Patent ID: 7488137

Claim:
An assembly removably supporting a plurality of impeller blades on a shaft for use within a vessel containing material to be mixed, comprising: a one-piece inner sleeve, being slidable over and connected to the shaft, comprising a first end and a second end, a substantially cylindrical inner surface, an outer surface having an outward-facing threaded region between the first and second ends and a slotted, outward-facing tapered conical surface located substantially near the second end, and an inward facing first O-ring receiving groove located adjacent the shaft on the inner surface at the first end of the sleeve; a one-piece outer hub having the plurality of impeller blades mounted to an outer surface of the hub, being slidable over and connected to the shaft, comprising a first end and a second end, an inner surface with an inward-facing threaded region between the first and second ends threadably engagable with the outward-facing threaded region of the inner sleeve and an inward-facing tapered conical surface substantially near the second end configured to cam along the slotted, outward-facing tapered conical surface of the inner sleeve so that tightening the outer hub causes the slotted portion of the inner sleeve to frictionally lock onto the shaft at an adjustable location on the shaft, an inward facing second O-ring receiving groove on an inner surface of the outer hub adjacent the first end of the inner sleeve, and an inward facing third O-ring receiving groove on the inner surface of the outer hub adjacent the shaft at the second end of the outer hub; a first O-ring received in the first O-ring receiving groove that provides a seal between the inner sleeve and the shaft; a second O-ring received in the second O-ring groove, that provides a seal between the inner sleeve and the outer hub; a third O-ring received in the third O-ring receiving groove, that provides a seal between the outer hub and the shaft; and wherein, upon securement of the sleeve and hub to the shaft, the seals isolate the internal sleeve to hub connection from the material to be mixed.