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## Main Question or Discussion Point

I am trying to solve gear ratios for a differential gearset when one of the output shaft's rotation is limited...

Let's say:

I have a power split device with an input (A), output1 (B) and output2 (C).

C has a speed limiting mechanism attached to it.

Without limiting the speed of C, ratio A:B is 2:1 and ratio A:C is 2:1.

Let's apply a 300 RPM input to A without the speed limiting device engaged.

B will be spinning at 150 RPM.

C will be spinning at 150 RPM.

Engage the speed limiter and slow C down to 75 RPM.

How do I find the speed of B?

My guess is C(before limiter) - C(after limiter) + B(before limiter)

150-75+150 = 225

So, the functional output gear ratio A:B after limiting C to 150 RPM would be 300/225 or 1.3333:1

I think this is right so far.

Please correct me if I am wrong.

If that is right, what happens if A:B does NOT equal A:C?

If A:B = 3:1 and A:C = 2:1...

If we apply the same 300 RPM input(without the limiter) we will have:

B = 100 RPM

C = 150 RPM

If we slow C down to 75 RPM again how do we solve for B?

If we apply C(before limiter) - C(after limiter) + B(before limiter) we get:

150 - 75 + 100 = 175 RPM @ B

Therefore A:B after the limiter is engaged is 1.714:1

Is this right?

It feels like there is missing something.

Thanks for any help you can give.

Let's say:

I have a power split device with an input (A), output1 (B) and output2 (C).

C has a speed limiting mechanism attached to it.

Without limiting the speed of C, ratio A:B is 2:1 and ratio A:C is 2:1.

Let's apply a 300 RPM input to A without the speed limiting device engaged.

B will be spinning at 150 RPM.

C will be spinning at 150 RPM.

Engage the speed limiter and slow C down to 75 RPM.

How do I find the speed of B?

My guess is C(before limiter) - C(after limiter) + B(before limiter)

150-75+150 = 225

So, the functional output gear ratio A:B after limiting C to 150 RPM would be 300/225 or 1.3333:1

I think this is right so far.

Please correct me if I am wrong.

If that is right, what happens if A:B does NOT equal A:C?

If A:B = 3:1 and A:C = 2:1...

If we apply the same 300 RPM input(without the limiter) we will have:

B = 100 RPM

C = 150 RPM

If we slow C down to 75 RPM again how do we solve for B?

If we apply C(before limiter) - C(after limiter) + B(before limiter) we get:

150 - 75 + 100 = 175 RPM @ B

Therefore A:B after the limiter is engaged is 1.714:1

Is this right?

It feels like there is missing something.

Thanks for any help you can give.