Scroll profiles in scroll compressors: General criteria and error sensitivity

General criteria for scroll profiles that include the evolute, orbiting movement, differential, and integrative conditions are proposed. The profile error sensitivity is defined based on the composite meshing error and meshing clearances of the scroll profiles. A case study on regular polygon involutes as scroll profiles indicates that the general criteria are satisfied when the edge number of the two involutes of a regular polygon is equal to the common multiple of the doubled number of scroll wraps on one scroll. The profile error sensitivity of the involutes of a base circle is shown to be controlled by the radial machining error, which is extremely low. The involute of a base circle is the ideal profile for a scroll compressor because it contains low error sensitivity and more stable dynamic characteristics.