Generally, three-dimensional software such as SolidWorks, Nx ug, proe, etc. is used to draw the three-dimensional model, and then the two-dimensional line drawing for patent is exported, and then flat software such as CAD, cdr, ai and other software are used to make the lines. Optimize and add hatching. If you still don’t understand, you can search on Baidu: Changning Changqi. Their company specializes in drawing patent drawings. I hope they can help you