Comparison of Selected Parameters of a Planetary Gearbox with Involute and Convex–Concave Teeth Flank Profiles

Abstract

This article presents a model of the geometry of teeth profiles based on the path of contact definition. The basic principles of the involute and convex−concave teeth profile generation are described. Due to the more difficult manufacturing of the convex−concave gear profile in comparison to the involute one, an application example was defined that suppressed this disadvantage, namely a planetary gearbox with plastic-injection-molded gears commonly used in vehicle back-view mirror positioners. The contact pressures and the slide ratios of the sun, planet, and ring gears with both teeth profile variants were observed and the differences between the calculated parameters are discussed.

Keywords

• planetary gear
• convex–concave tooth flank
• contact pressure
• specific sliding