The Desigh Of The Heavy-duty Transmission Pianetary Gear Mechanism

In the background of market demand which changes significant, the RangeGroup which uses planetary in the heavy-duty transmission products has becomea trend。In order to conform to the development of the market situation, theplanetary structure of our company is also intense development to adapt tomarket demand. Planetary structure range group is one of the important part ofthe heavy commercial vehicle transmission, so its carrying capacity size,structural design whether is reasonable or not will be a direct impact on theoverall reliability of the transmission. Therefore, it must be conducted in-depthstudy for planetary gear mechanism on the range group technology, masteredthe design and methods of computation of planetary mechanism。It’s significantimportant to enhance the core competitiveness of the company’s productsIt’s difficult to design and calculate the planetary mechanism because of thecomplex structure. To simplify calculation, In this paper it’s calculated betweenthe sun gear and the planetary gear, planetary gear with large ring gear meshingpair agencies. It should be discussed to meet the installation conditions, theconcentric conditions,the adjacency conditions of the gear of the planetarymechanism. It’s calculated the center distance, teeth calculation, parametercalculation, strength calculation according to the set development target,determined gear parameterswith teeth checking according to meet therequirements of the case, It’s developed collection methods according to thedetermination of the load spectrum, received the S-N curve through benchtest.It’s calibrated gear strength according to the load spectrum, S-N curve.design safety rate shoud be more than1in accordance with the design goals. It’sdiscussed about the key parts of planetary mechanism eg:sun gear, planetary gear,planet carrier and the ring gear structure. it’s investigated the transmissionplanetary body structure now existing in the market,analyzed its advantages anddisadvantages. Select the ease of processing, to ensure that the structure of theperformance. Finally, according to cycles of the test conditions to develop,through experimental verification, to determine planetary mechanism designed tomeet the development goals. In this paper, it’s introduced on the development process of transmissionrange group planetary mechanism.Firstly, it’s analysed competitive products,made development target and life goals. In the planetary mechanism design, it’sdetermined the center distance, parameter calculation and checkingcomputations with teeth according to the ratio of teeth-distributing calculation.It’s discussed and summarized the methods of the planetary gear life standards.Lastly,according to the design life goals, develop fatigue test program, and verifythe design which can be achieved using target.In this paper, it has a certain guiding significance for beginners to masterplanetary mechanism transmission process development and design.