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A simple problem

  1. Mar 25, 2006 #1

    wolram

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    I am no fan of doing away with human labour, but needs must, an (opperator) has to place a circular sponge into a pot that has all ready
    had two very viscuous substances, automatically depossited into it, the sponge has to be placed level in the pot, which could mean that the (opperator) has to push it down on one side or the other, if one considers
    that theese sponges are baked and not very symetrical and are crumbly by
    nature, could any one come up with some automation that will replace the
    opperator, i have all ready said no, unless a very substancial budget is
    assigned the project, we have all ready trialed three inventions by the origonal machine manufacturer with very poor results,
    I do not want you to invent any thing, just give your thoughts on the
    praticle side.
     
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  3. Mar 26, 2006 #2

    brewnog

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    The two viscous substances, let's call them cream and jam. Are they already mixed? Are they in layers?

    What would happen if you just pushed down on the whole sponge with a big plate, surely this would cause the sponge to self-level?

    Obviously pretty simple, I'm just trying to work out what I've missed.
     
  4. Mar 29, 2006 #3

    Danger

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    Sorry; I lost track of this thread before I had a chance to respond. It seems like a reasonably simple task, so there must indeed be some information missing that complicates it. What sort of scale are we dealing with here? Cooking pot size, or huge industrial cauldron or what?
     
  5. Apr 9, 2006 #4

    wolram

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    The sponges are about 2 inches dia, and come in cellophane tubes, 50 per
    tube, problem 1 is they tend to stick to gether, problem 2 is they are not a
    regular shape just roundish, problem 3 is that any mechanism has to fit within the confines of the machine which means some sort of vertical magazine, which has to hold at least 5mins worth of production @ 300 min
    the sponges are about 3/16 to 1/4 thick and can be slightly concave or convex.
    the machine is 4 foot across and has 4 (lanes), the pots have jelly first then
    custard then sponge then cream, the biggest problem is the fragillity of
    the sponges, if they are held in vertical mag 25 is about the max befor what
    ever machanism starts chewing them up.
    there is 8ft head room over machine and 6ft of track free for this opperation.
    some sort of overhead feed conveyor is an opption, but one opperator has to feed the machine with pots, lids and sponges. :smile:
     
  6. Apr 9, 2006 #5

    Astronuc

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    I see sponge separation as a critical problem if they are "stuck together" and "fragile/crumbly". Perhaps one could use a gentle air jet, but recognizing the boundary is the key.

    Various industries use circular systems, e.g. bottling industry to fill and cap bottles, and the pharmaceutical and nuclear fuel industries use rotary presses to press tablets and pellets respectively.

    Cassets could be used to contain the sponges, but still reliable separation and insertion remain key. Perhaps a head with a gentle vacuum can be used to retrieve the sponge (in conjunction with gentle air jet blowing on the interface between sponges for separation) and hold it in place while inserting it, and the gently 'blow' the sponge into the container.

    God, I can't think of anything more tedious than separating sponges and placing them in small containers just so! :surprised Well, may be I could, but why torture myself? :biggrin:
     
  7. Apr 10, 2006 #6

    wolram

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    The worst job in the factory is spoting, some one has to stand and look for any defects, befor they go on to metal detector, check weigher, i did it for half an hour and nearly fell over when i looked up. the opperators do this in
    4 hr stints :cry:
     
  8. Apr 10, 2006 #7

    Astronuc

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    In-process QC - it's excruciatingly tedious and as you said, spotting is so un-natural - standing there, head down, staring at moving things while not moving. :yuck:
     
  9. Apr 10, 2006 #8

    wolram

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    Astro, we trialed air jets for seperating sponges, eventually building up to an (air knife), all i can say is crumbs :smile: the way the opperators seperate
    them is by a twist, this seems to cause the least damage, but even with
    the best opperators there is 3% average wastage due to broken sponges.
    I did suggest they cut the sponges out a baked sheet for symetry and dust
    them with an anti stick agent, but i was given a million reasons why this is
    not practical ? i did hear that a mark 4 is on the drawing board, i bet a pound to a penny it will end up in the, it may be useful pile.:smile:
     
  10. Apr 10, 2006 #9

    Danger

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    I didn't realize that you were talking about sponge cakes. That does make a difference. What would the odds be that you can freeze them, cut them apart, and then thaw them again?
     
  11. Apr 10, 2006 #10

    wolram

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    Hi Danger.
    The big problem with that is keeping them frozen, we have to do this with fruit we have a freezer near by that gets down to minus 40 but in practise
    with constant door opening it is minus 20, the room is kept at 10c, this gives us about 30 mins handling time befror they start to thaw out, when the opperators go for a half hour break the fruit can go back in the freezer as it is kept in trays, i am not sure how we could do that with sponges, and what
    sort of problems we would have if they did start to thaw out.
     
  12. Apr 10, 2006 #11

    Danger

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    In that case, what about getting the blokes who make the sponges to insert wax paper or similar between them before stacking them up? That's how frozen hamburger patties are done here, and it works well.
     
  13. Apr 10, 2006 #12

    wolram

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    That is a good idea, although i have no idea how they package these things,
    i will ask questions, in the mean time have you worked out how to get them in pots :smile:
     
  14. Apr 11, 2006 #13

    FredGarvin

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    Sorry Wolram, I haven't had a lot of time to reply to this.

    If I read the thread there appears to be a few "issues" at hand:

    - Cutting the sponge cakes
    - Placing the sponge cakes
    - Making sure they are even

    Is that the gist?

    The first thing I think of when cutting like this is a heated element like a wire cheese slicer. I am trying to think if the heat would buy you any advantage in keeping the cake from crumbling...

    The next thing I was throwing around was a vacuum that could pick up the cake and place it. As long as the vacuum is distributed over the entire surface, Id on't think you'd have breakage issues. The part that holds the cake could put a very slight pressure down on the cake once it's in place and releases the vacuum and that way it should be leveled the same way every time.
     
  15. Apr 11, 2006 #14

    wolram

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    Hi Fred, the biggest problem, (i think) is presenting a single sponge to what
    ever deposits it, we need to store about 400 per lane to give a minimum
    of 5 mins opperation per load, and an opperator has to be able to quickly refill the storage, this one opperator has to keep the machine fed with pots lids and sponges, then there is size restrictions, 4ft width, 6ft length 8 ft
    hight.
     
  16. Apr 11, 2006 #15

    Danger

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    I don't suppose that they'd alter the sponge recipe to make them less crumbly... :rolleyes:
    Something is just coming to mind as I'm typing, so you're getting it at the same time that I am. If these cakes could be batch loaded (one cellophane tube at a time, on top of each other, with the cellophane removed) into an ever-so-slightly too-small tube (big enough for a stack, then tapered down), a piston of some sort could force them through into the path of a rotating slicer. The compression from the tube might prevent crumbling, at least on the leading edge of the one still inside. With small enough clearance (say maybe 1/2 mm) between the blade and the pot, the cake will be automatically levelled when cut. I think... hmmm...

    Any chance of you posting a wee diagram or something so we know how the various components are related, and how the pots move along?
     
    Last edited: Apr 11, 2006
  17. Apr 11, 2006 #16

    brewnog

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    You're not at the Kipling factory are you, perchance?
     
  18. Apr 11, 2006 #17

    Ivan Seeking

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    The problem that I hear is that you ask for two incompatible results: Cheap and automation. For example, there are vision systems for defect detection but it gets expensive. Frito looks at every single potato chip on a three foot wide conveyor moving at about ten feet a second. If a defect is detected, that particular chip is recycled and checked again. The position of that single chip is tracked and it is rejected after a second pass. So there are always solutions, for a price.
     
    Last edited: Apr 11, 2006
  19. Apr 12, 2006 #18

    wolram

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    You are right Ivan, i have all ready told the powers that be that (their) idea will not be cheap, will take a lot of development, and may be they will not
    recover the cost vs two minimum wage opperators for years, this is why i am
    asking the oppinions of some clever people, gather some ideas and then work
    out some ball park numbers that they can chew on in their endless meetings.
     
  20. Apr 12, 2006 #19

    FredGarvin

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    Question...do they bake the cakes in individual sizes and then package them in the big tube, or it the cake one large cake that is cut?
     
  21. Apr 12, 2006 #20

    BobG

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    It seems to me that you need a constant vacuum sucking the cakes out of the cylinder and that the circumference of the cylinder should vary slightly - this changes the amount of friction holding the cakes in the cylinder. The natural vibration of the machine should weaken the bonds between the individual cakes - and hopefully not weaken the bonds within the individual cakes.

    Edit: Getting a vacuum and a cylinder of varying circumference probably makes the solution too expensive. An open cylinder that's held closed by an electromagnet would probably work better. The current's turned off for a short time when a can passes a switch, allowing the cakes to fall by gravity. The reclosing of the cylinder grabs the next cake in line, and the momentum of the cake, along with the vibration of the cylinder, will hopefully break the bonds between the cakes.

    Tell me about it. One of the minimum wage jobs I had in my younger days was to stand over cans of methanol, peering into them to see if they were filled to the right level and hoping a can didn't misfeed in the capper, resulting in a spray of methanol jetting out of the can I was peering into (the cheap shop safety glasses supposedly protected your eyes, but... ).

    Eventually it dawned on me that I could listen to the cans instead of peering into them. They rattled as they moved down the conveyor and, with a little practice, the low notes of the deficient cans was so obvious that you could pick a single 'low' can out of the chain before you even had to visually check it.

    It always bothered a few of the foremen that I would stand there with my eyes closed, but they found it hard to argue with results.
     
    Last edited: Apr 12, 2006
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