Patents won't protect you unless you take a violater to court. Will your patent be worth enough to go up against a major manufacturer? And if the design catches on, the Chinese will flood the market with ripoffs anyway.
If you do hook up with a good custom knifemaker, he will add a lot to your idea. It takes more than just a good-looking knife to get a manufacturer interested. It has to be adapted to the manufacturing process.
It is probably a good idea to make your idea known as of a certain time to establish precedence, if someone tries to say they came up with it themselves. But remember how many basic knife shapes there are, and realize -- people want those basic designs, and the rights are open for anyone to make them. It's how well they do it, and at what price, that makes them successful.