提出了一種以空間三自由度并聯(lián)機(jī)構(gòu)作為主進(jìn)給機(jī)構(gòu)的并聯(lián)機(jī)床新結(jié)構(gòu)。建立了并聯(lián)機(jī)床主進(jìn)給機(jī)構(gòu)位置分析的輸入輸出方程，推導(dǎo)了奇異位形判別的解析表達(dá)式。該判別式在形式上為多項式代數(shù)方程，在推導(dǎo)過程中引入數(shù)值-符號處理技術(shù)，得到了多項式代數(shù)方程中每一系數(shù)元素的數(shù)值-符號形式的解析表達(dá)式。主進(jìn)給機(jī)構(gòu)的奇異位形的集合為參數(shù)空間的曲面片，得到了奇異曲面方程及奇異曲面的截面曲線圖，給出了奇異位形分析計算的數(shù)值實(shí)例。
關(guān) 鍵 詞 并聯(lián)機(jī)床; 虛擬軸機(jī)床; 奇異位形; 解析

Abstract A new type parallel machine tool, which utilizes a 3dof spatial parallel mechanism as main feed machanism, is proposed in this paper. The input-output equation of displacement analysis for the main feed mechanism of parallel machine tool is established. An analytical expression for determining singularity configuration which is a polynomial equation is set, and the numeric-symbolic manipulating technique is introduced in the paper. Analytical expressions of numeric-symbolic form for each coefficient of the ploynomial equation are derived. The section curve graph of a singularity surface is drawn. A numerical example of singularity configuration analysis is given for illustration.
Key words parallel machine tool; virtual axis machine tool; singularity configuration; close form solution