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-   -   Inclined lift at Greenford Station replaces the last wooden escalator (https://www.londonbanter.co.uk/london-transport/14633-inclined-lift-greenford-station-replaces.html)

danny burstein November 15th 15 01:48 PM

Inclined lift at Greenford Station replaces the last wooden escalator
 
In e27002 aurora writes:

On Sat, 14 Nov 2015 09:03:03 +0000, Chris J Dixon
wrote:


Basil Jet wrote:

https://www.youtube.com/watch?v=sxScXvX1Dv4


I'm a little surprised that they claim it uses less power than a
conventional lift. If you have to raise a given mass through a
given vertical distance, shouldn't the answer be the same?


It is a funicular railway, no?


I haven't seen the earlier parts of this thread (grumble usenet)
but just as a side comment:

If you're looking for a wooden escalator come to NYC. Some
of the escalators at the Macy's flagship store at 34th
street and sixth avenue are still using woooden treads.

--
__________________________________________________ ___
Knowledge may be power, but communications is the key

[to foil spammers, my address has been double rot-13 encoded]

[email protected] November 15th 15 02:34 PM

Inclined lift at Greenford Station replaces the last wooden escalator
 
In article ,
(Recliner) wrote:

On Sun, 15 Nov 2015 01:34:26 -0800 (PST), Offramp
wrote:

On Sunday, 15 November 2015 02:01:27 UTC, Ken Ward wrote:
On 14/11/2015 09:03, Chris J Dixon wrote:
Basil Jet wrote:

https://www.youtube.com/watch?v=sxScXvX1Dv4

I'm a little surprised that they claim it uses less power than a
conventional lift. If you have to raise a given mass through a
given vertical distance, shouldn't the answer be the same?


Some form of energy recovery on down cycle maybe?


I see no reason why it shouldn't freewheel on the down journey, as long
as there were strong enough buffers at the bottom. It is not FAR, is it?


What makes you think it *could* freewheel down? In most cases, the
lift+payload will be lighter than the counter-weight.


That's alright. Then it can freewheel up.

--
Colin Rosenstiel

Recliner[_3_] November 15th 15 02:51 PM

Inclined lift at Greenford Station replaces the lastwooden escalator
 
danny burstein wrote:
In e27002 aurora writes:

On Sat, 14 Nov 2015 09:03:03 +0000, Chris J Dixon
wrote:


Basil Jet wrote:

https://www.youtube.com/watch?v=sxScXvX1Dv4

I'm a little surprised that they claim it uses less power than a
conventional lift. If you have to raise a given mass through a
given vertical distance, shouldn't the answer be the same?


It is a funicular railway, no?


I haven't seen the earlier parts of this thread (grumble usenet)
but just as a side comment:

If you're looking for a wooden escalator come to NYC. Some
of the escalators at the Macy's flagship store at 34th
street and sixth avenue are still using woooden treads.


The ban on wooden panels and treads on LU was for fire protection reasons
in underground stations. As Greenford is above ground, the wood panels
remained long after they were removed from underground escalators.


Basil Jet[_4_] November 15th 15 02:51 PM

Inclined lift at Greenford Station replaces the last woodenescalator
 
On 2015\11\15 15:34, wrote:
In article ,
(Recliner) wrote:

On Sun, 15 Nov 2015 01:34:26 -0800 (PST), Offramp
wrote:

On Sunday, 15 November 2015 02:01:27 UTC, Ken Ward wrote:
On 14/11/2015 09:03, Chris J Dixon wrote:
Basil Jet wrote:

https://www.youtube.com/watch?v=sxScXvX1Dv4

I'm a little surprised that they claim it uses less power than a
conventional lift. If you have to raise a given mass through a
given vertical distance, shouldn't the answer be the same?


Some form of energy recovery on down cycle maybe?

I see no reason why it shouldn't freewheel on the down journey, as long
as there were strong enough buffers at the bottom. It is not FAR, is it?


What makes you think it *could* freewheel down? In most cases, the
lift+payload will be lighter than the counter-weight.


That's alright. Then it can freewheel up.


I wonder if the counterweight balances a half-laden cabin, or an
averagely-laden cabin (which would presumably be much lighter).

Recliner[_3_] November 15th 15 03:01 PM

Inclined lift at Greenford Station replaces the lastwooden escalator
 
Basil Jet wrote:
On 2015\11\15 15:34, wrote:
In article ,
(Recliner) wrote:

On Sun, 15 Nov 2015 01:34:26 -0800 (PST), Offramp
wrote:

On Sunday, 15 November 2015 02:01:27 UTC, Ken Ward wrote:
On 14/11/2015 09:03, Chris J Dixon wrote:
Basil Jet wrote:

https://www.youtube.com/watch?v=sxScXvX1Dv4

I'm a little surprised that they claim it uses less power than a
conventional lift. If you have to raise a given mass through a
given vertical distance, shouldn't the answer be the same?


Some form of energy recovery on down cycle maybe?

I see no reason why it shouldn't freewheel on the down journey, as long
as there were strong enough buffers at the bottom. It is not FAR, is it?

What makes you think it *could* freewheel down? In most cases, the
lift+payload will be lighter than the counter-weight.


That's alright. Then it can freewheel up.


I wonder if the counterweight balances a half-laden cabin, or an
averagely-laden cabin (which would presumably be much lighter).


This was what the original feasibility study proposed:

- Payload: 1000kg
- Cabin weight: 1400kg
- Counterweight: 1900kg

So the counterweight in the actual lift (which has a smaller payload than
the proposed version) most probably balances a half-laden cabin. That way,
you minimise the required motor torque.


Basil Jet[_4_] November 15th 15 03:18 PM

Inclined lift at Greenford Station replaces the last woodenescalator
 
On 2015\11\15 16:01, Recliner wrote:
Basil Jet wrote:

I wonder if the counterweight balances a half-laden cabin, or an
averagely-laden cabin (which would presumably be much lighter).


This was what the original feasibility study proposed:

- Payload: 1000kg
- Cabin weight: 1400kg
- Counterweight: 1900kg

So the counterweight in the actual lift (which has a smaller payload than
the proposed version) most probably balances a half-laden cabin. That way,
you minimise the required motor torque.


.... but not the total energy consumption, which would be minimised if
the counterweight matched the cabin plus one teenager, since the payload
will typically alternate between empty and 1 woman + 1 child + 1 pushchair.

Basil Jet[_4_] November 15th 15 03:19 PM

Inclined lift at Greenford Station replaces the last woodenescalator
 
On 2015\11\15 16:18, Basil Jet wrote:
On 2015\11\15 16:01, Recliner wrote:
Basil Jet wrote:

I wonder if the counterweight balances a half-laden cabin, or an
averagely-laden cabin (which would presumably be much lighter).


This was what the original feasibility study proposed:

- Payload: 1000kg
- Cabin weight: 1400kg
- Counterweight: 1900kg

So the counterweight in the actual lift (which has a smaller payload than
the proposed version) most probably balances a half-laden cabin. That
way,
you minimise the required motor torque.


... but not the total energy consumption, which would be minimised if
the counterweight matched the cabin plus one teenager, since the payload
will typically alternate between empty and 1 woman + 1 child + 1 pushchair.


Sorry, forgot to say "thanks" for answering my question.

[email protected] November 15th 15 05:38 PM

Inclined lift at Greenford Station replaces the last wooden escalator
 
It is far too long since I did Applied Maths at school but surely the "track" at least partially supports the weight which is otherwise completely supported by the cables in the case of a conventional lift. Surely the work done is much less for this reason ? I'm sure sines or some other algebraic magic are involved in the calculations but 60 years have dulled my memory !!

Recliner[_3_] November 15th 15 07:23 PM

Inclined lift at Greenford Station replaces the lastwooden escalator
 
wrote:
It is far too long since I did Applied Maths at school but surely the
"track" at least partially supports the weight which is otherwise
completely supported by the cables in the case of a conventional lift.
Surely the work done is much less for this reason ? I'm sure sines or
some other algebraic magic are involved in the calculations but 60 years
have dulled my memory !!


Ignoring friction, the work consists of raising and lowering the cabin
between ground and platform level. So in a frictionless world, there would
be no difference whatever between an inclined and a vertical lift. But
because it's not a frictionless world, there is also work to be done
overcoming the friction because it also moves a horizontal distance on
tracks, so there is more work to be done in an inclined than a vertical
lift.

Your confusion is because you're getting the lower *force* in the cables in
an inclined lift mixed up with the greater *work* to be done in both
lifting the cabin and overcoming the friction of the rollers. The lower
force means that the motor needs less power and torque, but more energy is
nevertheless expended over the longer distance and time.

Dr J R Stockton[_41_] November 15th 15 09:33 PM

Inclined lift at Greenford Station replaces the last wooden escalator
 
In uk.transport.london message
om, Sat, 14 Nov 2015 09:16:38, e27002 aurora posted:

On Sat, 14 Nov 2015 09:03:03 +0000, Chris J Dixon
wrote:

Basil Jet wrote:

https://www.youtube.com/watch?v=sxScXvX1Dv4


I'm a little surprised that they claim it uses less power than a
conventional lift. If you have to raise a given mass through a
given vertical distance, shouldn't the answer be the same?


It is a funicular railway, no?



According to the beginning of
https://en.wikipedia.org/wiki/Funicular#Inclined_lift, a funicular must
have two cars - but other parts of the article ignore that.

--
(c) John Stockton, Surrey, UK. Turnpike v6.05 MIME.
Merlyn Web Site - FAQish topics, acronyms, & links.




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