gearwheel encodjng

[Ross Forgione]

I actually meant the etire assembly was enlosed - Encoder hblock and
all. The slotted encoder disk has a shaft which protrudes through the
case. In the printer application, a collet is used to attach it to the
carrige drive motor shaft. Collet ID is around 10mm. 

Sorry for not being real clear in my original post.

> 
> In a message dated 97-02-04 22:45:06 EST, you write:
> 
> > Ah one important thing to mention, is that these units are sealed quite
> >  well so dirt, grease etc should not present a big problem.
> 
> They are sealed, however road crud can get between the IR transmitter and the
> IR receiver, thus blocking view.  Magnetics is probably the best way to go,
> and the circuitry to drive it would be similar...
> 
> Fred
>