Recently I dreamed up a configration for a two stroke engine that eliminates the need to add oil to the fuel and the inefficiency that comes from losing unburnt fuel out the exhaust. Has anyone else managed to do this yet? If this does turn out to be something potentially profitable what then?
You mean, I’m guessing, it uses valves, a supercharger, and improved oil journaling and spray system like a conventional 4-stroke? Could it be similar in design to an Orbital 2-Stroke engine?
No, nothing like that. It only has a few more parts than a normal two stroke.
Patent it before you talk too much about it.
I’ve been peripherally involved in a couple of new engine designs (my firm did some objective analysis and documentation), and while I can’t say anything about your design, I can say that you have a long road in front of you.
Thin Ice is probably right about the patent, but there are lots of people who think they’re pretty useless for individuals. Search for patent-related threads on this forum for those views.
You need a solid design, some analysis which bears out your notions of how well it will work, and then a prototype which can demonstrate its effectiveness. However, even if you get a prototype which proves your design is a superstar, realize that outperforming the competition is not sufficient to gain market share. Current engine designs are entrenched because they have mass-production, spare parts, qualified repairment and familiarity on their side. Your design will have to be not just better but so much better (by orders of magnitude, not fractions) that you can overcome the market momentum of the existing designs. As any inventor will tell you, the best product does not win the market. The market goes to people who know how to market.
I don’t mean to be pessimistic, but I’ve seen a couple of these designs before. The ones I’m familiar with were better than existing designs and solved real problems, but they weren’t spectacular enough to gain attention. In one case, the design was just incrementally better than existing designs and was radical enough that no one would pay much attention outside the novelty aspect. The inventor pushed it for years, spending enormous resources, ultimately for nothing but a patent certificate and a few human-interest stories in local newspapers.
It’s already being done.
http://www.orbeng.com.au/orbital/home/home.htm
Its a a 2 stage injected 2 stroke.
Air is first compressed by a pump driven from the crank, this replaces the use of the crankcase to achieve first stage compression in conventional 2 strokes, and means that the main bearings can run in their own lub oil without being washed with fuel, it also means that the fuel does not have to burn the lubricant in the combustion process, which makes for much greater engine longevity and a much cleaner emission.
The pressurised air is fed to a mixture chamber where it is metered in and mixed with fuel fired from an injector.
This mixture is then fed into the combustion chamber.
All this can be timed so that there the outlet port is fully closed, instead of in a conventional 2-stroke where both inlet and outlet are open at the same time, which results in unburnt fuel escaping at the less optimum engine revs.
It allows the exhaust to be tuned very differantly since it now no longer has to provide the pack pressure to keep the fuel/air mixture in and yet scavenge the burnt gases from the cylinder.
The result is that the injection process can be timed to the optimum at all engine speeds, instead of the typical and very marked power band in most 2-stroke engines.
In high power 2-stroke engines there is usually a limit in terms of practicality which tends to mean that they are rarely more than 500cc for motorcycles, the system of reed valve or spinning valves gets complex and starts to sap power and efficiency, but in this engine that limit doesn’t apply.
Aprilia are using this engine on one of their scooters, but it turns out that at larger capacities say of 1000cc, you get a cleaner engine than a 4 stroke, better efficiency and a lot more power, I have seen reports that well over 300 bhp is easli possible, the limitation for bikes being the requirement for that much power and the chassis and tyre technology to go along with it.
It holds a lot of promise but apart from the scooters, other machines have not been made in consumable numbers, but this could well be because of a large decline in the Euro scooter market which is starving the major manufacturers of cash.
There is always room for more ideas, such as rotating disc valves on 4-strokes, or varible rate con rods, develop yours and you might find backers.
Mine is less complex than the desgn mentioned, does not adically change the basic design, and can achieve the same effect. (pardon my obfuscation) Assuming I can make a small working model would I be better off leasing the design to someone else with the resources to push it through or perhaps marketing it as a model plane engine?
First thing to do is a patent search, to see if anyone has done this.
http://www.uspto.gov/ - this is the US patent office, I think you need special software to print anything off it.
Here’s a cool little site with nice animated engine diagrams. Just the basics, but well done and quick to load:
http://www.keveney.com/Engines.html
Up to now I have been doing a lot of online research on different engine types because such things interest me, and so far it seems no one has hit upon this particular configuration. I confess that I’ve hesitated to search the patent sites due to the intimidatingly database.
hrm… after you have successfully designed a prototype, you market your engine to manufactures.
you don’t go out and make your own engines, unless you are into racing.
all inventors that i know of in the auto industry all target companies such as ford, gm, etc.
you get them to license your product.
good luck!
Thanks, the patent search is going a bit slow as I’m having a bit of trouble narrowing the search parameters properly.