New, simpler valve arrangement for compressed air engines

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cfellows

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This is a new variation I came up with on my slave exhaust valve for compressed air engines. The slave valve is the same, but instead of a poppet or displaced ball for the inlet valve, it uses the much simpler rotary valve found on many simple steam and compressed air engines.

This valve consists of a milled flat, either on the crankshaft, or a separate cam shaft if something other than a 1:1 ratio is desired, as in a four stroke operation.

When the milled flat rotates into alignment with inlet port, high pressure air is admittedmitted to the cylinder throught the void above the flat and the port which leads to the cylinder. This high pressure air displaces the ball valve in the head, closing off the exhaust port and allowing the high pressure air into the cylinder.

When the milled flat rotates out of alignment with the inlet port, near the bottom of the stroke, the high pressure air supply is cut off and the spring in the head returns the ball bearing to the right, allowing air from the cylinder to exit through the exhaust port.

This design can also be used for 4 stroke or 6 stroke or what ever, because as long as the high pressure air supply is shut off, the exhaust port will remain open.

I have a 4 cylinder opposed engine on the drawing board right now which will use this valving arrangement for 4 stroke operation. Hopefully I can start work on it soon.

RotaryValve.png


Chuck
 
Very ingenious. I don't see why that wouldn't work. There is a likelyhood of the spring not moving the ball fast enough at high RPMs, but any valve train under spring tension will have that limitation.
 

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