在機械製造業中，降低成本是各家廠商追求的目標，傳統上在產品設計的階段並沒有將成本的資訊考慮進去，以致於無法即時改善設計降低成本。為了能在設計階段即得知成本資訊，本研究利用「作業基礎成本制」的觀念建立起一成本評估模式與程式模組，掛載在自行開發的電腦輔助設計軟體下，估算已參數化的減速機中重要零件製造成本，如傳動軸與齒輪。程式使用VB程式語言，透過API的功能，可與EXCEL中所建立的資料庫進行連結，使用者也可在程式介面中更動機台設定、刀具設定、成本參數以符合需要，各項設定完成後即可立即得知減速機零件的製造成本，可據此分析成本浪費的原因，以達到改善成本的目的。 本研究同時針對兩個案例來探討減速機成本的變化─第一個案例是在相同型號及輸入參數，但減速比不同的情況下，討論不同速比型號中各零件製造成本結構的變化；第二個案例是針對系列化減速機的不同零件加工成本變化，探討了案例設計中車床、外圓磨床及滾齒機的成本成長曲線。藉由此兩個案例分析可提供給設計者作為未來設計改善的參考。 Cost reduction is the goal that every firm in machine industry pursues. At the early stage of mechanical product design, the designers will not achieve the cost target, if the cost information is not available. The goal of this study is to establish a cost evaluation model based on “Activity Based Costing” (ABC) to get cost related information at the beginning of mechanical product design. The model utilizes a computer aid program, developed by Machine Design Laboratory of National Central University, to estimate manufacturing cost of parametric gear reducer’s parts. This program is written in VB language and associates databases established by EXCEL through API. Machines, cutters, and cost parameters are defined by users in the interface and then get the manufacturing cost instantly. Finally, this program could help us analyze cost-wasted factors for reducing cost. There are two cases illustrated in this study to get influence parameters of manufacturing cost. The main purpose of the first case is to compare manufacturing cost of two gear reducers and discuss the variation of cost structure. The two gear reducers with the same size but different gear ratios are discussed. In the second case, we discuss the production cost growth laws of the series gear reducer’s parts manufactured by lathe, cylindrical grinder, and gear hobbing machine. The analysis result of the two cases can offer some suggestions to the designers for the further design improvement in the future.
