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Let's Build a Hybrid Cycle


GAHD

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Lol, gahd, latex is no harder then html, so if you need help figuring it out, gimme a pm, i'll put some material together if you are having trouble ;)

 

Gahd, you probably should get a small brushless motor with good response and gear it down, just direct gear it and you will get very little loss, most electric cars, including the X1 are geared, its a single gear yes, and they still claim direct drive...

 

Things to consider:

batteries, like the crazy lithium ions used in the X1 prototype, they are biodegradable, which is cool, but also, they provide a ton of power for their size, and they should fit in the frame of your bike, no prob :)

 

you should consider weight, or rather lighten the bike as much as you can, the lighter you get it, the more efficient it gets (but hell you would know that). You can probably make a huge reduction in weight (relative ofcourse to the bike's weight) if you take off the pedals, and the rear wheel gears and change to a much more simplistic hub. Also decrease the rear tyre thickness to a road tire, and also run road tires on the front, on road (and i am assuming you are building this contraption as an alternative to scooters) you get better traction and smoother roll with a smoother tire. Another thing to think about are spokes, they are usually steel, you can switch out for some aluminum ones to once again, save on weight.

 

 

a small, but highly efficient (well as efficient as you can get it) solar charging system will extend your range on a sunny day, but do consider that you will want to plug the sucker in to charge it.

 

also i think simpler is better, i saw your first thought on solenoids and perma magnets, and some other designs, think about building everything into the wheel, just keeping the power source outside (whether attached or inserted into the frame is up to you (this is for better weight distribution), then you have to design 2 things, a motor-fork linkage, because a part of the motor will have to be kept in place to rotate the wheel, and a wheel, at this point you would probably be better off with a non-spoked wheel, that will fit your bike (you can make it more or less standard). with a simple hub design, you should be able to put a gear on an axle (which you will have to put in the hub, though nothing too crazy here), and a shroud, to protect both motor and the drive mechanism from the environment.

 

I dont think this project is undoable, infact if i were any closer, i would definitely volunteer to help with building a prototype, but as i said, i tend to think, at least in mechanics, simpler=better, well, most of the time, more efficient. But dont confuse "simpler" with "too simple", i'm the guy who takes a "too simple" idea and after making it "simpler" by adding parts, figures out better linkage for a height-adjustable wind turbine (linkage worked in my mini model, but the guy ended up getting a standard windmill, but whatever, i got the concept, and it would be cool to build :P )

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Any progress?
Ditto that.

 

Belovedlife’s post in the engineering forum and alexander’s bump in this thread got me to thinking that it’s been a few years since “motor in wheel” systems from major manufacturers, like Siemens eCorner, appeared in the news. I wonder if any of them have made it to any kind of market, or better yet, into junkyards (maybe the exotic kind found in university engineering buildings), yet?

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oooh, ooh how about a compressed air motor and drive system, like in the european compressed air cars.

 

Start with mounting a [math]88ft^3[/math], 4500psi carbon fiber air tank

then the fun of designing an ultra small, rotary compressed air motor, that will be small enough to fit in the wheel, but still spin fast enough to be able to, when geared down, drive you with some, perhaps fairly significant speed (at 4500psi, you dont need a hell of a lot of air to drive it) by the way (www.engineair.com.au for motor design ideas)

 

this way you fill the tank with compressed air, it makes no electro-magnetic pollution, it makes no noise, until you push the throttle, which will open up a pressure valve it up and propell you forward :)

 

juust another thought and since the motor will have to be mounted on the forks, you really dont have to worry about air line getting twisted, as long as it runs with the forks and has some play in it, it should not effect your steering :)

 

Juust another idea :)

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oooh, ooh how about a compressed air motor and drive system, like in the european compressed air cars.

 

Start with mounting a [math]88ft^3[/math], 4500psi carbon fiber air tank

then the fun of designing an ultra small, rotary compressed air motor, that will be small enough to fit in the wheel, but still spin fast enough to be able to, when geared down, drive you with some, perhaps fairly significant speed (at 4500psi, you dont need a hell of a lot of air to drive it) by the way (www.engineair.com.au for motor design ideas)

 

this way you fill the tank with compressed air, it makes no electro-magnetic pollution, it makes no noise, until you push the throttle, which will open up a pressure valve it up and propell you forward :)

 

 

 

juust another thought and since the motor will have to be mounted on the forks, you really dont have to worry about air line getting twisted, as long as it runs with the forks and has some play in it, it should not effect your steering :)

 

Juust another idea :)

(although the effieciency of use of the compressed air would be inquestion using this tool below)

could you just use on of the pnumatic air tools meant for heavy machenery (ie diesel)

the hook up a worm drive to the tool so you have the tool in line with the frame

and the pnumatic connected to a worm gear the that drives the tire

or get the air tool already focused at a 90deg angle

 

then you wouldn't have centripital values to worry about

you could just get the air tool from any auto store

and the tank

well you could get one of those carbon fiber tanks that are light and are capable of storing like 20,000 lbs/sqin of hydrogen

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Oh please, how much more fun is it to design and build a rotary engine yourself, versus hacking up a perfectly fine air tool. Also with a rotary engine, there is nearly any vibration, if any at all, it's not your typical piston air engine...
Besides the fact that most air tools are EXTREMELY inefficient:naughty: Bear in mind that an air powered die grinder which has at best the same power as a Dremmel tool or a cheapy drill motor requires a minimum of a 1hp motor driven compressor just to run it in short bursts. So wastefull.... Much better to design your own.

(at 4500psi, you dont need a hell of a lot of air to drive it)

It may not seem like much but 4CFM at 4500psi is a hell of a lot more than 4CFM at say 10psi...

 

 

 

(course I fixed that problem here, my die grinder has a 48cc trimmer engine:hihi:)

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good point, its just the whole milling of the block that hinders that

 

but you could take the design of the air tool and make it more efficient

or you could just get the air tool and make the inner componets more accurate

in dimention to make it more efficient

 

i just thought that if money was a factor, then the air tool would be the cheap way to go

not as efficient

but readily availible

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The primary issue is getting an ideal seal without increasing friction and wear to levels which negate any gain...the problem with typical air tool motors is that they leak pressure like a sieve (blow-by) until they get enough [b]pressure[/b] and volume to operate typically 5 to 9CFM @90+psi.....and even then under load they leak and waste power.

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is that a fundimental flaw in the desighn, or a desighn aspect needed for the tool?
A fundamental flaw of design, primarily for profit yield, secondarily because the fellers that came up with the design for whatever reason decided it was good enough long before giving it enough thought to catch the errors of their ways.:shrug:

 

It really is a good foundation for an air motor design but serious rethought need be applied to how the slides (pistons) and rotor seal to each other and the housing, also the inlet and exhaust port flow should be parallel to the rotation of the motor rather than the oddball perpendicular layout found in many tools or the paralel in perpendicular out flow.

 

 

Of course a liquid refrigerant powered rotary which uses atmospheric heat to convert it to a gas and then an electric compressor to squish it back to a liquid would be super cool....use the evap. to cool the refrigerant holding tank so the compressor don't have to work so hard and use the condenser to heat the rotary....while ye rat it use the heat from the alternater and compressor motor to provide more heat to the evap. side....yah .....won't run forever but prolly a lot longer than compressed air and at much lower pressures....I call it the atmospheric heat steam engine (the steam being R134A or similar in gass form)

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i know for efficient transfer of liquid oxygen to gas

it is more efficient to use a coil of tubing, for my purpose we get more efficiency

in gas form than liquid because you have more efficient combustion and less waste oxygen

the liquid form has too high of a concentration of oxygen vs fuel

 

now in theory, atmoshere could be condensed to a liquid, but all the gasses are liquid at different

pressure and temp (STP)

and if you compress atmoshere in any form you get water

which if you use a compressor in any job you know you have to bleed the water out of the

tanks

 

but you could use the transfer of heat from the friction of the pnumatic motor to give a little extra

force to the compressed air right

 

anyway this is getting way off topic

 

but do you think if you had a pnumatic tool

and you took it apart

that you could fabricate the inner parts to closer tolerances

so you could use the same block, just machine it to have more accurate tolerances?

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Absolutely, and not....the problem is sloppy fit and no seals for the rotor itself....you can machine in space for rotor seals but there really isn't anything you can do for the sloppy fit of the sliders particularly once they start wearing....which without an inline oiler or periodic oiling will wear very fast....as a welder I primarily use electric tools because of this...you don't want your grinder spitting oil residue all over the parts your in the process of cleaning.

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No....I don't see any practical manner in which you could make that work, efficiently or otherwise. you could filter the exhaust and collect the oil in a separate tank but that's about it and will cost you big in back pressure and lost propulsive force.....and BTW you'll still lose oil to the atmosphere...of course in a completely sealed system it wouldn't matter....hence my fondness for R134A and other refrigerants...lower pressure in liquid state than air (a couple hundred psi vs thousands psi), low boiling point, and lubricative properties:) To get a 4500psi tank filled to pressure would take one hell of a compressor an create one hell of a bomb...R134A can be readily compressed by relatively small and efficient motors like those found on a typical electric scooter powering a typical automotive A/C compressor....properly set up you'd be lookin at a few minutes of battery time to a few minutes on cold power...possibly double or triple range in a hot day.

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so using the present pnumatics would not only be inneficient, but also polluting

well i looked at that link posted earlier

mabe it would be cheaper to buy one of those

 

plus why doesn't that company in france offer to sell their engins individually

instead of having to buy the whole vehicle

i know weight of the vehicle is one of their varyables

but it would be nice just to be able to adapt their motor to my transmission

replace my gas tank with a compressed air tank

and be on my way

 

wow, we are off topic here

 

so it would be easier to machine a pnumatic motor then adapt current tool teck

that makes a huge difference

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This talk of compressed air motors on bicycles reminds me of an odd one a bike collector friend of mine showed me.

 

The precise origin of the bike was uncertain – it had a head badge listing a no-longer-existant Baltimore, MD, USA store, but likely wasn’t built there. Its wheels, rims, crankset and 3-speed hub was from an 1950s Raleigh. It’s frame, which was steel, appeared handmade. Best guess dated it at from the late ‘50s to early ‘60s.

 

The bike had an air compressor/motor driven by a wheel that could be engaged and disengaged from the side of the front tire. It looked much like an oversize electric generator, an accessory commonly used to power lights on bikes through the ‘70s. Two air hoses attached it to a thumb-operated valve on the handlebar that allowed the rider to select a compressor (brake), closed, and motor position, another hose connected to the frame’s top tube, via a hand-removable coupling.

 

Compressed air was stored in the frame’s top and down tubes, which were larger diameter than usual, but not extremely, looking about like a modern-day Cannondale. A small metal line behind the head tube made an air connection between the top and down tubes.

 

You could flip the compressor to engage the front wheel with the thumb switch in compressor mode to use it as a brake, compressing air in the frame. Switching to motor mode gave you 10-20 seconds of a low-speed “hill climbing assist”. You could also detach the hose to the compressor/motor from the frame, and replace it with a hose with an air chuck on one end to use to inflate the tires.

 

It was fairly quiet in compressor mode, ear-splittingly loud in motor mode. Opened the thumb valve with the motor disengaged from the wheel made it to spin like mad. The valves and hose couplings got too hot to handle, but never to cold to handle. Overpressuring the frame-tank appeared to be prevented by the compressor leaking when it reached a maximum pressure.

 

The compressor/motor was lubricated with ordinary light machine oil, through uncapped holes.

 

I’ve not been able to find any mention of this bike on the internet, other than occasional forum posts claiming either to have seen it or similar bikes, or claiming that their existence is a myth.

 

My other favorite compressed air-powered vehicles are my dear, departed Air Hog toy airplane, and various of the vehicles in existence today (see the wikipedia article “compressed air car”). The tiny Air Hog engine was expecially nice, because it was made of clear plastic, so you could see how its piston, crank, and valves worked.

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