Method for delivering a gas/liquid mixture fluid via a screw spindle pump that has a housing in which a drive spindle and a running spindle are accommodated. The spindles delimit together with the housing multiple pump chambers. A respective one of the pump chambers that is initially open toward the respective fluid inlet is closed off. The resulting closed-off pump chamber is moved axially toward the fluid outlet and, there, upon attainment of an opening rotation angle, is opened toward the fluid outlet. The drive spindle is driven so that the pressure in the respective pump chamber prior to and/or upon attainment of the opening rotation angle is increased in relation to the suction pressure of the screw spindle pump by at most 20% or by at most 10% of a difference in pressure between the suction pressure and the pressure in the region of the fluid outlet.

A method for delivering a gas/liquid mixture fluid via a screw spindle pump that has a housing forming at least one fluid inlet and one fluid outlet and in which a drive spindle and a running spindle, coupled in terms of rotation, are accommodated. The spindles, in each rotation position of the drive spindle, delimit together with the housing multiple pump chambers. The drive spindle is rotated by a drive in a drive direction, whereby a respective one of the pump chambers that is initially open toward the respective fluid inlet is closed off. The resulting closed-off pump chamber is moved axially toward the fluid outlet and, there, upon attainment of an opening rotation angle, is opened toward the fluid outlet. The drive spindle is driven so that, for a given pump geometry of the screw spindle pump, the pressure in the respective pump chamber prior to and/or upon attainment of the opening rotation angle is increased in relation to the suction pressure of the screw spindle pump, which prevails in the region of the respective fluid inlet, by at most 20% or by at most 10% of a difference in pressure between the suction pressure and the pressure in the region of the fluid outlet.

Provided is an electric oil pump that does not degrade assembly operability and does not require a complicated configuration. The electric oil pump includes a motor portion that has a motor shaft disposed along a center axis extending in an axial direction; a pump portion that is disposed on one side of the motor portion in the axial direction, is driven by the motor portion via the motor shaft, and suctions and ejects an oil, and an inverter portion that is disposed on one side of the pump portion in the axial direction and drives the motor portion, the motor shaft penetrates through the pump portion, and the electric oil pump further includes a rotation angle sensor that is disposed at the inverter portion and detects a rotation angle of the motor shaft.