The machine is the organic system which consists of many parts. All parts act cooperating one another, transferring and changing the energy according to their specific rolls, and as the result of their dynamic collaborations, the machine fulfills its mission as the required performance. The authors introduced a new approach on modeling and proposed the concept of the functional model in the previous report, in order to explain these rolls of parts as the functions. It is indispensable for computer aided development of machines in actual maker companies to construct the virtual product with which connecting parts from small scale to large scale units, assembling the machine from parts to total product, exchanging parts and disassembling the machine have to be performed easily by simulation in the computer. As the means to make this possible, a method for expansion and unification of the functional model is presented in this report. This method is shaped up with three examples.