Thread: new type gearbox

Saw that too...the concept sounds amazing! Have a few questions in my head about it. How would it work in a 4wd when you need to go above the "sweet spot" to get extra power when going through deep sand for example? And of course, how reliable would it be? But man it would be amazing if it can get into production! Just imagine the reduction in driveline wear!!

I know the IVT boxes in John Deere tractors are very good...maybe one day both manual and auto gear boxes will be a thing of the past.

I'm going to be following this with interest.

Here's a link to the patent.. (WO/2009/039590) A VARIABLE TRANSMISSION


trying to make sence of the patent gobblydgook talk , kind of sounds like a fancy differential???

When I saw the program, I wished the panel had asked a lot more questions. They just seemed to accept that there were no engineering problems to be overcome.

Maybe it will work, but remember the Sarich Orbital Engine. It turned out that because of its design, there were parts that could not be effectively lubricated or cooled. Just because a plastic prototype works, does not mean that you can build one that will handle hundred of Nm of torque and last for hundreds of thousands of km.

It will be great if it works, but the cynic in me says that there might be problems.

However, I say that with no engineering qualifications, just a degree of healthy skepticism.

reading through the patent... looks like its been knocked back - its been done before ?

http://www.wipo.int/pctdb/images1/PA.../0c/04f90c.pdf

There are already cars available with a continually variable transmission. A mate of mine test drove one and said is was weird having the engine stay on the same rmp's while the speed increased. Only small low power cars though, so not sure on the strength of them.

CVT gearbox

I agree, HardChina, it does look like its been knocked back. In the Written International Search attached to the patent application they have identified 4 other 'parties' who have made submissioms to the PCT, Renault being the most recognisable, and their application was dated 2005. The oldest application of the four is 1992. If I'm not mistaken DAF were the first to use a variable ratio transmission in a production car application, albiet with a rubber belt, way back before Volvo bought DAF. And I think that Nissan - through their amalgamation with Renault - were the first in more recent times to use a steel chain for their CVT.

I would suggest that Mr Durnin's 'invention' is more a clever piece of engineering design rather than a fresh, new invention with novelty attached. My perception is that it is a good design, and well worth consideration by car makers. But I can't see that it is anything new; it still has gears, shafts, rotational movement etc like any other transmission. It just doesn't use a 'belt' to vary the ratios.

I think honda had something similar in it's CRV

I wonder how these things would go with engine breaking??

What happens when the wheels are applying torque to the engine via these fancy transmissions? Weird concept