@Ulrich_Baer In this case, because there are so few of these possible positions, none of them overlap. For more typical gearsets with larger numbers of teeth, there will be more possible positions for gears than there is space to actually fit them.
Btw, the number of teeth on the planets doesn’t seem to matter. The number of teeth in the ring gear is always equal to the number in the sun gear plus twice the number in each planet. This means that the number in the ring and the number in the sun are either both odd or both even. If you could have an even number in one and an odd number in the other, the number of planet positions would be half the sum of the ring and sun teeth, but since the planets must have a whole number of teeth and the difference is equal to twice that number, that situation can never happen.
as this is a cycloidal gear we don’t have teeth as there is always a 1:1 match of the coresponding surfaces.
“Teeth” is the number of repetitions of the pattern of curves along the surface. This gearset has 2 “teeth” on the sun, 1 “tooth” on each planet, and 4 “teeth” on the ring.
Yes you are right, but there is no need to have them - as there is in a normal gear to keep synchronicity. I am not arguing against you, but a normal gear with only 1 teeth planets can’t work. These Planets rotate out of their center which probably allow them to fit more in as the planet ring is probably not steady.
Slightly related: check out https://m.youtube.com/channel/UCERyl8JwFJuCISJfcnpCvwA
You may know about him already.
He was at MRRF, great guy. No one is geeking out on gears like this guy 
one cool learning for me: gear plugin for fusion 360. Neat stuff.
What, after 19 comments, no one has said, “daaaaawh, look he made ‘hearts’ (for his sweetie).”
Heartless bastards!
