If this is your first visit, be sure to
check out the FAQ by clicking the
link above. You may have to register
before you can post: click the register link above to proceed. To start viewing messages,
select the forum that you want to visit from the selection below.
This picture was found online from 1949 Navy training manual on magnetism, and it shows the "ramp" (soft iron) to have south pole (inflowing) on bottom end and north pole (outflow) on top end, closest edge to magnet....and little/no fields on the side. Is this a correct representation of the polarities of a ramp next to a South facing Stator magnet? The earlier posts have me a little confused on this issue of induction. I also understand that the ramps induction could change with the influence of a close passing rotor magnet but trying to grasp just the stator and ramp.
Kent
That image is completely wrong.
First they are showing a full North to South flow...which never takes place like that...those are iron filings based theories, and that is wrong method to "see" magnets...and believe me...all this kind of images will do is confuse you even more...to a point you will never understand what would develop here very soon.
Where is the Domain Wall, Bloch Wall and low pressure flow from center of magnet towards both poles?...
Principles for the Development of a Complete Mind: Study the science of art. Study the art of science. Develop your senses- especially learn how to see. Realize that everything connects to everything else.― Leonardo da Vinci
On a 12" diameter circle the circumference is 37.7" and this divided by 8 (magnet ever 45 degrees) equals 4.71", the curved distance between magnets. He describes the rotor length at 30 degrees (37.7 / 12) would equal 3.14".
mkt,
Is there a typo above in the underlined word rotor and you meant ramp...correct?
...so as a rotor magnet passes a stator magnet you need a space before the beginning of the next ramp. The distance of this space varies with magnet strengths but a rule of thumb is a minimum of 1.5 to 2 times the gap between the rotor magnet and the ramp, at its widest point. In my 8 pole motor, with magnets every 45 degrees, the ramp length was about 30 degrees. Yours may be a little different.
I do not quite understand this length measurement in degrees so calculated this to see what the possibilities were. If you look at this as a ramp coming off the 0 degree mark (pointed toward 45 degrees) then its length would be about 3.14", less 1/2 the width of the magnet if it touched the side. If you look at this as a ramp coming from the 45 degree mark pointing back toward the 0 degree then this ramp length could be (4.71" - 3.14") 1.57".
Anyone else looked at this?
Kent
I believe everyone here has gone through this Mack's paragraph a few times...plus the whole thing prior as well.
I see no problem with your calculations above...meaning, I know what you are doing...but you express it wrong.
The length of Mack's Ramp is 3.14" that is 30º...and the space between end of ramp to next rotor magnet (center) is 15º which is exactly as you wrote 1.57" circumference...but that is NOT the ramp length, but the space between "end of stator-beginning of next ramp" as Mack refers on above (complete) paragraph in red.
So if you calculated this space already (1.57"=15º)...He writes what I have in red above:
(Space calculation): a rule of thumb is a minimum of 1.5 to 2 times the gap between the rotor magnet and the ramp, at its widest point
If we have "the space" then the gap between rotor magnet and ramp at its widest point is 1.57" divided by either 1.5 or 2 as minimum distance. From here we can know approximately the ramp curvature...couldn't we?
But this could not be that simple...I believe the ramps not necessarily follow a perfect circumference along rotation line...to then "smoothly bend over to a perfect calculated gap...life would be too good always...but, unfortunately it is not like that...
One last thing. Start thinking in three dimensions and give the “transition point” between the ramp and magnet some thought.
Mack
So, if we are just considering x,y diagrams so far to render ramps (2D)...stop, and think 3D...or using the vertical or z axis...and all kind of curves that could generate between all three of their planes ...
Ufopolitics
Principles for the Development of a Complete Mind: Study the science of art. Study the art of science. Develop your senses- especially learn how to see. Realize that everything connects to everything else.― Leonardo da Vinci
Mira, para un sistema basado en cuatro polos (4 para rotor y 4 para estator) necesitas rampas de aceleración mucho mas largas. Imagina que Mack en sus ocho (8) polos, queriendo decir que su espacio entre imanes es de 45º las rampas toman 30º.
Si tú tienes espacios de 90º entonces tus rampas debiesen medir aproximadamente 60º, dejando un espacio de 30 entre el final de la rampa y el próximo imán estator.
otra cosa, necesitas tomar inducción magnética del estator próximo a la rampa, queriendo decir que debes estar muy cerca o tocarlo si es posible.
Te aconsejo que uses ambas rampas opuestas simultáneamente.
Pero para hacer esto necesitas fijar las rampas y sólo moverlas suavemente al unísono.
y necesitas sujetar la cámara...asi que mira a ver. como lo haces.
Saludos
Ufopolitics
Principles for the Development of a Complete Mind: Study the science of art. Study the art of science. Develop your senses- especially learn how to see. Realize that everything connects to everything else.― Leonardo da Vinci
UFO,
Correct on the typo, it should read "ramp length" and I agree that it is not the actual length but rather a point where the ramp comes to. Just trying to effectively use the info given.
Also, thanks for your comment on magnetic flow diagram.
Kent
In all my trials I have discovered what I think is the ideal shape for the ramp. I call it a butterfly pattern. Observe the shape of a butterflies wings. I have also found it is easier to use both wing shapes, one on top, one on bottom to easily balance the rotor. Good Luck. stealth
Great pointer Stealth that pattern is like UFO's Ramps.
Tonight I used a weak/cheap compass to look at the magnetic field of simulated ramp. I used 4 "long" (.5x.5x1) magnets joined end to end for simulated stator magnet and the 12" steel shaft as ramp. I learned a lot from watching the compass needle as I moved it around the ramp. I had the ramp about 1"-2" from south end of magnet, at an angle. (And later touching the side) As the compass traveled in pattern similar to rotor magnet it pointed to end of shaft then straight toward side of shaft until about 2/3rds down shaft then it pointed toward the stator magnet end.
It was easy to see the magnetic field with the compass and it was similar to the drawing I posted but, as stated by UFOpolitics, there was not a change of the magnetic pole at the end of the shaft near the magnet. Polarity stayed the same. The ramp bent the field on the entrance side and left the exit side of magnet as it was. The field at the entrance end of shaft did seem stronger than the field along shaft's side as I moved compass down (parallel to) the shaft.
I realize the rotor magnet will also induce the ramp but I wanted to see the base field first.
Kent
After many years experimenting''''''''''''''''''''''''''''''''''''' '''''''''''''''''''''''''''''''''''''''''''''''
I call it a butterfly pattern. Observe the shape of a butterflies wings. I have also found it is easier to use both wing shapes, one on top, one on bottom to easily balance the rotor. Good Luck. stealth
LIKE THIS STEALTH???? Correct this diagram please.
Mira, para un sistema basado en cuatro polos (4 para rotor y 4 para estator) necesitas rampas de aceleración mucho mas largas. Imagina que Mack en sus ocho (8) polos, queriendo decir que su espacio entre imanes es de 45º las rampas toman 30º.
Si tú tienes espacios de 90º entonces tus rampas debiesen medir aproximadamente 60º, dejando un espacio de 30 entre el final de la rampa y el próximo imán estator.
otra cosa, necesitas tomar inducción magnética del estator próximo a la rampa, queriendo decir que debes estar muy cerca o tocarlo si es posible.
Te aconsejo que uses ambas rampas opuestas simultáneamente.
Pero para hacer esto necesitas fijar las rampas y sólo moverlas suavemente al unísono.
y necesitas sujetar la cámara...asi que mira a ver. como lo haces.
Saludos
Ufopolitics
Ufo gracias. Si este motor va a tener exito, esto sera debido a ti. Propongo personalmente a los demas, la version de 4 polos. Es la forma mas sencilla que se puede llamar motor y que permite un ajuste bastante bueno para lograr el balanceo.Es mi opinion. Desde ahi , una vez conseguido,ya se puede pensar en añadir mas polos.De todos modos yo voy a construir un rotor de mayor diametro, porque noto una insuficiencia en hacer las pruebas con el. Si me recordó bien, MadMack recomienda construir un rotor amplio.
Atentamente. cristian
Comment