Design Of Involute Zero-Tooth-Difference Internal Gear Mechanism And Measure Method

Thrust-offset gear coupling is a new type of coupling. It is designed especially for submersible progressive cavity pumping system. It has the advantages of larger axial and radial bearing capacity, higher transmission efficiency, less energy loss, and longer lifespan, etc. The internal gear mechanism with zero-tooth-difference is an important mechanism in the thrust-offset gear-coupling device, but its design, machining and measure work is not enough and further research and discussion are necessary.The power of the rotor has been figured out, which is based on the law of conservation of energy and according to the theory displacement of the progressing cavity pump system, the depth of the well, the altitude of the working fluid level, the average viscosity of the lifting medium, the rotational speed of the pump, the diameter of the drill tubing etc. We have determined the offset between its stator and the rotor of the progressing cavity pump. And take this as basis to calculate the offset of the internal gear couple with zero-tooth-difference. Based on the foregoing theory, in view of the small radial direction size and withstanding the big axial torque of the internal gear couple with zero-tooth-difference, and according to the new formula which is valid for verifying the strength of the gear with zero-tooth- difference mechanism and the value of the offset, this work detailed introduces a method to choose its basic parameter. This paper presents a method to select modification coefficient of the in volute internal gear with zero-tooth-difference mechanism. Proposing that take the max of the superposition degree as objective function, take the tooth profile engaging equation and other constraint conditions as restricted qualification. Then make use of Multiplier Method in the Practical Method of Optimization to select modification coefficient, guarantee obtains the optimal solution.Because of the bigger modification coefficient and a fewer teeth of the internal gear couple with zero-tooth-difference, the internal gear is processed in the numerical control line cutting machine. In this thesis, the solid model of the internal gear with zero-tooth- difference was drawn with UG and the DWG file was transferred by the UG drafting module. In order to get the value of the offset error of the processed gear couple, the gear measure method was researched based on the three-coordinate measuring machine. Some measure method of gear error can be obtained in this paper. Such as total tooth profile error, total spiral line (tooth traces) error, total accumulated pitch error, radial run-out of tooth ring error and alteration quantity length of the common normal.At last, two specialized measuring tools are designed, one is used to measure the radial run-out of tooth ring error of gear, and the other is used for measuring the gear couple. The structure and the working principle can be obtained in the thesis.