Engine design question

I have a (relatively) simple design question for a project I am playing with. I have hit a brick wall, and I can't figure it out, I've been looking at it too long.

Where would you go to simply, easily, quickly get an answer to this?

I've posted older pictures of the interior of my contraption at

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(it will take a minute to load up, so if you have a dialup, be patient - it loads SolidWorks to view the contraption)

When it all loads up, click on "rotate" & you can move it all around to view at any angle.

HERE IS THE NEED;

The planetary gears revolve around the center of the two ring gears. Attached to these planetary gears are shafts, and what amounts to "lobes" or "Cams" are attached to the shaft. These cams are 3-sided.

At 12 points around the circumference, each lobe reaches TDC (Top Dead Center). At these points, these lobes contact a metal rod to push it up

32mm. As the lobe rolls by, it gently lowers it back down to meet the next, oncoming lobe. However, I am concerned that, at the speeds this will rin, this will beat the living snot out of the engine.

I am willing to completely design the lobe, the impact surface, anything, to make this a quiet(er) smoother less wearing function.

I am willing to offer a reward to the design I use, or mention you on the design/site.

Michael Papp President iNet Lending Group

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Webmaster The Other Rotary Engine Page

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Webmaster The SplitCycle Engine

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Reply to
Canzie
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You are probably right. You didn't mention the operating frequency of the cams, I suspect it's quite high. In order to use this design, you need to design a cam profile rather than the 3 rods which the model shows. The disadvantage of the rods is that they impact the follower producing massive momentary acceleration. Design a cam which will give smooth acceleration of the follower assembly. There is also a requirement not to vary the rate of acceleration too quickly as this can induce flexing and higher harmonics in the assembly. Might I suggest that a designer of automotive cams be approached since that is what you are trying to achieve. The other point to consider with cams, is the returning force. A cam only drives in one direction. A spring or other device holds the follower on the cam surface. This device must be capable of maintaining follower to cam contact at full rotational speed. Failure results in the follower floating off the cam profile and the sudden re-establishment of contact takes the form of an impact with the problems mentioned above. The only exception to this is the Desmodrinic system where two cams are used to drive in opposite ways. Effective but expensive.

John

Reply to
John Manders

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