involute of circle meaning in English

圆的渐开线
圆的渐伸线

The advanced development on the new kinds of scroll profile has become the research focus in the profile design . used a new type scroll compressor of the combination profile in this paper , a scroll is constructed following this : the inner turn consists of the standard involute of circle , and the same to the outer turn . then the middle turn is one of arc
本文所研究的新型组合曲线涡旋压缩机最内圈以基圆渐开线构成,中间段以圆弧过渡,最外圈由圆渐开线构成,能发挥不同型线的优势,是一种能满足多性能较优要求、形状性态良好的涡旋型线,与传统的基圆渐开线构成的涡旋压缩机相比,具有效率高、泄露量少、体积利用系数大等优点。