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Posers and Puzzles

Posers and Puzzles

  1. 20 Aug '03 22:13 / 1 edit
    Why do escalators' handrails always run a bit faster than their steps?
    I have to admit I don't know the reason for this, does anyone?
  2. 21 Aug '03 00:10
    Originally posted by iamatiger
    Why do escalators' handrails always run a bit faster than their steps?
    I have to admit I don't know the reason for this, does anyone?


    Is this also the case when the escalator is going down ?

    IvanH.
  3. 21 Aug '03 00:12 / 2 edits
    Originally posted by iamatiger
    Why do escalators' handrails always run a bit faster than their steps?
    I have to admit I don't know the reason for this, does anyone?
    Good question!

    These guys make them and they don't seem to know...

    http://www.fujitec.com.ar/english/information/pages/normas.htm

    In the safety rules for escalators section, item 4...

    4) Re-place your hands if the handrail goes slower or faster than steps.

  4. 21 Aug '03 01:59
    Originally posted by iamatiger
    Why do escalators' handrails always run a bit faster than their steps?
    I have to admit I don't know the reason for this, does anyone?


    I bet the handrails are going faster than the steps when
    the escalator is going up and slower when going down.

    IvanH.
  5. 21 Aug '03 02:43
    I'm guessing it's the same reason the outside of a tire travels a longer distance than the inside. They both make one revolution in the same amount of time, but the outside has further to travel in that time frame, so it has to go faster.
    That's my theory . . .
  6. Donation bbarr
    Chief Justice
    21 Aug '03 02:45
    Originally posted by iamatiger
    Why do escalators' handrails always run a bit faster than their steps?
    I have to admit I don't know the reason for this, does anyone?
    Perhaps so you can retain a firm grip on the handrails while you walk up the escalator like you would a set of stairs. Many people don't merely allow themselves to be passively escalated, but also use their legs (like suckers).
  7. Standard member Fiathahel
    Artist in Drawing
    21 Aug '03 08:30
    Originally posted by iamatiger
    Why do escalators' handrails always run a bit faster than their steps?
    I have to admit I don't know the reason for this, does anyone?
    One posibility is that when noone is one the escalator, they have the same speed. When someone steps onto the escalator, then more power is needed to keep the same speed. If the engine is incapable of giving more power, the steps slow down a bit.

    (you can test this by measuring the relative speed when there's noone (or only you) on the escalator, and measuring it when it is crowded with people)
  8. Standard member TheMaster37
    Kupikupopo!
    21 Aug '03 10:16
    The steps are much heavier in itself, i think that they would go slower on it's own as well...

    And think of the people making the step on/off the escalator. That requires them to make a little speed. Either not to block people behind them or to catch up with the part they want to stand on. With a rail that goes faster, all you need to do it hang on to it to get the right speed...
  9. Standard member TheMaster37
    Kupikupopo!
    21 Aug '03 10:47
    Someone told me this:

    When the rail runs for a while, it wears down because of the friction. Because of that the rails starts to run a little slower.

    What they do is to set the speed of the rail a little higher then the speed of the escalator. After a while is has worn down a bit, so the speed is equal, and after some more time it runs slower. But when it runs slower they re-adjust it to run a little faster (or they replace the rails).
  10. 21 Aug '03 15:41
    I had always assumed that, if they couldn't get the speeds to be the same, it was safer for the handrail to go faster, pulling you forward rather than pushing you back.

    However, that wouldn't apply so well to down escalators, so maybe the 'gets slower as it wears out' explanation is the right one.

    ry
  11. 22 Aug '03 11:22
    Originally posted by ivanhoe


    I bet the handrails are going faster than the steps when
    the escalator is going up and slower when going down.

    IvanH.
    Good theory! Would somebody please do some tests this weekend and report back!
  12. 22 Aug '03 11:45
    Originally posted by iamatiger
    Good theory! Would somebody please do some tests this weekend and report back!
    I forgot to say in my last post: I checked the nearest escalator yesterday and both "up" and "down" have the handrail a bit faster.

    ry
  13. Donation ChessNut
    Lightly Salted...
    22 Aug '03 17:21
    I think it's to give the rider the illusion of speed. Makes them feel like they are going faster than they really are. As humans we are very impatient aren't we?
  14. 22 Aug '03 18:28
    Originally posted by ChessNut
    I think it's to give the rider the illusion of speed. Makes them feel like they are going faster than they really are. As humans we are very impatient aren't we?
    Ok, after some thought my view is this: It is important to make sure that the rider is not sloping backwards when the escalator flattens out as he will then try to regain his balance by taking a step backwards into the person or step behind him, will then fall over, and will probably be sucked into the machinery and die.

    If the handrail goes slower than the steps it will tend make the rider slope backwards, so it's best to err on the safe side and make the handrail a bit faster than the steps. This of course makes the rider slope forwards a bit, but people are not particularly likely to fall over if they are sloping forwards because they can take a step forward to correct their balance, which is the way they want to go anyway.
  15. 15 Sep '03 15:05
    Why not?