Clean-up tool path generation for combinatorial surfaces based on cutter center point of fillet boundary

摘要

The fillet is a typical transitional form for a region with a common edge between combinatorial surfaces of blisk parts, and the processing quality of that has a strong influence on the aerodynamic performances of the parts. As a special type, the incomplete fillet is generated due to missing data of the combinatorial surfaces, which is not tangent to the combinatorial surfaces. For machining the clean-up region with incomplete fillet, the planned tool path using the conventional method may result in excess residual material, which will affect the part performance. To address this issue, a novel clean-up tool path planning method based on the cutter center point of the fillet boundary is proposed. In this paper, the method constructs a mapping model from a point on the fillet boundary to the cutter center point. The model is solved with a point-searching algorithm so that the tool path of the fillet boundary can be calculated. Then, the region between the adjacent tool path of the fillet boundary is equivalent to circular curve for planning the clean-up tool path. Finally, this method is applied to the clean-up machining between the blade and hub of an open blisk using a computational simulation and experiment to verify its effectiveness. The results show that the maximum allowance is 0.311 mm with the conventional method, whereas it is approximately 0 mm with the proposed method, which satisfies the design requirement. Thus, the correctness and effectiveness of the proposed method are validated.