Author Topic: Double acting Double cylinder Oscillator  (Read 30257 times)

Offline Brian Rupnow

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Re: Double acting Double cylinder Oscillator
« Reply #180 on: June 14, 2018, 03:42:45 PM »
As promised, here is the final video of the double cylinder oscillating engine. Please note that I misspoke in the voice-over and said it has a 2 3/4" stroke. That was wrong.--It has a 1 3/4" stroke.---Brian
<a href="https://www.youtube.com/watch?v=1id_-5Ahbo4" target="_blank">http://www.youtube.com/watch?v=1id_-5Ahbo4</a>
« Last Edit: June 14, 2018, 06:32:08 PM by Brian Rupnow »

Offline Brian Rupnow

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Re: Double acting Double cylinder Oscillator
« Reply #181 on: June 14, 2018, 04:39:07 PM »
Is there a "tried and true" method of making a simple air reversing valve. On my current engine I have two "out" ports which the exhaust comes out of, and two "in" ports where the air pressure goes in. My intake manifold feeds air to the top two ports and allows the bottom two ports to exhaust to atmosphere. I was laying in bed last night thinking about a "reversing handle" on the manifold which would allow me to reverse the engine direction. I have it designed in my head, but it is a bit crude. If a current design exists for this, I would happily copy it.
« Last Edit: June 14, 2018, 06:38:16 PM by Brian Rupnow »

Offline sbwhart

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Re: Double acting Double cylinder Oscillator
« Reply #182 on: June 14, 2018, 06:40:17 PM »
Very smooth runner and nice and slow Brian very nice engine indeed. Are the port caves running together both ally. I have some drawings of a reversing valves for engines that I’ve made if you want i can mail them

Stew
A little bit of clearance never got in the way

Offline Brian Rupnow

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Re: Double acting Double cylinder Oscillator
« Reply #183 on: June 14, 2018, 06:47:43 PM »
Stew--I would appreciate that.--Brian If you send the plan snail mail, my address is 1095 Carson Road, springwater, Ontario L9X0V4

Offline Brian Rupnow

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Re: Double acting Double cylinder Oscillator
« Reply #184 on: June 14, 2018, 08:53:11 PM »
Very smooth runner and nice and slow Brian very nice engine indeed. Are the port caves running together both ally. I have some drawings of a reversing valves for engines that I’ve made if you want i can mail them

Stew

Stew--Not sure what you mean by "port caves". The frame is aluminum and has port passsages drilled in it. The rocking cylinders are cast iron and have the mating ports drilled in them, in typical wobbler fashion.---Brian

Offline Brian Rupnow

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Re: Double acting Double cylinder Oscillator
« Reply #185 on: June 14, 2018, 09:37:29 PM »
Now we're going to engage in a little foolery here. The part shown is part #1 of a theoretical reversing valve. All you really need to know is that with an oscillating engine, if you put air in port "A" and let the air go thru the engine and come out port "B" the engine will revolve clockwise. However, if you put the air in thru port "B" and let it run thru the engine and out port "A", the engine will revolve counter-clockwise. The third hole with no designation is going to be a pivot for a reversing lever.---Use your imagination---It helps.

Offline Brian Rupnow

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Re: Double acting Double cylinder Oscillator
« Reply #186 on: June 14, 2018, 10:02:16 PM »
So here we have the reversing lever in position #1. Air flows in the green inlet tube, up thru a passage in the lever, and out a hole in the far side of the lever which is lined up with port "A". Air flows in port "A", thru the engine, and out port "B".---Engine revolves clockwise.

Offline Brian Rupnow

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Re: Double acting Double cylinder Oscillator
« Reply #187 on: June 14, 2018, 10:05:47 PM »
In this picture, the reversing handle is at mid position. Air flows in thru green tube, up thru passage in handle, but can't flow out far side of handle because it is not lined up with port "A" or port "B'. Engine is stopped.

Offline Brian Rupnow

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Re: Double acting Double cylinder Oscillator
« Reply #188 on: June 14, 2018, 10:12:35 PM »
In this picture, the reversing lever has been swung over until it lines up with port "B". Air enters thru the green tube, up thru the internal passage in the handle, into port "B", then thru the engine and out port 'A", causing the engine to run counter-clockwise. Remember, that hole at the bottom of the lever is for a "pivot shaft".--There is no air flowing down towards the pivot, ever.

Offline Brian Rupnow

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Re: Double acting Double cylinder Oscillator
« Reply #189 on: June 14, 2018, 10:20:31 PM »
So---As I said earlier, I have an idea for a reversing valve, but it is crude. Even under the best of conditions it would be difficult to keep air from leaking like crazy, and it is crude having the airline running to the reversing lever. I know it would work.--However---None of this is "new" stuff. I am sure that somewhere over the last 200 years, a far superior and simpler design must have been made.  I am looking for that "simpler and superior" design now, and remember, it has to be something simple enough to be fabricated on a manual mill and lathe.---Brian

Offline NickG

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Re: Double acting Double cylinder Oscillator
« Reply #190 on: June 14, 2018, 11:09:55 PM »
I quite like that on Brian, easy to make. As you say the only issue could be
Sealing but with the surfaces lapped and if you can put a compression spring on the pivot it would have a decent chance. Probably only be a real issue in the engine stopped position. Getting more complicated but if you encapsulated it I.e. made something around the other side of the lever you could use a kind of lead spring to exert pressure right across whole lever rather than just where the pivot is.

Or, you could do something along the same lines with 2 discs. So when you rotate through that angle, holes in the discs line up for inlet / exhaust. If the pivot can be kept in the centre of the disc it would give you a better chance of sealing as the spring will exert a more even pressure.


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Offline Ramon Wilson

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Re: Double acting Double cylinder Oscillator
« Reply #191 on: June 14, 2018, 11:13:17 PM »

Not quite two hundred years Brian but here's one I did earlier - not rocket science and nothing magic just a bit of R/T work involved - no leaks at 30 - 40 psi




Works as you describe - one way to go one way, the other way to go the other and stops in the middle.

No drawings but the pic should be explanatory enough - inlet on one side, exhaust on the other top outlets to the engine (the two holes in the bottom are mounting holes) - as here...




Hope that's of use - Tug


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Offline Brian Rupnow

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Re: Double acting Double cylinder Oscillator
« Reply #192 on: June 14, 2018, 11:17:16 PM »
Ramon--that's great. thank you.---Brian

Offline Brian Rupnow

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Re: Double acting Double cylinder Oscillator
« Reply #193 on: June 15, 2018, 01:12:37 AM »
Ramon--I am trying to model this valve and figure out what the passages are in the bronze block. I wish I had x-ray eyes like Superman. Can you give me any hint as to what lines connect to which of the 4 visible ports? How far do you have to swing the handle to go from full clockwise to full counterclockwise. I am assuming that when the handle is straight up there is no steam passing at all and the engine is stopped.---Brian EDIT--EDIT--I think I got it. The ports going out to the cylinder are on the extreme right and extreme left on the face of the block. Air coming into the block comes out at the top port on the face of the block. Air exhausting from the block has it's port at the extreme bottom of the face on the block.  You would have to swing the handle 45 degrees either way from the vertical position to make the engine run clockwise or counterclockwise.---i think!!!

« Last Edit: June 15, 2018, 01:42:54 AM by Brian Rupnow »

Offline dparker

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Re: Double acting Double cylinder Oscillator
« Reply #194 on: June 15, 2018, 01:56:04 AM »
Brian:
There is a Elmer's Engine #3 that is OPEN COLUMN ENGINE with Reverse that may give you a switching valve idea that you could use to make your "GREAT" engine reversible.  Your modeling is very admirable and a joy to watch the whole process from idea to running engines.  Thank You for your contributions to us Model Engineering folks.
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