Re: [CAD_CAM_EDM_DRO] Re: Sherline Problem
Posted by
Michael Fagan
on 2007-11-09 16:14:01 UTC
I am rather fond of the Allegro series chips--they are designed for
automobile ABS systems, so they're quite rugged, have minimal requirements,
and aren't sensitive to environmental conditions such as ambient light which
affect optical sensors. Gears work well--on my last application, I just
found a surplus gear that worked and stuck it on the end of the shaft. In
my experience, a constant stream of pulses (like a gear or sprocket) seems
to work better than a single pulse per revolution, unless your RPM's are
very high.
automobile ABS systems, so they're quite rugged, have minimal requirements,
and aren't sensitive to environmental conditions such as ambient light which
affect optical sensors. Gears work well--on my last application, I just
found a surplus gear that worked and stuck it on the end of the shaft. In
my experience, a constant stream of pulses (like a gear or sprocket) seems
to work better than a single pulse per revolution, unless your RPM's are
very high.
On Nov 8, 2007 8:58 PM, David G. LeVine <dlevine@...> wrote:
> At 01:03 PM 11/8/2007, you wrote:
> >You only need one pulse for threading. This is well established.
> >I recommend putting another type of phototransistor on the spindle, a
> >reflective one.
> >Then paint one small reflective stripe on the spindle.
>
> Another sensor is the Allegro ATS series (see
> http://tinyurl.com/229gtv ) which are under $5.00 and can be 2.5 mm
> away. Simply put a screw into the pulley and sense it! Of course if
> you have a gear available, you get as many pulses as teeth.
>
> David G. LeVine
> Nashua, NH 03060
>
> [Non-text portions of this message have been removed]
>
>
>
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