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Re: spin maximizes the Ampere law that makes the Inert Gases Chapt13.4.03 Charge and spin #1023 New Physics #1143 ATOM TOTALITY 5th ed
Posted:
Nov 25, 2012 7:41 AM
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On Nov 25, 6:03 am, "Lord Androcles, Zeroth Earl of Medway" <LordAndroc...@November2012.org> wrote: > "Don Kelly" wrote in messagenews:1ogss.6280$Mm3.1777@newsfe26.iad... > > On 24/11/2012 6:35 PM, Lord Androcles, Zeroth Earl of Medway wrote: > > > > > > > > > "Don Kelly" wrote in messagenews:LGess.24063$Sm5.11551@newsfe25.iad... > > > On 23/11/2012 11:58 PM, Lord Androcles, Zeroth Earl of Medway wrote: > >> "Don Kelly" wrote in messagenews:ExZrs.12238$nO.12034@newsfe29.iad... > > >> On 22/11/2012 7:49 PM, Timothy Sutter wrote: > >>> Don Kelly wrote: > > >>>> Timothy Sutter wrote: > > >>>>> Archimedes Plutonium wrote: > > >>>>>> Timothy Sutter wrote: > > >>>>>>>>> and, it really does seem as if > >>>>>>>>> the little whizzers =DO= -have- "flight paths" > >>>>>>>>> and that they are -not- simply in > >>>>>>>>> 10000000000000000000000000000000000000000 > >>>>>>>>> places at the same time.... > > >>>>>>>> just look at these images... > >>>>>>>>http://en.wikipedia.org/wiki/File:Various_Spirograph_Designs.jpg > >>>>>>>> see, you don't just see the cloud of uncertainty > >>>>>>>> you see distinctly flight paths... > > >>>>>>> the thing about the spirograph images is that they are =flat= > > >>>>>>> and the atom travails in -volume- and so, 3D images > >>>>>>> and you really would wonder if the shapes of snowflakes -are- > >>>>>>> sort of like the shapes of certain electronic flight paths... > >>>>>>> "but isn't i true that no two snowflakes are alike?" > >>>>>>> have you really looked at all of them? > > >>>>>>> STOP > > >>>>>> Hi Tim, I will stop for 3d volume. > > >>>>>> It has been a long time since I took apart an electric motor of its > >>>>>> windings of copper wire. > > >>>>>> Tell me, are the windings close to being spherical in all? And are > >>>>>> the > >>>>>> windings of 1 long copper wire or are they of 2 long copper wires or > >>>>>> more? > > >>>>> i just happen to have the motor of > >>>>> an olde box window fan in the basement. > > >>>>> it's a lot of copper wire and these things called > >>>>> "bushings" that seem to be copper as well. > > >>>>> it doesn't look too much like this one > >>>>> but it resembles it a little bit. > > >>>> The box fan motor is likely a single phase shaded pole induction motor. > >>>> Such a motor will have no commutator as shown in your permanent magnet > >>>> DC motor (it also will not have permanent magnets and the rotor will be > >>>> quite different in general). > > >>> i'm pretty sure i said they didn't look too much alike > >>> but had a little bit of similarity, and, i still say that now. > > >>> my new fan has a fairly small motor with a diameter > >>> of about 5 inches and no exposed copper, but my > >>> old fan motor was larger and you could see blobs > >>> of copper wiring -somewhat- like that scooter motor. > >> Your new fan, considering its size may be a "brushless DC" motor - it > >> too will have coils. > > >>> just seeing the copper coils is a similarity. > >> Yes- there is a similarity- the same as the similarity to a solenoid and > >> a transformer. seeing copper coils in a transformer > > >>>> The "bushings" are "oilite (sic?)" bearings which are > >>>> typically copper or a copper alloy which is sintered and holds oil. > > >>> my old fan may have had this little felt tipped > >>> front end where you had to oil every so often. > >> That figures. > > >>>> They are cheaper than ball bearings but don't generally last as > >>>> well.. However, these bushings have nothing to do with the > >>>> electrical/magnetic operation of the motor. > > >>> it's possible that these old bushings were carbon > >>> and would crud up after a while and you'd have > >>> to clean up the crud. > >> Doubtful. However graphite has been used as a lubricant. Sintered bronze > >> is common. > > >>> maybe i'll dig it out and take it apart unless > >>> i already disposed of it in an enVIromentally safe manner. > > >>>> As for Archie's question- No- the windings are not spherical at all. > > >>> no, many coils are sort of round or cylindrical and not spheres. > >>> i have an olde starter motor that may be a -little- bit more > >>> like the scooter motor, but i'm, not in the mood to take > >>> it apart right now, as, it is greasy and secure where > >>> it is on its little shelf. > >> Cylindrical is common and practical."sort of round" is meaningless. > > >>>> As usual he is off in his own little world -where facts are not > >>>> important. > > >>> well, yon Pluto does -ask- if the windings are spherical > >>> Pluto doesn't exactly tell me what sort of motor > >>> i have and then tell me how it's constructed. > >> If I am wrong- let me know. > >> Fan- typically 120V (240V in UK) -assumed not to be a new fan (you said > >> old(e)) so what is typical? A form of small induction motor-with coils > >> on the stator. If it is a DC motor, then the construction will be > >> essentially the same as the scooter motor with coils on the rotor and a > >> commutator. The presence of a commutator is a give-away. > > >> -----rant snipped------ > > >> ====================================================== > >> If DC then even 30 years old it'll be brushless, floppy drives have come > >> and gone long ago, Don. > >>http://en.wikipedia.org/wiki/File:Floppy_drive_spindle_motor_open.jpg > >> The fan on my computer is variable speed, it speeds up if the processor > >> gets hot and slows to reduce noise. > >> It's difficult to imagine any young engineer designing a commutator in > >> 2012 or any entrepreneur investing in one when it can be made on a chip. > >> I have a TV on a dongle and if you want power just look at the microwave > >> oven, it's a low to high frequency converter at over one horsepower. > > >> -- This message is brought to you from the keyboard of > >> Lord Androcles, Zeroth Earl of Medway > > > I think that we may be involved in a case of terminology. > > To me, a box fan is a fan, run from a 60Hz 120/240V system or a 50Hz > > 240V system, which is in a square enclosure and is used for room > > cooling. Many are portable and will have shaded pole induction motors > > and have some speed control (3 settings typically) which may simply be > > switching steps on an autotransformer or by control of a triac. These > > are cheap and reliable- although bearings can be a problem. This is what > > I assumed that he was looking at and trying to compare to a commutator > > motor. > > > I would use "case fan" for the ones used in a computer and, yes, these > > are 'brushless DC' with electronic commutation of what is essentially an > > AC synchronous machine or a stepper. My comments did not refer to these > > but the resemblance that was mentioned is only that all have windings. > > > As to the conventional commutator machine- these are still in use and > > are dying out as better power electronic switching makes it possible to > > eliminate the mechanical commutator which limits the practical upper > > size of DC machines and is a major maintenance problem. > > I do note that they are still in use in many applications -e.g. the > > series DC motor used as a car starter- where the inherent behaviour is > > preferable. > > I also note that large inverter drives supply AC machines- mostly > > induction machines. > > > I am also quite prepared to say that I don't actually know what kind of > > fan and wha was its use -so that I just referred to what I call a "box > > fan" as above. > > ==================================================== > > Ok, we are almost completely in agreement. > > I've never come across a triac or autotransformer controlled induction > > motor though. That would be like trying to control a fluorescent lamp. > > Multi-speed ceiling fans with induction motors have two windings, > > one of which can be switch configured as a 4-pole or 8-pole (2-pole > > is much too fast for a ceiling fan) and the other a 12-pole in a > > 24-slot stator. > > That is true for ceiling fans but there are some room fans with speed > control for which there is no coil switching. I had one which I had to > take apart to get at the bushings and soak them in oil -got an extra > year out of it- and it is definitely a shaded pole motor with no coil > switching. I didn't take apart the control section in the stand but I > would expect something involving a small autotransformer with taps or a > triac. I have a small blower in a fireplace that has a similar motor and > I installed a triac dimmer rated for motor loads and this works well. I > can set a lower voltage limit so that it won't stall. An exhaust fan > over the stove is similar. I expect that the R/X ratio of the motor is > such that the peak torque is near standstill. > > ====================================================== > Triacs should only be used when the load is resistive. > At standstill (say you lock the shaft of a squirrel cage induction motor) > one can view the stator as the primary of a transformer and the rotor > as the secondary with a shorted turn. That is max torque. As the rotor > accelerates the difference between the rotor RPM and field RPM of the > stator (known as the slip frequency) gradually reduces to zero at > synchronous speed and the torque vanishes, the motor is then just > an inductive load like a transformer with no load on the secondary. > I can't imagine why anyone would want a variable speed fan in a > stove hood. > > > What has really made today's speed control possible is permanent > > magnet technology with modern alloys. No need for the old Ward > > Leonard system, some still used on old elevators. > > Permanent magnets do simply replace the old wound fields in the > motors-but the real speed control is due to the inverters providing > variable frequency to (typically) induction motors which do not have > magnets. > ===================================================== > I do not agree. An induction motor without a permanent magnet cannot > be synchronous, it has to slip and the slip is load dependent. That's not > speed control. > > The brushless DC motors are essentially permanent magnet > machines with switched poles and are inherently AC ... > > read more »
Imperial motors run on AC and DC. Electic motor is push and pull?. The "linear induction motor gets pulled in a staight line. TeBet
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