- 學位論文
改善手工具品質的穩健設計實證
An Empirical Study Via Robust Design to Improve Quality of Hand Tools
摘要
TRIZ (Theory of Inventive Problem Solving)是現今產品創新發明與改善中，解決瓶頸技術的極佳的方法；AHP (Analytic Hierarchy Process)是現今決策領域中常見之決策工具，主要是對可能影響因素決定其權重及排序來進行改善。本研究以鋼鐵手工具製造為實證案例，分別藉由TRIZ與AHP由作業流程中找出影響製程的參數，再以六標準差的DMAIC流程結合田口的穩健設計來改善品質，並由實驗結果比較TRIZ與AHP所挑選出的製程參數。 套筒是佔手工具出口值最多的品項，對於套筒可承受之硬度與壽命一直為高品質化之評估指標之一。而套筒的加工流程，在所有流程中影響品質的關鍵因素為熱處理製程，所以熱處理之特性對於手工具套筒的硬度質亦扮演重要角色。在手工具熱處理流程中，硬度為一項重要的品質指標。硬度不足會造成套筒容易磨損，而硬度過高在使用時容易造成脆裂，因此本研究之目的有四： (一)透過TRIZ與AHP兩種不同的方法由作業流程中找出影響製程之參數。 (二)將上述二種方法所選出之影響製程參數作為田口品質工程的實驗因子，再結合六標準差的DMAIC步驟來嚴密研究流程。 (三)由實驗結果比較TRIZ與AHP所挑選出的參數，對最佳化製程的差異。 (四)比較TRIZ與AHP工具輔助挑選實驗因子之差異。 最終實驗結果顯示AHP與TRIZ所挑選出之實驗因子組合有三個因子完全相同，相異之因子對於SN比與平均數皆沒有顯著影響，由此判斷即使兩工具挑選出的因子有些許差異，但對實驗結果的影響並不顯著。 AHP與TRIZ因子組合經確認實驗結果得到，能夠有效提升Cpk值，從原本0.69提升至1.38與1.51，確實均能夠改善品質精度，顯示無論是AHP或TRIZ結合田口方法對作業方法的改善及品質的提升都會有相當的助益。
並列摘要
TRIZ is a very good method to solve the bottleneck techniques in the current product inventing and improving；Analytic Hierarchy Process is a common tool for decision-making, mainly is to find out the possible effect factors and base on the percentage and priority to do the improvement. This research is proceeded as an experiment-based one which takes the manufacturing procedures of steel hand tool in a certain transnational corporation as an example, by using the TRIZ and AHP to find out the factor that might effect the operation process, combine with the 6 Sigma’s DMAIC process with the Taguchi Method's robust design which can reduce the variation causes and can minimize each kind of the variations in order to make the products the least sensitive to the variation causes, is a good way used in the industries to improve the processes and upgrade the product qualities, and according to the result of the experiment to compare the factor in the product process that led by the TRIZ and AHP. Sleeve is the top one of export value item, the hardness and the life-span have always been one of the important indexes to judge a sleeve’s quality. In the manufacture process of sleeve, heat treatment process is the key factor that may affect the quality of product, therefore, the heat treatment process is good or bad will take an important roll of the hardness of sleeve. In the hand tool heat treatment process, hardness always has been the important index of the quality. When the hardness is insufficient, the sleeve may easily get wear and tear, but if the hardness is too high, then the sleeve may easily get cracked during the operation, thus in this research, we have four purposes; 1.By using the TRIZ and AHP two different methods to find out the factor that may affect the product process. 2.Take the above mentioned factor as the Taguchi Method's experiment base, then combine with the 6 Sigma’s DMAIC’s phase to study the research toughly. 3.Compare the result of the experiment with the TRIZ and AHP’s factor to find out the difference of the best product process. 4.Compare the factor of TRIZ and AHP with the experiment’s difference. The final experiment result indicate that there are three factors of experiment combination AHP and TRIZ are totally identical, different factor compare with SN ratio and the mean have no significant effect, thus, we can know even if there are some difference between the factors that been selected by two different tools, it’s effeteness to the experiment is not significant. The results of the experiment-based research ,which displays that process capability (Cpk value) is obviously increased from 0.69 to 1.38 and 1.51, indeed improves the quality accuracy and shows that the combination of TRIZ/AHP and Taguchi Method' robust design is beneficial to the improvement of operation method and the quality upgrading.