One problem with tall buildings is having enough elevator capacity. The obvious solution is to have lots of elevators, but as buildings become taller, a larger precentage of the square footage must gets used for elevator shafts in order to maintain the same level of service.

If each shaft was dedicated to either up or down (this was inspired by the details of [AO's] Private Elevator idea, but is applied here for slightly more conventional elevators), then there could be more than one elevator per shaft. So the taller a building is, the more vertical space there is in each shaft, allowing more elevators to share the same shaft. This lets the elevator system scale up with the building height much better.

The elevator mechanism would be quite different from a conventional elevator, so designing the system along with all the appropriate safety systems could be expensive, but it wouldn't need to use any exotic technology.

The control of the elevators would be an interesting problem as well. The elevators should be spaced far enough apart and the stops coordinated so one elevator doesn't have to stop and wait for another unless someone blocks the door for too long. In that case the following elevator would need to gently slow and/or stop, preferably informing the passengers of the reason for stopping. If one elevator got stuck or damaged (or the door was being held for a very long time), the other elevators sharing the same shaft would need to inform the passengers and let them out so they could find a shaft that wasn't blocked. This probably wouldn't be practical for a building with only two safts, but if it were used, and one shaft got blocked, all but one elevator would need to hang out in the blocked shaft while the remaining elevator went up and down the one unblocked shaft like a standard elevator. The elevator control system would probably apply many existing techniques such as an expess shaft that will skip some range of floors, and HB "Intelligent Elevator" technology to avoid stopping to pick up more passengers when the elevator is full.
-- scad mientist, May 14 2003

Odyssey System (PDF) http://www.barkermo...tal%20Transport.pdf
Multiple elevators per shaft thing. [tongpoo, Oct 05 2004]

Continuous Elevator http://www.precisio...inuous-elevator.gif
My take on the idea; more continuous--[edit] Whoops! Baked as "paternoster" lift ages ago! [ConsultingDetective, Oct 05 2004]

Personal Elevator (with Toilet) http://www.halfbake...tor_20with_20Toilet
My other elevator idea [ConsultingDetective, Oct 05 2004]

Paternoster, or Cyclic Elevator http://www.dartford...ied/cyclic_elev.htm
Damned ingenious of the Victorians, by jove [ConsultingDetective, Oct 05 2004]

The Citicorp Building in New York City has double height elevators: they stop at two floors at once. So you have to choose either even floors or odd floors, and ne'er the twain shall meet. I have *no idea* why they did this.

There is a well-established idea for free-running elevators that do not hang from cables. These can go up, down and sideways, changing elevator shafts as necessary (at cross-over points), and can run with several cabs in one shaft. I don't know if it has been implemented anywhere, but the New York Times had a well-illustrated article on them several years ago.
-- DrCurry, May 14 2003


Are you making that up, Dr? What if you were on an odd floor and wanted to go to an even one? Is there a little elevator inside the double elevator for traveling between the odd and even levels?
-- AO, May 14 2003


Take a flight of stairs, I guess.
-- snarfyguy, May 14 2003


It's got my vote. The only trouble is that the architects will start to put in less lift shafts and we'll end up waiting just as long anyway.
-- scubadooper, May 14 2003


AO: I kid you not.
-- DrCurry, May 14 2003


For an elevator that needs to be repaired, you could have the top and bottom floors of the building dedicated to the maitenance of the elevators. Simply pull the broken one out of the shaft on one of these floors, depending if it's on the top or bottom, leaving the rest of the shaft open for the still operable one.
-- goober, May 14 2003


don't ask me what I thought this was at first glance.

someone churn double-helix (elevators) escalators for me (whoops.)
-- po, May 14 2003


The problem with multiple cabs per shaftway is the ropes. The cab above will get in the way of the ropes for the cab below. The Odyssey System by Otis resolves this problem by having the elevator cabs horizontally move between lifts. Prepare to be shocked by <a href="http://www.businessweek.com/1997/45/b3552084.htm">this Shockwave animation</a>. Also a <a href="http://www.barkermohandas.com/images/Integrated%20Vertical%20&%20Horizontal%20Transport.pdf">PDF on this</a>.
-- tongpoo, Jul 12 2003



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