After the paper is published, you will contribute your research results to the society for free. Anyone who sees the content of your paper will use this technology to gain economic benefits. Although your technology has contributed a lot, you can't defend your rights (because you have no right to maintain it).

The birth of patent is to avoid this situation and encourage inventors' inventions and their contributions to society. When the technical designer holds the patent right himself, anyone who wants to implement it must obtain the consent of the patentee, otherwise he can sue for infringement.