How long does a patent last?

[Raggi_Thor]

I have tried to ask the Norwegian designer Mr Birger Kullmann about this (www.kullmann.no) but he didn't answer.

In 1997 he (Kullmann) registered a patent for his rudder design, calld Vario-rudder. It's a retractable rudder in a rotating disk, hard to beleive he is the first, but nevermind that..

See http://www.google.com/patents?id=EJkfAAAAEBAJ&dq

Now I see that Hunter 216 has a very simmilar rudder.
http://www.huntermarine.com/Models/216/216Gallery.html

Does this mean that after 10 years the patent has expired?

[Raggi_Thor]

Just found this at http://www.huntermarine.com/Models/216/216Index.html

"The special hydraulic lift mechanism allows for effortless lifting of the lead keel, while the unique lifting VARA™ inboard rudder
delivers real performance with true beaching ability. Super easy to rig and launch!"

And this at Kullmann's web:

"VarioRudder™ (KullmannRudder)
...
NOTE: The "RUDDER DEVICE" is patented in a number of countries and a lisence for such a system must be obtained from Birger Kullmann or agents."

[Wynand N]

Originally Posted by Raggi_Thor

NOTE: The "RUDDER DEVICE" is patented in a number of countries and a lisence for such a system must be obtained from Birger Kullmann or agents."

check if it is registered in your country, if not, patent your version of it, period.

It is usually very expensive to patent something "worldwide" unless the product is of such that warrants such expense.
However, one usually identify target markets and patent there to protect you. Ever wondered why there are so many Chinese copies around of basically everything?

[Trevlyns]

I found this reference through Ask.com (the new Google!!)

Q. How long does patent protection last? (As of year 2005)
From Mary Bellis,
Your Guide to Inventors.

A. Utility and plant patents are granted for a term which begins with the date of the grant and usually ends 20 years from the date the applications were filed. You must make the timely payment of the appropriate maintenance fees.

Design patents last 14 years from the date you are granted the patent. No maintenance fees are required for design patents.

Here is the actual reference: http://inventors.about.com/od/invent...ction_last.htm

[Raggi_Thor]

Thanks, Trev and Wynand,

I got an answer from Mr Kullmann later today,
the rudder is patented in US and Norway and some other places,
and it's still valid.
The license fee for using it will be very reasonable, he writes.

Then the question is if Hunter Boats' VARA rudder is a violation of Kullmann's patented VARIO rudder :-)

btw: The patent is owned by KVAERNER, they financed the patenting process and planned to use it in ships.

[Bergalia]

Trev and Wyand pretty much cover it, Raggi. Came on this problem myself some years back when I 'invented' a clutch for a creel winch. After a six months wait the UK Patents Office sent me a sheaf of papers which would have served as an emergency anchor. Patents' costs (the traditional arm and a leg) and longevity vary from country to country and must be renewed virtually on the hour or they lapse. It was also pointed out that even a small variation (perhaps even just material used) can overcome the copyright. The only way to completely safeguard your invention is to take out a 'world-wide' patent (costing both kidneys and your heart)

[Raggi_Thor]

OK :-)
So Hunter is probably safe, just because they changed it a little?

[Bergalia]

It would seem so Raggi.Unfortunately now-a-days little seems protected by law except 'intellectual property'

[Raggi_Thor]

Do you see any difference?
The VARA rudder can be moved fore and aft...
Is that it?

[Bergalia]

Originally Posted by Raggi_Thor

Do you see any difference?
The VARA rudder can be moved fore and aft...
Is that it?

Raggi I notice that Kullman discontinued his patent rights in 1995. The Vara patent is 'registered' in 1996. Perhaps this is the reason for the 'similarity' in design.

[Raggi_Thor]

Kullman sold his patent to Kvaerner, it's still valid, he sais.
It's a strange business, I asked Kullmann because I didn't want to do anything illegal, but now I don't see the difference between the two patents. If I just make a lifting rudder in a rotating cylinder, I'll probably get sued by both of them :-)

Forgot to say, Mull is of course on my list for future cruises, after the Caledonian canal!

[Bergalia]

I see your problem Raggi. Do you intend to fit rudder to a series of boats for the commercial market - or just a one-off. If a one-off, either don't mention the 'patent' confusion - or give credit saying 'a modified version of so-and-so's' patent lifting rudder.
If for a full-run commercial series then I think you'll have to invest in a time-served patent lawyer to be on the safe side. Sorry I can't be more definate.
That aside, when you cruise the Caledonian Canal (great scenery through the lochs by the way) start your trip with a visit to the Gellans Bar in Inverness. It's in the High Street opposite the Town House - but any 'native' will direct you. Don't be put off by the small 'front' - the bar opens up once inside.

[PI Design]

I think if its just for personal use you are entitled to ignore any patents.
But my understanding is that you don't need to change things very much to get round most patents anyway. Kvaener are surly more interested in big ships?
I'm quite suprised it is patented though, 'cos I have been considering a rudder like this for some time, and I'm sure I got the idea from someone else.

Cheerio.

PS Bring insect repellent if your going to cruise in Scotland!

[Raggi_Thor]

Thanks, am used to mosquitos :-)

[Bergalia]

Originally Posted by Raggi_Thor

Thanks, am used to mosquitos :-)

Mosquitos Raggi. Pah, amateurs.PI Design is referring to the West Coast 'midge'. If you haven't met them todate - as Al Jolson said in 'The Jazz Singer' - "You ain't seen nuthin yet...."