Hi Gang,
You might check out this motor I have been working on for last couple years.
http://youtu.be/9s7sM3csFHM (http://youtu.be/9s7sM3csFHM)
Respectfully,
Ben K4ZEP
Hi Gang,
Tomorrow I will build the Thomas motor using the same configuration as the ORBO, i'll switch back and forth between coils, The Thomas Coil and The ORBO coil and show the difference. They both work but the Thomas is much more efficient... The ORBO requires the same energy to change the permeability of the core as the Thomas, give or take but the Thomas PUSHES with static magnets after TDC., The ORBO only pulls with magnet to core interface. We will ignore the generator action for now. This is just plain fun.
See photo/drawing. Notice the magnet of the ORBO pulls in till TDC, turn on core/shifts the PErm. to Zero, coast on by, hence runs. Thomas same, magnet of the Thomas Pulls in till TDC, the coil turns ON/Perm. drops to 1 give or take, rotor magnet sees core magnet which pushes it away the coil turns off and both cycles continue over and over again.
Ben
Hi ben, thanks for sharing.
Can the rotor magnets be directly across from the toroid, or does it have to be offset?
In the video, it sounded like you said you did that to prevent the high speeds, due to construction setup so far.
You have my interest, as i happened to pick up four good sized ferrite toroids at the surplus shop, few months ago.
Could you explain the benefits of this design, in your own words, if it functions how you think it does.
Though i have an idea of the benefits, rpm is not limited by induced counter emf from magnets and toroid permanent magnet gives a boost out of core area and this boost also avoids to some degree, the drag back (reluctance) to core losses.
May build a small test model myself.
peace love light
tyson :)
Quote from: SkyWatcher123 on March 07, 2014, 01:58:28 AM
Hi ben, thanks for sharing.
Can the rotor magnets be directly across from the toroid, or does it have to be offset?
In the video, it sounded like you said you did that to prevent the high speeds, due to construction setup so far.
You have my interest, as i happened to pick up four good sized ferrite toroids at the surplus shop, few months ago.
Could you explain the benefits of this design, in your own words, if it functions how you think it does.
Though i have an idea of the benefits, rpm is not limited by induced counter emf from magnets and toroid permanent magnet gives a boost out of core area and this boost also avoids to some degree, the drag back (reluctance) to core losses.
May build a small test model myself.
peace love light
tyson :)
Good Morning Tyson,
Just got up, 6:30 am, was up late last night, drinking my Decalf Coffie.
To answer your first question. Can the rotor magnets be directly across from the toroid, or does it have to be offset?
I find that the offset seems to work better, leaving the S side of the offset magnet in the air/open with air having a u of 1, seems to give the best effect if we are going to use N magnets approaching the toroid on the rotor. I don't know exactly why but it definitely does. I tried magnets all the way across the toroid and it did not work at all. I think I know but will let it go till later.
In my first video, the side loading on the rotor magnets by the toroid caused harmonic loading and unloading of the rotor due to it not being rigid enough. In the second video I mostly get rid of that problem except bearing tolerances.
Benefits: You pretty well much answered you own question. Correctly set up, the small BACK EMF, GENERATOR EFFECT adds to the thrust due to the direction of the induced field in masking/switching/changing the toroids permeability. See two pictures attached, First one is motor pulse, second one is generator pulse with motor pulse off, they are additive. The coil doesn't care about polarity to change the u so it could be either way and work the same. Remember without the coil, the magnet is pulled into the core and then after TDC it is pulled back towards the core, hence canceling out any benefits. By changing the permeability, we can make this action non linear or be used as a motor action. When we lower the permeability of the toroid, the repulsive magnet on the inside (or opposite side from the rotor through the toroid core) is now seen by the rotor and you have additional kick. This additional kick is one of the main differences between my motor and the ORBO motor. Pulse motors is one of many things I mess with for fun, build one. BE SURE you have a very free bearing to support the rotor and go for it. :) Remember all, this is for fun! I'm a old geezer, do a lot of of stuff from intuition/experience, etc. I quit writing technical papers 10-15 years ago.
Ben
Hey Gang,
Latest video of ORBO style motor or at least a masking type device. I'm totally flummoxed, surprised, etc. Jaw droopping, cant believe my eyes.
This damn thing is faster than my "Thomas" motor! >:( I have no idea why it runs so well but run it does. :o Coil is 28' #38 wire on toroid core, same switching,
same rotor, all things being equal, just damn fast. Does not show the generator effect that the Thomas does, that can be good or bad. Anyway. Good Bad or UGLY,
here it is!
http://youtu.be/aCpniBm9i_M (http://youtu.be/aCpniBm9i_M)
Respectfully
Ben K4ZEP
Worlds smallest lab
Dear Ben,
I could not get the mA draw from your previous video, would you tell.
With your saying "all things being equal" it means the current draw is also the same at the same supply voltage?
Thanks, Gyula
Quote from: gyulasun on March 07, 2014, 05:14:35 PM
Dear Ben,
I could not get the mA draw from your previous video, would you tell.
With your saying "all things being equal" it means the current draw is also the same at the same supply voltage?
Thanks, Gyula
Hi Gyula,
Just referring to both coils are about the same, at a given voltage, both versions draw the same current due to same duty cycle from the Hall effect driver at low RPM. The Orbo shielding and coasting by, and my motor where when the shielding occurs and the magnets push should be faster but doesn't appear to, but I need to do some accurate RPM TEST to be sure, I'm really not doing very percision work/testing right now, will refine it as I go along. I can switch either coil in and out of the circuit at will right now to do the speed test.......
Learning curve is steep here! The main difference is that all things being equal, the Thomas motor due to the generator effect draws 5-10% less current at speed than the pure ORBO without a generator. At 4000 rpm, we have about a 2 volt generator pulse being added to the motor pulse, hence the less current.
Respectfully
Ben K4ZEP
Hi TK,
Thanks for the explanation, which I have copied from above YouTube. I must disagree with you on some points.
TK: Thanks... but no, I don't think that is quite how it works. When the coil is on, the entire toroid core becomes saturated: this means its permeability is now 1. So the field from the PM inside the core can now pass through it like air, instead of being "sucked" into the non-saturated toroid.
BT: I agree with you here in that the magnet in my rotor and the ORBO [/font]is sucked into the non-saturated toroid core.
TK: The Orbo in my video has no magnetic field from the coil outside the toroid, and it works by reducing[/i] the ability of the external rotor magnets to attract the toroid material itself, and this is true for both polarities. The electrical pulse to the coil is turned "on" as the magnets pass the core, not before, so that there is a reduction in attraction as the rotor magnets recede from the toroid core. This is what speeds up the rotor.
BT: I think you realize all the speed up has already occurred due to the "sucking in or attraction" of the magnet to the core before you make the core invisible at TDC which then just coast away. Unless the core saturation is perfect, the will be some losses in speed but that is a small point at this time.[/i]
TK: And the polarity of the current and the polarity of the rotor magnets doesn't matter at all. It is neither an attraction nor a repulsion pulse motor, it is a unique third kind, the Core Effect motor.
BT: That is true if you are using EM's in the rotor as the core of the toroid doesn't care as it is attracted by either field and the core of the toroid doesn't generate a field that effects magnets either EM or Permanent.
I'm not sure the ORBO is a third kind of effect, it always appeared to me to be a switched reluctance motor using permanent magnets and switching the cores, hence the torque.
TK: I think you have turned your pure Core Effect motor into a biased attraction or repulsion pulse motor by putting the PM in there. Nothing wrong with that!
BT: True it is a pure attraction motor (rotor magnet to stator core attraction), up to TDC just like the ORBO, BUT due to the core material masking the core magnet, the rotor magnet does not see that hidden core magnet. When you turn on the coil at TDC, you unmask the magnet and in doing so you mask the core at the same time so it does not slow down the rotor (Like the ORBO) but the magnet in repulsion that just showed up then gives a second pulse to the rotor. That is the essence of the Thomas motor and with close measurements is more efficient that the pure ORBO.
TK: [/i]But try it without the PM, and time it so the coil pulse starts at the closest magnet approach, not before. You might be surprised.
BT: I did and was very surprised and flabergasted at the efficiency of the ORBO effect as you can see in my FAST ORBO video. BUT I finally realized after posting that video that the pounding I heard in the rotor is not a power pulses in the ORBO motor but due to the fact that with just one coil, I am unloading the side forces on the rotor, hence the noise.....I initially confused that side unloading with a power pulse that not being the case. Dual coils should fix that problem which I probably will do tomorrow. At theoretical best, the ORBO should be ½ as efficient as the Thomas but nothing is perfect and the masking of core, unmasking of "bias" or stator magnet not being perfect, it would something less. A quick measurement shows about a 30+ increase in efficiency in the Thomas motor vs. the pure ORBO seen in the video.
TK: Believe me, I spent years on this stuff and I have perhaps the only quantitative data on the effect of electrical currents on the magnetic attraction of ferrite toroid cores to external magnets that you will be able to find._
BT: Right on TK, I respect your work in this arena immensely; we both have been pounding magnets for years,
In your case a lot more visible than my work and much better illustrated I might say. ]My hat is off to you for all the work you have done.
Ben
Hi Ben,
Thanks for the answer and one more thing I would be curious to know is that how the input current changes when you try to slow the rotor a little, i.e. apply some mechanical load onto the rotor. I think just a little increase may happen in the current draw.
I think the Thomas setup should certainly give more torque than the Orbo setup due to the extra repel force received after the TDC, using the same conditions for both setups. Some finer details here involve considering core saturation: in the Thomas setup it starts the moment you position the small magnet to the inside of the toroid core, my earlier tests using an L meter clearly showed this when was playing separately with some ferrite toroid cores and magnets attached to it. In the Orbo setup, saturation begins when the magnet(s) start to attract to the core and of course this is true for the Thomas setup too. This saturation can be an advantage in bringing down the input power demand to fully saturate the core, and this may involve choosing the strength of the magnet inside the toroid core wisely. I believe the 'wise' choice means here just balancing the repel force between the rotor magnet at or just after TDC and the inner stator magnet to zero via the thickness of the toroid core, this could be adjusted simply by using fine spacers as sandwiches between toroid core inner wall and the inner magnet.
Thanks for showing this interesting setup.
Gyula
Quote from: gyulasun on March 08, 2014, 01:22:59 PM
Hi Ben,
Thanks for the answer and one more thing I would be curious to know is that how the input current changes when you try to slow the rotor a little, i.e. apply some mechanical load onto the rotor. I think just a little increase may happen in the current draw. In the ORBO, no change in current if ratio of off to on stays the same, in the THOMAS, current increases as you slow it due to less generator effect. At ZERO RPM, Current in both ORBO and THOMAS are the same.
I think the Thomas setup should certainly give more torque than the Orbo setup due to the extra repel force received after the TDC, using the same conditions for both setups.
IT does!
Some finer details here involve considering core saturation: in the Thomas setup it starts the moment you position the small magnet to the inside of the toroid core, my earlier tests using an L meter clearly showed this when was playing separately with some ferrite toroid cores and magnets attached to it.
ABsolutely!
In the Orbo setup, saturation begins when the magnet(s) start to attract to the core and of course this is true for the Thomas setup too.
Yes, more so.
This saturation can be an advantage in bringing down the input power demand to fully saturate the core, and this may involve choosing the strength of the magnet inside the toroid core wisely.
Correct, there are a bunch of variables here that could be optimized that I have not done!
I believe the 'wise' choice means here just balancing the repel force between the rotor magnet at or just after TDC and the inner stator magnet to zero via the thickness of the toroid core, this could be adjusted simply by using fine spacers as sandwiches between toroid core inner wall and the inner magnet.
If you mean when the core magnet is off, you are correct. Core ON, permeability near to "1" as you can get it to allow the field to punch/repulse the rotor magnet after TDC.
You have a good handle on this I believe!!!
Ben
Thanks for showing this interesting setup.
Gyula
A most interesting observation. After peaking the motor with magnets getting it to run up to 5200 rpm at 19+VDC. Questions what happens if we reverse the coils? Most interesting. Changing NOTHING but the wiring to the coils, in reverse polarity, up to 11.6 VDC it will run in reverse, above 11.6 VDC it will run normal direction. As you go away from that 11.6 VDC point and lower, it speeds up more, there is more torque away from that point. Same for going above the 11.6 VDC. Current is very high, about 150 to 160 ma which is to be expected. Out of sheer luck and a lot of experimentation I have found the sweet spot where the fields from the core magnet and the polarity of the field in the core and the field from the rotor all comes together. It is a very dynamic thing. I just realized it should work great with AC as a synchronous motor with magnetic enhancement using 2 magnets side by side, pull in with a S magnet, push out with the N magnet, both enhanced with the polarized field from the windings.. Waiting for parts for the next motor.
Having fun.......
Respectfully
Ben
Hi Ben and Gyula.
You might be interested in a couple more of my Orbette 1.0 vids. In this version of Orbette I used ferrite "beads" which are more like hollow cylinders than toroids, because those were all I could get at the time. I wound them toroidally with minimum turns, just one layer of wire. The original Orbette is not as nice as the 2.0 version but was made entirely without machine tooling.
In this first video you can see the core bias magnets, 4 small NdBFes, at the "far end", most distant from the rotor, of each core. I don't really talk about these magnets in this video and I can't seem to find the one where I specifically showed how they work and what they do. As you have also found, the bias magnets reduce the current necessary to drive the core to full saturation "transparency" and so they enhance the efficiency of the motor, by allowing higher RPMs for a given input power or by reducing the input needed for a given RPM.
http://www.youtube.com/watch?v=mi_FJwpPrQk
The second video is the first of a 4-part series explaining the Orbette 1.0, the three types of Pulse Motors, and I show the effect of current reversal to the coils in realtime, by using the Secret of DPDT, as well as timing points and other stuff.
http://www.youtube.com/watch?v=WfdLC676S94
I've also done some power dissipation videos showing how to determine the actual mechanical power of the rotor itself, so that can be compared to the electrical input power. One method uses a geometric calculation of the rotor's Moment of Inertia and a chart recorder to examine the slope of the rotor's unpowered rundown rpm vs. time data, and the other method uses a model airplane propeller with known power dissipation curve as a driven load.
Thanks TK,
I feel I'm running way behind you and your research. Thanks for the links to your videos, I'll give them a watch.
Lots to digest here!
Respectfully
Ben K4ZEP
Hi Ben,
Thanks again for the details, both to my questions and for your further observations. Regarding the 11.6V DC supply voltage as a "turning value" i.e. changing the direction of the rotation, I believe it is caused by the followings:
up to 11.6V (starting from say 1-2 volts) there must be a supply voltage value at which the core goes into saturation already enough (but probably not fully) to let the core magnet do its job i.e. to give a (certain) repel kick to the rotor magnets. When the supply voltage increases towards the 11-12V level (this level is particular to your present setup of course), the magnetic field from the toroidal coil on the core just reaches a strength which already starts hampering the operation with the earlier pole polarities neded for that reverse direction run.
How can this happen? I think that under 11.7V the poles of the toroidal coil just remain mainly inside the toroidal volume, guided by the core and those poles are mainly close into each other, not influenced too much by the poles from the core magnet.
At the 11-12V level the poles of the coil must come out from the circle path and surely close onto the poles of the core magnet and if this is a 'twisted-out' flux path with respect to the earlier case, then not only the kick is gone but an attract-back force may develop during the on time of the coil at that voltage level. This is why the wiring of the coil should be changed.
However, above the 11.7V and higher, if my above hypothesis is correct, then it is the input current level which may finally give the kick (i.e. fully saturates the core AND closes the flux path onto the core magnet) with a strength and pole polarity which is correct for the kick-out too.
Of course this is a hypothesis from me, I think it can explain what you found.
One more thing: there are cores with square shape B-H curves, I recall the Philips now Ferroxcube 3R1 material developed for magnetic amplifiers etc and Elnamagnetics or (Farnell in Europe) still stock it. This is a data sheet for it: http://www.ferroxcube.com/FerroxcubeCorporateReception/datasheet/3r1.pdf and here is a 36mm OD toroidal core from that material: http://www.elnamagnetics.com/?s=tn36&type=spec (TN36/23/15-3R1) I do not know their price but at Farnell it is about 11.5 Euro (a core with OD=23mm (TN23/14/7-3R1) costs about 2.6 Euro). I mention these because these cores need the lowest input power to bring them into saturation.
regards, Gyula
Quote from: gyulasun on March 11, 2014, 08:05:06 PM
Hi Ben,
Thanks again for the details, both to my questions and for your further observations. Regarding the 11.6V DC supply voltage as a "turning value" i.e. changing the direction of the rotation, I believe it is caused by the followings:
up to 11.6V (starting from say 1-2 volts) there must be a supply voltage value at which the core goes into saturation already enough (but probably not fully) to let the core magnet do its job i.e. to give a (certain) repel kick to the rotor magnets. When the supply voltage increases towards the 11-12V level (this level is particular to your present setup of course), the magnetic field from the toroidal coil on the core just reaches a strength which already starts hampering the operation with the earlier pole polarities neded for that reverse direction run.
How can this happen? I think that under 11.7V the poles of the toroidal coil just remain mainly inside the toroidal volume, guided by the core and those poles are mainly close into each other, not influenced too much by the poles from the core magnet.
At the 11-12V level the poles of the coil must come out from the circle path and surely close onto the poles of the core magnet and if this is a 'twisted-out' flux path with respect to the earlier case, then not only the kick is gone but an attract-back force may develop during the on time of the coil at that voltage level. This is why the wiring of the coil should be changed.
However, above the 11.7V and higher, if my above hypothesis is correct, then it is the input current level which may finally give the kick (i.e. fully saturates the core AND closes the flux path onto the core magnet) with a strength and pole polarity which is correct for the kick-out too.
Of course this is a hypothesis from me, I think it can explain what you found.
One more thing: there are cores with square shape B-H curves, I recall the Philips now Ferroxcube 3R1 material developed for magnetic amplifiers etc and Elnamagnetics or (Farnell in Europe) still stock it. This is a data sheet for it: http://www.ferroxcube.com/FerroxcubeCorporateReception/datasheet/3r1.pdf (http://www.ferroxcube.com/FerroxcubeCorporateReception/datasheet/3r1.pdf) and here is a 36mm OD toroidal core from that material: http://www.elnamagnetics.com/?s=tn36&type=spec (http://www.elnamagnetics.com/?s=tn36&type=spec) (TN36/23/15-3R1) I do not know their price but at Farnell it is about 11.5 Euro (a core with OD=23mm (TN23/14/7-3R1) costs about 2.6 Euro). I mention these because these cores need the lowest input power to bring them into saturation.
regards, Gyula
Good Morning Gyula,
Up early, thinking.
I think your evaluation is right on or at least it works for me. Thanks for the heads up on the core material, It's been a couple years since I bought my cores, I'll look into them. I really need a bit smaller cores (harder to wind!). Right now I'm trying to put enough winds of #38 on them to make them about 16 ohms. Time consuming. The new motor I'm working on needs a lot of cores......so back to it after I finish my coffee.
Ben
Good Morning Ben,
The smallest OD core available in the 3R1 material is TN14/9/5-3R1, see here http://www.elnamagnetics.com/?s=tn14&type=spec but perhaps it is too small already? Not only small for winding the thin wire onto it but may go into saturation just by the core magnet, not to mention the bigger rotor magnets when in the near vicinity of the core.
Gyula
Quote from: gyulasun on March 12, 2014, 06:47:14 AM
Good Morning Ben,
The smallest OD core available in the 3R1 material is TN14/9/5-3R1, see here http://www.elnamagnetics.com/?s=tn14&type=spec (http://www.elnamagnetics.com/?s=tn14&type=spec) but perhaps it is too small already? Not only small for winding the thin wire onto it but may go into saturation just by the core magnet, not to mention the bigger rotor magnets when in the near vicinity of the core.
Gyula
Thanks Gyula,
They are pretty darn close to what I want. What I am using now is a 21mm OD X 13mm ID The saturation of the core by the core magnet and the rotor magnet is a physical problem.....So many variables here. With the core I am using now, I get about 600 gauss leakage (Gauss through the core) when touching the rotor magnet and 0 gause leakage through the core with 1/8"spacing which I am using right now. That could be brought closer to optomize the demo motor but no need to do it right now. With my core magnet, I am getting about 140 gauss leakage through which means I am starting to saturate it but room there for optomization too. But building this motor was a learning experience to me and getting up to speed on switching magnetics! I think my cores are very hi u material around 10,000. I don't remember for sure. That's what you get for not keeping good notes from 3 years ago. That 3r1 material is much lower u but has a hell of a square switching curve. If you can get right up to the knee, would take very little energy to switch. Hummmmmm. Anyway, thanks again for all the tips.
Will call the place today and get a quote on some cores.
Ben
Quote from: k4zep on March 12, 2014, 07:19:55 AM
Thanks Gyula,
They are pretty darn close to what I want. What I am using now is a 21mm OD X 13mm ID The saturation of the core by the core magnet and the rotor magnet is a physical problem.....So many variables here. With the core I am using now, I get about 600 gauss leakage (Gauss through the core) when touching the rotor magnet and 0 gause leakage through the core with 1/8"spacing which I am using right now. That could be brought closer to optomize the demo motor but no need to do it right now. With my core magnet, I am getting about 140 gauss leakage through which means I am starting to saturate it but room there for optomization too. But building this motor was a learning experience to me and getting up to speed on switching magnetics! I think my cores are very hi u material around 10,000. I don't remember for sure. That's what you get for not keeping good notes from 3 years ago. That 3r1 material is much lower u but has a hell of a square switching curve. If you can get right up to the knee, would take very little energy to switch. Hummmmmm. Anyway, thanks again for all the tips.
Will call the place today and get a quote on some cores.
Ben
Gyula,
Found the packing slip in the bottom of the bin where I keep the cores. The cores I am using is a Fair-Rite core, PN1N014PD Code 1N017. As seen here:
http://www.westfloridacomponents.com/IN017/Ferrite+Core+ID%3A+13mm+OD%3A+21mm+Fair-Rite.html, of course that is the only one there that
has no Fair-Rite catalog number.
I downloaded the Fair-Rite catalog from ELNA magnetics but can't find the cross to it to get the Spec. sheet, I'm pretty sure u of 10,000. Have a request into
Fair-Rite for help.
Ben
Hi Ben,
Perhaps if you have an L meter you could check your core (with the core magnet attached as in the motor setup) as follows: just wind 10 turns of a probe coil onto the top of the original winding, and check its inductance when the original coil is floating. Then excite slowly the original coil from your power supply and see how the inductance of the 10 turn coil reduces as the core goes towards saturation.
To approach the 160mA current draw from 19V DC input (if that is what you meant) then adjust that current value with a series resistor of a 120 Ohm (19V/160mA), though you may have to consider the peak current value and reduce the resistor accordingly. A series resistor is a must though because otherwise the supply's internal resistance would short the original coil so the 10 turn probe coil could not be measured correctly (unless the power suply has a 'current source' mode). This way you could figure out from the percentage reducements of 10 turn coil's inductance values in the function of the input voltage or current that at what input level the original coil is able to saturate the core, it would be interesting to explore the 11-12V voltage area.
I found a Fair-Rite core with your OD/ID/h sizes made from material #75, u=5000 Part Number: 5975000601 but in the u=10,000 (material #76) there was not any such sized toroid, (perhaps it is not produced as standard size any more?) The 21x13x6.4 is produced with a u=2000 and less too.
If your core has indeed u=5000 only, then its AL value is 2950nH so 10 turns on it should give 10x10x2950nH=295uH inductance if you have an L meter.
Gyula
Quote from: gyulasun on March 12, 2014, 10:34:30 AM
Hi Ben,
Perhaps if you have an L meter you could check your core (with the core magnet attached as in the motor setup) as follows: just wind 10 turns of a probe coil onto the top of the original winding, and check its inductance when the original coil is floating. Then excite slowly the original coil from your power supply and see how the inductance of the 10 turn coil reduces as the core goes towards saturation.
To approach the 160mA current draw from 19V DC input (if that is what you meant) then adjust that current value with a series resistor of a 120 Ohm (19V/160mA), though you may have to consider the peak current value and reduce the resistor accordingly. A series resistor is a must though because otherwise the supply's internal resistance would short the original coil so the 10 turn probe coil could not be measured correctly (unless the power suply has a 'current source' mode). This way you could figure out from the percentage reducements of 10 turn coil's inductance values in the function of the input voltage or current that at what input level the original coil is able to saturate the core, it would be interesting to explore the 11-12V voltage area.
I found a Fair-Rite core with your OD/ID/h sizes made from material #75, u=5000 Part Number: 5975000601 but in the u=10,000 (material #76) there was not any such sized toroid, (perhaps it is not produced as standard size any more?) The 21x13x6.4 is produced with a u=2000 and less too.
If your core has indeed u=5000 only, then its AL value is 2950nH so 10 turns on it should give 10x10x2950nH=295uH inductance if you have an L meter.
Gyula
Hi Gyula,-
With 10 turns over plain core, it is 54.63uH, therefore I suspect it is a lot less than u=5000 , possibly u=750 with a small magnet on the core, it drops about 5uh to 49uh, within 1/8" of the large magnet it drops to about 4uH....Big magnet on rotor is definitely saturating the core! I have to wind another coil as I don't want to lift the magnets off the video motor as it might break the wires as they are glued down. I'll play with the constant current power supply and see how much the big coil does around 12VDC. Thanks for the input. I'll get back to you.
Ben
Hi TinselKoala,
Thanks for the video links on your earlier Orbo (oops Orbette...) builds and tests. I went through on them and also on some earlier posts of yours when the Steorn-craze raged and I believe you must have gained a huge amount of knowledge on such setups. If you do not mind to share some chips like which is the best core material to use for instance? Is it having the square loop B-H curve or it is not a must?
[Somewhere in one of your pictures I saw 'W' material which has a u=10,000 (here is a link to it if that is indeed the core you used: http://www.mag-inc.com/products/ferrite-cores/w-material ) or you tested other core material types?]
Another question would be, could you recall what efficiency you actually measured, with the methods you have mentioned? Have you attempted to recover the collapsing field energy of the core after the current switch-off and is it included in the efficiency estimations (or that energy is so small that no worth to collect?).
Thanks, Gyula
P
@K4zep,
Really cool project. I wrapped a spiral magnetic haywire coil with magnet wire, so it looked like a wound up spring when finished. I stuck two tube magnets to each end in attraction. When I charged the magnet wire, both magnets released and dropped off. The magnets were attracted both to the magnetic haywire spiral core and each other.
Now imagine two magnet rotors, north poles on one and south poles on the other with the spiral spring coil in between. The rotor magnets on each rotor will be attracted to the magnetic wire core and to each other as well. When they're at TDC, the coil charges, masking both the magnetic material and the attraction between the rotor magnets. One pulse driving both sets of rotors!
Furthermore, a ferrite toroid, standing on end could handle four such rotors, one set for the top and the other two for the bottom with the result that one pulse would drive all four rotors. Both rotor sets attracted to the ferrite, then masked to both the magnetic ferrite and their mutual magnetic attraction by one pulse!
Quote from: synchro1 on March 13, 2014, 12:28:26 AM
@K4zep,
Really cool project. I wrapped a spiral magnetic haywire coil with magnet wire, so it looked like a wound up spring when finished. I stuck two tube magnets to each end in attraction. When I charged the magnet wire, both magnets released and dropped off. The magnets were attracted both to the magnetic haywire spiral core and each other.
Now imagine two magnet rotors, north poles on one and south poles on the other with the spiral spring coil in between. The rotor magnets on each rotor will be attracted to the magnetic wire core and to each other as well. When they're at TDC, the coil charges, masking both the magnetic material and the attraction between the rotor magnets. One pulse driving both sets of rotors!
Furthermore, a ferrite toroid, standing on end could handle four such rotors, one set for the top and the other two for the bottom with the result that one pulse would drive all four rotors. Both rotor sets attracted to the ferrite, then masked to both the magnetic ferrite and their mutual magnetic attraction by one pulse!
Sounds good to me, do you have any pictures to show the basic motor? Drawings?
Ben
@Ben,
No, I just dreamed it up thinking about your project.
Well, build it and "they" will come! What you got to loose
Ben
@Ben,
That would help keep your shop from capsizing!
Hi Gang,
You might want to watch my latest video of my miniature Thomas motor.
Same configuration, very quiet, very fast. Just a step towards my next
totally different motor, hope it is very fast, very strong, and most of all
interesting!
Yes I know, I could build it in plexiglass, make it pretty but I just happen to have
a bunch of little wooden boxes around that I want to get rid of and using them for the bases for the
motor are ok for now. Plastic will come later! Mechanics are from a $10.00 R/C motor that I gutted
to get the rotor and bearings. For now its a lot easier than turning all that stuff on a lathe.
http://www.youtube.com/watch?v=Su-v45BsFpI
Respectfully
Ben K4ZEP
Hi Ben,
Very cool, I like it and indeed no need for fancy plaxiglass in this experimental phase.
I think that not winding the toroidal core fully up with the coil (but to about 80 to 90% only) helps the operational principle be valid more thoroughly than filling up the full winding area 100%. If I can make out properly, you use a multilayer coil on both cores, maybe forced to do so to help core saturation happen at as a relatively low input power level as possible.
I wonder how the current draw increases in this setup when you apply a mechanical load to the rotor. The prop you are going to obtain will surely make this manifest.
Thanks for showing it!
rgds, Gyula
Hi All, (http://youtu.be/PklYUbv_dqw)
http://youtu.be/PklYUbv_dqw (http://youtu.be/PklYUbv_dqw)
New version of motor, lots of problems mostly with super strong ball magnet! But waveform is absolutely clean. Something is happening in the core/coil with heating and I think it has to do with the ball rotor strength. Notice large distances between core/hall effect, etc..........lots to learn here......
Also working on Wesley W. Gary magnetic motor. Patent as written will NOT work. Don't know if it is intentional but I suspect so. Fields are reversed in the patent from what they actually are at one point.
Respectfully
Ben K4ZEP
Quote from: k4zep on March 29, 2014, 10:29:41 PM
Hi All, (http://youtu.be/PklYUbv_dqw)
http://youtu.be/PklYUbv_dqw (http://youtu.be/PklYUbv_dqw)
New version of motor, lots of problems mostly with super strong ball magnet! But waveform is absolutely clean. Something is happening in the core/coil with heating and I think it has to do with the ball rotor strength. Notice large distances between core/hall effect, etc..........lots to learn here......
Also working on Wesley W. Gary magnetic motor. Patent as written will NOT work. Don't know if it is intentional but I suspect so. Fields are reversed in the patent from what they actually are at one point.
Respectfully
Ben K4ZEP
Coil had heated/shorted out........
Must make new coils.
Ben K4zep