Part of the design is relatively conventional -- a crank on a crankshaft is connected by a piston in cylinder.

However, that piston isn't directly doing work on air, it's doing work on a hydraulic fluid... the piston alternatly pushes that fluid out of the cylinder, and is pushed back by the fluid.

On odd numbered cycles, the hydraulic fluid inflates a spherical baloon inside of a spherical combustion chamber, which either compresses the gas in the chamber or performs an exhaust stroke.

On even numbered cycles, the pressure of the gas in the chamber, or the tension of the material of the balloon, pushes the hydraulic fluid out of the balloon and into the cylinder, where it pushes back on the piston.
-- goldbb, Aug 06 2009

Diaphragm engine http://www.eclectic...agm_engine_PPVG.pdf
They do exist ... [8th of 7, Aug 08 2009]

What is the balloon made of?

Also the combustion chamber is not spherical, becuase it is bounded on the inside by the balloon. Not sure what the technical term for this volume is. A hollow sphere, a shell? Surely this shape is very inefficient regarding combustion?
-- pocmloc, Aug 06 2009


So this idea is for an internal combustion engine with the addition of a hydraulic damper to absorb some of the combustion/expansion energy and convert it directly to heat, bypassing the troublesome process of doing useful work.

Or am I missing something?
-- Twizz, Aug 07 2009


But where's the power coming from? Or is there a massive engine in the background driving the crankshaft round?
-- hippo, Aug 07 2009


It seems like it would work but wouldn't put out as much power as a normal engine and I imagine the balloon-thingy would have a very short service life (10 cycles?)
-- DIYMatt, Aug 08 2009


In its simplest form, the "balloon" could be a diaphragm; instead of a piston with a sliding contact seal, the piston still reciprocates, but the diahragm prevents any leakage.

There are diaphragm pumps for liquids that work this way; no doubt, driven by a sufficent head of pressure, they would work in reverse, converting fluid pressure to mechanical rotational energy via a crank.

The key to this idea would be in the materials science of the diaphragm, which would have to be able to withstand repeated rapid flexion at high temperatures without degradation.

Consider a flat, corrugated metal plate, with a coil attached to the back, exactly like a loudspeaker - as it is wrapped around a powerful permanent magnet - and supported by a return spring. On the "gas" side of the diaphragm are inlet and exhaust valves, and a spark plug.

The engine is started by exciting the drive coil with a suitable AC frequency, while actuating the valves and the spark plug. Once the system starts, the coil will generate AC directly.
-- 8th of 7, Aug 08 2009


even == uneven,, :-),,

arti-farty way of distinguishing, 'gender' versus 'sex' in Danish 'CPR' registry, :-),

'boys' at birth/registration : 'uneven', girl babies : 'even',,

'just the last 'ziffer' as I know it,

Balloon Power is a function of Pressure, gravity 'balloons' have been used in the Norvigian/Danish history of Silver mining, like 'Coconut' gravity transmission mill, = letting in to system, One Gravity Unit, at Height H.H.hh, and letting it pull a Cord' up, lifting the Weight/LOAD',, :-) of the other side of the Cord' trolley string, mill, string, system. 'Was entered in an actual Tellyvision series of Innovative Concepts, as a 'Perpetual' machine.

s.
-- sirau, Jul 07 2011



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