What are the relatively new anti-loose measures for bolts and nuts?
1. In the earliest days, there will be some simple anti-loose methods. For example, after the bolts and nuts are installed, they are screwed into the back of a nut. Because the two nuts are loose, the torque is different. 2. In the early days, some more violent means will be used. For example, after the installation, the bolts and nuts are combined with the threads of the back part, which can't be loosened, but they can't be taken down. 3. Later, some filler locks appeared. Some elastic materials such as rubber and nylon were filled in the threaded parts of the bolts or nuts. When installing, the tightening torque was used to force the filler to deform, due to the elasticity of the filler. Anti-loose reliability is improved; 4. There is also a mounting part that is not very strict in anti-loose requirements. It is glued to prevent loosening. It is also well understood. After installation, use nuts and bolts with strong glue. Sticking; 5. Relying on foreign materials to prevent looseness, just like the nut + spring pad + stop pad mentioned in the question. Another similar application is the wider way to prevent pinning.