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  • #31
    Superconductors are magnetic "shields"

    A superconductor does not allow magnetic fields to penetrate it, and can be used to shield something from a magnetic field. I built a drive coupling for a prototype hermetically sealed cryogenic device that used that property to transfer torque. It consisted of a "high temperature" superconducting cylinder with 2 axial slots in it as the driven half, and a 2 pole SmCo magnet inside as the driving half. The magnetic field was "pinched" into the slots when the superconductor was cooled below its critical temperature, and remained "pinned" as long as a subcritical temperature was maintained. One problem is that superconductors have a critical flux density they can withstand for a given temperature, and if exceeded, they go "normal" or resistive, and also lose their magnetic properties. The superconductor we used was in the Yt Ba Cu Oxide family and is usually superconducting at liquid nitrogen temperatures (-320؛ F), but the high flux from the magnet meant we had to cool it down to almost liquid hydrogen (-423؛ F) temps to make it work. This was about 20 years ago, and I understand that high temperature superconductors have much higher critical fields now, so ymmv.
    Davis

    "Nothing is impossible for the man who doesn't have to do it himself"

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    • #32
      Originally posted by dp
      Mu-metal is a pretty decent magnetic shielding material. It is used by disk drives to keep their very powerful magnets from destroying the data on the disks.

      http://en.wikipedia.org/wiki/Mu-metal

      Yes but like I stated - its greatly attracted to magnetism in the process,

      The fact of the matter is is "we" cant achieve the results with what we know, and since what we know is also a part of "what we have to work with" it means that the final answer has to be "we dont know" Why? because what we have to work with keeps changing.

      This is important because its neither a statement of "we cant" which is incorrect for "what we know" (when we become aware that we dont know everything) --- its also not stating "we can" as we already would have because then it would fall into the category of "what we really do know"

      We dont know -- OR "maybe" is the correct answer -- and if one believes differently (Like Evan) that its impossible to achieve then he's acting like "he knows" whats out there,
      The burden of proof lies not on the person who states it could be a possibility due to the fact that they dont know all the elements that are out there - for they realize they are still finding new ones on our own planet

      The burden of proof Does lie on the person who claims to know what all the other elements "we" havent discovered yet in the universe are (which is a contradiction of terms), or that in some way there are no more to be discovered -- good luck with either as thats an impossibility.

      The pyramid of knowledge is a shapeshifter - and can take a few knocks here and there, but there are things that can upset one of the base blocks, when this happens all the others have to be ripped down and re-stacked accordingly
      If you think all the base blocks that we know today will stay where they are for eternity you'd be in for a nice surprise if you could exist long enough...
      All you have to do to verify this is take a few steps back into history...

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      • #33
        Originally posted by interrupted_cut
        A superconductor does not allow magnetic fields to penetrate it, and can be used to shield something from a magnetic field. I built a drive coupling for a prototype hermetically sealed cryogenic device that used that property to transfer torque. It consisted of a "high temperature" superconducting cylinder with 2 axial slots in it as the driven half, and a 2 pole SmCo magnet inside as the driving half. The magnetic field was "pinched" into the slots when the superconductor was cooled below its critical temperature, and remained "pinned" as long as a subcritical temperature was maintained. One problem is that superconductors have a critical flux density they can withstand for a given temperature, and if exceeded, they go "normal" or resistive, and also lose their magnetic properties. The superconductor we used was in the Yt Ba Cu Oxide family and is usually superconducting at liquid nitrogen temperatures (-320؛ F), but the high flux from the magnet meant we had to cool it down to almost liquid hydrogen (-423؛ F) temps to make it work. This was about 20 years ago, and I understand that high temperature superconductors have much higher critical fields now, so ymmv.

        Your very advanced in the "field" (no pun intended) But -- even if you get a superconductor to go (I forget the word for it) "zero resistance" in its operating -- You still have to excite it and then discharge it to shield the magnet - Although near perfect efficiencies can be achieved in the transfer you still have to come up with the energies to do this - right?

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        • #34
          Originally posted by A.K. Boomer
          Yes but like I stated - its greatly attracted to magnetism in the process,
          I was responding to another post, but to get to yours, I'm not aware of any material that shields magnetic fields completely. Any material that is used as a shield and which can be induced to generate it's own magnetic field from eddie currents will be attracted to a magnet and as such is not a candidate.

          Philosophically speaking, it isn't accurate to suggest that given sufficient unobtanium one can create perpetual motion and for the exact reason you suggest - the knowledge is lacking so we can't know that we can. But we can certainly try.

          As for true perpetual motion itself, I cannot think of any practical use for it nor any way to detect it, but that's not to say I can't learn if the knowledge exists even if my brain is full of plaque as you seem to think.

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          • #35
            Originally posted by aboard_epsilon
            if you replaced those magnets with electro magnets in the perpex tubes ..could you say the same then?

            all the best.markj
            The electromagnets require a continuous input of energy to keep them up. This is because of the different way they work....... don't get excited at the difference between "permanent" and "electro" magnets.
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            As for that perfectly shielding but non-magnetic material.......

            I am pretty sure that ANY material, no matter how"unobtanium" it is, that shields against a magnetic field, will require energy to push it into place..... and that (if nothing else) will provide the losses that destroy perpetual motion.

            The magnetic field around any magnet automatically assumes its lowest energy state, given the nature of the surroundings.

            if you put in a ferromagnetic material, that essentially 'shorts" the magneto motive force, and the field is distorted to make all points on the ferromagnetic material have the same "magnetic potential".

            if you were to move a material that simply is not penetrated by magnetic lines of force, you would have to distort the field so that those lines of force go AROUND the volume occupied by the material.

            Since the field was already in its lowest possible energy shape, distorting it will require energy to allow the field to assume its new shape. Somewhat similar to pushing a piece of wood further into water than the depth it wants to float..... that takes energy.

            Therefore, the material, despite its non-interactive nature, if it won't allow the field to pass through it, it MUST require energy to push it into a magnetic field.

            If that is NOT the case, then either it ALLOWS the field to pass through it, OR it is magnetic in some way and acts like a ferrous material.
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            here's another good one for you to ponder....... is the inductance of an air-core coil affected if you put a magnet in the core area? if so, how? Remember, a magnet is an iron-like material, i.e. ferromagnetic.

            What if you put a piece of steel, or iron, ferrite, etc in there?
            1601

            Keep eye on ball.
            Hashim Khan

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            • #36
              Originally posted by dp

              Philosophically speaking, it isn't accurate to suggest that given sufficient unobtanium one can create perpetual motion and for the exact reason you suggest - the knowledge is lacking so we can't know that we can. But we can certainly try.

              It sounds as if your comfortable with the word "maybe" too.

              I didnt mean to "horn in" on your post but I wanted to clarify for aboard_E.

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              • #37
                To understand the electromagnetic force one must be able to understand the mathematics that describe it. I don't understand Maxwell's equations, math has always been my weakest subject. It is those equations that Einstein drew on to forumulate his first paper on the photoelectric effect of light and from there to the theories of special and general relativity.

                A superconductor does not allow magnetic fields to penetrate it, and can be used to shield something from a magnetic field.
                Unfortunately that effect is imperfect since materials are imperfect. Look up flux pinning to see why.

                The fact is is we dont really have a good grasp on just what magnetism really is -- to say there isnt a material in the entire universe that can shield it without itself getting involved is not only arrogant its ignorant...
                We do so know what magnetism is. You don't but that doesn't mean others do not. You continue to trip yourself up with your ignorance of basic science.

                We dont know -- OR "maybe" is the correct answer -- and if one believes differently (Like Evan) that its impossible to achieve then he's acting like "he knows" whats out there,
                The burden of proof lies not on the person who states it could be a possibility due to the fact that they dont know all the elements that are out there - for they realize they are still finding new ones on our own planet
                Nobody is finding new elements on this planet or any other. The only "new elements" are artificial and unstable combinations of subatomic particles that can only exist for very short periods of time created by smashing particles together at high velocities. The only time such events occur in nature is in highly energetic events such as a supernova.

                The burden of proof lies on you to disprove the existing proofs of the electromagnetic effect. To do that you will need to use the same tools that the existing proofs use, higher mathematics. Without those tools you cannot make even an informed guess about the existence of possibilities outside of what we already have discovered and verified.
                Last edited by Evan; 02-08-2009, 09:51 PM.
                Free software for calculating bolt circles and similar: Click Here

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                • #38
                  Originally posted by Evan

                  Unfortunately that effect is imperfect since materials are imperfect. Look up flux pinning to see why.
                  it wouldn't matter..... see the argument above which purports to show that even a perfect shield would not be able to move through a field with no energy consequences.
                  1601

                  Keep eye on ball.
                  Hashim Khan

                  Comment


                  • #39
                    Free Energy is a religion. Its followers rely on faith alone in the absence of evidence. These people think they are the only ones that truly understand science and that they are the ones who will make a breakthrough. Just like the hydrogen generator, HHO guys. People in general like to think they are smarter than the rest.

                    You have about as much chance of getting the pope to convert to islam as you do getting one of these guys to understand it wont work.

                    There are no vast conspiracies, no coverups, none of it.

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                    • #40
                      Originally posted by Evan

                      Nobody is finding new elements on this planet or any other. The only "new elements" are artificial and unstable combinations of subatomic particles that can only exist for very short periods of time created by smashing particles together at high velocities. The only time such events occur in nature is in highly energetic events such as a supernova.

                      .
                      I beg to differ, while this is not the most recent its still compelling --- http://www.jumbojoke.com/new_element...shcronium.html

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                      • #41
                        Originally posted by Evan

                        The burden of proof lies on you to disprove the existing proofs of the electromagnetic effect. To do that you will need to use the same tools that the existing proofs use, higher mathematics. Without those tools you cannot make even an informed guess about the existence of possibilities outside of what we already have discovered and verified.


                        Evan Once again you totally miss the point and contort yourself into a total hillbilly ---------- there is zero burden of proof on me -- Im not the stooge who made an absolute statement --YOU ARE,
                        furthermore -- if you were paying attention it would be impossible for me to disprove anything as that would require that I take the existing proofs to be here and now and for eternity ------- ONE more time -- existing proofs are just that -- they are timeframed and subject to change and WILL -- in what direction I have no Idea as neither do you no matter what you claim to know. But one thing for certain is you cook your own goose in making an absolute statement -- esp. one that claims of the impossibility -- now your trapped --- Time is infinite.

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                        • #42
                          Evan Once again you totally miss the point and contort yourself into a total hillbilly ---------- there is zero burden of proof on me -- Im not the stooge who made an absolute statement --YOU ARE,
                          Mathematics is very interesting. It is the only area of human endeavour where perfection may be found. It can be as simple as 2 plus 2 equals 4. Mathematics if filled with examples of absolute statements. In the discipline of logic these are called tautologies, a statement that is automatically and by default true. A=A is such a statement.

                          In Real Life there are many such examples of absolutes as well. You cannot fly by standing on the ground and flapping your arms. Why? The answer lies in the mathematics that describe the situation. We may calculate how much lift you are capable of producing by flapping your arms and then compare that to the amount it would require to lift your body against the force of gravity.

                          The mathematics will show that there is absolutely no way that you can generate enough lift to fly by flapping your arms. To disprove that you will need to point to an error in the mathematics and explain why it is wrong.

                          The same applies to some of your statements regarding what is possible with electromagnetics. I understand enough of the math to know that the math is correct.

                          What you don't understand is that the idea of there always being additional possibilities as yet undiscovered is absurd. The universe is governed by limits. Those limits are often absolute and do not admit of any exceptions. If you wish to posit an exception then you are making an exceptional claim. Exceptional claims require exceptional proof. The burden of proof rests on you.
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                          • #43
                            No one seems to have pointed out that in the video which started the thread work was done to accelarate the motor from standstill, it has a lever which was actuated to start things up!
                            Nick

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                            • #44
                              Originally posted by NickH
                              No one seems to have pointed out that in the video which started the thread work was done to accelarate the motor from standstill, it has a lever which was actuated to start things up!
                              Nick
                              That is the way that it looks BUT they don't show the output shaft in the video until AFTER they start to power down.
                              To invent, you need a good imagination - and a pile of junk. Thomas A. Edison

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                              • #45
                                Originally posted by Evan
                                ... I understand enough of the math to know that the math is correct.

                                What you don't understand is that the idea of there always being additional possibilities as yet undiscovered is absurd. ...
                                Mathematics is a way to formalize what we already know. You can't often predict the new from the mathematics of the old. When a totally new physical concept is found, the mathematics to describe it gets developed. Aristotle didn't have differential calculus to predict gravity and orbital mechanics. It took 2000 years for Newton to develop calculus to facilitate his description of gravity. Complex variables and tensors electromagnetics went hand-in-hand. The math behind quantum physics didn't really exist much before Schroedinger. Einstein proved the math describing classical mechanics was wrong. A good approximation in it's context, but wrong in a domain beyond our senses' direct physical observations.

                                All mathematics is "wrong" because it is a reflection of our perceptions which are not all-knowing. Just because a concept isn't reflected in the existing math doesn't mean it's wrong. However... yes, you do need to somehow provide proof that the currently accepted laws of thermodynamics are incorrect for me to believe it. After that, somebody will change mathematics to reflect the fact.

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