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Old 12-26-2009, 09:18 PM   #15 (permalink)
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Quote:
Originally Posted by NeilBlanchard View Post
Yes, it is a cam driven engine, like the Revetec (that I mentioned earlier). The problem with a crankshaft engine is the maximum pressure occurs when the connecting rod in nearly straight up, and there is very little leverage that can turn the crankshaft. (A lot of force is trying to bend the crankshaft...)

With a cam driven engine, you can design the amount of leverage you have; rather than being locked in to a sinusoidal piston motion.

On the Shepard engine, is the combustion sleeve inside (and concentric with) the rotating cam sleeve? I wonder why the levers are required at all, then?
Check out Honda's R-series engines. The crank is slightly offset, so TDC is actually slightly aft of traditional crank angle, and the combustion pressure builds when the piston/rod assembly would be creating a leveraged force on the crank shaft.
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