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Schpankme,
I did a simple simulation of your core ... Here are the results:
Thanks,
Jetijs
Jetijs,
Looks like were winding the cores on the inside.
New Project Motor
o Have you decided on motor Dimensions?
o Wonder if there's an "Off the Shelf" Motor to use?
o What's your price for shipping me a new motor kit (stator & rotor)?
o This is the perfect time for others to join in.
Schpankme,
# I think I will increase the outer diameter of the stator from 100 to 120mm that is the size of a CD. I need it to be a little bigger because of the shaft and bolt diameter issues. I do not know about the thickness yet, it all depends of the material and cuttng costs. I think the thickness will be 60-100mm, that is 120-200 plates (if I will het them at 0,5mm thickness).
# I do not know if there is any off shelf motor that could be perfectly suitable for this. Steven tried to convert a simple induction motor core, but we do not know the results yet. As you can read in previous posts, such a off shelf induction motor stator core is a real pain to wind. Also the poles could be too close together. Tomorrow I will see what the guys form the motor rewinding company will tell me, maybe they have something that is more suitable
# You are going a mile a minute. I haven't even built one myself yet, so I can not tell you how much the shipping of such items will cost. I haven't even thought about selling these cores. At first we must built and test one motor an see how it performs, that could take some months.
# You are going a mile a minute. I haven't even built one myself yet
Thanks,
Jetijs
Jetijs,
Having watched the Electric Motor Secrets DVD and Youtube supplements; I'm interested in 'building along' with you and others, with the same motor design/theroy.
... recommend using just four poles.
... pole face to the rotor 60 degrees of arc, with a space of about 30 degrees of arc to the next pole.
... "bar rotor" defining 60 degrees of arc with two flat sides defining 120 degrees of arc.
Peter
Peter,
The motor attached was drawn, using 30 deg increments, to your specifications. This motor is the size of a CD (120 MM DIA), and might be nice if made 120mm Length (?).
My guess on Coil size would be Bi-filar wound, with as many wraps as we can get in the limited space ?
Since the 'holding force' of a magnetized piece of 'whatever' is defined by the actual field strength intensity and surface area, it is better to have your stator fingers like this (see attached) in relation to your rotor.
Schpankme,
I agree to Steven about this. You can imagine the magnetic flux as a liquid or water and the core material as a water pipe. You can see that in the case of your motor, the poles are the thinnest parts, that is like there is very small diameter pipes. That will cause some resistance to the flow.
Anyway, today I was at this motor winding company and got my silicon steel plates. The plates are 0.35mm thick and I bought about 18 kilograms of the steel, that should be more than enough for a 120mm diameter core with 60mm thickness. Here's a picture:
I paid about 15$ for these plates, I think that this is very cheap
Also I saw the whole winding process and it is exactly like Steven said, they wind those coils on a separate machine and only then put them into the core:
Also saw some pretty impressive size motors there, this one for example is a 75kW motor:
They have a lot of smaller motors there, but they all have the same type of stator cores and nothing of what they have is suitable for our purpose.
So now I will design the motor in 3D and see how it looks. And then off we go to the laser cutter
... 'holding force' of a magnetized piece ... defined by the actual field strength intensity and surface area ...
Steven
Steven & Jetijs,
I agree with your description of the magnetic flux flow and the improved Stator design; my concern was the limited space available to build an appropriate size coil. Upon reflection, the better design would use a Stator as you've described and increase motor diameter if additonal coil space was required.
HI
I would just like to thank Peter for sharing this idea that has got us all thinking about doing something. I am like many out there that are following this forum and working on a motor but have not shared my progress.
I am using a 1/3 hp AC induction phase 1 motor that is readily available at yard sales. I happen to have one from a broken drill press.
It had a stator core with 24 poles. I removed every other one to 12 (hacksaw). Very low tech. this was to make the winding easier and allow time between pulses. The idea is to pules 6 at a time. and to use Steven's suggestion to change polarity on each pulse. The core is an aluminum and steal mix. it had a smooth surface so I marked it for 6 points that are slightly larger then the stator and removed the rest with a grinder. Sorry I have no fancy machining equipment. If it doesn't work I will have to have one made. The affect of this type of core will be interesting to say the lest.
I am in the process of winding the stator with 22 gage wire and 20, 2 wire winds. Peter's Idea of doing this in 12 separate windings came just in time. I will try running with 12 volts first, then increase to 24.
I plan on following Jetijs excellent work with the circuit design. using the photo switch and a CD with slots attached to the end of the pulley.
I am having a great time learning about electric motors and circuit designed.
twoody,
good job! I love your pictures and can't wait to see the results of your motor. How big is the airgap between stator and rotor in your motor?
Thanks,
Jetijs
It's better to wear off by working than to rust by doing nothing.
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