Power steering mechanism for a vehicle

A steering assistance device for a vehicle, comprising:

• an input shaft for introducing a torque from a steering column of the vehicle into the steering assistance device;
• a torque sensor, wherein the torque sensor is configured to detect the torque introduced via the input shaft and to provide a sensor signal which represents the detected torque;
• an output shaft for conducting the torque out of the steering assistance device;
• a gear unit, wherein the gear unit is configured to mechanically transmit the torque from the input shaft to the output shaft;
• a steering housing, wherein the gear unit is arranged within the steering housing;
• and
• a drive unit, wherein the drive unit is configured to charge the gear unit with a hydraulic working medium in a manner dependent on the sensor signal, wherein
• the drive unit and the torque sensor are arranged so as to be in mechanical contact with the steering housing,
• the drive unit has a pump for conveying the working medium and a motor for driving the pump,
• the drive unit has a reservoir for containing working medium, wherein at least the pump is arranged within the reservoir, and
• the input shaft, the torque sensor, the gear unit, and the drive unit are arranged in a row along a longitudinal axis.