operating range 50 of the hydraulic transformer is chosen such that although the transformer can be used for driving and braking in both directions of rotation four quadrant use the settings of the transformer are asymmetrical so that the driving torque can be higher than the braking torque the oil pressure in the chambers 65 pushes the barrel plate 56 against the swivel block 36 and the rotor 32 against the port plate 30 this is the main axial force except in situations where the oil pressure is very low in that situation the force of the spring 62 presses the rotor 32 and the barrel plate 56 against respective the port plate 30 and the swivel block 36 in order to prevent oil leakage and facilitate starting the forces on the rotor 32 in the axial direction of the rotation axis of the shaft 34 created by the oil pressure in the chambers 65 are necessary for creating a seal in the second axial bearing 59 and are in part balanced by forces of oil pressure in the piston canal 38 and the port 43 in the second axial bearing 59 between the rotor 32 and the port plate 30 the forces on the barrel plate 56 caused by the oil pressure in the chambers 65 and are necessary for creating a seal in the first axial bearing 57 these.