How Do You Solve a Complex Epicyclic Gearbox Assignment?

[dstealth]

Hi all, I'm Chris, a first time poster!

Currently stuck on an assignment question for my mechanical engineering course. The question is shown in the picture below. The capital T refers to 'teeth', as in 20T is 20 teeth on that particular gear. Ignore the little arrows with P and S - that is just me labeeling up the planetary and the sun gears. I answered a previous question on epicyclic gearboxes no problem but we have not been taught how to answer one this complex:-

Any pointers?

Thanks in advance.

 

[rock.freak667]

The question is essentially asking for the ratio of the output speed to the input speed.

If I remember correctly the module m= D/T and for meshing gears, the modules are the same.

 

[dstealth]

The question is essentially asking for the ratio of the output speed to the input speed.

If I remember correctly the module m= D/T and for meshing gears, the modules are the same.

Shown in the pictures is the previous question which that question is based upon, along with my working out. I calculated a 6:1 reeduction ratio for the first question and a fixing torque of 25.46 Nm. I just don't know how to do the second question of the 'modified' gearbox that I posted in the first post.

Thanks

 

[dstealth]

I'm sure the working out is simple, it's just we haven't covered any examples like this in the lesson.