How to obtain high transmission performance and power density of gear reducer

The working environment of construction machinery is harsh. In actual driving, in addition to all the incentives brought by stable operating conditions including starting, shifting, braking, steering and other operations, it also bears unforeseen shock excitations from the working medium, which makes the planetaryGear reducerThe stress state of the bearing becomes extremely complicated.With high speed and heavy load comes high temperature, so the wear characteristics of planetary gear reducer bearings are very complex, and there are many influencing factors, such as the coupling of temperature field and stress field, the combination of temperature field and speed field, the speed field and stress Occasion, change of working gap, etc.Therefore, studying the wear characteristics of the planetary gear bearing of the high-speed planetary gear has become an important subject in the process of developing the transmission mechanism of the high-speed planetary gear reducer.
Usually, the planetary gear bearing of construction machinery transmission device adopts needle roller bearing, which is one of the parts that are easily damaged in the early stage, and is also one of the bottlenecks restricting the improvement of planetary transmission technology.In the transmission mechanism of the planetary gear reducer, the bearing on the planetary wheel bears a large load, not only bears the load caused by the whistling force on the bearing, but also bears the load caused by the centrifugal force of the planetary gear on the bearing.Especially when the rotation speed of the planet carrier is very high, the load caused by centrifugal force on the bearing may greatly exceed the load caused by the meshing force on the bearing, so the influence of centrifugal force on the bearing cannot be ignored [5].At present, the working speed of the planetary gear reducer mechanism of the transmission device is generally below 7000r/min. In order to obtain high transmission performance and power density, increasing the speed has become one of the commonly used effective measures. Therefore, it is proposed that the working speed can reach 11 OOOr/min or The development target of high-speed high-speed planetary mechanism, and the DN value of rolling bearing is about 0.3X106 mm^/111.Therefore, in the transmission of high speed, high load and wide temperature range, rolling bearings often cannot meet the requirements of service life, so it is an inevitable trend to explore the feasibility of using sliding bearings for planetary bearings in construction machinery transmissions under the existing structural conditions.