초록 ▼

An improved supercharger or blower (10) of the Roots-type with reduced airborne noise. The blower includes a housing (12) defining generally cylindrical chambers (32, 34) containing meshed lobed rotors (14, 16) having the lobes (14a, 14b, 14c, 16a, 16b, 16c) thereon formed with an end-to-end helical

An improved supercharger or blower (10) of the Roots-type with reduced airborne noise. The blower includes a housing (12) defining generally cylindrical chambers (32, 34) containing meshed lobed rotors (14, 16) having the lobes (14a, 14b, 14c, 16a, 16b, 16c) thereon formed with an end-to-end helical twist according to the relation 360°/2n, where n equals the number of lobes per rotor. Blower housing (12) also defines inlet and outlet ports (36, 38). The inlet port includes a longitudinal extent defined by housing wall surfaces (20f, 20h) and a transverse extent defined by housing wall surfaces 20g, 20i. Transverse wall surfaces (20g, 20i) are disposed substantially parallel to the associated rotor lobes. The outlet port includes a longitudinal extent defined by housing surfaces (20m, 20r) and a transverse extent defined by housing surfaces (20p, 20s). Spaces (32a, 34a) between adjacent lobes of each rotor transfer volumes of low-pressure inlet port air to relatively high-pressure outlet port air. Associated with the outlet port are first and second expanding orifices (42, 44) disposed on transversely opposite sides of the outlet port for controlling the rate of backflow into the transfer volumes and operative at predetermined rotor speed and pressure differential relationships to maintain a substantially constant backflow rate into each of the transfer volumes.

대표청구항 ▼

In a rotary blower of the backflow-type including a housing, inlet and outlet Ports having longitudinal and transverse boundaries formed by wall surfaces defined by the housing, and a chamber defined by the housing; first and second meshed lobed rotors disposed in the chamber for transferring volume

In a rotary blower of the backflow-type including a housing, inlet and outlet Ports having longitudinal and transverse boundaries formed by wall surfaces defined by the housing, and a chamber defined by the housing; first and second meshed lobed rotors disposed in the chamber for transferring volumes of relatively low-pressure inlet port air via spaces between adjacent, unmeshed lobes to relatively high pressure outlet port air; means for controlling the rate at which outlet port air backflows into the transfer volume; the improvement comprising: first and second expanding orifices disposed on transversely opposite sides of the outlet port and defining the control means, said orifices defined by transverse wall extensions of the outlet port wall surfaces and traversing of the transverse wall extensions by the lobes prior to traversal of the outlet port boundaries, and said expanding orifices alternately operative at predetermined rotor speeds and pressure differential relationships to maintain a substantially constant backflow rate into each of the transfer volumes.