New Engine Design! A head with rotating valves.

[dieselstation]

The Coates Engine. The spherical rotary valve system is made up of spheres rotating on a shaft sandwiched between a split head. These spheres are either chain or belt driven via the crankshaft, much like an overhead camshaft. Each sphere rotates against a matching seal between it and the piston, one for intake and one for exhaust. The spheres have cavities and ports machined into them for the induction of fuel and air on the intake stroke, and the evacuation of fired gases on the exhaust stroke. This design performs exactly the same function as poppet valves, but the design eliminates the poppet valves, valve springs, guides, camshaft, pushrods, rocker arms and other smaller parts. The Coates engine operates with over 100 fewer parts than convention engines.


Advantages include:
-Lower Emissions
-Better Mileage
-Reduced Lubrication Requirements
-More Power
-Reduced Noise & Vibration
-Adaptable for Alternative Fuel
-Reduced Manufacturing Costs

Man this engine looks REVOLUTIONARY! 14,000 RPMs! This looks to be the engine of the future. More information at their website:
http://www.coatesengine.com/index1.html

pictures:
http://www.coatesengine.com/eGallery/images/pic03.jpg
http://www.coatesengine.com/eGallery/images/pic06.jpg
http://www.coatesengine.com/eGallery/images/V-8engine.jpg
http://www.coatesengine.com/eGallery/images/components.jpg

 

[Demon-Xanth]

I thought that's what the "ROTAX" engines were

 

[Viper GTS]

I thought the biggest limitation of RPM's was the fact that the pistons have to withstand tremendous g-forces to change direction that quickly. Rotary engines, of course, don't suffer from this but you'd still have that problem with this engine.

Viper GTS

 

[Thegonagle]

I can see it in my head and I imagine that it would be a nightmare to seal the valves properly for the expected life of a modern engine (200,000+ miles). I can see it being a big time oil burner, too.

All those claims have been made before by the "inventor" of every "revolutionary" new engine, but they have rarely come to fruition.

Bleh, I'm so freaking pragmatic!

 

[duke]

While on the topic of new engine designs, I found this very interesting.

 

[Howard]

This isn't really new. You can also check out ballpistonengine.com

 

[Howard]

And, with the Coates type engine, it'd be very difficult or impossible to develop a VTEC/VVTL system. I suppose one wouldn't be all that important if this type of head is brought to market.

 

[Demon-Xanth]

One additional downside that I can see, is that the airflow doesn't have a very clean path. A limitation on RPM with a rotary engine was that the triangle "piston" effectively wobbled in the oval "cylinder", there's a limit on how fast this wobble can happen. Turbines have a limitation due to thier bearings, when turbines go catastrophically everyone around knows it because it starts a cascade of destruction internally (bearings go, shaft moves, blades hit the casing and break off, shaft is now out of balence, causing more blades to break spewing shrapnel through the rest of the engine...), unless it's in the lucky case of a siezure. Either way the engine is toast. Two cycle engines have the problem of incomplete combustion. They make for VERY dirty engines, this fact got them banned in many lakes after california mandated MTBE be added, then found that MTBE polluted the water. Some two strokes get by with effectively no moving valves, but use a reed valve to allow intake to happen on the bottom side of the cylinder during an upstroke, then having the downstroke push the air fuel mixture into the cylinder as the exhaust gets pushed out the other side following combustion (you can see why it's dirty). There's other designs of two strokes, but they all pretty much fall prey to the "intake+combustion+exhaust combostroke" phenomenon.


man, I need to get a life...