Patent ID: 7080976

Claim:
A fluid flow displacement rotary machine comprising: a casing including a first portion comprising an inclined rib formed in an inner surface thereof and a second portion without the inclined rib, said second portion being distinct from said first portion and being adjacent to said first portion along a circumferential direction of the casing; a shaft provided coaxially with the casing, said shaft and said casing being rotatable with respect to each other; a space defined by the inner surface of the casing and an outer surface of the shaft; a fluid inlet and a fluid outlet communicating with said space; two rotatable disks, each of the two disks including a recess that is engageable with the inclined rib, and being rotatably mounted on the shaft, wherein the shaft includes two grooves therein, each of which houses a portion of a corresponding disk and has a depth such that a bottom of the recess is always within the groove in the shaft, and wherein rotation of said two disks around respective axes thereof is synchronized with respect to each other; wherein when the shaft and the casing rotate with respect to each other, the two disks are moved with the shaft with respect to the casing, and a first disk of the two disks moves across the second portion to push fluid while the recess of the first disk is positioned within the corresponding groove in the shaft; and wherein while the first disk moves through the second portion of the casing, the recess of a second disk of the two disks engages with the inclined rib such that the second disk rotates about the axis thereof, and the first disk is rotated about the axis thereof synchronously with the second disk as the two disks move with the shaft.