How about electric car window motors? or check out a catalog such as
W.W.Grainger that has reversible motors. Or maybe the guts of a
reversible drill motor. You might use an electric clock timer with a
cam switch that could be set to 60 seconds or less to close a
normally-open contact (or vice versa) when the hand or wheel comes
around. The visitor would activate a start button to initiate the "up"
motorswitch; when the desired time has elapsed, the timer would drag
across the "down" switch. Hmmm...have to work out all the bugs...

I'm sure there's a way to do this electronically instead of
mechanically, something from Radio Shack probably.

Just some free-association here; half-formed product of too little
knowledge...Hope I haven't confused anybody more than I am!

:  )