Re: Need speed switch for DIY funicular/hillside elevator

[astutesolutions@xxxxxxxxxxxxx]

Dave Houston wrote:
> Look here also for other general ideas...
>
>      http://en.wikipedia.org/wiki/Dynamometer
>
> One possibility would be a small air compressor that would be driven by the
> spool shaft with a discharge to the atmosphere through a fixed orifice. At
> slow speed there would be little resistance but as the speed increases the
> resistance increases, slowing the spool. You want to be sure that everything
> is sized to be safe - you don't want the compressor or any associated pipes
> to burst. You might even let the discharge drive a whistle to warm anyone
> nearby.

Yes, something like that could work.

 At the end of the drums is part of the 1.25" diamater shaft that
sticks out.  I could increase the torque on it by using 2 different
gears (large one on shaft, smaller on compressor) connected with a
chain to increase the rotational speed.

When going downhill, even if it was in resistance mode, the motor would
overpower the slowdown, but in a freespool situation it could slow it
down as desired.

It would be nice if it was able to only apply torque in one direction
like a bicycle wheel.  I wouldn't want it to torque on the trip up, but
just on the trip down.  I suppose I could use a bicycle setup for
exactly that purpose, but I think my dad would scoff at the
non-industrial sizing of it, lol.