Multi-hubbed separable blade agitators

Claim 1

Agitator assembly comprising: (a.) a hollow tube drive shaft with a closed end, coated with glass on the external surfaces thereof, said glass coating which is finished machined along the section of said drive shaft to which at least one agitator blade assembly is to be mounted to a tolerance of ±0.0004"; (b.) at least two agitator blade assemblies, coated with glass on the external surfaces thereof, interference fitted to said finished machine section of said drive shaft, the abutting faces of said at least two agitator blade assemblies being in substantial contact with each other, each of said agitator blade assemblies comprising: (i) a hub with an internal bore with a bore height which is no less than 1" in diameter for each 13/4" of drive shaft diameter, said internal bore having a glass coating which is finish machined to a thickness range of 0.0400" to 0.0456", said glass coated internal bore of said hub which does not vary in size more than ±0.0002" in diameter from the size of any other glass coated internal hub bore of any other agitator blade assembly of said agitator assembly; and (ii) at least one blade projecting radially from said hub; (iii) wherein each face of said hub which abuts and comes into substantial contact with a face of another hub is within ±0.0010" of being perpendicular to the axis of said internal bore; and (iv) wherein the wall thickness of each of said hubs is substantially greater than the wall thickness of said hollow tube drive shaft; (c.) wherein said drive shaft is composed of metal and wherein each of said hubs is composed of the same grade of metal as each of said other hubs and wherein the coefficient of expansion and contraction of the drive shaft and each of said hubs is equivalent; and (d.) wherein said glass coating is composed of a glass material which contains at least 60% SiO 2 and at least ten additional oxides.