Mesh theory of angle modified dual tori double-enveloping toroidal worm drive  

作　　者：ZHAO YaPing1, SU DaiZhong2, ZHANG Zhao1, WEI WenJun3 & DONG XueZhu3 1 College of Machinery and Automation, Wuhan University of Science and Technology, Wuhan 430081, China 2 Advanced Design and Manufacturing Engineering Center, Nottingham Trent University, Nottingham NG1 4BU, UK 3 College of Engineering, China Agricultural University, Beijing 100083, China 

出　　处：《Science China(Technological Sciences)》2010年第7期1913-1927,共15页中国科学（技术科学英文版）

基　　金：The research work in this paper was fully supported by National Natural Science Foundation of China (Grant Nos. 50705068, 50810105045);China Hubei Provincial Natural Science Foundation (Grant No. 2007ABA282);the Key Program of the Science Research Foundation of Wuhan University of Science and Technology (Grant No. 2006XZ6)

摘　　要：In this paper, the meshing theory of the angle modified hourglass worm drive is enriched and developed. The ordinary condition of the angle modification is derived and the physical significance of the modification is interpreted. A normal section methodology is proposed for meshing analysis, which can be used to compute the normal distance near a singular meshing point of a conjugate surface couple. By means of the method and after analyzing the normal transversals, it is specified that the worm helicoid, the nominal former contact zone and the new contact zone intersect each other along the locus of singular points of the instantaneous contact lines of an angle-modified worm pair. As a result, it is explained clearly that those three osculate each other but the osculations are different in degree. Moreover, the mechanism of removing the twice-contacted zone from the worm gear tooth surface is clarified and the reason of shortening the worm working length is also elucidated. With the help of the theory described in the present paper and the thorough and systematic research on the relevant meshing characteristics, the angle modified dual tori double-enveloping toroidal worm drive has been shown to be an excellent new-fashioned hourglass worm set.In this paper, the meshing theory of the angle modified hourglass worm drive is enriched and developed. The ordinary condition of the angle modification is derived and the physical significance of the modification is interpreted. A normal section methodology is proposed for meshing analysis, which can be used to compute the normal distance near a singular meshing point of a conjugate surface couple. By means of the method and after analyzing the normal transversals, it is specified that the worm helicoid, the nominal former contact zone and the new contact zone intersect each other along the locus of singular points of the instantaneous contact lines of an angle-modified worm pair. As a result, it is explained clearly that those three osculate each other but the osculations are different in degree. Moreover, the mechanism of removing the twice-contacted zone from the worm gear tooth surface is clarified and the reason of shortening the worm working length is also elucidated. With the help of the theory described in the present paper and the thorough and systematic research on the relevant meshing characteristics, the angle modified dual tori double-enveloping toroidal worm drive has been shown to be an excellent new-fashioned hourglass worm set.

关 键 词：HOURGLASS WORM ANGLE modification double-enveloping osculation normal TRANSVERSAL 

分 类 号：TH132.44[机械工程—机械制造及自动化]