The Bucket Foundry

[WilDun]

Will the ring suffer gas sealing issues as the ring is being pushed to opposite sides of the ring groove as the ball moves? Or will the gas pressure overcome this as the ball slows to a stop?

I dunno, but I say that so long as the pressure is undernearh the ring at the critical moment that it will force it upward. (downward? - whatever) Reckon it might be better if the ring could rotate in the groove, - (I guess).
Trouble is as I see it, with this scheme the valve is being accelerated and decelerated and brought to a halt twice per crank revolution and at around 10 - 12 thousand rpm .......... well! depends on whether its for racing or something else more sedate.

[Grumph]

Over the years there's been a heap of rotary valve 4 strokes, from Aspin on. All shapes, journal type to cone shaped. Don't ever remember reading about a ball shape.
4 stroke can be quite easy as it's at 1/2 engine speed...2T would be somewhat harder.
Personally, I'd stay away from oscillating valves, it's easier to keep something moving, even against combustion pressure than start it against the same pressure.
Wouldn't surprise me if someone does bring back the 4T rotary valve - but as has been suggested, in ceramics.

[WilDun]

As an aside, the scientists and aviation experts of the day (in America) said that the model A Ford engine would not be any use in an aircraft.
Then Pietenpol built his Aircamper homebuilt using a model A and it flew well. (and it's still being built and flown today).
When Pietenpol was asked by the press about the expert opinions, he said that if he had only been told that it was impossible, he would never have built it!

[Flettner]

As an aside, the scientists and aviation experts of the day (in America) said that the model A Ford engine would not be any use in an aircraft.
Then Pientpol built his Aircamper homebuilt using a model A and it flew well. (and it's still being built and flown today).
When Pietenpol was asked by the press about the expert opinions he said that if he had only been told that it was impossible, he would never have built it!

[Flettner]

Pistons stop and start twice per crank rev.

[Yow Ling]

if you ceramic coated the bore of the valve so there was less heat transfer to the ball that might help at the cost of heating the return pulse, could you put water passages in the ball ? where would the gesparking plug live?

Anything is possible, can even put metal in the microwave these days

[WilDun]

Pistons stop and start twice per crank rev.

Yes isn't that enough?!!!

Have a good look at the old LeRhone WW1 rotary radial in which the crank stayed still and the cylinders rotated - you immediately think of pistons accelerating, decelerating and stopping, - NOT SO , if you trace the paths of each individual component you will see that they all move in a circular path (but on different axes) and the only reciprocation taking place is "relative reciprocation", ie relative to each other. only problem with this system, the exhaust sprays its contents everywhere including castor oil! and of course there's the flywheel effect! - can't have everything I guess!

[WilDun]

Wait a minute! this is the foundry thread - isn't it?
Got to head off, going away till sometime tomorrow, good discussion!

[Flettner]

if you ceramic coated the bore of the valve so there was less heat transfer to the ball that might help at the cost of heating the return pulse, could you put water passages in the ball ? where would the gesparking plug live?

Anything is possible, can even put metal in the microwave these days

The valve is hollow, for cooling fluid to run through , perhaps I just try it and see. Best to cast a valve in LM13 I think to minimise expansion.

[husaberg]

Over the years there's been a heap of rotary valve 4 strokes, from Aspin on. All shapes, journal type to cone shaped. Don't ever remember reading about a ball shape.
4 stroke can be quite easy as it's at 1/2 engine speed...2T would be somewhat harder.
Personally, I'd stay away from oscillating valves, it's easier to keep something moving, even against combustion pressure than start it against the same pressure.
Wouldn't surprise me if someone does bring back the 4T rotary valve - but as has been suggested, in ceramics.

Aussie bloke did a Round ball with piston rings in the 70's I have the article here somewhere.
went fine I guess he had the same problem as the rest lubrication or smoke but not one without the other.
He converted a Honda single and an old brit banger. Could run very high comp ratio. I think it was meant to be very quite with is counter intuitive....... faded away.....

[husaberg]

Yes Husaberg will find it.
Will the ring suffer gas sealing issues as the ring is being pushed to opposite sides of the ring groove as the ball moves? Or will the gas pressure overcome this as the ball slows to a stop?

Like I say, suck it and see,but I'm a great believer in continuously rotating (one kind of rotary engine or another) etc. - this stopping and starting business is something that needs to be overcome! turbines are the way to go on aircraft -but the throttle lag stops them being used on anything else except as generators on hybrid setups - just my opinion
No, I can't find any memories of ball valve exhausts in two strokes, but I do remember a couple of Aussie guys experimenting with a similar arrangement (but rotating) around 35 odd years ago on a Honda 100, but it quietly departed the scene after a year or so, however, if you could find this you might be interested, they must have gathered some good info in the process!
Don't think i've got it in my old scrapbooks, but maybe Husa has the photos somewhere!

I started on the last page. so I am type cast.
It is an a two wheels mag.(pretty sure)

[Flettner]

if you ceramic coated the bore of the valve so there was less heat transfer to the ball that might help at the cost of heating the return pulse, could you put water passages in the ball ? where would the gesparking plug live?

Anything is possible, can even put metal in the microwave these days

Spark plug could be inset into the ball ( surface fire type as I'm using in my F9 Kawasaki ), then it would appear in the centre of the chamber and by way of the ball shape be near to the piston, a bit like the toridal (?) type head.
Imagine having a clean cylinder with just transfer ports, exhaust out through the head, uniflow scavenge. And no bloody valve heads in the way!

[husaberg]

Spark plug could be inset into the ball ( surface fire type as I'm using in my F9 Kawasaki ), then it would appear in the centre of the chamber and by way of the ball shape be near to the piston, a bit like the toridal (?) type head.
Imagine having a clean cylinder with just transfer ports, exhaust out through the head, uniflow scavenge. And no bloody valve heads in the way!

Can't find article but here it is anyway
http://79x100.blogspot.co.nz/2012/12...prototype.html





I have posted this before its been nearly ready since the early 90's





http://www.thetruthaboutcars.com/200...ounting-begin/

[Flettner]

Can't find article but here it is anyway
http://79x100.blogspot.co.nz/2012/12...prototype.html

Thank you, you should not be allowed to leave the country, you are a national treasure sir!

[husaberg]

Thank you, you should not be allowed to leave the country, you are a national treasure sir!

Good to know I do have you uses.
I added the patent as well..in true anorak style, Funny enough there was talk of a court order to stop me entering some countries