The Influence of Kinematics Variation on Multispeed Gears Meshing

Abstract

Multispeed gears are noncircular gears whose kinematics varies during a rotational period, alternating uniform and variable motions. Due to the limited information on multispeed gears design and performance, the paper presents i) the generation of multispeed gears, using the design hypothesis of the transmission ratio variation and ii) investigations on meshing conditions, as a qualitative information on gears contact. To generate multispeed gears, the gears transmission ratio are defined by hybrid multiple parameters functions with parabolic and trigonometric variations. Virtual models of the multispeed gears, produced by the Matlab-PHP-MySQL-AutoCAD interference, are further used for the gear meshing analysis, the theoretical static contact evolution and distribution along the teeth being investigated and compared for both kinematics. It was found that the trigonometric variation of the gears transmission ratio improves the gears meshing in gear concave zones, while the parabolic variation has benefits on tooth contact pattern in zones where the gears centrodes geometry is changed from circular to noncircular shapes.