Does anyone know the patent status of the Wankel-type rotary engine?

[headintheclouds]

Can anyone start producing rotary engines, or would they likely have to be licensed by companies like Mazda, Wankel, Moller, or others?

Are certain critical technologies are still under active patents by Wankel or Mazda or ...?

 

[EngJW]

Back around 1987 when I worked on a rotary program, there actually was a Wankel company in Germany that probably held the patents. If not, if would have been NSU. Felix Wankel himself passed on several years ago. Curtiss Wright held the original license for the US and everyone else had to go through them. Since it is now past the 17 years patent rights time, the situation may have changed.

Chances are, few people would have the resources to produce a complete engine on their own. Since they would have to borrow from others, they would likely run into patent and licensing issues. There were many other patents besides the original concept.

 

[jejtopgun]

From what I have heard the original patent is now in the hands of mazda. However, a large amount of new patents, special around the rotor sealings have been made in the last few years. I know a company in Germany that is trying to produce a diesel rotary engine. Maybe worth takling to them. I will find out the name again and put it on this forum.

 

[headintheclouds]

jejtopgun,

I am very interested in learning about the German company working on a diesel version.

Thanks in advance for any info.

 

[GregLocock]

I bet they're up to their necks in hot water.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[headintheclouds]

Ok it's time for me to ask this question:

From my little bit of USPTO searching and from someone else in another unrelated forum who says he has searched, saved and studied hundreds of rotary engine related patents- well, it seems to me that the only hold anyone has of anything related to the rotary engine are those with particular technologies, for instance like rotor seals which may be, but likely are not, showstoppers (there is rarely only one way to skin a cat). I am told that Mazda has not bothered to patent much lately, and that the vast majority of the original patents are long expired without any kind of "renewal".
So it would seem to me that the field is open.

Can anyone inform me otherwise? If so I would be pleased to learn in order to not waste my time and work.

I am arranging to do serious patent research, but that is not a mere couple hours or couple days of work, and I am "innocent" as regards patent laws and practice.

 

[DesignOutsourcing]

Keep us posted headintheclouds as a diesel rotary sounds like a great aero engine. Ther are lots of leads if you search diesel wankel on google.
cheers, derek

Join us at

http://groups.yahoo.com/group/opensourcecars

 

[tbuelna]

headintheclouds,

Wankle in Germany claims they are developing a heavy fuel rotary:

http://www.wankel-ag.de/entw_e.html

RPI (Rotary Power International) was also trying to market a spark-assist heavy fuel rotary for several years, but they went out of business.

The drawback with these spark-assist heavy fuel engines is that they are usually fairly low performance (regardless of what their developers like to "project" or "estimate" about their power and fuel consumption).

Regards,
Terry

 

[magnograil]

Midwest engines has a couple versions running on JP4/8(?). ITT was using one in an evaluation test for drone use. This is a development of the BSA/Norton rotary after they went out of business.
I do not know if the Midwest JP engines are spark or glow ignition. They were still making a aviation gasoline version for light aircraft last I looked.

 

[headintheclouds]

To tell the truth, I am interested only in the diesel cycle and not just heavy fuel because of the results of the DA42 crossing the Atlantic. That event, I believe, is a watershed event that means everything is different now. The fuel specifics of those Thielerts mean a different future for GA propulsion - until turbine or other more advanced propulsion concepts overtake Otto or diesel cycle engines - which I don't see for at least 10 or 15 years.

 

[amorrison]

Info. on the DA42 Atlantic Ocean crossing here

http://www.diamondair.com/contentc/prTwinAtlan.htm