Power-split transmission for a traction drive and method for controlling the transmission

摘要

A power-split transmission for a traction drive includes a hydraulic power branch and a further power branch. In order to control a velocity, a displacement volume of a hydraulic pump of the hydraulic power branch is configured to be adjusted by a hydraulic actuating device. For the purpose of adjustment, a control pressure medium can be applied to the actuating device by a control valve. An additional pressure-control device is configured to be used to set a control pressure of the control pressure medium to a setpoint value which is dependent on a drive range of the transmission or of the traction drive.

主权项

1. A power-split transmission for a traction drive having a drive machine, comprising:
an input shaft coupled to the drive machine of the traction drive; a hydraulic power branch including:
a hydraulic pump coupled to the input shaft and including an adjustable displacement volume and a hydraulic actuating device configured to set the adjustable displacement volume;a hydraulic motor connected fluidically to the hydraulic pump via a first working line and a second working line;a pressure-control device including an inlet fluidly connected to a working pressure in one of the first and second working lines, and a pressure-medium outlet at which the pressure-control device is configured to set a control pressure of a control pressure medium to a setpoint value; anda control valve fluidly connected between the pressure medium outlet of the pressure-control device and the hydraulic actuating device of the hydraulic pump and configured to regulate application of the control pressure medium to the hydraulic actuating device as a function of a velocity setpoint value; a further power branch coupled to the input shaft in a power-split drive range and decoupled from the input shaft in a hydrostatic only drive range; and a control device operably connected to the pressure-control device and including a memory unit and a processor unit configured to execute programmed instructions stored in the memory unit to determine the setpoint value based on whether the transmission of the traction drive range is in the power-split drive range or the hydrostatic only drive range, produce a setpoint value signal corresponding to the setpoint value, and actuate the pressure-control device using the setpoint value signal.