how do lifts work/stop working?
 

i visuallise a lift as a cage; a motor; a cable and a switch. why do
they get stuck?

why do they get stuck in between floors?

do you try to exit lifts stuck between floors? or do you fear
decapitation/amputation from a sudden motion of the lift?

thanks.
k

how do lifts work/stop working?
 

"komodore comrade" wrote in message
oups.com...
i visuallise a lift as a cage; a motor; a cable and a switch. why do
they get stuck?

why do they get stuck in between floors?

do you try to exit lifts stuck between floors? or do you fear
decapitation/amputation from a sudden motion of the lift?

thanks.


Lift have a built in safty mechanism such that if the cable breaks
(ie the lift freefalls, an automatic break is applied. (basically the
tension in the
cable stops some 'rods' from sticking into a 'grid' in the shaft wall..))

Best to wait to be rescued methinks!!

how do lifts work/stop working?
 

In article .com,
"komodore comrade" writes:
i visuallise a lift as a cage; a motor; a cable and a switch. why do
they get stuck?

why do they get stuck in between floors?

Usually because one of the safety detectors triggers.

do you try to exit lifts stuck between floors? or do you fear
decapitation/amputation from a sudden motion of the lift?

Reminds me of that wonderful lift shaft scene in The Omen II

--
Andrew Gabriel

how do lifts work/stop working?
 

Most lifts have a steel cable from the car to the top of the liftshaft
where it has multiple turns around a pulley on the motor shaft and then
is connect to the counterweight running in the shaft next to (and in
the opposite direction to) the lift car (yes I had a look in that room
that says "danger - do not enter"). Lift problems are often about the
large number of safety interlocks, and I'd expect one on the escape
door on the roof of the lift car too.

how do lifts work/stop working?
 

On Fri, 25 Aug 2006 21:25:47 GMT, "Bazzer Smith"
wrote:


"komodore comrade" wrote in message
roups.com...
i visuallise a lift as a cage; a motor; a cable and a switch. why do
they get stuck?

why do they get stuck in between floors?

do you try to exit lifts stuck between floors? or do you fear
decapitation/amputation from a sudden motion of the lift?

thanks.


Lift have a built in safty mechanism such that if the cable breaks
(ie the lift freefalls, an automatic break is applied. (basically the
tension in the
cable stops some 'rods' from sticking into a 'grid' in the shaft wall..))

Known (at least in mining circles) as a "keps" (probably a corruption
of "keeps"), and usually operated by a centrifugal gizmo.

--
Frank Erskine

how do lifts work/stop working?
 

"Frank Erskine" wrote in message
...
On Fri, 25 Aug 2006 21:25:47 GMT, "Bazzer Smith"
wrote:


"komodore comrade" wrote in message
groups.com...
i visuallise a lift as a cage; a motor; a cable and a switch. why do
they get stuck?

why do they get stuck in between floors?

do you try to exit lifts stuck between floors? or do you fear
decapitation/amputation from a sudden motion of the lift?

thanks.


Lift have a built in safty mechanism such that if the cable breaks
(ie the lift freefalls, an automatic break is applied. (basically the
tension in the
cable stops some 'rods' from sticking into a 'grid' in the shaft wall..))

Known (at least in mining circles) as a "keps" (probably a corruption
of "keeps"), and usually operated by a centrifugal gizmo.

Yes thats correct, I actually was thinking of some sort of cantilever
system,
where the tension in the cantilevers pulled the rods back (like the tension
in
a pulled longbow makes it shorter), However I was just thinking that if the
bow
'broke' you might be in serious trouble!!
At least that is what I recall seeing on some television program about the
first
lift, where the inventor convinced people of its safety by being in the lift
when
the rope was cut!!!

What you are perhaps describbing is perhaps more similar to this ?
http://science.howstuffworks.com/elevator5.htm

The method I was thinking off doesn't seem to be described there, so maybe
it
is no longer used.
However I guess any method with moving parts can fail, and apparently there
is a
heavy duty shock absorber at the bottom of the shaft "just in case"!!!

how do lifts work/stop working?
 

On Fri, 25 Aug 2006 21:50:26 UTC, (Andrew
Gabriel) wrote:

Reminds me of that wonderful lift shaft scene in The Omen II

I prefer the one in Dark Star!

--
The information contained in this post is copyright the
poster, and specifically may not be published in, or used by
Avenue Supplies, http://avenuesupplies.co.uk

how do lifts work/stop working?
 

In article ,
Frank Erskine writes:
On Fri, 25 Aug 2006 21:25:47 GMT, "Bazzer Smith"
wrote:
Lift have a built in safty mechanism such that if the cable breaks
(ie the lift freefalls, an automatic break is applied. (basically the
tension in the
cable stops some 'rods' from sticking into a 'grid' in the shaft wall..))

Known (at least in mining circles) as a "keps" (probably a corruption
of "keeps"), and usually operated by a centrifugal gizmo.

Yep -- one of these in the Empire State Building got exercised
back in 1995 with a lift car full of Japanese tourists, only
about 3 days after I travelled in it. Reports at the time said
it slipped a couple of floors before jamming.

--
Andrew Gabriel

how do lifts work/stop working?
 

Many fail due to the power tripping for a multitute of reasons - but most
places call out the lift engineer to re-set it. Been waiting for 2 weeks at
my place of work - it hasn't worked since the power was off for some other
work. I guess it will be a simple reset that is required.

how do lifts work/stop working?
 

"komodore comrade" wrote in message
oups.com...
i visuallise a lift as a cage; a motor; a cable and a switch.

Motorised lifts are much like that, except they usually have multiple cables
and a counterweight. There are also lots of switches, mainly to do with
safety. Hydraulic lifts usually have a big hydraulic cylinder up the back of
the shaft, with the cables running over a pulleys on the top, attached to
the lift at one end and to something solid at the other. Hydraulic lifts are
better at getting the floor of the lift level with the floor outside, so are
often used where most traffic is wheeled - hospital lifts and freight lifts,
for example.

why do
they get stuck?

Usually because one of the safety switches trips.

do you try to exit lifts stuck between floors? or do you fear
decapitation/amputation from a sudden motion of the lift?

The escape hatch is in the roof, so decapitation is not usually likely.
However, the right procedure is to press the alarm button and wait.

Colin Bignell

how do lifts work/stop working?
 

" wrote in
oups.com:

Lift problems are often about the
large number of safety interlocks, and I'd expect one on the escape
door on the roof of the lift car too.


Do escape doors on the top of lift cars exist outside Hollywood?

I've never seen one, I can't imagine what good one would be - what to you
do now you're standing among the cables and pulleys?

The nearest I've seen is on the London Underground, so long ago they're
probably replaced, where lifts could be placed side by side in the shaft
and passengers transferred, but this was all under manual control by staff.

mike

how do lifts work/stop working?
 

On 26 Aug 2006 10:47:19 GMT, mike wrote:


Do escape doors on the top of lift cars exist outside Hollywood?


Maybe they're also for maintenance.

I've never seen one, I can't imagine what good one would be - what to you
do now you're standing among the cables and pulleys?


The firemen could get you out with a couple of ladders to the floor
above.

There used to one in the lift when I went to UNI. It was a 9 floor
building, at lunchtimes and at the end of the day there used to be
long queues for the lift at every floor, the car which was already
full used to stop and open it's doors at every floor. Merely tripping
the microswitch on the hatch caused the car to stop and the controller
to do a reset thereby "forgetting" all the pending stops. :-))

The nearest I've seen is on the London Underground, so long ago they're
probably replaced, where lifts could be placed side by side in the shaft
and passengers transferred, but this was all under manual control by staff.


DG

how do lifts work/stop working?
 

"mike" wrote in message
. 1.4...
" wrote in
oups.com:

Lift problems are often about the
large number of safety interlocks, and I'd expect one on the escape
door on the roof of the lift car too.


Do escape doors on the top of lift cars exist outside Hollywood?

Yes, but, as they are for rescuers to get to people in the lift, they often
can only be opened from outside the lift and simply look like a roof panel
from inside.

Colin Bignell

how do lifts work/stop working?
 

Derek ^ wrote:


The firemen could get you out with a couple of ladders to the floor
above.


Not a practical way to get the people out...try firemen going up to the
control room and using the manual winch to bring the lift to the nearest
floor. ;-)

--
Sir Benjamin Middlethwaite

how do lifts work/stop working?
 

On Sat, 26 Aug 2006 14:43:14 GMT, "The3rd Earl Of Derby"
wrote:

Derek ^ wrote:


The firemen could get you out with a couple of ladders to the floor
above.


Not a practical way to get the people out...try firemen going up to the
control room and using the manual winch to bring the lift to the nearest
floor. ;-)

What if it won't move ?

DG

how do lifts work/stop working?
 

Derek ^ wrote:
On Sat, 26 Aug 2006 14:43:14 GMT, "The3rd Earl Of Derby"
wrote:

Derek ^ wrote:


The firemen could get you out with a couple of ladders to the floor
above.


Not a practical way to get the people out...try firemen going up to
the control room and using the manual winch to bring the lift to the
nearest floor. ;-)

What if it won't move ?

DG

Then the guy who designed it should be shot.
A lift does not get stuck,its the electrical circuitry that takes a
wobbler.

--
Sir Benjamin Middlethwaite

how do lifts work/stop working?
 

On Sat, 26 Aug 2006 17:27:34 UTC, "The3rd Earl Of Derby"
wrote:

Derek ^ wrote:
On Sat, 26 Aug 2006 14:43:14 GMT, "The3rd Earl Of Derby"
wrote:

Derek ^ wrote:


The firemen could get you out with a couple of ladders to the floor
above.

Not a practical way to get the people out...try firemen going up to
the control room and using the manual winch to bring the lift to the
nearest floor. ;-)

What if it won't move ?

Then the guy who designed it should be shot.
A lift does not get stuck,its the electrical circuitry that takes a
wobbler.

Not necessarily. As noted earlier, if the cable fails then the cage
locks into its surroundings. In that situation, I guess the ladder is
the only option.

--
The information contained in this post is copyright the
poster, and specifically may not be published in, or used by
Avenue Supplies, http://avenuesupplies.co.uk

how do lifts work/stop working?
 

On Sat, 26 Aug 2006 17:27:34 GMT, "The3rd Earl Of Derby"
wrote:


Not a practical way to get the people out...try firemen going up to
the control room and using the manual winch to bring the lift to the
nearest floor. ;-)

What if it won't move ?

DG

Then the guy who designed it should be shot.
A lift does not get stuck,its the electrical circuitry that takes a
wobbler.

Stranger things have happened ...

Eg, Fork lift driver backs into lift doors which thereafter won't open
and also foul movement of the car.

I frequently see lorries stuck on the motorways because their brakes
have failed safe = on. Would firemen attack the brakes on a lift so
the could winch it down manually (If it were to happen, naturally).

3 men were killed in a mill where I once worked because they rolled a
large flywheel into a lift car which descended uncontrollably.

DG

how do lifts work/stop working?
 

The message
from Derek ^ contains these words:

Not a practical way to get the people out...try firemen going up to the
control room and using the manual winch to bring the lift to the nearest
floor. ;-)

What if it won't move ?

Mostly the safety clamps are held on by the weight of the car. If you're
able to pull up on the lift wires the safetys release.

--
Skipweasel
Pay no attention to that man behind the curtain.

how do lifts work/stop working?
 

"komodore comrade" wrote in message
oups.com...
i visuallise a lift as a cage; a motor; a cable and a switch. why do
they get stuck?

why do they get stuck in between floors?

do you try to exit lifts stuck between floors? or do you fear
decapitation/amputation from a sudden motion of the lift?

So are you texting this from a stuck lift, trying to decide what to do next?

how do lifts work/stop working?
 

"mike" wrote in message
. 1.4...
" wrote in
oups.com:

Lift problems are often about the
large number of safety interlocks, and I'd expect one on the escape
door on the roof of the lift car too.


Do escape doors on the top of lift cars exist outside Hollywood?

Yes they do, but they tend to be locked down in public lifts. The few that I
have seen, have a switch sensor on the panel, that triggers an alarm and
cuts the motor as soon as it is opened. I triggered one once by accident at
university (many years ago) when I knocked the ceiling panel, and it opened
:-( Luckily, the lift reset itself when I closed it again :-)

-- JJ

how do lifts work/stop working?
 

"The3rd Earl Of Derby" wrote in message
k...
Derek ^ wrote:
On Sat, 26 Aug 2006 14:43:14 GMT, "The3rd Earl Of Derby"
wrote:

Derek ^ wrote:


The firemen could get you out with a couple of ladders to the floor
above.


Not a practical way to get the people out...try firemen going up to
the control room and using the manual winch to bring the lift to the
nearest floor. ;-)

What if it won't move ?

DG

Then the guy who designed it should be shot.
A lift does not get stuck,its the electrical circuitry that takes a
wobbler.

Okay, so you shoot him. Then what? The people are still stuck.

how do lifts work/stop working?
 

In article ,
Jim Michaels writes:

The inner doors will not open unless aligned with a set of outer doors

I think this must have changed at some point in the UK.
I've seen a number of lift renovations where the inner door
locks have had to be removed, so you can forcibly open them
at any time. If you do it whilst the lift is moving, it
stops pretty dead -- no gradual deceleration. Outer doors
will not open unless roughly aligned with inner doors though.

--
Andrew Gabriel

how do lifts work/stop working?
 

In message .com,
komodore comrade writes
i visuallise a lift as a cage; a motor; a cable and a switch. why do
they get stuck?

why do they get stuck in between floors?

do you try to exit lifts stuck between floors? or do you fear
decapitation/amputation from a sudden motion of the lift?

You definitely need to keep up with those psychiatric visits


--
geoff

how do lifts work/stop working?
 

Andrew Gabriel wrote:

Reports at the time said
it slipped a couple of floors before jamming.

That's deliberate. If it stopped instantly, the passengers would emerge
shorter.

There's no _need_ to stop instantly. It's a big tall building, there's
plenty of space for a gradual deceleration.