分度盤之可靠度分析與精度壽命計算

近幾年國內外醫療與航太產業的蓬勃發展，五軸加工零件的需求變多，國內整機製造商多朝向五軸加工設備發展，在第四、五軸的分度盤要求亟需，除了精度要求高之外，亦要求可靠度與穩定性要好。國內的四、五軸產品多被拿來跟日本NEKKEN、TSUDAKOMA比較，其可靠度與精度壽命也被要求一樣，但是售價卻是為一半。因此本文將要針對四、五軸分度盤的產品，進行失效模式及失效率進行探討，讓國內模組廠知道如何提升產品之可靠度，並且進行蝸輪蝸桿的背隙與磨耗之研究。研究中透過接觸赫茲應力的理論計算，來得到背隙的生成與精度壽命彼此的關聯性，這些研究成果將可剖析國內產品目前的問題，爾後經由改善將可以提升產品可靠度與精度壽命，擺脫低價競爭的市場。

關鍵字

可靠度；赫茲應力；接觸磨耗

並列摘要

The needs of 5-axis machining parts have been increased since the development of medical and aerospace industries. As a result, the tendency leads to the domestic manufacturers to jump into the 5-axis machinery field. The requirements of 4 or 5-axis rotary table have been raised not only about the accuracy but the reliability and the stability as well. Taiwanese rotary module products are often compared with Japanese products, such as these from NIKKEN and TSUDAKOMA. Meanwhile, Taiwanese products are asked for the same quality and accuracy life as the Japanese counterparts but with a half of the cost. Therefore, the failure modes and the failure rate of the multi-axis rotary table were discussed, and a reference method was offered to manufacturers to improve the reliability of their products. The study of the backlash and the wear of a pair of worm and worm gears was included in this article. The relation between the increments of backlash and the accuracy life was defined through Hertz contact theory. Hopefully the results can be used to improve the reliability and the accuracy life of the products and to get out of the rival price competition.