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Invention:  Method for Sealing Cable Conduits   Patent No:  5,304,396

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Inventing a new Nozzle

I obtained from Mr. C  half a dozen sections of conduit and some more syringes, and got to work.  I tried all of the obvious things... changing the amount of time I injected the chemicals... changing the distance between the dams... using the better mixing elements... nothing would make the conduits leak proof.  Nothing seemed to work.

It appeared that the foam plug would shrink a little during the hour following the initial reaction as the plug cooled off (the foaming reaction creates a lot of heat and the plug gets pretty hot), letting water seep through the conduit between the conduit wall and the foam plug. 

I had to re-use the sections of conduit so I had to take the foam slugs out after each test.  I would ram them out with a long  2 x 4 stud.  After ramming out quite a few slugs, I noticed that they only adhered to a small portion of the though actually glued, but no adhesion occurred over most of the circumference of the plug/conduit interface. hmmmmm.

I tried sealing and testing another conduit, and paid close attention to which part of the conduit adhered to the was the bottom.

Ah Ha!  The only place the foam adhered to the conduit was where the un-foamed liquid came in contact with the conduit.  The adhesion occurred where the as yet un-foamed chemical formed a puddle. 

Inventing success!

I tried sealing another piece of conduit by not putting the front dam in place, squirting the fluid coming from the mixer nozzle all around the inside of the conduit making sure the un-foamed liquid formed a complete band around the inside of the conduit, and then quickly putting the front dam in place.

NO LEAKS!  I couldn't make the conduit leak no matter what I did!  I set it up vertically and filled it to the top with water.  A couple of weeks later it still had not leaked a drop.

Not only did the conduits not leak, but it was nearly impossible to the ram the foam plugs out of them.

Next I tried sealing the end of the nozzle and punching holes all the way around the tip of the nozzle with a sewing needle.  Now the nozzle would spray a radial ring of liquid around the inside of the conduit. 

A perfect seal every time!

Patent problems

Now Mr. C is a very charming man.  Initially he offered me not only 5 cents a nozzle, but also said that he would have his patent lawyer handle the patent which would be in my name. 

After demonstrating my new nozzle for Mr. C, he was so hot for them that he had me punching out nozzles by hand for him at $5.00 a nozzle so he could use them for sales demonstrations.  He was sending them all over the country as samples.

I kept telling him we had to get going with the patent because what he was doing amounted to public disclosure of the invention and the clock was ticking.  But there was always a reason why we couldn't start the process.  I finally got fed up and began the patent process with out him.  I was beginning to get the idea that he was a cheap bastard, excuse my language. It turned out to be much worse than that.

In the meantime he was desperate for large numbers of nozzles an asked me if I could build a machine to make them.  I built a machine that when a nozzle was inserted it would seal the hole in the end of the nozzle and simultaneously punched 12 holes around the circumference of the nozzle near the tip.  A person could punch about 15 to 20 nozzles a minute.

Invention royalty problems 

After I sold him the nozzle punching machine it suddenly became quite difficult to reach Mr. C.  Soon he was telling people that it was his idea to punch the holes in the nozzle and he had just told me to do that.  He refused to pay me the royalties.

I and several other vendors got together and sued him.  By the time we got to trial he had sold his business to a much larger firm.  We won the trial but the company that bought his company was suing for fraud or something and he finally declared bankruptcy.

We ended up with nothing.  Any body interested in a used nozzle punching machine?

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