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Topic: 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
Replies: 15   Last Post: Nov 27, 2012 5:25 PM

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herbert glazier

Posts: 192
Registered: 7/26/10
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



Date Subject Author
11/25/12
Read 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
Lord Androcles, Zeroth Earl of Medway
11/25/12
Read 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
Jos Bergervoet
11/25/12
Read 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
Lord Androcles, Zeroth Earl of Medway
11/25/12
Read 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
Jos Bergervoet
11/25/12
Read 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
Lord Androcles, Zeroth Earl of Medway
11/25/12
Read 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
Jos Bergervoet
11/25/12
Read 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
Lord Androcles, Zeroth Earl of Medway
11/26/12
Read 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
Jos Bergervoet
11/25/12
Read 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
herbert glazier
11/25/12
Read Re: motor control
--
11/25/12
Read Re: motor control
Lord Androcles, Zeroth Earl of Medway
11/26/12
Read Re: motor control
--
11/26/12
Read Re: motor control
Lord Androcles, Zeroth Earl of Medway
11/27/12
Read Re: motor control
--
11/27/12
Read Re: motor control
Lord Androcles, Zeroth Earl of Medway
11/25/12
Read 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
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