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Ghost in a machine ?

  1. Oct 13, 2005 #1

    wolram

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    Can there be such a thing ? at work there is a machine that constantly has
    breakdowns that defy logical explanation, human intervention has been ruled
    out as there are cameras in the room, and the only way the breakdowns could
    be man made is by some with tools and access to the machine
     
  2. jcsd
  3. Oct 13, 2005 #2

    Mk

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    I think its the wol-RAM.
     
  4. Oct 13, 2005 #3

    wolram

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    Ahhhh, no it is a problem i do not need :grumpy:
     
  5. Oct 13, 2005 #4

    Danger

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    No.
    So what kind of machine, and what's going wrong? If things are loosening up, it's probably vibration-related. Likewise if settings are drifting.
     
  6. Oct 13, 2005 #5

    Math Is Hard

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    There is a vending machine on campus that loves me. It gives me extra packages of chips and cookies.
     
  7. Oct 13, 2005 #6

    Danger

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    Don't be fooled! It's only using you to get at your ipod.
     
  8. Oct 13, 2005 #7

    wolram

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    Grrrr, that is naughty, but no this infernal machine some how jumps 1.5 toothed
    belts, that drive load free," other than a small amout of friction" comonents.
     
  9. Oct 13, 2005 #8
    It's called Windows :rofl:.
     
  10. Oct 13, 2005 #9

    wolram

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    One up to motai :rofl: however our company is windows free, unless you count
    a laptop
     
  11. Oct 13, 2005 #10

    Danger

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    So Wooley, are you referring to a 1 1/2 inch Gilmer drive? Does it have a tensioner? Also, unless the pulleys are rimmed, the slightest misalignment of the axles will cause the belt to 'walk off'. A worn bearing could be enough to do it.
     
  12. Oct 13, 2005 #11
    Last edited by a moderator: Apr 21, 2017
  13. Oct 14, 2005 #12

    Math Is Hard

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    oooh...Hypatia! I know how you can get rid of that demon-possessed Halloween novelty in your garage! And make a few bucks, maybe!
     
  14. Oct 14, 2005 #13

    wolram

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    The same style as this only bigger.
    http://www.maplin.co.uk/Free_UK_Delivery/Timing_Pulleys_and_Belts_46676_v2.htm [Broken]

    And the guys who trade these drive systems and advise system design say no way can this happen.
     
    Last edited by a moderator: May 2, 2017
  15. Oct 14, 2005 #14

    Lisa!

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  16. Oct 14, 2005 #15

    wolram

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  17. Oct 14, 2005 #16

    Lisa!

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    :grumpy: :grumpy: Do you think money is more important than your health? I'm sure those ghosts don't like you and they may want to kill you. :rolleyes:
    And I guess your employer is with them or perhaps he's a ghost himself.
    Anyway it's others(:tongue2:) who should be worried about you not me. :wink:
     
  18. Oct 14, 2005 #17

    wolram

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    I think you are looking for a job, what skills do you have ? i may be able to help
    :approve:
     
  19. Oct 14, 2005 #18

    Danger

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    Okay, that's what I was thinking of. The flanges (what I called rims before) should prevent the belt from coming off. If by 'jumping' you just mean 'slipping', it shouldn't be possible unless it's way too loose. Once again I ask if there's a tensioner on it. If not, add one (or maybe even one on each side of the pulley) and see if it helps.
     
  20. Oct 14, 2005 #19

    wolram

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    Sorry, yes there is a tensioner, one pully is driven via a 30mm shaft which
    connects to an 90 degree angle gear box 1:1 ratio, which in turn drives a
    simple rocking mechanism that picks a sleeve from a magazine and places
    it over a product, the sleeve is folded around the product down stream.
    both pullies have 8mm keys or maybe one is 6mm so they can not move on the
    shaft. we locked the mechanism up with a .5inch socket extension bar, the
    belt did not jump the main drive clutch operated first. :confused:
     
  21. Oct 14, 2005 #20

    Danger

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    Sorry, but you're going to have to explain the last part of that in a lot more detail. Partly because I don't know where/what the clutch is, and partly because you sometimes use different terminology than I do, I can't follow what you mean. "locked the mechanism up"? And by "socket extension bar" do you mean one that goes between the ratchet and the socket for more reach, or a snipe for more torque?:confused: :confused: :confused:
     
  22. Oct 14, 2005 #21

    wolram

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    The motor that drives the machine is fitted with a clutch, the output from the
    cluch is linked via .5inch duplex chain to the machine main drive shaft, on the
    other end of the main drive shaft is a 90 degee gear box this gear box drives
    a shaft that runs the length of the machine, this shaft drives various parts of the machine, including the one that is causing the trouble, a toothed pully
    and belt drive a second angle gear box that drives the sleeve pick and place
    mechanism.
    i mean a bar that goes between ratchet and socket for more reach.

    So it is motor clutch fitted at bottom right hand corner of machine, drives a
    shaft above it that runs the width of the machine, then through a 90 degree
    gear box to a shaft that runs the lenght of machine, then a toothed pully
    belt takes drive to 90 degree gear box that is approx three feet above.
     
  23. Oct 14, 2005 #22

    Danger

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    Okay, I've got the lay of the land now. I still don't know what you meant by 'locking the mechanism', though, unless it was to deliberately jam the sleeve-picker thing to try forcing a skip. So it didn't jump, but the clutch slipped instead? Have you thoroughly inspected both pulleys and the belt? There could be a cumulative effect at work. Say you've got a partially worn spot on a pulley that isn't in itself bad enough to bother with. If there were a similar spot on the belt, maybe it would just skip when the two bad parts coincide. Have you tried replacing the belt?
    PS: Maybe you should throw a link to this into the Engineering section.
     
    Last edited: Oct 14, 2005
  24. Oct 15, 2005 #23

    wolram

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    Thanks Dager, The thing is to stupid for engineering, the belt has been changed
    twice and the pullies are as new.
    and yes we deliberatly put the bar in to stop the sleeve arm moving and the
    belt did not jump the main clutch disengaged.
    One of the guys that has looked at the problem advises companies on drive
    train and power trasmision, he tells us this drive is if any thing over engineered.

    We have had a camera looking at this machine now for over a week and it has
    not picked up any human intervention.
    The next thing we want to do is get a high speed camera to look at just the
    problem area, that will not be easy or cheap.
     
  25. Oct 15, 2005 #24

    Danger

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    Now you've got me completely intrigued. Man, but I wish I could get my mitts on that thing in person.:grumpy:
    As for the high-speed photography, I wonder if a stroboscopic examination first might eliminate the need for it. Just thought of something else too. Could you mount a contact sensor (microswitch, strain gauge, etc.) just outside of the belt's turn radius around the pulley? That could detect the beginning of a jump and trigger your surveillance equipment.
     
  26. Oct 15, 2005 #25

    wolram

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    That idea may save £s, thanks danger.

    Hey i wish you could have the b******* thing i have never in my 25yrs
    of this industry come across some thing so illogical, i was intigued at first
    now i am totaly lost, i have spent approx ten hours on and off watching the thing and it never jumped, if only i could see what happens :grumpy:
     
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