- 期刊
應用圖形技巧於具有公差規格之旋轉加工件來進行製程規劃
Graph-Based Process Planning for Rotational Machined Part with Tolerancing
摘要
本文探討具有公差規格的旋轉加工件之製程規劃方法以及圖形表示模式，並由圖形表示方法與推演技巧來降低圖形結構的複雜度，進而以公差表摒除不符合設計規格之製程。此法首先依工件表面之幾何特徵與尺寸公差規格來決定可行之最終加工方式，而根據各可行之最終加工方式反推其前加工順序，再以圖形表示出所有可能之製程，而構成樹狀或森林狀結構，應用相同加工特徵面具有同一之加工順序可合併與刪除特性來降低圖形結構之複雜性，把精簡所得之可行製程以公差表進行分析其公差累積量是否符合原設計規格要求，捨棄不符設計需求之製程。文中以一階級圓桿加工為例，驗證說明此方法與模式，應用此法的價值在於採用一致性之圖形來表示模式與推理。
並列摘要
This paper investigates a methodology and corresponding graph modeling of process planning for cylindrical machined parts with tolerancing. Methods and techniques for representing possible process plans, reducing the complexity of the graph, and eliminating over-toleranced plans are developed. The method first maps each feature of a part into feasible finishing processes that are capable to achieve the specified tolerances associated with the feature. All possible process plans are then developed by expanding preceding processes of each finishing process. The expanded processes form a graph, or a forest, with processes as nodes and process sequence as links. Processes with same specifications can be further merged and pruned to reduce the complexity of the graph. Tolerance stack-up of each possible plan for simplified results is also further computed by tolerance chart such that over-toleranced plans are eliminated. As there are often many feasible plans for machining a part, the qualified plan that satisfies design specifications is achieved by traversal through the graph imposing tolerance chart. An example is also demonstrated to illustrate the approach and the model. The merit of this method is to employ a unified graph model for representing and reasoning.