Gears in Inventor

[petek]

Originally Posted by sanddrag

You can make one tooth profile and then revolve it around in the sketch. Real gears have an involute curve on the tooth, but you can approximate it with an average radius. However, your best bet is getting ones someone else made, even though they probably don't have involute curves either. It's hard to make a drawing good enough to cut gears from (because of the involute) but the constant radius should be just fine for an inventor model.

There is a model of an involute spur gear on cbliss.com:
http://www.cbliss.com/inventor/Parts...olute Gear.zip

The creation of the involute curve is done via an embedded Excel spreadsheet, which by itself is worth looking at to see how it works.

Be aware that this generates a pretty massive file, especially for large #'s of teeth. Cybersonics used this model for the basis of some gears we used in our machine last season, but created toothless "dummies" for general CAD modelling and substituted the involute ones only where appearance made it worth the overhead.