Wet pick-up vacuum unit motor bearing air seal

In a wet pick-up type vacuum cleaner fan unit with a cleaning working air centrifugal fan impeller mounted on a fan shaft supported in a lubricated bearing received in a central socket of a fan housing end wall,

• said impeller peripherally discharging to a working air outlet of the housing located adjacent to said end wall,
• the improvement comprising:
• a centrally apertured disk plate circumferentially engaged and sealed upon and spaced from the fanward inner face of the said end wall;
• a plurality of angularly spaced auxiliary or sealing air inlets through said wall from the exterior to an air flow space defined between the disk and end wall face;
• an auxiliary centrifugal fan of smaller diameter than, and in back-to-back relation with, said working fan impeller,
• said auxiliary fan being clamped on said shaft with its inlet eye facing the central aperture of said disk to receive auxiliary air therefrom;
• a shield cup received with circumferential spacing in the auxiliary fan inlet eye and
• having a centrally apertured flat bottom conjointly clamped with said fans on said shaft, and
• extending through the central aperture of the disk to define with the edge thereof a discharge outlet from said flow space into the auxiliary fan eye;
• whereby said shield and disk provide structural screening around said bearing socket and shaft, and
• said auxiliary fan, shield and disk further moving auxiliary screening and sealing air axially exterior to the socket and on out to a common discharge of said back-to-back auxiliary and working air fans to prevent foam and working air entrained detergent from approaching said bearing.