Patent ID: 6964559

Claim:
An axially pumping vacuum pump comprising: a pump chamber casing defining a pump chamber having a suction side, the pump chamber accomodating first and second co-operating rotors which are arranged on first and second parallel rotor shafts; a bearing/gear chamber having a first wall adjacent to the pump chamber and a second wall opposite to the first wall away from the pump chamber, the rotor shafts being cantilevered into the pump chamber and being supported by first bearings located in the first wall between the pump chamber and the bearing/gear chamber and second bearings located in the second wall, the bearings being located remote from the suction side; a drive motor accomodated within the bearing/gear chamber, the drive motor including a stator and an armature mounted to a motor drive shaft, the motor drive shaft extending, parallel to the rotor shafts, the motor drive shaft being supported in bearing located in the first and second walls with the armature between the bearings, a toothed drive gear, the drive gear engaging at least one toothed driven gear, the driven gear being one of attached to one of the rotor shafts, and a synchronization gear within the bearing/gear chamber that synchronizes rotation of the rotor shafts, the driven gear having a smaller diameter than the drive gear.