Gear reduction question

[Andy Baker]

If two dissimilar gears are mounted on the same shaft, then there is no reduction.

However, using this setup coupled with other gears is a good way to produce a reduction.

Here is an example:

A Fisher-Price motor has a 19 tooth gear.

This 19 tooth gear is mated with a 57 tooth gear, providing a 3:1 reduction translated to the shaft which the 57 tooth gear is mounted.

On that same shaft which the 57 tooth gear is mounted, there is another 19 tooth gear, attached to the same shaft.

Now, this second 19 tooth gear is meshed with a 4th gear, a 38 tooth gear, which provides an additional 2:1 reduction.

The total reduction of this system is a 6:1 speed reduction, done in a very small package.

Andy B.