VDI 2157:2012-10 (R2016)

Planetary gears are used in many cases of drive engineering. Their advantages are coaxial input and output shafts, a round and compact design, the possibility of extremely high or low speed ratio with one or a few planetary gears, the possibility of superposition of speeds and torques as well as the possibility of switchable gear structures. The simple planetary gears and the compounded planetary gears are based on the same mechanical laws. Therefore they can be calculated with the same equations on an analysis or a synthesis. The new edition actualizes the version of September 1978. The systematic has been basically reworked and inertias, accelerations as well as shifting elements have been integrated. With it the new technical and mathematical possibilities to calculate planetary gears, particularly linear systems of equations, have been regarded. The new edition is the basis of a computer aided systematically description and analysis of planetary gears. Actual examples show gearboxes with high speed ratios and gearboxes for automotive applications.