Centrifugal compressor rotor mechanism

The invention relates to a rotor structure of a centrifugal compressor, which is connected with a power take-off and is used for preventing lubricant from leaking and recollecting the lubricant into an oil tank. The rotor structure at least comprises a rotating shaft with a rolling bearing and a screw cap, a bearing support for supporting the rolling bearing and a bearing pressure plate which is connected to the bearing support. The surface of the screw cap is provided with an oil throw, the bearing support is provided with an oil return hole, the bearing pressure plate is provided with a guiding oil sink which is communicated with the oil return hole, and the bearing support or the bearing pressure plate is provided with a first labyrinth ring for sheathing and contacting the screw cap; thereby leading the lubricant which is leaked from the rolling bearing to flow into the oil tank through the guiding oil sink and the oil return hole, and preventing the lubricant from leaking at the first labyrinth ring in v