Rotational Transmission Error of K-H-V-Type Planetary Gears With Cycloid Gear : 3rd Report, Mutual Effects of Errors of the Elements on the Rotational Transmission Error

Abstract

The rotational transmission error of K-H-V-type planetary gears with cycloid gears should be as small as possible in order to apply these planetary gears to the industrial robot and a machine requiring precise positioning. In this paper, after the K-H-V-type planetary gears with cycloid gears were transformed into a two-dimensional model with twenty degrees of freedom, both the mutual effects of errors of elements and the effect of plural cycloid gears on the rotational transmission error were determined theoretically, and moreover the theoretical results were checked experimentally in some cases, with the following conclusions. (1) The rotational transmission error cannot be determined by superposition of each rotational transmission error produced by individual error. (2) The tooth profile error where the tip has a convex error of cycloid gear should be avoided to decrease the rotational transmission error. (3) The rotational transmission error whose frequency coincides with the carrier rotational frequency is produced by errors of cycloid gears or carrier and assembly error or accumulative pitch error of internal gear. (4) The rotational transmission error increases when the backlash increases. (5) Plural cycloid gears have a beneficial effect on decreasing the rotational transmission error.