Patent ID: 9556877
Date: 2017-01-31
CPC Classifications: F04D

Claim:
1. A multistage pump for conveying a pump fluid, wherein the pump fluid provided at an inlet pressure at a low pressure side (LP) of the pump ( 1 ) can be conveyed in the operating state to a high pressure side (HP) of the pump rotor ( 12 ) by means of a pump rotor ( 12 ) rotatably supported about an axis of rotation (A) in a pump stator ( 11 ) and wherein a rotor shaft ( 13 ) with a drive side and a non-drive side is arranged with the pump rotor ( 12 ) at an additional bearing ( 14 ), which is located on the drive side, whereby the rotor shaft ( 13 ) is supported on the drive side in an outer bearing and can be coupled to the drive by means of a coupling, characterized in that the additional bearing ( 14 ) is arranged between the outer bearing and the pump rotor ( 12 ) and a lubricating film which is formed from a lubricating fluid formed from the pump fluid can be formed on the drive side (AS) of the rotor shaft ( 13 ) between the rotor shaft ( 13 ) and the additional bearing ( 14 ) in a lubricating ring gap ( 15 ), with a lubricant line ( 16 ) being provided such that the lubricating fluid can be supplied to the lubricating ring gap ( 15 ) between the rotor shaft ( 13 ) and the additional bearing ( 14 ).