h a l f b a k e r yThe phrase 'crumpled heap' comes to mind.
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Some multistory residences have elevators, often for the
use of an elderly or disabled person. However, these
elevators
require electricity to work, and in the event of a power
outage could leave a person who is unable to use the
stairs
stranded—particularly if they need to go up.
However,
if the elevator required no electricity to run,
this problem could be avoided. Hence, in this design the
elevator
car sits atop a hydraulic column, and inside the car there
is a toggle lever that operates two valves: one to let
water out
of the column, and one to supply pressurized water to
the column from a gas boiler. Since no electricity is
required to
operate the elevator, its function will be unimpeded in
the event of a blackout.
How Elevators Work
http://science.hows...pment/elevator1.htm
For your edification, [Twizz] [ytk, Sep 29 2011]
Hoses rated for 1,500 degrees F and up to 12,000 psi
http://www.ushoseco...ey/3/productID/1558
The first result on a Google search for "high temperature high pressure hose" [ytk, Sep 30 2011]
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Annotation:
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Why use a boiler? Mains water pressure could lift the car on it's way to a header tank, from which it feeds the building's water supply. |
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There are other issues with the idea. How do you maintain lighting, control systems, safety systems etc. without electricity? All are possible, but make for a very complex and expensive system. |
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I suggest that 8th's self contained steam elevator makes this idea redundant. The steam engine may have it's own generator for lighting and all the control and safety is taken care of by the driver. |
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I doubt mains water pressure would be sufficient
to force water into the hydraulic column. You'd
need a fair amount of pressure, since you have to
overcome the weight of the elevator. This would
normally be provided by an electric pump. |
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Lighting could be provided electrically, since it's
not intrinsic to the operation of the elevator. In
the event of a power outage, you'd use a
flashlight, just like you'd use in any other room of
the house. Lighting could also be provided by a
skylight. |
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The controls are very simple: up and down. The
lever simply opens up one valve or the other to
determine the direction of travel. |
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Hydraulic elevators are intrinsically safe from
falling, since they are designed to fail in such a
way that the hydraulic fluid leaks out slowly. As
for being able to move the car when the door is
open, simply design the valve so that the inner
door has to be closed in order for it to be moved
from the neutral position, by means of a
mechanical block. Design the outer door so that
it meshes with the inner door, and can only be
opened or closed at the same time as it. |
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/I suggest that 8th's self contained steam elevator
makes this idea redundant./ |
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Umm... I guess, in the same way that the
Hullaballoon makes the dirigible redundant.
Nothing against 8th's idea, but my idea attempts
to solve a real-life practical problem—namely,
people with disabilities being unable to navigate
their own homes. |
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This could be done more elegantly with an Otto or Crossley engine ... or even a simple single-shot cylinder-and-piston arrangement ... but we will award a bun for a worthwhile objective. |
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Water pressure is sufficient to lift water, which is of a considerably higher density than a lift car. You just need an appropriate cylinder diameter. |
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"Lighting.... not intrinsic to the operation of the elevator" |
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I suspect building regulations have a different view on this. |
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"The controls are very simple: up and down" |
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So how do the valves in the (moving) car control admission of water pressure to the (static) cylinder? |
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All lifts (elevators) made in the last 100 years or so are safe from falling. It's a fairly basic requirement. |
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8th's idea is for a self contained steam elevator. It is the self contained element of the idea which makes it independent of electrical supply. |
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When did you last see a boiler that didn't use an electric control? An installation in any building will require interlocks. |
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As I said before, it's all possible, but it's a really complex way of going about it. No less complex than a steam elevator. |
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//So how do the valves in the (moving) car control admission of water pressure to the (static) cylinder?// |
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You're simply fishing. Flexible hoses, hydraulic circuits, any number of methods. |
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/Water pressure is sufficient to lift water, which is of a considerably higher density than a lift
car. You just need an appropriate cylinder diameter./ |
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The density of the car is irrelevant, since the car's not floating on the water. What is of
importance is the back pressure at the inlet valve, which is determined solely by mass, not
volume. Assuming a very good water pressure of 5 bar, a column of water 20 cm in diameter
would be able to lift roughly 310 kg. That's including the car, the passengers, the hydraulic
column, and the mass of the water itself. Drop that down to 3 bar, and you're only looking at
186 kg. You could make the column diameter larger, but the larger you make it the slower the
elevator will operate. |
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/I suspect building regulations have a different view on this./ |
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As I said, you could still equip the elevator with an electric light. The point is that if the
electricity goes out, the elevator could still function without the lights. If you needed light,
you could just use a flashlight, or a lantern, or a candle, or a flaming pair of pants for that
matter. It's no different from any other room in the house in this regard. |
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/When did you last see a boiler that didn't use an electric control?/ |
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Gas water heaters don't require electricity to keep running, assuming the gas pilot light stays
on. A simple boiler that is designed to maintain a constant water pressure at the exit valve
without the use of electricity could be easily designed and built. Anyway, the boiler isn't
central to the idea. You could replace that stage with a natural gas powered pump, and those
can even be bought on Amazon. |
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Surely all of this discussion is amyptoting towards a
fireman's pole/tramoline combo? |
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Right - words of one syl... in simpler terms. |
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I am making the reasonable assumption that a multistorey residence has a water supply to the top floor. |
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I am also making the reasonable assumption that the lift car would be counterbalanced, so all we need to do is offset the weight differential and friction. |
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The simple approach would be to fit a tank to the lift car, supply water through low pressure hoses and adjust water mass at the lift car to control it's ascent / descent. |
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Long flexible hoses carrying high pressure boiling water are not a practical proposition. |
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A long hydraulic column is impractical. You'd either need to house it in a pit as deep as the height of the building, or have it sticking out above the building. A hydraulic actuator when fully extended is at least double the length of it's travel. I have seen hydraulic column lifts, but only operating over a couple of floors. There are also engineering issues, such as long column buckling and manufacture of a very long ram, to deal with. |
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Would you run your boiler continuously, or would you wait while a large mass of water is heated (by which time the power will probably be back on). |
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I guess my overall point is that this is a very complex, expensive and impractical solution to a problem that could be much better solved by not housing people with mobility problems at the top of high rise blocks. |
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The idea falls between the amusing and the realistic. |
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//attempts to solve a real-life practical problem—namely, people with disabilities being unable to navigate their own homes// |
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Is THAT what this is about? How about shooting them out of a circus cannon at the bottom of the stairs... and if they want to come back down, just use the slide. Frankly, I don't even see a need for the stairs. This is a sensitive subject for me, because I myself have a disability (that is, I can't pronounce anything with a diphthong in it without laughing. Very debilitating, that.) |
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Still, I'm giving you a bun for hatching a truly halfbaked idea. [+] I am interested to know when these will be commercially available. I will buy one and convert it into a circus cannon. |
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Really the problem here is the problem of unpredictable electricity service and an attempt to make a workaround using the gas supply to the house. It is a problem more general than that of persons with disabilities requiring electrical devices. For the elevator - rather than use gas for a dedicated boiler and separate hydraulics, why not have a gas powered generator? |
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Taking this idea to its logical extreme there would be a gas powered generator (capable of using natural gas from the house line or LP gas, of which there is a canister handy) on the roof, together with solar panels, batteries and a giant water tank which is filled by main water pressure. The house can come off the grid and run on battery power. Batteries can be charged by solar, electricity, natural gas or LP gas. They can also be charged by the downflow of water from the tank. A fully charged battery would serve to operate aforementioned elevator for several cycles; off the grid the occupant might need to wait on the the elevator until batteries recharge from gas or solar. |
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In addition to charging battery with release and downflow of water, should solar/gas/LP gas be unavailable, the rooftop tank serves as a water supply in the event of catastrophe, both for personal use as well as fighting fires. |
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The batteries are also attached to devices (eg: Thighmaster, War Pogostick) in occupant's rooftop exercise suite, so as not to waste calories burned during personal betterment. These devices could also be run as a sort of rent payment by persons taking refuge with the occupant after the fall of civilization. |
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In the event of zombie apocalypse, the treadmill (probably not the Thighmaster) could be run by captive zombies with succulent brains or brain-containing volunteer placed before them as an incentivizing carrot. |
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The elevator in such a house should be balanced with the person's net weight, ie: including wheelchair if applicable, so manual power requirements are minimal. |
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/I am also making the reasonable assumption that the lift car would
be counterbalanced, so all we need to do is offset the weight
differential and friction./ |
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Ah, so you don't know what you're talking about. That explains a
lot, really. Hydraulic elevators, in general, are not
counterweighted. That's kind of the point of them. |
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/A long hydraulic column is impractical. You'd either need to house
it in a pit as deep as the height of the building, or have it sticking
out above the building./ |
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And yet, that's how every single hydraulic elevator works—the
column extends into a pit in the ground roughly equal in depth to
the height of the building. I'll go tell the elevator manufacturers
you said that's impractical, though. |
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/Long flexible hoses carrying high pressure boiling water are not a
practical proposition./ |
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Why not? But even if that were the case, there are plenty of other
ways of achieving the same functionality. The valves could be
operated by fluid control lines, like a car's brake line. Or you could
use a natural gas pump as I suggested above, which wouldn't heat
the water at all. |
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/I guess my overall point is that this is a very complex, expensive
and impractical solution to a problem that could be much better
solved by not housing people with mobility problems at the top of
high rise blocks./ |
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Right, let's just deny access to the disabled because it's
inconvenient for us to make things accessible. |
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/Is THAT what this is about? How about shooting them out of a
circus cannon at the bottom of the stairs.../ |
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Yeah, hilarious. Try talking to someone with a real disability
sometime and see how funny it is for them. Have you ever been
stranded in a subway station because the elevator wasn't working,
and there were no more trains coming? That actually happened to
someone I know, and it wasn't nearly as funny as you make it out to
be. |
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//...Try talking to someone with a *real* disability sometime...// |
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And you don't think my Diphthong Hypersensitivity is a real disability? See if I ever step into YOUR elevator! I bet it's crawling with diphthongs. |
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Instead of a gas boiler, consider having high and low
pressure hydraulic reservoirs, a variable displacement
hydraulic motor, and a variable displacement hydraulic
pump. |
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The high pressure reservoir's pressure will always be
higher than that of the cylinder; the low pressure
reservoir's pressure will always be lower than that of
the cylinder. |
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When the elevator needs to rise, hydraulic fluid passes
from the high pressure reservoir, through the rotary
hydraulic motor, to the cylinder. The mechanical power
produced by that motor is used to turn the pump, which
moves fluid from the low pressure reservoir to the
cylinder; this dissipates the mechanical power in a
useful manner. The displacement of the motor and
pump are both adjusted as needed, to modulate the rate
hydraulic fluid flow into the cylinder, to avoid a sudden
start or stop of the elevator compartment. |
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When the elevator needs to descend, hydraulic fluid
passes from the cylinder, though the hydraulic motor,
into the low pressure reservoir. The mechanical power
produced by the motor is used to drive the pump, which
moves fluid from the cylinder to the high pressure
reservoir. As before, the displacement of the motor
and pump are both adjusted as needed to modulate rate
of removal of fluid from the cylinder. |
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If there were no energy losses, such a system could
operate indefinitely, without needing outside energy --
assuming that everything which goes up in the elevator
eventually goes back down. In the real world, there is
friction, head loss, leakage, pump inefficiency... plus
there are people who will ride the elevator up, then
walk down. |
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As needed, a gas or electric motor will drive the
hydraulic pump, to move hydraulic fluid from the low
pressure reservoir to the high pressure reservoir. |
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The system also would contain a battery, kept charged
using mains electricity, which would provide lights for
the elevator cabin, power for the door, and power for
the controls. |
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"Ah, so you don't know what you're talking about" |
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Resorting to personal insult does not help your case. |
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I'm a design engineer working mostly with hydraulic systems, so I might have a clue. |
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The highest hydraulic elevator I'm aware of goes 7 floors. Hydraulic elevators are largely a fashionable gimmic, not a practical solution. |
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Try sourcing hoses to carry high pressure, high temperature fluids - you'll soon see the problem. |
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My opposition to an overcomplicated solution cannot be interpreted as a rejection of the need for any solution. |
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A close friend lost a leg in a road accident some years ago. Rather than demand or create a bunch of complex machinery, he moved from his high rise flat to a ground floor flat. In the UK we still have enough of a social housing system to make this possible. |
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Once again, nothing in the original idea is impossible. It's just not practical. |
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/Resorting to personal insult does not help your case./ |
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/Right - words of one syl... in simpler terms./ |
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Uh huh. And saying you don't know what you're talking about when you are making
statements that are clearly
and demonstrably wrong is hardly an insult. |
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/I'm a design engineer working mostly with hydraulic systems, so I might have a
clue./ |
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Who are you trying to impress with your argument from authority? I've met plenty of
people who purport to be
experts in their field who clearly have no idea what they're talking about. Actually,
it's usually the case that the
ones who are most ignorant invoke their job titles as the basis for their expertise. |
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/The highest hydraulic elevator I'm aware of goes 7 floors./ |
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Seven floors is plenty. I'm talking about an elevator in a two or three story home,
not a high-rise apartment
building. |
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/Hydraulic elevators are largely a fashionable gimmic, not a practical solution./ |
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Hydraulic elevators have been in common usage for decades, and have proven quite
reliable, efficient, and safe.
They're simpler to install and maintain than counterweighted elevators, and are ideal
for buildings that only
have a few floors. I live in Los Angeles, where buildings rarely exceed three or four
stories, and hydraulic
elevators are by far the most common type I encounter. |
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/Try sourcing hoses to carry high pressure, high temperature fluids - you'll soon see
the problem./ |
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Huh? A quick Google search revealed quite a few companies willing to manufacture
and sell such a thing. |
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/A close friend lost a leg in a road accident some years ago. Rather than demand or
create a bunch of complex
machinery, he moved from his high rise flat to a ground floor flat. In the UK we still
have enough of a social
housing system to make this possible./ |
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So? Does that mean that disabled people should have to accept either living in single
story homes, or the
possibility of being stranded in the event of a power outage? I don't know about the
UK, but in the US, we have
a culture—and laws to back it up—that says that marginalizing the disabled is
unacceptable. |
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/Once again, nothing in the original idea is impossible. It's just not practical./ |
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Given that this idea is really just a slight variation on the basic hydraulic elevator, so
that it is capable of operating completely without electricity, I don't see what's so
impractical about it. Your objections seem to be more directed toward the concept
of the hydraulic elevator itself. |
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