Experimental and numerical study of a plastic worm meshed with a steel helical gear

摘要

In this paper, the transmission mechanism of a plastic worm meshed with a steel helical gear is applied to achieve power transmission and motion transfer. Tooth profile equations of the gear pair are derived and general meshing conditions are proposed in terms of gear geometry. A mathematical model of the tooth profiles of the gear pair is established. Contact stress analysis and general evolution law of the tooth profiles are discussed using the finite element method. Material characteristics, mesh generation, contact definition, and constraint conditions are given. For comparison, analysis results of a steel worm meshed with a steel helical gear is also provided. Through the hobbing process, injection molding, and machining center, samples of steel helical gears, plastic worm, and steel worm are completed, respectively. A characteristic test of the transmission mechanism of the plastic worm meshed with a steel helical gear is carried out based on the microtransmission experimental platform. The contrasting results show that the plastic worm has better transmission performance.