Power feed using wheelchair and scooter motors

[pineywoods]

Lots of interest here on this subject, so here's my 2 cents.
Motors..
Wheelchairs use 2 motors, one for each drive wheel. Built in gearbox, usually worm drive, but occasionally find one with spur gears. Permanent magnet fields, switch power leads for reverse. Built in disk brake with a twist. Apply 24 volts to the brake winding to release the brake. Also have a manual brake release lever. Easy to remove the brake if not needed. Designed for 24 volt DC operation, but may be adequate on 12 volt power. Output shaft serves as the axle for the main drive wheels, heavy duty bearings to support entire weight of chair plus occupant. Current draw on 24 volts usually in the 35 amp range, more for bigger chairs.
Scooters are a bit different, one bigger motor driving a spur gear box plus a differential to drive the 2 rear wheels. Electric brake same as the wheel chair motors.  Also 24 volt but run ok on 12 volts with less power. Runs in either direction by switching the power leads..Current draw can be high as 60 or 70 amps on 24 volts..

I have a lot of experience with these motors, questions, drop me a pm

Speed controllers are a whole nother ball game, I'll cover those in a separate post to keep the post size half way manageable.

[larrydown60]

I am watching to see what I can learn

[Kbeitz]

I also play aroung a lot with PM motors.
I would like to add another one. 12v Tarp motors.

As for controlers I really like this one and the price is right.
I have around 200 hours useing these controlers with no problems.




 

Tarp motor...



 

[svart ole]

Just remember that if you are using something like this in a application where you start stop and change direction you need to think about how to ramp the speed up and down.  The laws of motion and inertia come into play and too much slam bang makes things fall apart. I have been around long enough to appreciate a well designed and implemented frictions drive. Some times low tech is good.

Another option for a drive is a low buck Harbor Freight winch. Machine the drum to take a keyed sprocket. Watch your duty cycle on them though as they where never intended for continuous duty.   

[Kbeitz]

Just remember that if you are using something like this in a application where you start stop and change direction you need to think about how to ramp the speed up and down.  The laws of motion and inertia come into play and too much slam bang makes things fall apart. I have been around long enough to appreciate a well designed and implemented frictions drive. Some times low tech is good.

Another option for a drive is a low buck Harbor Freight winch. Machine the drum to take a keyed sprocket. Watch your duty cycle on them though as they where never intended for continuous duty.   

I can vouch for that.... First thing I did was to remove the electric brakes.
I also have spring loaded stops at the ends of the mill.



 

And for the winch to lift the carrage I drive a worm winch so it stops when the motor stops.



 

[Kbeitz]

I wish I could find a drawing on how to make my own heavy duty PM controler with out
all the fancy stuff. I know it can be done with just a few parts.
I have some 100 amp mosfets just laying around.

I cant wait to see what i can learn here.
I really glad someone is maybe going to show us all some new tricks.

[fishfighter]

Thanks for posting this. Have a lot to learn. I will be doing a automation on my mill, but I really want to keep things at 12V. Still looking at wheelchair motors, but everything I found has been 24v.

[Kbeitz]

Thanks for posting this. Have a lot to learn. I will be doing a automation on my mill, but I really want to keep things at 12V. Still looking at wheelchair motors, but everything I found has been 24v.

The wheelchair motors will run on 12v. You will loose some rpm and torque.
I also wanted to stay with the 12v system. But I found a 24v alternator single wire
on e-bay cheap so I went with the 24v system. Glad I did.

[Ox]

Subscribed.  This thread is a fantastic idea!

[Ga Mtn Man]

I wish I could find a drawing on how to make my own heavy duty PM controler with out
all the fancy stuff. I know it can be done with just a few parts.
I have some 100 amp mosfets just laying around.

I cant wait to see what i can learn here.
I really glad someone is maybe going to show us all some new tricks.

All the "fancy stuff" is what keeps a properly designed speed controller from destroying itself.  Google "Open Source Motor Controller".  Lots of good info there.