摘要 |
A vacuum pump of the regenerative type comprising a rotor and a stator body in which the rotor is adapted for rotation and in which the rotor has a series of blades positioned in an annular array on a side of the rotor the stator has an annular channel within which the blades can rotate having a cross-sectional area greater than that of the individual blades except for a small part of the channel which has a reduced cross-section providing a close clearance for the blades, wherein the rotor has at least two series of blades positioned in concentric annular arrays on a side of the rotor and the stator has a corresponding number of channels within which the blades of the arrays can rotate and means are provided to link the channels to form a continuous passageway through which gas being evacuated by the pump can pass. <IMAGE> |