Research On Characteristics Of Flow Of The Internal-curved Planetary Gear Pump

The Internal-curved planetary gear pump is a kind of variable capacity hydraulic pump which possess the non-circular planetary gear transmission. In internal-curved planetary gear pump, the non-circular center wheel meshes with the planetary externally, and the planetary meshes with the non-circular internal-curved gear ring internally. The center shaft’s rotating, which drives the planetary gear rotation and revolution, resulting in seal change of the volume space cycle, in order to absorb or discharge the liquid. Because of large volume change per unit of time, when it is used in the hydraulic pump, the discharge of liquid volume is large too. This structure brings low pollution sensitivity for the fluid, low noise, simple structure resulting in long service life. In the structure of internal-curved planet gear pump’s planetary wheels are distributed symmetrically, each inlet, outlet holes with respect to each planet gear also symmetrical distribution, further the balance of the radial hydraulic pressure, radial force greatly reduced by making the center wheel, planetary gear, the internal-curved gear ring symmetrically, shaft of the pump and bearing the load are greatly reduced accordingly, so that the pump has better mechanical property, and created the condition of the high-pressure for the pump.This paper first introduces the internal-curved planet gear pump’s structure. Then analysis the status level of domestic and international and the research significance.Secondly, build the motion relationship of the internal-curved planet gear pump according to the movement of the central wheel and the internal-curved gear ring Design the pitch curve of the center wheel and the internal-curve gear ring through the relationship. Then according to the condition equation, using the Matlab programming to simulate of noncircular planetary gear pitch curve. Build the three-dimensional structure model of internal-curved planet gear pump.Third, Make use of the46type of the internal-curved gear pump as an example,through the simplified model, adopt the pitch curve’s section to research the flow characteristics of the pump. Analyzes the minimum and maximum cross-sections of the pump, the capacity of the pump and discuss the fluctuating rate of the pump.Finally, according to the structure of the internal-curved gear ring, research the characteristics of the formation law of the flow holes, the size of the flow holes location, number and provides a design of device of the flow plate.