SEPARABLE BLADE STIRRER HAVING PLURAL BOSSES

摘要

A separable blade agitator assembly comrpising a hollow tube drive shaft with a closed end and at least two agitator blade assemblies coated with glass on the external surfaces thereof. The glass coating on the shaft is finished machined along the section of the drive shaft to which the agitator blace assembly is to be mounted to a tolerance of +/-.0004". The agitator blade assemblies are interference fitted to the machined section of the drive shaft, the abutting faces of the agitator blade assemblies being in substantial contact with each other. Each agitator blade assembly comprises a hub with an internal bore with a bore height which is no less than 1" in diameter for each 1-3/4" of drive shaft diamed, the internal bore having a glass coating which is finish machined to a thickness range of .0400" to .0456" and does not vary in size more than +/-.0002" in diameter from the size of any other glass coated internal hub bore of any other agitator blade assembly of the agitator assembly; and at least one blade projecting radially from the hub. Each face of a hub which abuts and comes into substantial contact with a face of another hub is within +/-.0010" of being perpendicular to the axis of the internal bore; the wall thickness of each of the hubs is substantially greater than the wall thickness of the hollow tube drive shaft. The drive shaft is composed of stabilized metal and each of the hubs is composed of the same grade of metal as each of the other hubs and the coefficient of expansion and contraction of the drive shaft and each of said hubs is equivalent. The glass coating is composed of a glass material which contains at least 60% SiO2 and at least ten additional oxides.