Clearance Space in Volumic Dimensioning

This paper presents a theoretical representation of the notion of clearance between two parts connected by prismatic surfaces. In order to characterize the clearance. the latter is associated to a fictive volume represented in a three-dimensional space. which is not the real space of the mechanical pans. The properties of the clearance volume are studied. An example is presented. A generalisation to the volumic case is considered. This method allows to develop a model that can be used from different points of view : computer aided functional tolerancing, manufacturing and control.