Rotary machine with orbiting twin blades, especially for expansion drive units and compressors

A rotary machine with orbiting twin blades, especially for expansion drive units and compressors, comprising

• a stator housing having an inner peripheral surface circumferentially delimiting an enclosed internal chamber extending along a stator axis;
• a rotor part received in said stator housing for rotation about a rotor axis parallel to and radially offset from said stator axis and including
• at least two entraining rings axially spaced from one another, and
• at least four entraining bars extending substantially parallel to said rotor axis at a radial distance therefrom, interconnecting said entraining rings, and defining respective slots between themselves;
• means for mounting said rotor part for rotation in said internal chamber about said rotor axis;
• a carrier shaft mounted in said internal chamber for rotation about a carrier shaft axis parallel to said rotor axis and extending over the entire axial length of said stator housing;
• at least two pairs of eccentric members provided on said carrier shaft for joint rotation therewith and centered on respective axes that are transversely offset from said carrier shaft axis in different radial directions;
• at least two twin blades each supported on one of said pairs of eccentric members for relative turning therebetween and including two blade portions passing through oppositely located associated ones of said slots of said rotor part into close proximity of said inner peripheral surface of said stator housing;
• and
• means for transmitting torque between said rotor part and said carrier shaft in a permanent 1:2 transmission ratio such that said carrier shaft with said eccentric members turns in the same direction as but at twice the speed of said rotor part when the rotary machine is in operation such that said eccentric members force said twin blades to conduct movements relative to said rotor part that cause such blades to follow said inner peripheral surface of said stator housing at said close proximity therefrom.