汽车单叶片真空泵设计中的最优椭圆曲线

Optimal Elliptic Curve in Single-vane Vacuum Pump Design of Automobiles

单叶片真空泵的设计主要是确定泵体内腔曲面,使同时作旋转运动和径向滑动的叶片的圆柱形端面和它保持相切。泵体内腔曲面的投影必须是一条封闭的光滑曲线。设计时,这条光滑曲线的一部分通常被提前选定,而剩余部分则根据几何约束产生。尽管一般的椭圆曲线可以满足参考曲线和生成曲线在连接点一阶可导,但在连接点通常是二阶不连续的。将找出一条最优的椭圆参考曲线,使得泵腔形线在连接点处不仅是一阶连续的而且是二阶连续的。这将使得泵的运转更加平稳并减小由于叶片径向加速度不连续产生的振动和噪声。

T he design of single-vane vacuum pump is to determine the cavity surface of pump so as to make the vane＆#39;s cylindrical end face in tangency with the vane .The projection of the cavity surface should be a closed smooth curve .In design ,one part of the smooth curve is usually selected in advance ,and the rest part is generated in the light of geometric constraint .The reference[1] points out ：elliptic curve can be used as the design reference curve .Although ordinary elliptic curves can guide reference curve and pro-duced curve at the connection point of the first stage ,but they are not continuous at the second stage .This will make the operation of pump more stable ,and reduce the vibration and noise caused by discontinuous radial acceleration of vane .