flank clearance meaning in English

侧向间隙
螺腹间隙

This paper develops a mathematical model for the solution to the longitudinal tooth curve of an internal gear shaver based on the simplified principle for space transmission of a helical gear pair without flank clearance , and proposes a calculating approach of the profile modification of the grinding wheel to be used for grinding the longitudinal tooth curve of the shaver
摘要用简化的空间螺旋齿轮作无侧隙啮合传动的原理，建立了求解内剃齿刀齿向曲线的数学模型，并给出了修磨这种齿向曲线的盘形砂轮的廓形计算方法。