A New Gerotor Design Method With Switch Angle Assignability

Gerotor is generated by an oval shape generating curve which is attached to a large pitch circle rolling on an inside smaller one. For gerotor design, existing methods are able to handle arc-based generating curves with switch angle assignability. However, when dealing with non-arc-based generating curves, the current technology does not provide switch angle assignability. The switch angle is an important parameter in gerotor kinematics; it determines the angular conjugating range on the generating curve. In this paper, we developed a Deviation-Function (DF) based design method. By using this method, users can design and directly assign switch angles to both arc- and non-arc-based gerotors. Analytical formulations of both generating and gerotor profiles are derived and summarized into detailed algorithm in design steps. Some newly designed gerotor examples by using our method are provided for design and process illustration.Copyright © 2007 by ASME