ROOT TYPE VACUUM PUMP OR ROOT TYPE BLOWER

摘要

PROBLEM TO BE SOLVED: To provide a root type vacuum pump or a root type blower to improve the efficiency of a volume and an energy saving effect, reduce the generation of noise during operation, and lower the temperature of the whole of a device. SOLUTION: A suction port 2 is situated in a position exceeding a volume movement angle of 120 deg. from the center of each rotation shaft based on a virtual line (m) to interconnect the centers of the rotary shafts of rotors. A discharge port 3 is formed in a way that at least one air passage hole is formed in the peripheral wall part of a region ranging from a position exceeding a volume movement angle of 120 deg. in a direction opposite to a suction port from the center of each rotary shaft based ion a virtual line (m) to interconnect the centers of the rotary shafts of the rotors to a point which a casing inside diameter circle having a center being the center of each rotary shaft crosses. Closed spaces (s) surround by the adjoining laminate of the rotors and the inner wall surface of the casing are formed in two spots of one being the suction port side and the other being the discharge port side right after suction of air.