can someone direct me to a part of this forum that might be able to help me with this

You're are getting a lot of replies that are not addressing your problem, so here comes my solution...When an Electromagnet is energized, you will have a N and a S pole...reversing the polarity (+ to - and - to +) will reverse the poles. This can be easily verified by passing a compass across the poles...the needle will deflect L to R say. Reversing the polarity, the compass needle will deflect R to L
signifying that the polarity has been reversed. This should clarify the answer to your question.

Cheers, DPW [ Everything has limitations...and I hate limitations.]

 

Yes! I can if you can prove the theory, "North polls attract South poles and South poles attract North poles" false.

why would I want to disprove the theory that I am trying to use to make this work?

 

You're are getting a lot of replies that are not addressing your problem, so here comes my solution...When an Electromagnet is energized, you will have a N and a S pole...reversing the polarity (+ to - and - to +) will reverse the poles. This can be easily verified by passing a compass across the poles...the needle will deflect L to R say. Reversing the polarity, the compass needle will deflect R to L
signifying that the polarity has been reversed. This should clarify the answer to your question.

Cheers, DPW [ Everything has limitations...and I hate limitations.]

the tread has evolved a little lol. Now I need some help turning a hall effect signal into a command to switch polarity on two electromagnets in time with a earth magnet moving between them.

 

With the magnet values you are wanting to start with, you will have some failure, IMO. 600 and 450 pound attraction magnets are not something I would prototype with. The inductor(electromagnet) currents will not want to reverse very fast.

You are going to have to do some research for yourself on "electronically commutated" motor drives or converters. I know there are tons of literature on the web from my own research. But none of it will be on reciprocating magnetic motors, you will have to adapt a rotary commmutating scheme to your plan.

 

ya I figured I would have to have the sensor on the crankshaft somehow and I tried to research how to make my electronics work but couldn't get anywhere with my wording of the search I will try "electronically commutated" motor drives or converters and see if that gets me more useful information. If the electromagnets wont switch polarity quickly enough I guess I could try to just turn them on and off from distances that would still attract the magnet but then I would have to over come the earth magnets hold on the iron core of the electromagnet which would really cut down on torque the electromagnets not switching quickly enough would be a big problem I will have to see how long it would take my electromagnets to switch polarity. thank you for your help on what to research

 

https://www.google.com/search?q=sol...urce=og&sa=N&tab=wi&ei=oX7PUbqAGeq5ygGkw4CADg

Perhaps these will spark some ideas for you

 

https://www.google.com/search?q=sol...urce=og&sa=N&tab=wi&ei=oX7PUbqAGeq5ygGkw4CADg

Perhaps these will spark some ideas for you

I thought about the solenoid type motor for him, but they use a slug of steel/iron for the piston. Pretty simple, made one back in high scool. The OP wants to use a magnet instead of a steel slug, way harder to make it work.

There are "alternative energy" guys working on them and a few patents for them, but nothing successfully more than a toy. The OP is talking about using a 600 pound pull permanent magnet!

 

i have seen the v8 solenoid driven motors before they are pretty neat i ran across them trying to figure out how to switch my h bridge the cams they have seem to work pretty good but they wont work for my project i was hoping someone had a way to switch the h bridge that was not computer controlled. also I wasn't really expecting much more than a toy out of it i just had the thought and decided to try to do some research and see if i could build it and make it work there are lots of aspects to this that i admittedly don't fully understand but i think that's the reason for doing things like this is to learn something while having a little fun doing it i think right now my biggest problem with this idea is the fact that the poles on the electromagnets wont switch instantly along with lots of other problems lol but that seems to be the biggest. also short bus could you possibly point me in the direction of some info about the motors that use a permanent magnet instead on a slug of steel thanks

 

i found a video of something similar on youtube it looks he is moving the electromagnet back and forth though its the same principle with the magnet moving i just want to have all the forces of the magnets working at the same time to give the most power possible but this the basic jest of what i had in mind
http://www.youtube.com/watch?feature=player_detailpage&v=IBsWN-IV9hg

 

The Youtube video is kind of how I was going to suggest you do it. Two perm magnets and one moving electromagnet. What he has with the spindle for the electromagnet solid would be changed in my suggestion though. In stead of the coil being free and the spindle solid, I would mount the coil solid to the spindle and have both the coil and spindle move together. Then the spindle would connect to a connecting rod to move a crank. Like in a steam engine.

But I would never invest in big magnets to start with. The ring magnets from a couple of old car speakers could be had for next to nothing. And most of them are pretty powerful.

And a single coil is cheaper to wind than two coils. But your coil will still need two windings on it. One end would be wound clockwise and the opposite end counter clockwise. This is needed to give opposite polarity on each end.

You won't be able to use hall sensors either. They are polarity dependent. So to use them you would need four of them, a north and south at each end. But that gives another problem, as soon as the coil polarity switches it would trigger the other hall sensor and switch coil polarity. So the coil wouldn't move, just sit and vibrate.

Optical sensors would be the way to go IMO. For the motors on Google, use the term in the Ytube video, "reciprocating magnet motor".

 

Black01, these may be of interest to you;

http://www.google.com/patents/US20080012432

http://www.youtube.com/watch?v=tM_HRwqKzFk

http://www.google.com/url?sa=t&rct=...AND-DEVELOPMENT.pdf&ei=xZ3RUdOQBIm0yQHG0IHoDA

http://www.theowlnest.com/piston.html

http://www.magneticenergy.org.uk/Magnetic Piston/Magnetic Piston.htm

http://electro-magnetic.webs.com/index.htm

http://www.wondermagnet.com/recipmotor.html

This is my personal favorite. The ones you want are about half way down the page.

http://www.sparkmuseum.com/MOTORS.HTM

 

thanks everybody for your help and all the great references I have learned a lot in the last week and I haven't even started building anything yet.

 

thanks everybody for your help and all the great references I have learned a lot in the last week and I haven't even started building anything yet.

That's the way it's done. Interest ---- Idea ---- Research --- More Ideas --- More Research --- Spend Money on Prototype --- Repeat as Necessary.