Study On The Theory And Simulation Of Cycloidal Pump

A novel meshing theory of gears used in internal cycloidal pump is studied. With complex vector mathematical tool, the equations of profiles of both external and internal cycloidal gears for this kind of pump are developed. Also developed are mathematical models of displacement, instantaneous flow rate, and fluctuation of flow rate. In addition, based on those models dynamic simulations are done, and meshing limited point, meshing angle and its relationship with rotary position of rotor are analyzed. Optimization is also an important aspect in this paper where pump displacement is taken as an objective function with variables generate index and arc radius index,and the constraints cover pump load, strength of pump components.A new idea called singular cycloidal tooth profile is proposed. For deep research into this subject, an optimization model for this type of pump is developed. In the model again pump displacement is taken as an objective function and variables are pump parameters. The constraints become continuous transmission and sealing performance of pump.Internal cycloidal gear with multiple tooth difference is researched where formulae are given for calculations of contact ratio, meshing angle, addendum and dedendum radii as well as rules of how to properly select those parameters. Furthermore, kinematic analysis, sliding coefficient, flow rate and fluctuation of flow of the pump is discussed. An attention to the tooth profile interference of the gears is also paid for the first time. Proposed are formulas of verifying tooth profile interference and optimization model for maximum pump displacement under the conditions such as minimum flow rate fluctuation and minimum gear wear.By MATLAB/Simulink package dynamic simulation models of the pumps are created, where dynamic performances of meshing point of gears and flow rate are carried out.Tooth-form modifications for internal cycloidal gear and internal cycloidal gear with multiple tooth difference are detailed. The method for the modifications is called rotary angle modification and its calculation algorithm is formalized.Methods of both calculation and measurement of the common normal length for internal cycloidal gear is developed.