Patent ID: 7674096

Claim:
A portable, rotating vane vacuum pump for evacuating a system to a pressure substantially below ambient pressure, said portable vacuum pump including: a housing having an inner surface with at least a portion thereof extending about a first axis and defining in part a bore, a rotor mounted within said bore for rotation about a second axis offset from and substantially parallel to said first axis, said rotor further including at least two vanes mounted for sliding movement within respective slots in said rotor, a motor to rotate said rotor in a first rotational direction about said second axis within said bore, said vanes having inner and outer edge portions with the outer edge portions being in contact with the inner surface of said housing as said rotor is rotated by said motor about said second axis within said bore separating said bore into a plurality of chambers with at least one of said chambers being at a pressure less than ambient pressure, said housing further including at least one inlet passage and at least one outlet passage through the inner surface in respective fluid communication with said bore, said inlet passage being in fluid communication with the system to be evacuated below ambient pressure, a lubricating oil system with a removable oil reservoir cartridge open to atmosphere and at ambient pressure, an oil inlet arrangement to supply oil from said reservoir cartridge to the bore of said housing to at least said one chamber while said motor is rotating said rotor and while said oil reservoir is open to atmosphere, said one chamber being at said pressure less than ambient pressure and said oil being drawn into said one chamber wherein the supplied oil is at ambient pressure prior to being drawn via the oil inlet arrangement into the one chamber at less than ambient pressure, and an oil return arrangement to deliver oil back from said bore in said housing to said reservoir cartridge, said oil return arrangement being vented to ambient air downstream of said housing wherein the delivered oil enters the reservoir cartridge at ambient pressure, said reservoir cartridge forming at least a portion of a sump for said oil being delivered by said return arrangement from the bore of said housing wherein substantially all of the oil in said portable vane pump including in the lubricating system thereof is contained in said reservoir cartridge, said portable vane pump having a main body and said reservoir cartridge including said sump portion thereof being removably attached to the main body of said portable vane pump by a manually operable arrangement wherein said reservoir cartridge including the sump portion thereof can be manually removed from the main body of the portable vane pump as a unit with substantially all of the oil in said portable vane pump including the lubrication system thereof contained in the removed reservoir cartridge.