Patent ID: 6997601

Claim:
A clean-in-place agitator arrangement for agitating the contents of a sanitary tank, said tank having an outer wall, with drive means for the agitator arrangement being disposed outside the tank outer wall; the arrangement comprising a drive shaft; a shaft housing supported in said tank wall and extending from an exterior of said wall to an interior of said tank wall, said shaft housing supporting said drive shaft so that a proximal end thereof extends out an end of the shaft housing exterior of said tank wall and a distal end thereof projects out another end within said tank, said shaft housing having a hollow interior defining an open annulus between the housing and the drive shaft; said shaft housing including means for admitting a cleaning solution under pressure into said open annulus; and an impeller mounted on the distal end of said shaft; said shaft housing further including a pair of lip seals spaced from one another and disposed over said drive shaft at the respective ends of said shaft housing, said drive shaft having a constant diameter at least through said shaft housing and at the positions of said lip seals; and each said lip seal having an annular lip that extends along said shaft in the distal direction and lies against a circumferential surface of said shaft, so that when said cleaning fluid is applied through said means for admitting, the fluid passes the lip of the lip seal at the interior end of the shaft housing, so that the fluid sprays against a proximal side of said impeller.