RE: Engineering 101

["Mullen, Tim \(IIS\)" <Tim.Mullen@ngc.com>]

Trevor Boicey

> You might also be thinking of hypoid gears, which 
> are essentially the same as bevel gears but don't 
> share a common axis...
>
> Hypoid gears are usually smoother, since there is 
> continuous gear contact. ...

They also make spiral cut bevel gears to remove the gear back lash and
provide continuous gear contact.  They reference them in the bevel gear
section in the McMaster catalog <http://www.mcmaster.com/>.

One problem with the continuous gear contact is that the forces are
actually a sliding contact - these requires high stress lubricants and
takes a bit more power, but the smoothness and quietness is worth it...

Tim Mullen