Patent ID: 6880536

Claim:
A rotary blower comprising a housing, first and second meshed, lobed rotors rotatably disposed in the housing for transferring relatively low pressure inlet port air to relatively high pressure outlet port air; first and second meshed timing gears fixed relative to said first and second rotors, respectively, for preventing contact of said meshed lobes; an input drive adapted to be rotatably driven by a positive torque, about an axis of rotation in one drive direction at speeds proportional to speeds of a periodic combustion engine; and a torsion damping mechanism for transmitting engine torque from said input drive to said first timing gear, said torsion damping mechanism including a first member fixed to rotate with said input drive, a second member fixed to rotate with said first timing gear, and a helical torsion spring having an input end fixed to rotate with said input drive and an output end fixed to rotate with said first timing gear, said torsion spring defining a normal inside diameter surrounding, and closely spaced apart from, an outer cylindrical surface defined by said first and second members; characterized by: (a) said housing defining a chamber containing a quantity of fluid whereby rotation of said first and second) timing gears results in the generation of an air-oil mist within said chamber; (b) said first and second members defining therebetween an axial gap disposed axially intermediate said input end and said output end of said torsion spring; and (c) one of said first and second members defining an angled passage having a radially outer end in communication with said axial gap, and a radially inner end in communication with the axially opposite end of said member, whereby rotation of said first and second members generates a flow of said air-oil mist through said angled passage and said axial gap and between said outer cylindrical surface of said first and second members and said inside diameter of said torsion spring.