螺杆真空泵双头对称等螺距转子型线研究

Novel Rotor Profile of Symmetric Twin-Thread Screw with Fixed Pitch for Screw Vacuum Pump

结合现有特殊爪型转子型线与单头螺杆转子型线特征,提出了一种双头对称爪型等螺距螺杆真空泵转子型线。通过理论推导得到了该型线完整的端面方程,导出了该型线的面积利用系数和抽速的公式,列出了这种型线的特点。使用Solidworks三维软件绘制出了这种转子的三维实体模型,模拟拟合验证了端面型线的正确性。分析得到螺杆转子端面型线关于中心对称且两转子完全相同,与特殊爪型转子型线相比易加工、节省工时,与单头螺杆转子相比具有较好的动平衡性,可为国内外从事真空泵设计和研发人员提供参考。

A novel type of rotor profile of symmetric twin-thread screw with fixed pitch was proposed for the screw vacuum pump by combining the profiles of the conventional single-thread screw rotor and special claw-typescrew rotor. The end-face profile of the proposed rotor was mathematically modeled,analytically calculated,and numerically simulated with software package,Solidworks. The equations were derived to describe the end-face profile; the area utilization coefficient and pumping speed were calculated,the 3-dimensional model of the rotor was plotted with software package Solidworks,and its characteristics were discussed. The simulated results agree very well with those calculated by solving the equations of the end-face profile. The simulated and calculated results show that the screw rotor profile is centro-symmetric,and the two rotors are identical. The proposed twin-thread screw rotor outperforms the special claw-type rotor and single-thread screw rotor simply because of an easier fabrication and better dynamic balance.