Patent ID: 8747087

Claim:
A vacuum scroll pump comprising: a first scroll and a second scroll which are co-operable for pumping fluid from an inlet to an outlet on relative orbiting motion of the first and second scrolls, wherein the first scroll comprises: a first scroll base from which a first scroll wall extends generally axially towards a second scroll base of the second scroll, wherein a first portion of the first scroll wall has formed in an axial end face thereof a first plurality of pockets distributed along the first portion for disrupting leakage of fluid from a high pressure side of the first scroll wall to a low pressure side of the first scroll wall, wherein a second portion of the first scroll wall has formed in the axial end face thereof a second plurality of pockets distributed along the second portion for disrupting leakage of fluid from the high pressure side of the first scroll wall to the low pressure side of the first scroll wall, and wherein a configuration of the first plurality of pockets is different than a configuration of the second plurality of pockets so that the first plurality of pockets and the second plurality of pockets disrupt leakage generated by conditions local to the first region and the second region, respectively.