Scroll pump having axially compliant spring element

A scroll pump, comprising:

• a frame;
• a stationary plate scroll fixed relative to the frame and having a stationary plate, and a scroll blade projecting axially from the stationary plate in a direction parallel to a longitudinal axis of the pump;
• an orbiting plate scroll including an orbiting plate, and an orbiting scroll blade projecting axially from the orbiting plate in a direction parallel to the longitudinal axis, and nested with the stationary scroll blade,
• at least one tip seal, each said at least one tip seal interposed between an axial end of the scroll blade of a respective one of the stationary plate and orbiting plate scrolls and the plate of the other of the stationary plate and orbiting plate scrolls;
• an eccentric drive mechanism supported by the frame and operative to drive the orbiting plate scroll in an orbit about the longitudinal axis,
• the eccentric drive mechanism including a drive shaft, and bearings each having an inner race, an outer race and rolling elements interposed between the inner and out races,
• the drive shaft comprising a crankshaft having a main shaft and a crank,
• the outer races of respective ones of the bearings being coupled to the frame and the orbiting plate scroll, and the inner races of the respective ones of the bearings being disposed on the main shaft and the crank, whereby the main shaft is supported by the frame and the orbiting plate scroll is carried by the crank via the bearings, and
• wherein the eccentric drive mechanism has an axially facing flexure-locating surface, and the crankshaft is supported such that it is movable axially relative to the inner races of the bearings;
• and
• an axial compliance system including at least one spring by which the inner races of the bearings are clamped axially, and a flexure interposed in an axial direction, parallel to the longitudinal axis of the pump, between the inner race of one of the bearings and said axially facing flexure-locating surface of the eccentric drive mechanism, the flexure having compliance in said axial direction.

A scroll pump comprising:

• a frame;
• a stationary plate scroll fixed relative to the frame and having a stationary plate, and a scroll blade projecting axially from the stationary plate in a direction parallel to a longitudinal axis of the pump;
• an orbiting plate scroll including an orbiting plate, and an orbiting scroll blade projecting axially from the orbiting plate in a direction parallel to the longitudinal axis, and nested with the stationary scroll blade,
• at least one tip seal, each said at least one tip seal interposed between an axial end of the scroll blade of a respective one of the stationary plate and orbiting plate scrolls and the plate of the other of the stationary plate and orbiting plate scrolls;
• an eccentric drive mechanism supported by the frame and operative to drive the orbiting plate scroll in an orbit about the longitudinal axis, and including a drive shaft and bearings,
• the drive shaft comprising a crankshaft having a main shaft and a crank,
• the orbiting plate scroll being carried by the crank, and the main shaft of the crankshaft being supported by the frame via said bearings, and
• wherein the eccentric drive mechanism has an axially facing flexure-locating surface, one of the bearings is a flexure-locating bearing, and the crankshaft is supported such that it is movable axially relative to the flexure-locating bearing;
• a flexure axially interposed between said axially facing flexure-locating surface and said flexure-locating bearing, the flexure having compliance in an axial direction parallel to the longitudinal axis of the pump and configured to enable movement of the flexure-locating surface to position the orbiting plate scroll in the axial direction;
• and
• at least one spring, and wherein the flexure-locating bearing is biased by and between the at least one spring and the flexure.