American "invention patents" include China's "utility model" and "invention patents". Therefore, functional innovation can be patented in the United States. China applied for a "utility model". If there is no similar patent in the United States, it is likely to apply for an "invention patent" in the United States.
Invention patents protect function and technology, so no matter how the appearance changes, as long as we use technology or methods to realize this function, it constitutes infringement. Invention patents have a wider scope of protection and greater rights and interests.
About applying for American patent, you can go to Gaowo to find out. Gaowo is a legal service organization specializing in intellectual property agency business, including Beijing Gaowo Law Firm and Beijing Gaowo International Intellectual Property Agency Co., Ltd., whose business mainly involves basic applications for trademarks, patents and copyrights and rights protection litigation. For more information, I suggest you consult Gao Wo.