Papers by Keyword: NC Machine

Abstract: Based on Windows operating system, the software of NC machine’s On-line inspection has been developed, the key technology in software development: Set up the comprehensive error model of the inspection system, probe error treatment technology, communication etc. Utilize this software to turn into the procedure of measuring automatically, and can compensate to probe error, the geometric error and thermal error of the machine, have improved the precision and efficiency.

Abstract: Normal circular-arc spiral bevel gear is a new type gear based on Bertrand conjugation principle. Normal circular-arc bevel gear selects directrix on the basis of paying attention to machining planning process. When the directrix serves as loxodrome, the formed tooth profile surface not only has fine transmissibility like general arc bevel gear, but also is convenient to machining. Starting with differential geometry, the geometry nature and inner relationship of Bertrand conjugation surface are studied. Then the normal circular-arc surface id put forward which is a typical Bertrand surface; the conjugation theory of loxodrome normal circular-arc bevel gears is studied. The characters of loxodrome line are analyzed. The tooth profile of loxodrome normal circular-arc bevel gears, the primary condition the directrix line must be satisfied, the relative curvature of the conjugating surfaces, the relations between non-interventional condition and curvature axle of the directrix line is provided; the NC machining theory of normal circular-arc bevel gears is studied, including the designing and manufacture of the tool, the movement of the machine, the adjustment of the tool under the condition of tangency and non-interventional condition and so on.

Abstract: Interfenrence detection is a crucial problem in the process of the stationary internal toroidal gear machining. This paper proposes a new method to detect interference regions in 3-axis stationary internal toroidal gear machining. With this method,numerical control machining geometric model is built to detect interference. Interference regions can be identified effectively by comparing intersection point between detecting line and spiral tooth flank with that between detecting line and tool sweep. It was found that this method not only can be used to detect local interference regions but also global interference regions according to whether dectecting line and not processing area of curved surface have intersection point.

Abstract: NC machines touch-trigger probes generally have three-dimensional measuring function, its working principle is equivalent to a duplication of contacts with high precision switch, under the control of the measurement software, to achieve high-precision machining center automatically detected. Paper proposed based on BP neural network in NC machines tool probe measurement error parameter identification method. Through theoretical analysis and experimental research to determine the probe installation error parameters and the probe measurement error parameters of the model, but also identify ways to eliminate probe system error term uncertainty of the condition, in order to determine the detection method and planning of testing provides a reliable path basis.

Abstract: Since the widespread application of NC machine, fault diagnosis and repair of NC machine has been the subject of attention. Now both at home and abroad has a number of new concepts and methods to the field. The application of CBR technology in NC machine fault diagnosis analysis system is a very good exploration and research. Application of CBR technology is based on similarity of NC machine failure, using the method of case-based reasoning to identify the reference case, diagnosis method with reference to the case to find a reasonable solution. The CBR technology is applied to diagnose faults of CNC system, the accumulation of collection is convenient for the experts' experience, the fault diagnosis analysis system is more practical.

Abstract: The thermal error of main-shaft is the main factor that effects the machining quality and efficiency of NC machine. The modeling of thermal error of the main-shaft is significant. There are a lot of methods to build the model. The method of least squares support vector machine has good effect on non-linear system and make the model have good decision-making ability. In this paper, the temperature field of the main-shaft is sampled and the important parameter and is optimized in a wider range when modeling with the least squares support vector machine by using grid searching method on the Matlab platform. In this way, the modeling accuracy is improved effectively.

Abstract: The standardization of the tools cutting parameter in NC machine is studied. The organization scheme of tools information in database, tools code, the intelligent selection of tools and machine parameter are analyzed. Tools database are built up

Abstract: The machining accuracy is greatly affected by the precision of mechanical transmission of the NC machine. Through analyzing the nonlinear factors of mechanical transmission components of the NC machine, the reasons for affecting the positioning accuracy and the contour- following accuracy are obtained. Therefore the methods of improving the positioning accuracy and the contour- following accuracy are put forward.

Abstract: Traditional PID control has not been able to meet the control requirements. This paper has designed one type of Fuzzy PID controller to use in NC Machine Servo System. Simulate the response of Fuzzy PID controller and traditional PID controller by Simulink in MATLAB. The simulation results indicated that the Fuzzy PID controller had quick response speed, strong robustness, high precision and non-overshoot etc. It improved the whole control performance of NC Machine Servo System.

Abstract: On the basis of compliant polishing device for aspheric, a new method of bonnet polishing on magneto-rheological of torque servo driver has been proposed. It has introduced the bonnet polishing composition and polishing principle. Polishing tool using the flexible bonnet, it can better adapt to the different curvature change of parts, and the stable polishing force can be get through MRT. Combining the constant torque device on MRF with CNC machine, this embodies high rigidity, higher precision of NC machine and reflects the MRT with adjustable, controllable, rapid response characteristics. The formulae of stress and relative velocity of polishing are deduced, and the material removal rate model has been set up. The experimental results show that this new method of bonnet polishing can provide stable polishing force, and the model is correct, has good prediction ability.