Research On Transmission Scheme Of Crane Planetary Reducer Based On Equal Strength

With the rapid development of Chinese construction machinery, the market demand for cranes and their transmission device-reducer becomes larger. As planetary gear transmission is the critical transmission mechanism of planetary reducer, the design of its scheme affects the transmission performance and the characteristics of mechanical equipment. Aiming at2K-H (NGW) planetary reducers used in a series of cranes, the influence of gear parameters and structure of key components on gear equal strength is carefully studied. Meanwhile, the corresponding design software is worked out, in order to design the gear system of planetary reducers in procedure.The major work of this paper is as follows:(1) The gear transmission scheme of planetary reducers used in cranes is researched. Based on equal strength principle, the calculation method and design flow of distribution tooth number are deeply studied, and a set of accurate design method for transmission system of planetary gears is summarized, and the software is developed.(2) Based on ISO6336-2006, the latest calculation rules for strength of gears, and considering the working characteristics and operating requirements, the influence of gear parameters on equal strength is studied. The calculation module of gear strength is developed on the basis of Matlab.(3) Modification coefficient of planetary reducer gears is carefully studied. Considering equal strength principle and constraints for modification coefficient values, the optimization mathematic model is set up. And the modification coefficient can be obtained in procedure, ensuring to meet the engineering requirements.(4) Performance indexes and evaluation methods of planetary gear transmission system scheme evaluation are researched. The values representing significance are respectively distributed to equal pitting strength and equal bending strength. As a result, the multiple indexes comprehensive evaluation program is obtained.The conclusions are applied in design of planetary reducers of25T truck crane. A reducer test platform is designed and the test is carried out. Test results show that the performance of the planetary reducer which is designed with the method brought up by this paper is extremely good.