Doyle Rotary: Cylinder Block

Looking good. Enjoyed dropping by from time to time to watch the machining.

I may've missed it (I sometimes skip stuff in threads ), but what software did you use to design it & produce the CNC control programs? Apologies, and please just give me a link if you've already posted it somewhere.

Best regards.

I don't remember if I posted that information. We draw the 3D models in SolidWorks 2010 and program in SurfCAM Velocity 4. We use these programs everyday for the aircraft parts the business makes and just for fun.

Thanks.

The mech. designers where I contract (I'm a self-employed electronics type) use AutoCAD Inventor, which (when they put the correct dimensions in ) does a pretty good job for design & simulation/modelling.

They have a couple of nice old-ish Bridgeport mills, for which I've knocked up enough software to let them use a PC to save and re-load programs (laboriously keyed into the Heidenhain controller by Dan, who is sh1t-hot at translating a drawing into Bridgeport-speak), instead of the clapped-out tape drive they used to use.

I'm working on getting them to bridge the gap - to go from Inventor files directly to the machine. Save Dan a hell of a lot of time.

I've used Inventor but I like building assemblies more in Solidworks. For prototyping, assembly building is crucial and Solidworks is more consistent and quicker at it.

SurfCAM posts in many different codes so it might be able to post in the code your control uses. Our machines use G code (Centroid controls).

You'd have to import the Inventor files into SurfCAM (surfCAM supports many file types), program the NC operations and then post the program.

Way back I did a bit of Basic to convert 2D dxf files to G code for another company, who mostly just cut & pierced sheel metal. They were using punched tape at the time (giving my age away!).

The Heidenhains on the Bridgeports speak G code (or a variation of it), so SurfCAM will probably work. I'll look into it.

Thanks again,
John.

i just subscribed to this thread, but was there a previous one that explained what you are trying to accomplish??

if so how about posting a link to that...

thanks

The initial thread was a discussion about how the Doyle Rotary could be better than the conventional engine and contains links to some videos on youtube: New Engine Design: Doyle Rotary

The next thread was about viewing the live video of the cylinder block being machined: Live video of Doyle Rotary Being Machined If you follow the link you can watch the recorded videos. I will try to post any time that the live feed is active.

I've posted several videos on youtube describing the engine and I am currently working on a video that combines the previous videos (how the engine works) and that describes why we think the engine has the potential to be more efficient than the conventional engine. This video will include animations, pictures and a voice-over so its taking longer to make than the previous videos.

Dear Engine developer, designer, builder, etc.

This looks to my like its a sinkhole for money. How much have you and your father spent so far?

The chances that you sell that to a car company are essentially zero. Don't get me wrong, I do not want to talk you down, but a sale is next to impossible. If you want to succeed you would have to go into production and better build a utility vehicle or application for it at the same time. No one will break down your door to get to it.

That is a fact. I know, been there, done that. The OPOC engine might have a better change and these people have gotten Bill Gates to spent some money on it. See:

http://www.hybridcars.com/news/bill-gates-invests-better-internal-combustion-engine-28242.html

From a technical point of view, I do not think that the transfer of the gases will work. There have been other inventions along these lines to transfer the power medium form one space to another, and none has succeeded. How do you prevent back flow? Compression is usually lost anyway, too much volume in the transfer channel, at least that would be some of my concerns. Its shape is not very favorable either.

In reality, I am trying to help as much as I can by stating the above. I like inventors and tinkerers. But the principle has to be sound. This one is not in my opinion.

Take it as you will, as a warning or not. I have your well-being in mind by replying.

Regards,

Floram

Dear Sir.

That is an interesting reply. Thank you. Admittedly, when I referred to the shape as not being favorable I was not considering its displacement, as I simply did not know. If the numbers are as you say, displacement vs overall dimension, and I have no reason to doubt that, then this argument likely is not valid.

My key concern is the transfer of the working fluid. Looks like it is different as simply between two cylinders which has been tried before. I must have another look how it really works as you talk about Apex seal of Mazda used in the rotary that are applied.

Between two cylinders in a Reciprocating engine we do not have that situation and it must work differently. Suggestion where to find a good description, US patent No.?

I also wonder how the outer track and its rollers will stand up in time, speed, noise, wear, specific contact loads, lubrication etc. Cooling might also be a concern?

Sorry for the delayed response. My classes just started back up and we are also still working on a longer video that will describe how the engine works, why we think the engine is better and the structure of the engine.

Before we get started here I would like to point out that a new thread has been started for the machining of the cylinder retainers.

The flow of the working fluid through the engine will be illustrated in the big video (but because of classes, other priorities and learning how to make the video as we go, it might be 2-3 weeks before its finished). Because the video is so far away I will try to explain the flow step-by-step so that our discussion can continue here.

Intake and compression cylinders:

While the intake piston moves away from TDC to a little bit after BDC the cylinder is open to the intake runner. So air moves through the runner, then through the cylinder port and finally into the cylinder. After the cylinder port passes the apex seals that separate intake from compression, the air in the cylinder can not escape and the piston begins to compress it. The cylinder port opens to the combustion chamber as the cylinder approaches TDC. The compressed air flows from the cylinder into the combustion chamber.

Combustion chamber:

The steps within the combustion chamber are:
1. Compressed air enters
2. The combustion chamber is closed off to the compression cylinder
3. Fuel is injected
4. The spark plug is fired
5. The mixture is allowed to burn
6. The expanding air-fuel mixture travels into the power cylinder and applies pressure to the piston.
7. As the expanding air exits the combustion chamber, the pressure within the chamber decreases rapidly until the cycle begins again with compressed air traveling into the combustion chamber.

Power and Exhaust:

The power cylinder is open to the combustion chamber for 100 degrees. During this time the expanding gasses force the piston out. After the port closes, some pressure remains in the combustion chamber and some continues to do work within the power cylinder until the piston reaches BDC.

We reserve some pressure in the combustion chamber so that it is not wasted by applying pressure against the piston when the rod is at an inefficient angle. Instead, that residual pressure adds to the power of the next combustion cycle and is used for work when the rod is at a more efficient angle. The goal is to allow as little as possible pressure to escape the motor through the exhaust. (A side note: In a conventional engine no pressure can be stored so energy is wasted applying pressure when the rod is at a bad angle and a lot of pressure exits the cylinder when the exhaust valve opens.)

After the power piston reaches BDC, the cylinder port opens to the exhaust runner and the spent gasses exit the motor.

About the outer housing:

This video about the synchronizing drive rods kind of shows how the outer housing and cylinder block rotate around the crankshaft. The outer housing is supported by a plain sleeve bearing on each end. The cylinder block is also supported by two plain bearings. The cylinder block and outer housing are synchronized by the sync rods (orange in the video). The connecting rods attach to the outer housing with wrist-pins.

The plain bearings are oil-film bearings and will be extremely quiet and reliable as long as the oil pump supplies oil (just like the bearings that support the crankshaft of conventional engines).

Cooling:

The prototype will be oil-cooled. The oil is pumped through the crankshaft then around each cylinder and then finally out into the outer housing where it is scavenged and returned through a cooler to the dry sump tank.

Oil will also be pressure fed through the connecting rods to the bottom of the piston. This allows us to spray the bottom of each piston for cooling similar to how today's direct-injected engines cool the pistons.