A method for point-contact conjugate tooth surfaces with a constant instantaneous transmission ratio generated by point-contact conjugate involute helicoids. (July 2023)

• Record Type: Journal Article
• Authors: Ren, Wen; Li, Haitao; Zhang, Shengli; Li, Miaomiao; Li, Jie; Wang, Tianyu; Ma, Ming
• Is Part Of: Mechanism and machine theory. Volume 185(2023)
• Publication Date: 2023-07
• Subjects: Point-contact conjugate -- Constant instantaneous transmission ratio -- Involute helicoid -- Two degrees of freedom -- Two generating surfaces; Machine theory -- Periodicals; Machinery -- Periodicals; Machines -- Périodiques; Génie mécanique -- Périodiques; Machine theory; Machinery; Periodicals; 621.81
• DOI: 10.1016/j.mechmachtheory.2023.105324
• Languages: English
• ISSNs: 0094-114X

Abstract

Highlights: A method for generating point-contact conjugate tooth surfaces is proposed. The mechanism of point-contact conjugate tooth surfaces is revealed. A simplified method of calculating contact points is given. Two novel types of point-contact conjugate worm drives are proposed. The proposed method is verified by numerical simulations and meshing tests. Abstract: Point-contact conjugate tooth surfaces are insensitive to manufacturing errors and assembly errors and have no transmission errors. However, design conditions for the current method of generating point-contact conjugate tooth surfaces are strict or lacking. This study proposed a method for point-contact conjugate tooth surfaces with a constant instantaneous transmission ratio generated by point-contact conjugate involute helicoids. According to relative motions of single- and two-degree-of-freedom in generating, design criteria were given and a mathematical model of the method was established. The mechanism of point-contact conjugate tooth surfaces was obtained by investigating the relationship between the engagement lines/surfaces, and kinematics was studied, in which the mechanism with a constant instantaneous transmission ratio was geometrically analysed. Based on this method, four types of point-contact conjugate worm drives were studied, in which two novel types of worm drives were developed, i.e., a point-contact conjugate toroidal involute (TI) worm drive, and a point-contact conjugate involute cylindrical (ZI) worm drive. The method was validated for correctness using numerical simulations and meshing tests and the influence of adjustable parameters on the meshing performance was outlined.