Gear rotation in planetary gear drive

[billbedore]

Inventor 2012

I'm not able to get the right gear rotation in a planetary gear drive that I'm working on. 

If I make the ring gear stationary and rotate the sun gear, the planetary gear engages and rotates around the  ring gear

but in the opposite direction of what it should be turning.  The planet to sun gear engagement rotates backwards regardless of what I do to the rotation constraint that I've applied. 

If I make the ring gear free to rotate, and the planet gear stationary, the gear train rotates properly.

I've attached a mock up of the plant gear system to share and show what I'm dealing with. 

Hopefully someone else has dealt with this problem and has a solution or work around.

Best regards,

Bill B.

[SKinzel]

I ran into a similar situation once when I was playing around with a roller bearing.  I couldn't ever get things to interact correctly so I gave up.  At the time it was mostly an excercise in understanding how constraints work together.  I'm guessing the answer to that question is "not quite right".

Sorry I don't have any answers but I also would be interested in the solution to this.

[JDMather]

When I ground any one of your parts Inventor shows errors in the assembly constraints.

I would create a planet carrier part to control the planets.

Looked like your assembly constraints could be simplified.
Work on it a bit more and post back.
I'll take a look once you have a carrier.

If you search here - I posted example here some years ago.

How many teeth on the ring gear?
What is the pitch circle diameter of the ring gear?

[JDMather]

Also - don't round off ratios and center-to-center distances.  Put in the actual number of teeth for the ratios.

and make sure you get the ratio correct order for input and output.