- tsp
Last update 12 Jun 2026
2 mins
Simple planetary gear set
Enter any two gear sizes. The calculator completes the geometry, evaluates the selected configuration, and draws the gear set.
01
Enter any two tooth counts. Pitch diameters use d = m · Z.
02
The input and output must be different members.
03
Complete the geometry to calculate the ratio.
Willis equation: (ωs − ωc) / (ωr − ωc) = −Zr / Zs
04
Schematic pitch geometry. Tooth shapes are illustrative, not manufacturing profiles.
This article is tagged:
Dipl.-Ing. Thomas Spielauer, Wien (webcomplainsQu98equt9ewh@tspi.at)
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