A good next step would be to do a basic patent search. For this there are a couple of choices: The U.S. Patent and Trademark Office offers free searches. However, if you want to view or print out a complete patent with drawings and claims there is a nominal charge of a few dollars.
Think of the unique features of your invention. Then consider relevant keywords and short descriptive terms to describe it. You may be able to identify patents that could be relevant to your invention. Please bear in mind that if you need a thorough and complete patent search it’s advisable to employ the services of a patent attorney or a company that is specialized in this area.
One note of caution: Regardless of your web search or even a professional patent search it’s always possible that a similar invention is already in the planning stages somewhere. Someone may even have filed for a patent on a similar notion. But until the patent has been acted on by the patent office or published, it won’t show up in a search. Unfortunately, neither of these possibilities can be eliminated as a potential risk.