Motoped. HPC typhoon build

[Hummina Shadeeba]

I have a motor design I’m excited about that’s almost finished but hoping to hear feedback


the bike and the motor it came with:

https://www.upzy.com/products/hpc-typhoon-pro-electric-bike?variant=3380117504026&country=US&currency=USD&utm_medium=product_sync&utm_source=google&utm_content=sag_organic&utm_campaign=sag_organic&gad_source=1&gad_campaignid=744346688&gbraid=0AAAAADkGPoV4toDOFFxQoUp6WUySAykXM&gclid=EAIaIQobChMIhLTOif7mlQMVAA2tBh0Y4RM0EAQYAiABEgLZ4vD_BwE

The motor was broken and not the right kv anyway.

 

[Hummina Shadeeba]

The goal is get air though the red shaft hole, out the back of the blue ring of holes into the motor, across the motor airgap, then thrown out the bronze side with the impeller.

I didn’t add the stator and magnets in these drawings



The 4 holes in the red hub/shaft are to feed the wires in and then out under the big bearing.


mount the two shaft ends with lots of bolts, grin all-axle style. The amount of aluminum supporting/surrounding the bolts is not enough according to standard engineering practices but looking at how brake rotors and sprockets are mounted on wheels this seems adequate. What u think?




The two stator-holding halves (blue and red) I’ll glue together while held in an alignment jig.


The blue hub and gold rotor side is the drive side. The grey (21t 8mm pitch) pulley mounts to the gold side plate.


The blue and red shafts will be permanently bolted to steel plates that bolt to the frame and I can adjust tension by moving the plates



The blue and red hub parts are just 3mm thick aluminum other than the shaft ends and maybe they should be thicker toward the center

I haven’t come up with an impeller design and this is just to show and I’ll print different iterations to test.

 

[Hummina Shadeeba]

Many little bolts like I showed above isn’t how ur supposed to hold things if u don’t have to do it that way. Mating features or splines would work but that’s often complex and really u want to use a shaft clamp. When using many bolts theyre pulling the two mating surfaces together and the friction between the two faces is what stops the movement and if somehow you end up relying on the actual bolts aluminum will quickly ovalize and threads rip out . All those many m4 and m3 bolts even if properly tightened or even into steel are not nearly as strong as a shaft collar. There’s a lot more friction and at the biggest circumference. With shaft collars on aluminum it’s considered fine to even have that soft aluminum shaft as thin as 20% of the outside diameter.

There’s different types of shaft collars and what I’ll use is “face mountable”


Anyone who knew anything about what they were doing would know this is how it’s done especially with aluminum.



I’m finding Alexa is my only guide but also finding she’s great and can do all the torque calculations based on dimensions and even asks good relevant questions


some magnet makers in China made me aware they no longer are allowed to sell high-heat magnets to USA. Funking politics these days but seems they’re not all complying.

 

[Hummina Shadeeba]

Decided on two same size shafts. 30mm od. 18 id. The smaller. I think better for cooling ironically as space was being taken from the length of fan blades.

The motor mounting plates are threaded for m4 bolts to hold scoops I’ll print.




wires will just go out the shaft and trying to get under the bearing is silly.


Gunna heat shrink the hub halves together, and stator on top, n drill for pins after. Should be fun with dry ice n boiling water. Assuming the parts are actually made that precisely


Paying $300 for simulated structural analysis and fluid dynamics work. Want to make sure the fan inside is optimized. As far as I know at this point it could even be detrimental.


Extended the mounting plates and lowering the motor so can fit a bigger fan. It’s a pretty big external fan and my goal is to do 70mph continuously. Maybe that’s way beyond feasible but with the stator sitting on an aluminum heatsink that has air blown through it and then the air coming back across the windings.. I’m hoping