5kW hub drive motor! (Washing machine DIY E-bike)

Vikingimike01

Active Member
Joined
Jul 1, 2018
Messages
738
Hey forum!

So the drum of our old (like 8 year old at most) washing machine broke. So I took the chance, and took the engine out.

It's a 365 watt, 120 volt, 1.6 amper engine. I wired it up, and connected the positive and negative to a small battery I got for my headlight on my 2 stroke motorized bike.

It ran. Pretty fast. But! No torque. Like at all. If I hold onto it, it's very easy to stop it. How can I increase torque? Keep in mind, this is a pretty old engine. Was thinking to make a generator like a wind or something out of it at first, but gave that idea up.

The battery was a small, like palm sized, cubic lead acid battery. 12 volts, 5.5 amper hours. Fully charged.

Do I need more of these 12 volt batteries, and then wire them up like that, or, should I get a bigger 12 volt battery, with more amper hours? Should I rewire with more windings, or thicker copper wire? There's like a centimeter of air gap that I can maybe use up (Not quite sure if theres a reason behind having that)

I was thinking of getting more smaller batteries to reach that 120 volts.

Thanks in advance!
 


Vikingimike01

Active Member
Joined
Jul 1, 2018
Messages
738
Hey guys! I took a better look inside, there's actually not much space left to put more turns. It was dark, and I didn't see the black magnets.

Any other ideas? I was reading up on this, found out that overvolting is the best (But worst for the engine) way to create more power.

Also found this:
86558


Where KW is the kilowatt the engine makes (New, old self explanatory)

Oldturns is the number of turns before winding it again
Newturns is how much new turns there are
 

mark20

Active Member
Joined
Sep 26, 2018
Messages
510
Hey guys! I took a better look inside, there's actually not much space left to put more turns. It was dark, and I didn't see the black magnets.

Any other ideas? I was reading up on this, found out that overvolting is the best (But worst for the engine) way to create more power.

Also found this:
View attachment 86558

Where KW is the kilowatt the engine makes (New, old self explanatory)

Oldturns is the number of turns before winding it again
Newturns is how much new turns there are
i would get more 12v batterys, wire them up in series. as 12v is really not enough (36v is the most common, 48v is stronger but you might fry the motor, unluckly but possible)
if you have the $ get 2 6s lipo batterys and wire them in series. and bam you have close to 48V and the motor will be fast!
the torque is multpied by the amount of voltage you have. (theroretily)
good luck!
 

Vikingimike01

Active Member
Joined
Jul 1, 2018
Messages
738
Thanks! I just checked the label, and it's actually for 240 volts. Oof.

What do you mean
the torque is multpied by the amount of voltage you have. (theroretily)
Does that mea, if I have 1nm of torque at let's say 10 volts, I'd have 2 at 20, 3 at 30, so on?

EDIT: Also it is AC since it's from a washing machine. And most batteries are DC.
 
D

DMC

Guest
AC motors rely on alternating current (constant positive to negative swing) to provide the proper magnetic field within the motor windings. The only solution i can think of would be to use an off the shelf power inverter, but you'll probably need a bigger battery than the one you currently have (you'd need at least a 12V 10-15A battery just to give enough juice to power the motor, and would probably need at least 10X that current if you want the battery charge to last a decent length of time. ) In other words, you might be stuck needing a motorcycle battery to make it work. Other than that, you also need some kind of way to vary voltage to the motor for throttle control (a rheostat would work ok, but an AC variable drive motor control circuit using an SCR or TRIAC to drive it would be far more efficient).

Hope that helps, and good luck!
 

Vikingimike01

Active Member
Joined
Jul 1, 2018
Messages
738
I found a converter online that says: 240 volt AC = 152.640 volt DC. So this is how much I'd need? Oh god seems like a lot. What if I get cells and solder them up, like AA battery cells?
 

mark20

Active Member
Joined
Sep 26, 2018
Messages
510
Thanks! I just checked the label, and it's actually for 240 volts. Oof.

What do you mean

Does that mea, if I have 1nm of torque at let's say 10 volts, I'd have 2 at 20, 3 at 30, so on?

EDIT: Also it is AC since it's from a washing machine. And most batteries are DC.
well, you see, the motor is deisgned to handle high voltage, you can get a power inverter (dc 12v to ac 110v, or double that and get dc24v to ac 220v)
so you would only need 2 battrys and you will get the voltage. a 500w inverter should do fine, just look out for cheap fakes!)
also, you need to set up a controller to make the bike stop and go (a lightswitch is the most skeckyiest but its super simple, heres another one https://www.amazon.com/Throttle-Control-Electric-Scooter-Pocket/dp/B01N1N29T0, but you need to set up a sensor (or just dont connect it. that would make it on and off, like the light switch execept a lot less scechy.)
 
Last edited:

Vikingimike01

Active Member
Joined
Jul 1, 2018
Messages
738
That is very smart! I don't know anything about electronics really, but thanks for the tip. I'll ask my DIY shop around the corner tomorrow, or an electrical shop. What amperage battery would i need? Is 4.5-5.5 amper hour OK? Would it deplete it quickly? It's just a lead acid scooter battery that fits in your palm (10x10x10 cm size)
 

Vikingimike01

Active Member
Joined
Jul 1, 2018
Messages
738
Also, I just saw that you edited it. I was thinking, there are those turnable light switches that you can get, the ones that you can use to adjust light brightness. Would one of those work?
 

mark20

Active Member
Joined
Sep 26, 2018
Messages
510
Also, I just saw that you edited it. I was thinking, there are those turnable light switches that you can get, the ones that you can use to adjust light brightness. Would one of those work?
that could work, i was thinking about the ones that go up and down.
also your engine is a 1.6 amp/h and your going to use a 4.5amp/h battery
you would get about a 2 and 1/2 hours. but the voltage will drop cuntinuaslly, so you will be slowing down the more you ride. i think it should last but keep in mind the inverter takes some juice out of the battery as well. so about a 2 hours of riding (on paper, you will have to test it in real life)
 
Top