Tractor step-less gearbox with single planet row for convergence and use method thereof

The invention relates to a tractor step-less gearbox with a single planet row for convergence and a use method thereof. The tractor step-less gearbox comprises the 2Z-X(B) planet row, a pump-controlled hydraulic motor, a brake, three sets of two-way clutches and a plurality of groups of gear pairs. Two gears are introduced in the gear drive between a motor shaft and a sun axle, so that non-equal difference multi-stage step-less speed regulation is realized at the tractor step-less gearbox with single planetary row sink flow; and power convergence is realized by using the 2Z-X(B) planet row with a duplex planet wheel. Compared with a traditional 2Z-X(A) planet row, the gearbox has a larger speed regulation range; and by means of a single for convergence planet row design, the overall structure of is simple and compact, and cost is easy to control. 本发明涉及种单行星排汇流的拖拉机无级变速箱及使用方法，其中拖拉机无级变速箱，包括2Z-X(B)行星排、泵控液压马达、制动器、三组双向离合器和多组齿轮副。通过在马达轴与太阳轮轴之间的齿轮传动中引入两个挡位，可使单行星排汇流的拖拉机无级变速箱实现非等差多区段无级调速；采用具有双联行星轮的2Z-X(B)行星排实现功率汇流，较之于传统的