Re: Brake method needed for hillside lift

["Gemini" <spamthis@ nowhere.net>]

The simplest way would be to wrap and connect the cable to (a spring
loaded?) spool under the carriage that would allow a lever to drop down on
some type of stops affixed to the tracks so that if the cable ever became
slack it would drop down and engage on one of the stops.
I remember this method being used on larger garage doors as a safety in case
the counterbalance failed.
Let me know if this makes no sense verbally and I'll sketch it out for
you....


<astutesolutions@xxxxxxxxxxxxx> wrote in message
news:1162064778.678313.85220@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> (this is a repost from comp.home.automation).  Thanks.
>
> My dad and I built a homemade hill lift (in Europe refered to as
> funiculars) in Eastern Tennessee.  You can see a working demonstration
> and picture of it at:
>
> http://www.funimag.com/photoblog/index.php/20061026/a-do-it-yourself-...
>
>
> The tram works fine, but 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.  Since my wife and kids
> ride this thing, I'd like some kind of backup solution in the event of
> major catastrophe.  We are using 2 cables instead of one even though
> one can handle 5 times the max load, and we have a braking motor to
> stop, but both of those would be moot if the spool spins out of
> control.
>
> I am thinking of having some way of measuring the outfeed speed of the
> cable (or spool) and have some emergency brake apply if a limit is
> exceeded.
>
> Any suggestions?  I thought about putting fan blades at end shaft of
> the spool to have air slow it down, but that would be a little
> unsightly.  I'm looking for a simple solution, one preferably without a
>
> computer since this is outdoors and needs to be functional 100% of the
> time.
>
> Thanks in advance.
> Jeff
>