I've been looking for small gears for a project and I ran across some strange ones.

The manufacturer doesn't say what they are used for, but someone might be able to guess.

Double elliptical


Multiple Shapes


"Corn" Gears provide motion in two dimensions

 

 

I was going to post the same video! Saw it years ago.

I spent some time touring factories in Switzerland many years back. Some of the precision mechanics they come up with for automated mechanical processes are amazing.

 

Maybe worth a repeat.
Max.

 

There is also the 1868 classic,
Five Hundred and Seven Mechanical Movements: Embracing All Those which are Most Important in Dynamics, Hydraulics, Hydrostatics, Pneumatics, Steam Engines, Mill and Other Gearing, Presses, Horology, and Miscellaneous Machinery.
https://books.google.com/books?id=vOhIAAAAMAAJ&printsec=frontcover#v=onepage&q&f=false

 

There is also the 1868 classic,
Five Hundred and Seven Mechanical Movements: Embracing All Those which are Most Important in Dynamics, Hydraulics, Hydrostatics, Pneumatics, Steam Engines, Mill and Other Gearing, Presses, Horology, and Miscellaneous Machinery.

I had that on my wish list order from Lindsay Publications before they went under.

 

I had that on my wish list order from Lindsay Publications before they went under.

There is one on AbeBooks for $7.50!
Max.

 

Speaking of gears, this video popped up in my YouTube suggestions the other day.

Pretty cool technology, actually.

 

Speaking of gears, this video popped up in my YouTube suggestions the other day.

Pretty cool technology, actually.

This is close to what I've been trying to invent for a long time. They need one more feature, and it would be perfect:

As the input torque increases, automatically reduce the gear ratio. As such, it would be a fully automatic continuously adjustable transmission capable of maintaining constant torque on the drive motor regardless of load. That would be super neat.

 

This is close to what I've been trying to invent for a long time. They need one more feature, and it would be perfect:

As the input torque increases, automatically reduce the gear ratio. As such, it would be a fully automatic continuously adjustable transmission capable of maintaining constant torque on the drive motor regardless of load. That would be super neat.

Damn, that's friggen brilliant man!

 

Damn, that's friggen brilliant man!

The idea came from peddling my bike. I hate switching gears -- and the associated ratcheting sound and discontinuous pedal motion (and the trial and error of quickly finding the most comfortable gear).

My vision was that one could adjust the torque at which one wished to pedal, and the transmission would automatically and continuously adjust to maintain that torque -- with the associated pedaling rate increasing or decreasing smoothly as inclination and/or road/trail surfaces change.

 

The idea came from peddling my bike. I hate switching gears -- and the associated ratcheting sound and discontinuous pedal motion (and the trial and error of quickly finding the most comfortable gear).

My vision was that one could adjust the torque at which one wished to pedal, and the transmission would automatically and continuously adjust to maintain that torque -- with the associated pedaling rate increasing or decreasing smoothly as inclination and/or road/trail surfaces change.

I had a similar (though way less inspired) idea to incorporate one of those conical variable transmission gears to a bike for that very same reason. But that adjustment for torque idea never crossed my mind. And even though it would require adding some electronics to something like a bicycle it would be well worth it, I think. Just imagine how much easier it would be to transition from downhill to uphill. Plus the little servo could probably be powered directly by the rider's pedal stroke.

 

And even though it would require adding some electronics....

No! I want it to be purely mechanical and passive.

Back to the video: if he can add a spring loaded actuator to the adjustment ring, with a lever that moves as a function of torque, this would be a perfect solution.

 

No! I want it to be purely mechanical and passive.

Back to the video: if he can add a spring loaded actuator to the adjustment ring, with a lever that moves as a function of torque, this would be a perfect solution.

Oh, well yeah, that would be awesome. It's kind of hard for me to visualize just how exactly that would work though. I'll see if I can find some videos on that sort of thing and maybe I can understand what you mean a little better. Either way, it's a good idea.

 

@joeyd999
When I was a kid my dad bought me a 5hp go kart. It had 5" tires, 1-wheel drive, and it would dig a hole in the ground with the 1 driven wheel if you mashed the gas. When I got older I wanted to go faster so he made some redneck mods to it. He installed a live axle on pillow block bearings and put riding lawnmower rear tires on it (20" tires?). The result was that the go kart barely had enough torque to take off from a stop. If there was any upward incline at all, I would have to push the go kart to get it rolling, and then hop on and floor it. But the top end speed went from maybe 15mph to 50mph. to remedy the low end torque problem, he installed a "torque-a-verter" which is essentially a miniature automatic CVT. Then I could burn out with those big rear wheels and still hit 50mph. It was pretty awesome, and I think if you dissected one of these torque-a-verters (assuming it wouldn't work for a bike right out of the box - who knows, it might), you would have all the inspiration you need for your bike drive. Unfortunately that probably also means you were beat to the patent office.

https://www.gokartsupply.com/tavapp.htm

 

Unfortunately that probably also means you were beat to the patent office.

It's not something I would strive to patent. But I cannot see why an adaption that is bicycle compatible would be outright rejected by the USPTO, especially if the adaptation is unique wrt prior art.

 

I had that on my wish list order from Lindsay Publications before they went under.

Lindsay still had a lot of books I hadn't bought yet. Never seemed to get around to doing an order untill it was too late.

 

Lindsay still had a lot of books I hadn't bought yet. Never seemed to get around to doing an order untill it was too late.

Same here. I did get the gingery home machine shop from scratch 7 part series though. That was #1 on my list so no big deal.

 

Lindsay books may be dead, but the books live on - https://www.youroldtimebookstore.com/

 

Lindsay books may be dead, but the books live on - https://www.youroldtimebookstore.com/

Excellent link, shortbus! ... you've made my day...