Ω型双螺杆泵型线设计及啮合线分析

摘要 提出了Ω型双螺杆泵转子型线的设计原则,得到了Ω型螺杆转子原始型线方程,利用包络原理推导得出共轭型线方程及共轭型线与原始型线的啮合对应关系。用型线设计的双螺杆转子,啮合线封闭,接触线连续,能够形成密封的工作基元,因此新型线能够用于井下螺杆泵转子的造型设计。通过对转子啮合特性的分析,得到了齿形曲线方程式,对以后Ω型双螺杆泵的制作提供了一定的理论基础。

关键词：Ω型双螺杆泵、型线方程、啮合线、密封腔、三维模型

Abstract: For the existing screw type line equation，parametric modeling complex，long-time problems，according to the design principles and requirements of profiles，by using of coordinate transformation，Omega;-shaped symmetrical end face profile equations with easy-parametric modeling and good sealing，engagement properties were built． With respect to the pitch circle，rounded corners public t of the equations were deduced and defined ranges based on geometric relationships of screw driving; Visual Basic program language for the development tools，three-dimensional software SolidWorks for secondary development platform，achieved a parametric solid modeling of screw spiral sets; established the inherent characteristics of the screw analysis model，with ANSYS software did modal analysis of the bearing on screw under the constraints of rigidity and flexibility and considered the effects of different elastic stiffness of the natural frequency． The results show that: the natural frequency of the screw under elastic constraints is decreased obviously，the modes under two constraints are consistent，stiffness of the elastic element has no effect on the natural frequency of the elastic constraints． The research provided the theoretical basis for the improvement design of the double screw pump and the screw mode analysis，and greatly improved the design efficiency．

双螺杆泵主要是由杆、从杆、泵体、螺村补套、机械密封、密封座、轴承、同步齿轮等组成［1］，它依靠螺杆相互啮合时所引起的密封腔的容积变化来抽送液体。双螺杆泵中在工作中具有其他多螺杆泵所不具有的优点，如具有很高的吸入能力，能无脉动地连续供液且无搅拌、乳化现像。采用独立润滑的外置轴承可输送黏度范围宽广的各种介质，对输送介质不敏感等，其应用范围日益广泛。

双螺杆泵的关键部件是一对相互啮合的螺杆，螺杆螺旋面和其轴线的垂直面之间的截交线形成了型线，它的性能直接影响泵的效率、流量及使用寿命等，因此对双螺杆泵的型线进行研究有着很重要的理论意义和应用价值。国内现有对双螺杆的型线研究主要有:摆线对称型和渐开线对称型；非对称的有渐开线-渐开线、摆线-摆线和摆线-渐开线型［2］。摆线形型线螺杆的啮合性好方程简单，而渐开线可降低齿顶处工作运转时的冲击，又能保证型线与包络线的接触线的线啮合与连续性，泵的稳定性好,但方程复杂。

双螺杆泵主要是由同步齿轮、轴承、螺杆衬套、主动螺杆、从动螺杆、密

件及箱体和相关附件组成［3］。如图1所示，当主动螺杆转动的时候螺旋槽从左至右移动，主从动螺杆啮合把螺旋槽空间封闭(或有少量泄漏)，使螺旋槽中的介质(图中螺杆与衬套之间灰色部分)随着螺旋槽移动，最终从右端的出口输出。

1一同步齿轮；2一轴承；3一轴封；4一衬套；5一从动螺；6一主动螺杆