The Development Of Design System For High Pressure Low Noise Helical Rotor Pump And Complicated Tool

As a kind of energy conversion device, the gear pump plays an irreplaceable role inthe national economy. With the development of society, the environmental protectionconsciousness and the concept of the energy crisis are becoming more and more strong.The problems of traditional gear pump, such as the low pressure, big flow ripple, largenoise and low efficiency, are becoming more and more serious. The invention of highpressure helical rotor pump in foreign countries provides a new direction ofdevelopment to the gear pump.The helical rotor pump not only inherits the advantage ofsimple structure from traditional gear pump, but also has characteristics of high pressure,small flow ripple, low noise, etc. Yet domestic research theory to high pressure helicalrotor pump is still at the beginning stage and lacks a set of perfect theory system. Thepurpose of this research is establishing a set of relatively perfect theory system ofdesign principle to helical rotor line-type, the characteristics to the engagement of gears,the characteristics of the pump function, structural design of the pump andmanufacturing technology of tools for the rotor for the high pressure helical rotor pump.This research confirms the equation of tooth profile curve by the principle ofcontinuous contact based on the meshing of tooth surfaces and solves the trapped oilphenomenon of traditional gear pump. According to the equation of tooth profile curve,the mathematical model of the helical rotor is established, then characteristics of gearsengagement are analysised which further proofs the principle of continuous contact.And then the detailed analysis of characteristics to the helical rotor pump is carried onby estalbishing the mathematics model of chamber and inlet-outlet of the pump anddeducing formulas of the pump flow, inlet-outlet sizes, radial force and beating rate ofthe radial force. As a result, the helical rotor pump has three characteristics: no flowripple, constant axial force and torque of the gear shaft, big radial force with ripple.Based on the theorys of the heilcal rotor pump, according to the technical indexs ofthe pump, we can obtain gear parameters and pump performance parameters (25MPapressure,90.65L/min flow,0%flow ripple). Structure design of the pump, includingthe sizes of the pump and ANSYS simulation of the main component parts of the pump,is acomplished. ANSYS simulation includes the optimization analysis of wall thicknessof pump body, modal analysis of driving gear shaft, static analysis of the gear shafts andgear contact analysis. ANSYS simulation identifies size of wall thickness, vibration typeof driving gear shaft, stress and deformation of the dangerous section of gear shaft andthe gears contact force. It ensures the reliability of the design of the structure size.As the special tooth profile of helical rotor, It is neccesary to design milling cuttersand the hob. According to space meshing theory, the rotary surface tooth profile of the milling cutter and formula of the basic hob worm are deduced out. Then profile offormer angle milling cutter and rake face profile of the former Angle hob are alsoresearched detailly. Based on theoretical calculation for milling cutters and hob, wedesign size of tools and plot engineering drawings of tools.In order to make helical rotor pump research more concise and more universal, Asystem software which is applicable to helical rotor pump and its complicated tooldesign is established and its platform is based on Matlab GUI. This system software cancomplete jobs below: gear parameter design, pump parameters design, gear cutting tooldesign and tool path planning of NC machining, which will link the whole designresearch of the helical rotor pump together effectively.