Abstract: On the basis of the concept of characteristic spherical four-bar linkages, all spherical four-bar linkages can be classified into three classes, and the space models of spherical four-bar linkages can also be established. Every space model can be divided into several regions. Each region is equivalent to a group of spherical four-bar linkages. With the help of the method given by this paper, we can discuss the dimensional types and plot the character diagrams, with which we can design spherical four-bar linkages conveniently, of spherical four-bar linkages in a series of closed planes subregions.

Key words: Dimensional type, Space model, Spherical linkage