Power-Split Transmission for a Traction Drive and Method for Controlling the Transmission
AssigneeDana Rexroth Transmission Systems
InventorsMatthias Mueller, Walter Scandella, Steffen Mutschler
Life of this patent
Estimating the term…
Abstract
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.
Claims12
A power-split transmission for a traction drive having a drive machine, comprising:
- an input shaft configured to be coupled to the drive machine of the traction drive;
- a hydraulic power branch including a hydraulic pump configured to be coupled to the input shaft;
- an adjustable displacement volume;
- a hydraulic motor configured to be connected fluidically to the hydraulic pump via a first working line and a second working line;
- a further power branch configured to be coupled to the input shaft, the further power branch including a control valve via which a control pressure medium is configured to be applied to a hydraulic actuating device of the hydraulic pump as a function of a velocity setpoint value, the hydraulic pump configured such that a working pressure of the hydraulic motor or a pressure derived therefrom is effective in a direction of reducing the displacement volume;
- and
- a pressure-control device configured to set a control pressure of the control pressure medium to a setpoint value, the set point value dependent on a drive range of the transmission or the traction drive.
A method for setting a control pressure of a power-split transmission for a traction drive having a drive machine, comprising:
- determining a drive range;
- and
- setting a control pressure as a function of the determined drive range with a pressure-control device,
- wherein the power-spilt transmission includes
- an input shaft configured to be coupled to the drive machine of the traction drive,
- a hydraulic power branch including a hydraulic pump configured to be coupled to the input shaft,
- an adjustable displacement volume;
- a hydraulic motor configured to be connected fluidically to the hydraulic pump via a first working line and a second working line, and
- a further power branch configured to be coupled to the input shaft, the further power branch including a control valve via which a control pressure medium is configured to be applied to a hydraulic actuating device of the hydraulic pump as a function of a velocity setpoint value, the hydraulic pump configured such that a working pressure of the hydraulic motor or a pressure derived therefrom is effective in a direction of reducing the displacement volume.
Dependencies are inferred from the claim text.