Patent ID: 7237944

Claim:
A scraped heat exchanger apparatus comprising: a drive shaft with at least one outwardly directed blade mounting pin with the driveshaft movable between a supported, operative position and an unsupported, non-operative position; a housing tube having an inwardly facing inner surface; and at least four blades, each blade comprising a body having a cross section spanning between a first tip end and a second mounting end, and at least one projecting nub integral with the body and projecting generally radially outwardly from the blade body when the blade is in a mounted state, said nub dimensioned to project radially outwardly past the pin when the blade is in the mounted state, wherein the nub is dimensioned to provide a resting surface against the inner surface of the tube so that the nub of at least two blades supports the blades, the pin and the drive shaft when the blade, the pin and the drive shaft are in the unsupported, non-operative position in the housing tube, and wherein none of the nubs are in contact with the tube when the driveshaft is in the supported position.