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Archimedes Screw Escalator

hanging by a thread
  (+2, -1)
(+2, -1)
  [vote for,

Imagine in the middle of a shopping center or lobby seeing a giant revolving pyramid whisking people up and down between floors. The threaded cone would resemble the magnified tip of a wood screw with two threads.

One thread would be for riders going up and one for those going down. Each person would stand on a wheeled platform like a skateboard going sideways, with an encircling handrail. The platforms are connected to the inside of the screw through a continuous slot along the vertical side of each thread.

Those going up would enter at one point along the base and step onto platforms to be moved upwards and inwards while still facing in the same direction. These platforms are held in the same orientation through the slot as the screw presses them upwards. On the floor above, opposite the up exit, those going down step onto platforms that are control-braked through the slot to let them glide down the moving incline between escalating queues of riders above and below them.

FarmerJohn, May 02 2004

Double Helix Escalators http://www.halfbake...0Helix_20Escalators
Mickey the Fish's idea is more two (up and down) conventional escalators twisted in a helix. Mine is more similar to hippo's first link there, though cone-shaped and integrated up-down threads. [FarmerJohn, Oct 05 2004]



       Spiral escalator used as a replacement for lifts in the London Underground (re- using the vertical shafts).
timbeau, May 02 2004

       Read the idea again, and you'll find a different form and technology.
FarmerJohn, May 02 2004

       wow, this was a tough idea to visualize. I had issues with the platforms recycling until I saw [hippo]'s first link. That is taken care of, but now I too have an issue with the "down" part. Escalators work so well because they have a leisurely travel rate which allows the average person to transition from standing to walking without too much trippng involved. Here in the states, by law, that speed can be no more than .45 meters per second. Assuming this speed on the way up, geometry tells us that passengers coming down would be traveling at roughly 1.82 meters per second in order to both counteract the screws upward force, as well as make enough progress downward to not cause a log-jam of people waiting to go down. That's leg breaking speed for even a healthy adult. Even presupposing a braking system to slow down passengers upon their eventual exit, the distance between platforms on the down screw would have to be almost 3 times as far apart as on the upside, and that would mean a que of passengers trying to get back down. I think [FarmerJohn] may have foreseen this, so I withold my vote till he gives us some more details.
eyeguy, May 02 2004

       [eyeguy] If we say an up rider is moving 0.45 mps relative to the screw (and 0 mps relative to an external observer), then a down rider could move 0.45 mps relative to the screw in the other direction (0.9 mps relative to an observer) to make similar vertical progress.   

       An observer on the turning screw would see up riders and down riders passing at the same speed in opposite directions. This tells me that the need for platforms on both threads is the same per meter, meaning no queues. Of course some sort of top acceleration and bottom deceleration zones would be needed for down passengers.
FarmerJohn, May 02 2004

       This would be fun to build.
Perchance a quick sketch?

       so on the down screw (giggles childishly), how do you manage the platforms? They have to be going .90 mps relative to the passenger so they can get on, accelerate to 1.35 mps to make headway against the up-going screw (giggles again), then decelerate to .90 mps so the passenger can get off again. Inevitably there would be imbalance in the amount of people it could bring up vs. the amount it could bring down, not to mention the complexity of keeping the passanger platform behind the currently exiting one from slamming into the one ahead it. Hey! can it have three blades? Two for going down and 1 going up? Wait, one more thing... "downward screw" (giggles with maniacal childish laughter yet again).
eyeguy, May 02 2004

       [eyeguy] I still see a start acceleration zone 0.45 to 0.9 mps only and an end deceleration zone to 0.45 as sufficient, and the platforms only near each other at start and end.
FarmerJohn, May 03 2004

       in that case I think I have no further issues with this idea, seems complicated, but workable. And who wouldn't want to ride a pyramidal turning thingy in the mall. For free no less. +
eyeguy, May 03 2004

       This would be really kewl. ++
sartep, May 03 2004


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