|
(11) | EP 0 931 939 A3 |
(12) | EUROPEAN PATENT APPLICATION |
|
|
|
|
|||||||||||||||||||||||
(54) | Vacuum pump |
(57) The invention concerns a vacuum pump (1) for achieving high vacuum conditions comprising
a pump casing (5), a first plurality of molecular pumping stages (2) formed by rotor
disks (8a,8b) cooperating with stator rings (9a,9b) and housed in a first portion
(4a) of said pump casing, and a second plurality of pumping diaphragm stages (3) housed
in a second portion (4b) of said pump casing, a first electric motor (13) for driving
said rotor disks of the molecular stages, a second electric motor (30) for actuating
the diaphragms (40) of the diaphragm stages, and at least a common passage (7) for
the passage of the gas discharged from said molecular pumping stages (2) and sucked
by said diaphragm pumping stages (3). |