Piston rings

[rockym]

I've just been studying a rather fantastic engine described at

http://www.pvengine.com,

and the basic concept seems OK. However, I am curious about some of the statements. My main question is about the possibility of such an engine being able to contain the pressures of combustion. It is easy to picture how rings work in a regular engine, but how could they possibly work across two slipping faces like in these unusual pistons?

 

[franzh]

Forget about the piston rings. How do the pistons connect to any type of driving mechanism, such as, the crankshaft?

The process of machining a seal-able torriodial chamber is difficult enough, but add in a slot for any direct connection to a rotating component (ring gears?) makes any effective sealing out of the question.

Franz

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[rockym]

Related to the crankshaft, have you had a chance to read the details in the web site's pdf file? Yeah, agreed, toroidal chambers would be a bear. However the ring gears are contained within the same unitized structure as the pistons, while being isolated at the same time with continuous rings. This is shown in the figures -- but very poorly. Also, I'd guess the single pair of rings shown in the figures would be inadequate. But doubling (tripling) the pairs should solve that issue. Note they are double-grooved -- not single as in a normal cylinder/piston combo. So..., I think sealing the piston crowns is the greater problem. Also, I see I goofed by not posting this under the mechanical seal engineering section.