Patent ID: 8226384

Claim:
A motor-fan unit comprising: an end plate having an aperture therethrough; a motor unit attached to said end plate and defining an evacuation zone therebetween, said motor unit having a rotating shaft which has a shaft end that is received through said aperture, said shaft maintaining a vacuum bore extending from an outlet port disposed proximate said shaft end to a vacuum port disposed upon an outer surface of said shaft located proximate said evacuation zone, wherein liquid collected within said evacuation zone is discharged through said vacuum bore; a fan unit attached to said shaft end, said fan generating a negative pressure about said outlet port when moved; and a labyrinth seal disposed within said aperture, said labyrinth seal maintaining a seal about said shaft, so as to prevent the intrusion of liquid through said end plate, wherein said labyrinth seal comprises an engagement seal receiving said shaft and attached to said end plate, and a spacer received and carried by said shaft, wherein said spacer has a spacer inner surface from which extends an outer wall at an angle such that rotation of said spacer by said shaft causes said outer wall to form a groove in said engagement seal to complete said labyrinth seal, wherein said spacer inner surface and said engagement seal form a gap therebetween, and wherein said gap is contiguous with said evacuation zone.