Power split transmission, method of operating a power split transmission and motor vehicle with a power split transmission

A method for operating a power split transmission comprising a drive shaft, a first mechanical branch comprising a planetary gear arrangement with at least two sun gears, a first ring gear and a planetary web on which double planetary gears are arranged, which mesh with the sun gears and with the first ring gear, at least one of the sun gears being coupled to the drive shaft, a continuously variable second branch which can be connected at least partially to the first mechanical branch via the planetary gear arrangement and comprises at least two adjustable hydraulic units which can be energetically coupled to one another and can be operated in each case in both directions as a motor or pump, and an output shaft which can be coupled to the drive shaft via the first, mechanical branch and the second branch, wherein the planetary gear arrangement is assigned a planetary reversing gear by which the direction of rotation of the first mechanical branch can be reversed, wherein the planetary reversing gear has an axially adjustable shift sleeve, in one axial position of which the direction of rotation of the planetary web can be transmitted directly to the first, mechanical branch and in the other axial position of which the direction of rotation of the planetary web can be fed in reverse to the first, mechanical branch, wherein the method comprises:

• in a forward driving range, displacing the shift sleeve into an axial position which is not fixed in terms of rotation relative to the transmission housing,
• wherein the first hydraulic unit is coupled to the ring gear via a gear wheel and a gear wheel on an outer ring of the ring gear,
• wherein the second hydraulic unit is coupled to a summing shaft via a first clutch, a gear wheel and a gear wheel,
• wherein the first hydraulic unit is pivoted from a pivoting position with a pivoting angle of 0° in a first pivoting direction into a positive angular range and is operated as a pump, and
• wherein the second hydraulic unit is operated as a motor.

A method for operating a power split transmission comprising a drive shaft, a first mechanical branch comprising a planetary ear arrangement with at least two sun gears, a first ring gear and a planetary web on which double planetary gears are arranged, which mesh with the sun gears and with the first ring gear, at least one of the sun gears being coupled to the drive shaft, a continuously variable second branch which can be connected at least partially to the first mechanical branch via the planetary gear arrangement and comprises at least two adjustable hydraulic units which can be energetically coupled to one another and can be operated in each case in both directions as a motor or pump, and an output shaft which can be coupled to the drive shaft via the first, mechanical branch and the second branch, wherein the planetary gear arrangement is assigned a planetary reversing gear by which the direction of rotation of the first mechanical branch can be reversed, wherein the planetary reversing gear has an axially adjustable shift sleeve, in one axial position of which the direction of rotation of the planetary web can be transmitted directly to the first, mechanical branch and in the other axial position of which the direction of rotation of the planetary web can be fed in reverse to the first, mechanical branch, wherein the method comprises:

• in a reverse travel range, moving the shift sleeve into the axial position in which the shift sleeve is fixed against rotation relative to the transmission housing,
• wherein the first hydraulic unit is operated as a pump and the second hydraulic unit is operated as a motor, and
• wherein the first hydraulic unit H1 is pivoted from a pivoting position of 0° into a second pivoting direction into a negative angular range.