• Hello ES! We could use some help to get us past the finish line on building the new knowledgebase for the forum.
    Can you donate? Please see our fundraising page. Thank you!

HUB MOTOR Magnet attachment.

RIPPERTON

Regular
Joined
Feb 26, 2013
Messages
316
Location
Sydney Australia
Photo spread of mechanical magnet attachment I used in my 12kW QS scooter motor.
After a few heavy heat cycles the Loktite in my QS Hub Motor loosened off and allowed
the magnets to skid around the rim / back iron. Taking off from a standing start the
Hub made a jittering static kind of noise and felt like a clutch slipping.
Oddly, this fixed the cogging or rough starting the scooter had probably because of the
trapezoidal Kelly controller. I didnt want to reglue the magnets and possibly have them break off again later.
Also reglueing them meant removing all the magnets off the rim which is very difficult and could chip them.
Instead I came up with a mechanical attachment method that cant break off.
Luckily the magnets wernt as wide as the rim so playing around with the magnets pushing them side to side
I figured I could stagger the magnets one left and one right and weld a block or stopper in each gap.
So each magnet now pushes on a block. The heat from the MIG welding didnt damage the magnets and
the staggering didnt effect the hall sensors.QS HUB MAGNETS.jpg

BLOCK LASERS.jpg


MAGNET BLOCKS 2.jpg
 
Last edited:
The block secures the magnets on 2 axis, circumferential and axial.
Meaning they wont move around the hub under drive force and they wont move sideways.
But the magnets are not secured radially ie they could lift off the back iron and move toward the stator.
When I dismantled the motor I did not see any signs of the magnets clashing with the stator.
Means even though the electro magnetic field is pushing and pulling the magnets, they dont lift off the back iron.
In production you would machine the rim and side plate castings to have a stagger and bevel
that traps the magnet in a radial direction as in the 3D image.

NO GLUE HUB.jpg
 
Last edited:
I don't think staggering the magnets like this is a good idea. It imposes magnetic flux across the stator lamination which will create a lot more heat.
 
Magnets "impose magnetic flux across the stator lamination" whether they are staggered or not.
The motor wouldnt work if there was no magnetic flux penetrating into the stator.
There will still be the same amount of heat generated in the motor.
 
Magnets "impose magnetic flux across the stator lamination" whether they are staggered or not.
The motor wouldnt work if there was no magnetic flux penetrating into the stator.
There will still be the same amount of heat generated in the motor.
I think you're missing the point. Ask yourself why we bother with laminations atall. Why not just use solid steel?

I'm well aware that magnets make flux penetrate the stator but I'm also well aware that the number of motors with staggered magnets is approximately zero, for good reason. Think harder.
 
I think you are simply fabricating a vapid point out of thin air.
Staggered magnets have no effect on stators laminated or otherwise.
If you are aware that magnetic flux penetrates the stator, then why do you think
there is a problem with a staggered magnet arrangement. Makes no difference which
is proven by the fact that my Hall sensors are still registering properly in sequence.
I think you are missing my point that magnet staggering is solely for the purpose of
mechanically attaching magnets to the rotor of a Hub motor eliminating need for glue.
Also not found in your register, the obvious reason that the number of motors
with staggered magnets is (1) is because staggering magnets is an I N N O V A T I O N.
My scooter motor is the first in the world with this innovation. I invented it !!!!
Ive even sent pics to Harry of QS Motors in China who sold me the motor.
Thats what this thread is for, but youve turned it into a clown show with you as the
shining star. Delete all your posts and get some rest.
 
Dampened yes but to the point where I couldnt feel any roughness of the original cogging.
All that got absorbed by the magnets getting shoved, sliding around the rim.
You can imagine how much grip the magnets have even on a smooth surface.
The magnets stopped sliding about 10 to 15kmh, same as where the cogging stops.
The cogging has returned as it was before the magnets broke loose.
I didnt really expect the cogging to be fixed by the stagger.
 
I think you are simply fabricating a vapid point out of thin air.
Staggered magnets have no effect on stators laminated or otherwise.
If you are aware that magnetic flux penetrates the stator, then why do you think
there is a problem with a staggered magnet arrangement. Makes no difference which
is proven by the fact that my Hall sensors are still registering properly in sequence.
I think you are missing my point that magnet staggering is solely for the purpose of
mechanically attaching magnets to the rotor of a Hub motor eliminating need for glue.
Also not found in your register, the obvious reason that the number of motors
with staggered magnets is (1) is because staggering magnets is an I N N O V A T I O N.
My scooter motor is the first in the world with this innovation. I invented it !!!!
Ive even sent pics to Harry of QS Motors in China who sold me the motor.
Thats what this thread is for, but youve turned it into a clown show with you as the
shining star. Delete all your posts and get some rest.
Right. I could make my wheels out of jelly and declare it an innovation because no one's done it.

The flux in a stator needs to flow in the plane of the lamination. The laminations are there to avoid Eddie currents. If you sweep the flux the wrong way, you create Eddie currents in the stator. Then it gets hot. Then it feels damped, because it is. That's what Eddie currents do, they resist velocity, which is the definition of a damper.
 
Right. I could make my wheels out of jelly and declare it an innovation because no one's done it.

Yeah but then you would get 5hitcanned off the forum for CloWnaS5 behaviour.
I rollin my Staggered Scooter down to Accor stadium tonight for the AC-DC show. 🤘
 
Back
Top