＝ of 1 ／ B0, the model forecast of system of treatment of grinding of the aperture inside bearing ferrule controls formula to be U (K) ＝ β 0 [A1y (K) ＋ A2y (K - 1) ＋ ... ＋ An (K - N) ] 　 of 　 　 　 (5) the Y in type; N is model rank number; U (K) for K the forecast of workpiece controls an amount. Evaluating the differentiate basis that controls effect stand or fall is bearing ferrule automatic and grading opportunity is right the measured value of on size error of each spare parts after treatment. To the integral performance of systematic work circumstance the evaluation can use the method that CP of computational project coefficient is worth, CP value can reflect the condition of error distributinging center and coincide of tolerancepublic errand center, its computation formula is 　 　 (6) the T in type is quality standard or allow is differred, σ is standard deviation. After tolerancepublic errand limits is certain, or when set dimension spends index to be worth for T dispersedly, begin K from treatment workpiece hour, classics is automatic and grading machine is grading measure and operation statistic, attainable CP (K) with σ (K) value, can mirror a dimension inside this time area to spend a circumstance dispersedly thereby. use control the system is mixed did not impose control the CP computation value that two kinds of circumstances leave same time limits undertakes comparative, can get dominating control result of the system, namely 　 　 (7) ＜ of 0 ＜ S 1 when control is effective, control otherwise invalid. 4. Electric what grind treatment precision control and null to survey a system with principle of work of personal computer system is electric be like a graph with block diagram of principle of personal computer system 2 are shown. Graph 2 electric with block diagram of principle of personal computer system this system with 8751 sheet piece machine for core, patulous clavier reachs indication interface the 8279 input passageways that serve as man-machine interaction, key in corresponding command and data, 8 LED monitor is used at showing parameter, information of feedback system work. Automatic and grading machine use differential inductance sensor to undertake osculatory metrical to machining the bearing ferrule after, work measure deviation changeover becomes telegraphic name. Use signal to magnify this plants Ji Xiangmin demodulation traditional and effective communication bridge measurement unit, cooperate MAX180 of converter of D of ／ of 12bit 　 A to undertake collection to data of measure of the work after treatment, changeover. Memory of program of 8751CPU embedded 4KB, be in charge of data operation, treatment and processing, build in real time grind treatment precision to control a model, via error distributinging differentiate and differentiate of diagnostic parameter availability, give out next work error to forecast control signal, via expanding converter of D ／ A is changed, in sheet piece workpiece error forecast control measures output to arrive to be measured actively below engine system control control a system, in order to adjusts the feed that grinds treatment system. The system is used but curve of the parameter that the patulous unit of erasure EEPROM28C64 memory stores need is saved for a long time, data, statistic and form, these save information to still can pass clavier input to undertake modification at any time. TP μ P16APE uses miniature printer at printing curve of data result, experiment and form. Canal of two-way brilliant brake drives photoelectricity implementation of canal of power brilliant brake is automatic and grading machine fall the open movement of makings chamfer, the dimension of ferrule of the bearing that finish in group. Use monitoring of WATCH 　 DOG the moving circumstance of system of whole personal computer, when the program changes PC hand because of interference, system instantly restoration makes corresponding processing. 5. Conclusion is grinding treatment in the system, use personal computer to build a model to forecast control, the measurement unit after will grinding treatment to measure control system and machine actively (automatic and grading machine) be united in wedlock, implementation null is measured, developed model pilot to use range greatly, rose effectively to machine precision. Especially system of grinding of the circle inside relatively complex to influencing factor bearing ferrule, grind treatment precision control and null to measured a system to achieve the forecast that round grinding machines the feed in the process inside bearing ferrule, amended temperature, emery wheel and other effectively the influence that complex element machines precision to workpiece. The experiment proves, grinding treatment precision control and null to survey a system is accurate and a kind of effective that controls precision of grinding of the circle inside bearing ferrule, reliable method. CNC Milling CNC Machining