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This is a re-invention of the Toyota Prius transmission. What is missing is the varible speed second shaft (with one planet instead of a full set) has to deal with torque and energy. This announcement failed to consider the transmission under load and the torque and power into or out of the second shaft. the Prius completes this torque path with a pair of motor generators.

Study a Pius transmission and then examine this planitary gear transmission. The Prius uses a full set of planets, a Sun, and ring.

His uses 1 planet (see any unbalanced mass and torque problems?), a Sun, and Ring. He notes the variable ratio just like the Prius. All that is missing is the motor generator pair to take care of the torque the second shaft requires.

A Prius is engine driven into the planet ring. The sun turns a generator (sometimes motor) and the output is on the ring gear which is fed the power generated by the sun gear generator.

His has the engine drive the planet ( notice any thing like the prius? ) and varying the speed of the Sun Gear, (the Prius uses a motor/generator to vary the speed) so the speed of the output ring gear can go from full speed, to stop to reverse (again just like the Prius).

Has the patent office looked at prior art on this? It has already been invented. The Prius version is complete and in production.

Prius calls the planitary gear system a power split device.
http://eahart.com/prius/psd/

So buy a Prius. It has the same mechanism in it. The two drive sources are the gasoline engine and a motor-generator MG1. See an animation of it here: http://eahart.com/prius/psd/

I see a lot of people have chimed in without knowledge of how the Prius HSD works. There is NO conventional belt CVT in a Prius.

Prius works almost exactly like this demo. Gear Driven Planetary and Sun gears.

The HSD with its robust gear system without friction drive is what makes it so special.

Here is a simplified demo of how the Prius HSD works:

http://eahart.com/prius/psd/

There's nothing new here, except for the fact that this gentleman has attached some additional rods to a planetary gear system.

And no, the Prius does not use a belt cvt as folks seem to think it does.

http://eahart.com/prius/psd/

You've gotten a number of replies already but I'll say two things that I didn't see covered:

1. The Prius physically cannot have a manual transmission. It is a "continuously variable" transmission (for efficiency purposes), so there are no discrete gears to shift between. More details here, including cool interactive animations: http://eahart.com/prius/psd/
2. You can still shift an automatic transmission car into neutral and coast to a stop on the side of the road. It just requires driver awareness and presence of mind in an emergency situation. On a related note, deaths due to "sudden acceleration" seem to disproportionately affect older drivers: http://overlawyered.com/2010/03/toyota-acceleration-why-im-skeptical/

Downshift? Not a Prius... there's no shifting, ever. Single speed gear box, no transmission. The effective gear ratio is set by the behavior of the small electric motor/generator, MG1. Check out this site, which includes a simple model of the system: http://eahart.com/prius/psd

Neutral had always meant "physically disconnect engine from wheels"

http://eahart.com/prius/psd/
So it is impossible to "disconnect" the engine from the wheels of the Toyota Hybrids, it is a direct gear to gear connection between the engine and wheel. But it takes the electric motor making some torque to make the car move, not sure if you would call that physically disconnected?

That's actually incorrect. While the Prius is parallel, the design of the transmission is such that the engine can be made to run at a specific speed regardless (mostly) of the speed the wheels are turning. A Prius can go about 60 MPH with the engine running at 1000 RPM (its minimum), and can go about 15-80 with it held at 2000 RPM (probably in the ball park of its most efficient).

There's an article here, complete with flash app showing how it works. It's rather ingenious.

The Prius' CVT seems to be mechanically simpler than a conventional automatic transmission. AFAIK there are no clutch plates, no torque converter and only 1 planetary gearset. I took some pictures of FWD and RWD automatic transmissions and put them up at http://priuschat.com/index.php?showtopic=30245&st= 0&p=403617&#entry403617. You can look at what the Prius' CVT/PSD (power split device) look like a little further down and at http://privatenrg.com/#Planetary_Gear. http://eahart.com/prius/psd/ has some more info and a simulator.

A Prius doesn't have an alternator, the inverter works to charge the 12V aux/accessory battery. It doesn't have a starter either, MG1 acts as the starter.