根据对应的节线类型把压缩腔分为a、b两类，定义涡旋压缩腔的宽度、长度和法面面积，用解析法建立以型线、压缩腔形状变化、生命周期和压缩腔数综合的涡旋压缩腔几何模型，分析压缩腔的宽度、长度、面积、体积、质心、啮合点的曲率半径等几何特性。研究表明：所建立的几何模型能真实反映压缩腔的形成、变形、破灭等过程，表征涡旋压缩腔的运动特征，可对压缩腔几何特性进行全面分析，是涡旋压缩腔几何学、运动学、动力学、热力学、仿真等研究以及设计的基础；Ⅲ类型线的压缩腔变化过于复杂，Ⅱ类型线的压缩腔变形及动力特性稳定，Ⅰ类型线的压缩腔变形效率高，加工相对容易，因此实践中宜采用以Ⅰ类型线为基础而中心啮合部分为Ⅱ类型线的组合型线。

The scroll compressor chambers are classified a-type and b-type by its types of pitch line, its length, width and normal area are defined. Using analytical method, the geometrical model that synthesized the profile, form, deformation, lifecycle and the living numbers of scroll compressor chambers is established. The geometric characteristics of scroll compressor chambers, such as length, width, area, volume, center of mass and curvature radius of mesh point are analyzed. The established geometrical model could demonstrate the forming, deforming and vanishing process, so all geometric characteristics of scroll compressor chambers can be overall analyzed which could serve as the foundations of scroll chmaber’s researches on geometry, kinematics, dynamics, thermodynamics, simulation and design. The changes for Ⅲ?type profile compressor chambers are too complex, the deformation and dynamics characteristics for Ⅱ?type profile compressor chambers are more steady, the deformation efficiency for Ⅰ?type profile compressor chambers is high and it is easy to machining. Consequently based on Ⅰ?type profile, the hybrid profile modified in centric meshing part by Ⅱ?type profile is well adopted in practice.