Patent ID: 7836548

Claim:
A vacuum cleaner, comprising: a housing comprising a bottom, a top and a side interconnecting the top and the bottom; at least one bottom opening formed in the bottom of the housing; a cavity formed in the housing in fluid communication with the at least one bottom opening; an ultra violet light source configured to irradiate ultra violet light to a surface under the bottom; a hitting duster configured to beat the surface under the bottom; means for forcing air in a direction within the housing to form a negative pressure in the cavity such that an air flow can be made through the at least one bottom opening from outside the housing to the cavity during operation of the vacuum cleaner; at least one auxiliary opening formed on at least one of the side and the top, wherein the at least one auxiliary opening is also in fluid communication with the cavity such that a substantial air flow is made through the at least one auxiliary opening from outside the housing to the cavity as a negative pressure is formed in the cavity, even if the at least one bottom opening is completely blocked during operation of the vacuum cleaner; and wherein the at least one auxiliary opening is provided by a plurality of ribs formed on the at least one of the side and the top of the housing.