Abstract

Curvilinear cylindrical gear drives are a type of parallel-axis gear set, and the longitudinal geometrical shape of the gear teeth is a part of the circular arc. This study aims to develop a curvilinear cylindrical gear drive with superior transmission performance. This study proposes a curvilinear cylindrical gear drive with a parabolic profile. The gear tooth surfaces are generated by a face-milling cutter with a straight-line profile, and the matching gear tooth surfaces are generated by a face-milling cutter with the parabolic profile. Initially, mathematical models of the gear set are described based on the theory of gearing. The finite element method and tooth contact analysis algorithms were applied to contact and bending stress analyses. Finally, four numerical examples are provided to illustrate the transmission performance of the curvilinear cylindrical gear drive with the parabolic profile. The study results show that curvilinear cylindrical gear drives have superior transmission performance compared to those with a straight-line profile.

Abstract

The fixed-setting face-milled curvilinear cylindrical gear (FSC gear) is a type of parallel-axis gear characterized by a circular arc-shape tooth in the longitudinal direction, with contact impressions on the tooth surface that can be adjusted through the manufacturing process. The finite element method is employed to investigate the effects of various gear parameters on the load-sharing factor (LSF) of FSC-gears. Initially, a sensitivity analysis was conducted to enhance the accuracy of the finite element model for FSC gear drives. Secondly, the accuracy of the finite element model was validated by the Hertzian contact theory. Furthermore, the correctness of the finite element method for determining the LSF was validated based on American Gear Manufacturers Association standards (AGMA). In this study, the effects of assembly errors, tooth modification, driving torque, cutter radius, and contact pattern size on LSF are investigated by numerical examples. The results show that the precise LSF can be determined without intentionally increasing the element density of the subsurface of the tooth surface. Compared with the AGMA standard, the finite element method offers advantages in calculating the LSF of any non-standard gear. The influence of the milling cutter radius and the tooth surface contact pattern size on the LSF can be neglected.OPEN ACCESS Received: 11/08/2024 Accepted: 21/11/2024 Published: 07/04/2025

Abstract

The fixed-setting face-milled curvilinear cylindrical gear (FSC gear) is a type of parallel-axis gear characterized by a circular arc-shape tooth in the longitudinal direction, with contact impressions on the tooth surface that can be adjusted through the manufacturing process. The finite element method is employed to investigate the effects of various gear parameters on the load-sharing factor (LSF) of FSC-gears. Initially, a sensitivity analysis was conducted to enhance the accuracy of the finite element model for FSC gear drives. Secondly, the accuracy of the finite element model was validated by the Hertzian contact theory. Furthermore, the correctness of the finite element method for determining the LSF was validated based on American Gear Manufacturers Association standards (AGMA). In this study, the effects of assembly errors, tooth modification, driving torque, cutter radius, and contact pattern size on LSF are investigated by numerical examples. The results show that the precise LSF can be determined without intentionally increasing the element density of the subsurface of the tooth surface. Compared with the AGMA standard, the finite element method offers advantages in calculating the LSF of any non-standard gear. The influence of the milling cutter radius and the tooth surface contact pattern size on the LSF can be neglected.OPEN ACCESS Received: 11/08/2024 Accepted: 21/11/2024 Published: 07/04/2025