螺杆真空泵单头型线变双头方法研究

针对目前发展较为成熟的单头转子型线动不平衡问题,提出了一种将单头转子型线变为双头对称型线的方法。总结了该方法所适用的单头转子型线所需满足的条件,并用数学方法证明了所得到的双头型线能够正确啮合。定性分析计算了型线从单头变为双头后面积的变化,并以特定单头型线为例,计算了型线面积利用系数的变化。将特定单头型线变换得到对应的双头对称型线,用Solidworks三维软件建立转子模型并进行两个转子的装配,模拟验证了双头型线的正确性。该方法保留了原型线的接触线、泄漏三角形等特性,得到了具有较好动平衡性的双头型线。

Transformation of Single-Thread Profile into Twin-Thread Profile of Screw Vacuum Pump: A Simulation and Analytical Study

A novel twin-thread symmetrical profile was developed as a total solution to the dynamic unbalance problem of the single-thread rotor profile of screw vacuum pump.The necessary conditions,required on the transformation from single-thread profile into twin-thread profile,were summarized.The twin-thread profile was mathematically modeled,analytically calculated and numerically simulated by means of Solidworks software with a specific transformation example.The characteristics of both the single-thread and twin-thread profiles,including the correct meshing conditions,area utilization factor,contact-line and leakage triangle,were calculated.The results show that the newly-proposed twin-thread symmetrical profile outperforms the single-thread profile,not only because of the identical contact-line and leakage triangle,but also because of a much better dynamic balance.We suggest that the transformation scheme herein reported be of some technological interest in development of screw vacuum pump.