CENTRIFUGAL IMPELLER, MOTOR-DRIVEN AIR BLOWER AND VACUUM CLEANER

摘要

PROBLEM TO BE SOLVED: To provide a highly efficient centrifugal impeller, motor-driven air blower and vacuum cleaner by preventing leakage of air. SOLUTION: Plural circumferential ribs 100 arranged on a bottom surface of an inducer 201 and circumferential recessed parts 101 plurally arranged on an inside surface of a rear surface shroud 200 so as to be opposed to the circumferential ribs 100 are fitted to surely seal air by a labyrinth effect to prevent air from flowing inside a centrifugal impeller 11 through clearance between the rear surface shroud 200 and the inducer 201 from clearance between a shaft hole 80 and a shaft 3 generated at assembling time.