With this geometry node group you can generate cogs.
It will use a collection to implement an inner mesh to you liking and switch between them.
The speed and teeth adjust automatically to fit the previous cogs that where created to create chains of cogs easilly.

Parametrs that can be adjusted:
Radius
Depth
Speed
Teeth Amount
Teeth Length
Inner Instance
Teeth Offset
Teeth Width Inside
Teeth Width Outside