Re: Need speed switch for DIY funicular/hillside elevator

[astutesolutions@xxxxxxxxxxxxx]

> "Robert L Bass"  wrote ...
>  > A centrifugal brake should do the job.  Ideally, the brake engages as the
> drum starts spinning fast. As the brake slows the drum, it
> > eases up a bit, allowing a safe descent.  ISTR they used something like
> > this on the tram at a ski lodge in NH.
>
> You might be able to do this inexpensively by using centrifugal clutch from
> a go cart.  Instead of connecting between the drive and driven system, you
> could connect it to the cable (requires a good grip between the pulley and
> the cable) and a resistance element.  As the clutch spins, it locks up and
> the resistance element comes into effect.
> The advantage of this would be that the car would never come to a stop and
> would return people to the bottom of the hill.
> The disadvantage is that it could be difficult to adjust this system to
> limit the speed so that the car is moving slow enough when it gets to the
> bottom.
>
> ---
>
> Based on this being rarely used safety device.  I like the idea of simple,
> even if it requires that people get off part way up the hill.
>
> Bill Fuhrmann
>

Yes, something like this might work.  The spring/lock cable grap could
be held in the open mode almost like a mousetrap with a little force
that is easily triggered provided it could be done so that no jostling
or sharp inpact would force it to snap.

Another thought along a similar lines is to have two brake pads pushing
on the cable with a spring applying the force (like an emergency brake
on car?).  A fulcrum weight could hold the tension off of the spring
keeping open and something like that centrifugal governor could lift up
on the weight at higher speeds.  Cool.  Thanks!