Using Elliptical trammel for opposed cylinder engine

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  • Thread starter Thread starter The tin man
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SUMMARY

The discussion centers on the feasibility of using an elliptical trammel design for an opposed combustion engine featuring two vertical and two horizontal cylinders. While theoretically possible, practical challenges such as bearing lubrication issues due to high surface velocity and balancing difficulties at high speeds are significant barriers. A flat boxer engine with a quadrature crankshaft is suggested as a more compact alternative. Additionally, the design resembles a radial engine but would require a two-stroke configuration to function effectively without a closely coupled flywheel.

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  • Understanding of engine design principles, specifically opposed cylinder configurations.
  • Knowledge of elliptical trammel mechanisms and their applications in engineering.
  • Familiarity with bearing lubrication challenges in high-velocity applications.
  • Basic concepts of balancing mechanisms in multi-cylinder engines.
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  • Research the design and mechanics of flat boxer engines with quadrature crankshafts.
  • Study the lubrication systems used in high-performance engines to mitigate surface velocity issues.
  • Explore the principles of balancing in multi-cylinder engines, particularly in radial and opposed configurations.
  • Investigate two-stroke engine designs and their advantages in specific applications.
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The tin man
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Question I'm sure theirs a reason this hasn't been done but why couldn't you use an elliptical trammel as a design for an opposed combustion engine where 2 cylinders are vertical and 2 horizontal and have the cylinders combust in separate loops wouldn't that technically do the same thing in principle as long as the pressure fed in a loop
 
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You could use an elliptical trammel in a four piston engine.

The reason it is not done is probably because of bearing lubrication problems, due to high surface velocity.

The engine would be more compact if it was built as a flat boxer, with a quadrature crankshaft for the two journals.

Maybe a diagram of your idea would help find references to that style of engine.
 
I think balancing the assembly at high speed might be difficult as the two cylinders would need to be offset (and the crankshaft as well). Or you would need multiple two-cylinder trammels to balance each other?

Otherwise, it would look a lot like a radial engine with fewer pins needed. In the following animation, the link with the 5 pins would be the rod between the two pistons; The middle of that rod being connected to the crank pin.

800px-Radial_engine_timing.gif

(original animated GIF)
I also found this but I have no clue what the engine looks like.
 
Last edited:
Without a closely coupled flywheel, the four piston engine would need to be of two-stroke design.

Four-stroke radial engines need an odd number of cylinders, usually greater than six.
 

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