Hydrostatically mechanical power shift transmission, in particular for mobile construction - and working machines, as well as a method for controlling a power shift transmission

摘要

A power shift gear, in particular for mobile building and working machines, has at least two hydromotors (2, 3) that are driven by at least one pump (12, 13) and that co-operate each at the side of their input shafts with at least one gear pair (5, 6; 8, 9). The hydromotors (2, 3) are interconnected by a clutch (17) in order to add the torque of both gear pairs in a first driving range of the building and working machine. The power shift gear further has at least one planetary gear (10) with at least one driven shaft (21) and a ring gear (22) that may be locked by at least one brake (20). In another driving range of the building and working machine that follows the first driving range, at least one of the hydromotors (3) may be uncoupled from the driving shaft (4) of the other hydromotor (2) by means of the clutch (17) and may be frictionally coupled to the ring gear of the planetary gear (10) by another clutch (18) in the area of its driving shaft so that the speeds of rotation of both hydromotors may be mechanically added by superposition.