Author Topic: Household PM motors (Read 2797 times)

Big All · « **on:** January 22, 2005, 11:11:29 PM »

So what household items commonly have permanent magnet motors in them?

I'm looking for anysize motors, like cassete tape motors to large appliances.

I seen mentioned on this site, someone using a motor from a lawnmower, would they have converted it from an induction to pm alt?

I'm particularily interested in larger appliance motors not just for generation but also for electric bicycles.

rotornuts · « **Reply #1 on:** January 22, 2005, 07:23:56 PM »

I'd be very interested to hear what people suggest for an electric bike. I've long wanted to build one. My biggest problem is speed control. I have no idea how to build a PWM controller and I'm not sure what else will work well. As far as I know brushless dc motors are rare in larger sizes. How adout a 12V car starter motor for a bike?

What would dictate draw on the battery? Would it be more a factor of motor speed or total load regardless of speed. If the second is true I'll run the motor through the bikes sprockets off the pedal crank and let the motor run full rpm.

Can we easily build DC PM motors from induction units and build simple controls to run them?

Big All · « **Reply #2 on:** January 22, 2005, 08:19:19 PM »

I've read of starters being used for scooters & stuff. The problem is starters are intermittent use, and have brushes that burn out pretty quickly when run continuously.

johnlm · « **Reply #3 on:** January 22, 2005, 09:48:40 PM »

If you check out the size of dc pm motors being used in all the scooters / mini razor motor bikes, etc available everywhere anymore it looks like they are using anywhere from 150W to 350W motors. There are not too many pm mag motors of that size in typical household items. The (battery powered) lawn mower sounds as close as any. Auto electric fan motors are probably only around 50 to 100 W sized I would guess. The best bet migh be to try to find a used electric scooter that has been crashed or whatever at a garage sale and pick it up for a reasonable price and salvage the motor. Or maybe a used 12V winch motor might work. They are probably 100 to 200 W depending on the size and strength of the winch.

John

wooferhound · « **Reply #4 on:** January 22, 2005, 10:47:09 PM »

Look for "Hub Motors"

Here is a google search for Bicycle Hub Motor

http://www.google.com/search?hl=en&lr=&q=bicycle+hub+motor&btnG=Search

and here is a picture

pyrocasto · « **Reply #5 on:** January 22, 2005, 10:47:40 PM »

If you can get a good motor, like off the scooter or something, it would be best to stick it on a mountain bike. If you put the original sprockets on the motor, you could have 21 gears. If you just use one sprocket, you could have the back 7 gears. That way you can go fast, and climb those steep hills.

rotornuts · « **Reply #6 on:** January 23, 2005, 12:33:32 AM »

my 93 f-150 has its origional starter if we say that I start my truck twice a day every day for 12 years that motor has done around 26 hours of hard operation. I think it would do ok for a while on a bike. Besides old starters are you guessed it FREE. Only problem is power consumption?

hiker · « **Reply #7 on:** January 23, 2005, 03:21:24 AM »

picked up a 1980 moped a while back--the points were thrashed on it--plus its missing

a few parts..had a 300watt 12volt motor laying around --so i mounted it to the moped..

tops out at about 11- 13 mph...no speed control -just tap the switch on and off..

the motor is not a pma motor..

hiker · « **Reply #8 on:** January 23, 2005, 03:23:21 AM »

should read --the motor is not a pm motor--

Big All · « **Reply #9 on:** January 23, 2005, 03:24:48 AM »

$25.00 to free is about my budget for any tinkering toy that doesn't feed me or have a very short ROI. Of course for tinkering, free always has the best ROI when you count the giddiness gained in finally finding it.

From the prices I found those hub motors brand new are for lottery winners or something.

pyrocasto · « **Reply #10 on:** January 23, 2005, 04:46:19 PM »

I just need to find a mountain bike that no one wants, and I'm going to convert it. I think a fan motor from a car should work, but we'll have to see. If this thing works good, I'll be riding it to work for awhile.

skravlinge · « **Reply #11 on:** January 24, 2005, 12:33:28 AM »

A 300 to 600 watt dc-motor should be easy to get hands on. A DC-motor can have an easy and cheap speed controll. Found one page in Englsh of a speedcontrol:

http://www.electronickits.com/kit/complete/motor/ck1400.htm

Surplus motors can be found here:

http://www.aaaim.com/CandH/index.htm

pietko · « **Reply #12 on:** January 24, 2005, 02:58:28 AM »

Please have a look at this link:

http://www.hta-be.bfh.ch/~fuchs/Transmission/af_e_k.pdf

If we could make electric motor and generator of higher efficiency (95% +) we will have effective chainless drive and so many gears as we wish- its will be stepless gear.

Any thoughts about construction? Hub generator should have been of about 200W at 100rpm and hub motor of about 500W.

nothing to lose · « **Reply #13 on:** January 24, 2005, 08:53:46 AM »

I never hear much about used equipment motors ??

Ya know it seems to me if we are using Batteries salvaged used from forklifts, floor scrubbers, golf carts, etc.... then those should have some pretty beefy motors that run on Batts!! What are they and where can we find some? I'd like to get working on an electric bike and car both. I did find an electric lawnmower this weekend in a junk pile, haven't checked the motor yet. Are most of those PM motors as I heard, this is not a battery mower, it is 120v where you have to drag that extension cord around.

picmacmillan · « **Reply #14 on:** January 25, 2005, 04:51:14 PM »

the only motor that comes to mind that they use around here is an old weed wacker gas motor and they hook that up to the back wheel of the bycicle...i guess they get phenominal gas mileage and they go like a pack of dogs on a three legged cat!...pickster

solarbbq · « **Reply #15 on:** January 28, 2005, 09:19:54 PM »

HI guys and gals

I've just ordered a 200w (360w peak) hub motor from a factory in china,

it should arrive in next week or so. Didn't bother with ordering over the net

just contacted a factory directly, it came to about $250 Australian dollars for motor, controller pwm, throttle controler (batteries to heavy to send by airmail).

will keep yas posted on how it goes.

By the way, hub motor kits ordered via internet sites have a huge mark-up.

Seems to me chinese labourers are just more and more exploited.

I realise that the ideal of alternative energy use is nice,

but in reality we're all caught up in this world economy.

brett

solarbbq · « **Reply #16 on:** January 28, 2005, 09:21:27 PM »

oh forgot to say the $250 aud included the air freight tooooooooo!!!!!!!!

in fact half of the price was due to airfreight

nothing to lose · « **Reply #17 on:** February 17, 2005, 01:28:08 AM »

I wonder what that would be in US dollars?

If this post aint to far burried can you post the company info you bought from, I may check them out.

junkyarddog · « **Reply #18 on:** November 03, 2006, 09:28:35 PM »

i dont know bout pm motors but i do know bout starters. the problem is that they have no cooling fan and run hot real quick so continuos use might be wasted efort may be the wiper motor would be better need a couple. just a thought

RP · « **Reply #19 on:** November 03, 2006, 09:45:07 PM »

Junkyarddog,

You do realize this thread is almost 2 years old...

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Author Topic: Household PM motors (Read 2797 times)