Tank agitator having a clean-in-place shaft and seal assembly

A shaft and seal assembly for sealing an opening of a wall through which the shaft is configured to extend, the shaft and seal assembly comprising:

• a shaft having a longitudinal shaft axis and axially opposite first and second ends, the shaft being dimensioned to extend axially through the opening of the wall with the first and second ends of the shaft on opposite sides of the wall, the shaft also being configured and adapted to rotate about the shaft axis relative to the wall and to be axially movable between an operating position and a cleaning position relative to the wall and the wall opening when the shaft is positioned extending axially through the wall opening;
• an annular sealing member positioned on the shaft where it will sealably close the wall opening by engaging the wall when the shaft is in the operating position;
• and
• a pusher member mounted on the shaft for axial movement of the pusher member with the shaft, the pusher member being positioned on the shaft where it is spaced from the sealing member when the shaft is in the operating position and where the pusher member will engage the sealing member and separate the sealing member from the wall as the shaft is axially moved from the operating position to the cleaning position.

A shaft and seal assembly for sealing an opening of a wall through which the shaft is configured to extend, the shaft and seal assembly comprising:

• a shaft having a longitudinal shaft axis and axially opposite first and second ends, the shaft being dimensioned to extend axially through the opening of the wall with the first and second ends of the shaft on opposite sides of the wall, the shaft also being configured and adapted to rotate about the shaft axis relative to the wall and to be axially movable between an operating position and a cleaning position relative to the wall and the wall opening when the shaft is positioned extending axially through the wall opening;
• a first annular sealing member positioned on the shaft where it will sealably close the wall opening by engaging the wall when the shaft is in the operating position, the first sealing member being dimensioned such that it is free to rotate about the shaft axis relative to the shaft and such that it will be held stationary against the wall when the shaft is in the operating position and the shaft is rotated about the shaft axis relative to the wall;
• a second annular sealing member positioned on the shaft where it will engage the first sealing member when the shaft is in the operating position, the second sealing member being sealed and attached to the shaft for rotation therewith in a manner such that the second sealing member is in sliding rotational engagement with the first sealing member when the shaft is in the operating position and the shaft is rotated about the shaft axis relative to the wall, the second sealing member also being axially attached to the shaft in a manner such that the second sealing member will be axially separated from the first sealing member when the shaft is in the cleaning position;
• and
• a pusher member responsive to axial movement of the shaft and positioned on the shaft where it is spaced from the first sealing member when the shaft is in the operating position, the pusher member being shaped to engage the first sealing member and to separate the first sealing member from the wall when the shaft is axially moved from the operating position to the cleaning position.

A shaft and seal assembly for sealing an opening of a wall through which the shaft is configured to extend, the shaft and seal assembly comprising:

• a shaft having a longitudinal shaft axis and axially opposite first and second ends, the shaft being dimensioned to extend axially through the opening of the wall with the first and second ends of the shaft on opposite sides of the wall and to rotate about the shaft axis relative to the wall and the wall opening when the shaft is positioned extending axially through the opening of the wall;
• a seal retainer axially and rotationally fixed to the shaft;
• a first annular sealing member positioned around the shaft and axially movable between an operating position and a cleaning position relative to the shaft, the first sealing member moving axially away from the seal retainer as the first sealing member moves from the operating position to the cleaning position, the first sealing member being dimensioned such that the shaft is free to rotate relative to the first sealing member and such that it will seal against and remain stationary relative to the wall when the shaft is positioned extending axially through the opening of the wall and the first sealing member is in the operating position;
• a second annular sealing member positioned around the shaft where it will be axially biased between the first sealing member and the seal retainer to sealably close the wall opening when the shaft is positioned extending axially through the wall opening and the first sealing member is in the operating position, the second sealing member being dimensioned to permit the second sealing member to axially slide relative to the shaft;
• and
• a pusher member axially fixed to the shaft and positioned where it is spaced from the second sealing member when the shaft is positioned extending axially through the wall opening and the first sealing member is in the operating position, the pusher member being shaped to engage the second sealing member to limit axial translation of the second sealing member relative to the shaft as the first sealing member is moved from the operating position to the cleaning position to axially separate the second sealing member from the first sealing member.