The design scheme of machine product can be newly explained by applying the black box theory, this design pattern is a combination of functional and structure design method. The method was finally expanded into black box theory and gray box theory. With the help of black box-gray box theory, the design outlines were made, the transform elements of mechanism were programmed, and then the technical process and functional structure of machine were realized. The black box graph, the grayed black box graph, and gray box graph were used to describe the design process in sequence. The scheme design was changed to be a gradually improved process. If the design methods of black box-gray box theory were deepened, the next system design can be called the design of the white box which was the concrete implementation of scheme design. In this work, the black box-gray box theories were successfully applied to investigate the machine design scheme for the projection model of customer’s requirements.