干式螺杆真空泵转子成型加工及其刃形计算  

Rotor Form Machining and its Form Cutter Calculation for Dry Screw Vacuum Pumps

作　　者：李丹童 何志龙[1] 邢子文[1] LI Dantong;HE Zhilong;XING Ziwen(School of Energy and Power Engineering,Xi'an Jiaotong University,Xi'an 710049,China)

机构地区：[1]西安交通大学能源与动力工程学院,西安710049

出　　处：《真空科学与技术学报》2022年第2期110-117,共8页Chinese Journal of Vacuum Science and Technology

摘　　要：干式螺杆真空泵转子的快速、高精度加工是提升整机性能与降低生产成本的关键技术。本文基于一种附加刀具垂直位置与倾角调节的螺杆转子成型机床结构,采用接触线法建立其刀具刃形求解的数学模型,分析转子初始转角、刃形求解范围参数、刀具中心距、斜角与倾角对刃形的影响规律。结果表明:过大的刀具斜角会导致刃形的凹面结构,而过小的斜角使得刃形发生干涉。过大的刀具倾角同样使刃形出现凹面结构,而刀具倾角过小时,刃形求解过程中出现无解现象。此外,随着求解范围参数、转子初始转角与刀具中心距的增加,刀具半径得以有效提升,但过高的刀具中心距将导致无法获取有效刃形。在刀具位置参数设计过程中,应选取适中的刀具斜角、倾角与中心距,避免刃形出现干涉、凹面与无解现象,为提高刀具半径,可适当提高求解范围参数。该方法可有效应用于等螺距或阶梯式变螺距螺杆真空泵转子成型加工及其刃形计算。The rapid and high-precision machining of rotors is the key technology to improve the performance and reduce the production cost for dry screw vacuum pumps. In this study, the mathematical model for the form cutter profile generation is proposed employing the contact line method, which is based on a novel forming machine with the adjustable vertical position and tilt angle of cutters. We analyze the influence of the position parameters(initial rotation angle, solution range parameter, center distance, oblique angle, and tilt angle) on the cutter profile.Results show that an overlarge oblique angle leads to the concave phenomenon, and a too narrow oblique angle results in interference in cutter profiles. An overlarge tilt angle also gives rise to the concave phenomenon, while a too-small tilt angle causes the unfeasible solution of cutter profiles. Additionally, with the increase of the solution range parameter, center distance, and initial angle, the cutter radius effectively increases while an overlarge center distance results in the unfeasible cutter profile. During the design of form cutter position parameters, oblique angle,tilt angle, and center distance should be selected carefully to avoid interference, concave, and unfeasible solution phenomenon for cutter profiles. To improve the cutter radius, the solution range parameter could be reasonably increased. The proposed method could be effectively applied to calculate the form cutter profile for the fixed-pitch or stepped variable-pitch screw vacuum pumps.

关 键 词：螺杆真空泵 转子加工 成型刀 刃形计算 

分 类 号：TB752[一般工业技术—真空技术]