Puzzling delimma
Puzzling delimma
(OP)
I am trying to prove a hypothesis. I have a neodymium magnet(6Lbs of pull force) mounted to a rod, magnetized axially, south end outward(facing away from the rod mount). This "pushrod" device slides through a tube toward a fixed-mounted electomagnet(specifications to be determined). This is part of a 1/5 scale replica of a steam locomotive, and will be explained in the following theory statement.
Here is the theory:
If the pushrod (which is mounted to the wheel of the loco), is pushed into the guide tube and comes to top dead center, and this electromagnet is activated (same pole N-N, or S-S), the repulsion force will drive the "piston" to bottom dead center with enough force to cause torque, movement, and complete the rotational cycle.
Now the reason for asking. I am not extremely fluent in electronics, or electromagnetism principles, and that being said I would like to know how would I go about getting the above sequence of events to happen at a controlled RPM?
Specifically:
1)What electromagnet design will work with enough force if supplied with 12VDC/20A, using 22AWG ceramic-coated wire, confined to the physical dimensions of .625" O.D.(on the side facing the "piston" magnet) X (length TBD). This will be a rapid cycling electromagnet, and longevity is a factor.
2)Since this is going to be a continuous use type situation, heat buildup needs to be addressed.
I know this is a very bizarre question to be asking, but I have simply exhausted my limited knowledge here, and need to reach out to someone who may be able to help provide direction, and be kind enough to "blue-collar"-it for me. It's difficult to really explain what I need, but I hope someone can decipher my cryptic query.
Thanks
Here is the theory:
If the pushrod (which is mounted to the wheel of the loco), is pushed into the guide tube and comes to top dead center, and this electromagnet is activated (same pole N-N, or S-S), the repulsion force will drive the "piston" to bottom dead center with enough force to cause torque, movement, and complete the rotational cycle.
Now the reason for asking. I am not extremely fluent in electronics, or electromagnetism principles, and that being said I would like to know how would I go about getting the above sequence of events to happen at a controlled RPM?
Specifically:
1)What electromagnet design will work with enough force if supplied with 12VDC/20A, using 22AWG ceramic-coated wire, confined to the physical dimensions of .625" O.D.(on the side facing the "piston" magnet) X (length TBD). This will be a rapid cycling electromagnet, and longevity is a factor.
2)Since this is going to be a continuous use type situation, heat buildup needs to be addressed.
I know this is a very bizarre question to be asking, but I have simply exhausted my limited knowledge here, and need to reach out to someone who may be able to help provide direction, and be kind enough to "blue-collar"-it for me. It's difficult to really explain what I need, but I hope someone can decipher my cryptic query.
Thanks





RE: Puzzling delimma
RE: Puzzling delimma
This will get hot. Imagine a 240 watt light bulb. You need to heat sink it with aluminum and a fan.
RE: Puzzling delimma
the unanswered questions:
> What drive requirements are there, i.e., how power do you actually need? While a 1/3 hp engine might just barely be adequate to move just the locomotive itself, passengers and additional cars might be too much. A VW Bug has a 40-50 hp engine
> Are you going to overpower the drive wheels? Since you don't have the weight of the boiler(s), metal drive wheels might slip on the track, and you may need rubber drive wheels.
TTFN
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RE: Puzzling delimma
RPreble: That was what I was thinking, but needed another person's opinion. As for the heat, I am leaning towards an encapsulated sealed water jacket around the electromag.
IRstuff: An electromechanical piston is exactly what I am trying to do here. The loco itself will weigh in at 47lbs, and the wheels are in fact rubber coated for that very reason! It wasn't always that way, but trial and error has precepted necessity :)
Here is another argument I am debating with a collegue:
Having a cylinder-shaped core in an electromagnet attains an even electron flow directionally trough the length of the rod (common electromag 101), but what if the shape of the core were more conical (like the shape of the Apollo lunar capsule, of sorts), and the coil direction started on the wider end, flowing to the narrower end? As the coil spiral decreased in diameter, would the electron flow(and therefore the magnetism) get more dense and create a more compacted field on that end, i.e.- a stronger magnetic field?
I haven't tried this yet to win or lose the debate, but just thought I'd throw that out there for any educated opinions.
Thanks again.
RE: Puzzling delimma
RE: Puzzling delimma
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