I'm not in the industry, but I have had some experience with inventions. Here's the story for you and I hope it sheds some light on what NOT to do.
About 8 or 9 years ago, I came up with a little gizmo that facilitated adjusting fixed (dove tailed) sights on almost any handgun. Built a prototype, tested it extensively and worked a few bugs out of it. I also showed it to a few gunsmith friends of mine and they used it and liked it, because you could adjust the sights on the weapon without the use of a vice or hammer and puches.
Anyway, I ran across one of those companies that will test, patent and market your idea. They also they would do a patent search etc. etc. I gave them the drawings, a prototype and $500. I got a real nifty report back saying there was no such thing in the patent books and their engineers loved it and couldn't find anything wrong with the design. The cost for them to continue the process was $10,000. That money would garner me 30% of the profit on any sold item. Basically, every $5000 bought me another 15% increase in the profit taking.
Needless to say, I didn't have even a fraction of the necessary money, so I got my stuff back from them. About 2 years later, while leafing through an American Rifleman Issue, there was an add for the very item that I designed and built. NOTHING was different about it and somebody else was cashing in on my idea.
Later, I found out, that you have 12 months after making a design public, to patent or copy right it. Long story short, it would be wise of you to contact a patent attorney and find out exactly what you need to do. There are a lot of resources online that may be able to help. Basically, cover your a$$ on every front and get solid legal advice. It may cost you in the short run, but if your idea is worthy, it will pay you back ten fold.
Sabre