Two power split path hydrodynamic drive train of the commercial tractor

Abstract

The article presents hydromechanical drive trains with a differential link at the input and output. As a differential link, three-link differential mechanisms with mixed gears mesh are used. The possible schemes of two-path hydrodynamic drive trains are investigated. It is shown that the operation mode of a two-path hydromechanical drive train is possible when the turbine wheel of the torque converter rotates in the direction opposite to the impeller rotation. This factor is taken into account when choosing the characteristics of a two-path hydromechanical drive train. It has been established that for the most common two-path hydromechanical drive train scheme, the planetary gear set characteristic reduction increases its maximum efficiency, decreases the torque converter active diameter and increases the relative speed ratio of the three-link differential spider pinion. It is shown that a two-path hydromechanical drive train in comparison with a one-path drive train allows for using more efficiently the engine transforming property to change the torque when changing the output load on the engine, which is very important for commercial tractors operating under variable load conditions.