Study Of Key Technology About Cam And Cnc On Impeller Five-axis Milling

Impeller part is the key component in the aviation, space ?ight and energy industryfield, its structure is complex and with high machining accuracy, is recognized as difficult-to-machine complex surface part.This paper countered the lack capacity of existing commercial CAD/CAM softwarein tool path planning, study cutting path planning strategy and machining processes, inorder to promote machining efficiency and surface precision. At the same time, this paperalso talked about the method of cutting path planning software development, make a goodfoundation for engineering applications.First, this thesis is devoted to the significant of this study, the complexity surfaceprocessing technology at home and abroad, describes the research results of ruled surfaceside milling and free-form surface end-milling. Next, the paper introduces the home andabroad research results in numerical control system, comparative study of a wide rang ofCNC high-level business functions, particulary, in-depth introduce the research results ofspline curve and surface processing in academic circles. Finally, quaternion theory andapplication which are used several times in this paper is also introduced.Ruled surface impeller are widely used in application, this thesis elaborates somekey technology about ruled surface impeller side milling algorithms, which includequadratic nonlinear equations to calculate cutter axis of side milling, compute cutter cen-ter of by dividing free-form surface into triangular plate, and use aided surface to programwhole cutting path. In addition, direct specific ruled surface impeller, promote 5-axisplunge milling rough machining method. According the geometric model of plunge, con-structed non-linear function to solve the row space and cutting step. Provided a novelsolution for the ruled surface impeller rough machining.In addition to the ruled surface impeller, with the advance in fluid dynamic calcula-tion method, freeform surface impellers is also more and more appear in the mechanicaldevice. The research of this thesis is based on an axial impeller which has been used in ap-plication, make a in-depth study for its CAD molding and CAM cutting path planning. Inthe CAD molding, B-spline local technology is used to promote the computing efficiencyof the intersection between freeform surface and hub surface. In the CAM field, param- eter filter method is used to the end-milling of freeform surface axial impeller, shortenedthe length of tool paths and improve the processing efficiency.Closed impeller is the most complex one in the impeller-type parts milling tool pathplanning. Direct at the existence of interference and collision problems, this thesis pro-motes a interference amendment algorithm. which includes the extract boundary of closedrunner, configuration space mapping, avoidance geometric programming, inverse C-spacemapping and so on, these algorithms are the core of closed impeller cutting path planning.For verifying the possibility of this algorithm, this paper build a cutting path for a closedimpeller's runner, the test result show this algorithm can avoid interference between cutterand part.In the spline interpolation of CNC system, this thesis pays attention to the lesspublished five-axis spline interpolator, according the special characteristic of quaternion,quaternion spline is introduced into the controlling of rotation movement of five-axis ma-chining, spline interpolator is developed. Expended the G code of ISO NC codes, devel-oped five-axis spline interpolator in open CNC system, and analyzed the performance ofsuch interpolator, used this interpolator to finish a impeller-typed parts machining.In the end, according to simulation and actual machining, verified the correctnessand feasibility of the tool path planning methods. this thesis shows the actual process-ing pictures of experiments, which include ruled surface side milling, freeform surfaceend-milling, plunge milling of impeller parts and blade finishing of five-axis spline inter-polator. From the machining process and milling results, the development algorithm canbeautifully finish the milling of many forms impeller, the promoted plunge milling algo-rithm is also a feasible impeller rough machining process. At the same time, the bladefinishing quality which machined by five-axis spline interpolator is better than traditionalfive-axis linear interpolator, the test results show the five-axis interpolator has a certainpractical value in engineering.