Late Era Enclosed Steam Engines

[GreenTwin]

are you sure it is rocking and not rotating?

Never say never, of course, but I am not aware of any reason for it to rotate.
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[Jasonb]

Pat if it is a rocking valve which I am sure it is then go look at your Dads engine with the rocking valve. It is really just like a slide valve except the port face is curved.

Very unusual to us ean eccentric to drive a lever if you want predictable rotation. If the engine were started when the eccentric is at the top or bottom of it's throw then the valve could end up rotating either way!

Two where I have worked it out for myself and both run OK

 

[SmithDoor]

You can see pretty consistent casting wall thickness in these sections.

I think the webs that were previously discussed are a result of maintaining a thin wall in some parts of the casting that needs further bracing to prevent deflection.
Sort of like a bridge truss, to maintain rigidity of an otherwise lightweight and thin structure.
And of course weight=money, and so you want to minimize the net weight of all castings, while maintaining the required strength.

Sort of like the ribs on top of a steamer trunk, to its top from being crushed under the weight of trunks stacked on top of it.
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5th engraving down shows a piston valve with outside admission, and a valve chamber flush with the cylinder head.

2nd to last engraving shows a piston valve, with the valve chamber protruding significantly beyond the end of the cylinder.
I can't difinitively state whether this engine is inside or outside admission.

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Looks great

Dave

 

[GreenTwin]

Jason, very nice engines.
I made a flywheel for my dad's Scientific American, but have never run it, and have not disassembled it either.

But the question is "How does the rocking valve work on the two-cylinder Westinghouse engine ?".

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[Jasonb]

I would assume the rocking valve has two "passage" offset at the required angle so that while one piston is open to the inlet steam the other is open to exhaust. As they are single acting engines the valve is a bit simpler than I showed which is the double acting one for the Filer & Stowe. For a single acting engine the valve spindle just needs a flat machined into it, two in the case of the 2 cylinder Westinghouse engine.

 

[Jasonb]

this sort of thing

https://fineartamerica.com/featured...ent-drawing-from-1885-vintage-aged-pixel.html

 

[GreenTwin]

That is a great image, and with a Stephenson's link no less.
Just when you think you have seen it all................

Is the exhause passage in the center of the valve, or are there passages cast into the block ?

This is a Westinghouse style I could get into building.
I am just not keen on making or maintaining piston valves and their associated sleeves.

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[GreenTwin]

Here is the engine we are discussing.
It has a patent, so this is public information that anyone can download from the patent office; no copyright.
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[Jasonb]

Steam in the top. Plenty of detail on the patent

https://patents.google.com/patent/US329954A/en

 

[GreenTwin]

Great stuff, thanks much.
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[GreenTwin]

Patent drawings from Jasons' link:

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[GreenTwin]

I would consider this not a typical rocking valve, since it apparently does not float like a Corliss valve, but rather is fixed in a cylinder.
So this valve would not self-adjust as it wears.
Very clever design though.
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[GreenTwin]

Here are the only bottle engine designs I have seen with rocking valves.
I don't know whose photos these are.

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