Patent ID: 7963744

Claim:
A rotor for a vacuum pump, the rotor comprising a threaded body, a cavity extending axially into the body, means for supplying a coolant to the cavity, means for discharging coolant from the cavity, and means located within the cavity for guiding a coolant flow between the supply means and the discharge means, wherein the guiding means has an inner surface defining a bore and an outer surface located adjacent the body to enable heat to be transferred thereto from the body, and defines a plurality of slots extending along the guiding means, the slots being radially spaced from and in fluid communication with the bore, wherein the supply means comprises a supply tube located within a shaft attached to the body for supplying coolant to the guiding means, wherein the discharge means comprises a discharge line located within the shaft and means for conveying coolant from the slots to the discharge line, wherein the conveying means further comprises a plurality of second discharge lines located within the shaft and extending from an annular channel for receiving coolant from said slots to the discharge line.