Pump device
A pump device for a motor vehicle includes: a pump having a first pump member and a second pump member, the first and second pump members being movable relative to one another; an electric drive having a drive housing and an output shaft rotatable with respect to the drive housing; and a gear mechanism, which couples the output shaft to the first pump member and, by reversing a direction of rotation of the electric drive, is switchable between a first and an opposite second transmission ratio. The gear mechanism has: a planet stage having a planet carrier rotationally fixed relative to the drive housing, and/or first and second freewheels, oppositely directed with respect to one another, and which are arranged axially behind one another, and/or the second pump member has a drive shaft rotatable relative to the output shaft.
1. A pump device for a motor vehicle, the pump device comprising:
a pump having a first pump member and a second pump member, the first pump member and the second pump member being movable relative to one another;
an electric drive having a drive housing and an output shaft rotatable with respect to the drive housing;
a gear mechanism, which couples the output shaft to the first pump member and, by reversing a direction of rotation of the electric drive, is switchable between a first transmission ratio and an opposite second transmission ratio,
wherein the gear mechanism has:
a planet stage having a planet carrier rotationally fixed relative to the drive housing, and
a first freewheel and a second freewheel, oppositely directed with respect to one another, and which are arranged axially one behind the other, and
the second pump member has a drive shaft rotatable relative to the output shaft,
wherein the first pump member is connected by the first freewheel to a sun wheel and/or connected in the second freewheel to an annulus of the planet stage of the gear mechanism, and
wherein a second drive, comprising an internal combustion engine, is coupled to the drive shaft.
2. The pump device as claimed in claim 1 , wherein the output shaft is connected by the first freewheel to the first pump member and/or the output shaft is rotationally fixed to the sun wheel of the planet stage of the gear mechanism.
3. The pump device as claimed in claim 1 , wherein the first pump member comprises a pump housing and the second pump member comprises a rotor arranged in the pump housing.
4. A motor vehicle comprising: the pump device as claimed in claim 1 ; and a vehicle transmission, wherein the pump device is configured as a hydraulic supply of the vehicle transmission.
5. A method for operating the pump device as claimed in claim 1 , wherein the electric drive is operated in a first operating mode with a first direction of rotation and in a second operating mode with an opposite second direction of rotation.