Re: Need speed switch for DIY funicular/hillside elevator

[nobody@xxxxxxxxxxxx (Dave Houston)]

In your initial post you said, "I am trying to figure out some kind of
simple safety mechanism in the event that the spools break loose from the
gearbox or shaft and start rotating freely". Now you indicate that's a minor
concern.

I'm confused. I thought it was "something major is wrong such as a
broken coupling or a broken shaft inside the gearbox" that was the primary
concern.

astutesolutions@xxxxxxxxxxxxx wrote:

>So here's what I'm thinking.  On the end of the spool, have a large
>sprocket that drives a chain to a smaller sprocket.  The smaller
>sprocket is hooked up to a go cart transmission (centrifugal clutch)
>that is underneath the drum units.  The gearing would mulitply the
>spin.  At high speed rotation, the clutch engages and the wheel turns
>and yanks the mousetrap and pulls out a jumper that opens the emergency
>stop button (motor shutoff).  Then it would take a manual reset to
>unlock, but if its spinning freely something major is wrong such as a
>broken coupling or a broken shaft inside the gearbox.


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