There is provided a free rotary fluid machine including: a main body which is provided in a hollow cylindrical shape, and has an elliptical inner circumferential surface; a rotor which is provided in the main body, and rotates about the same rotation center as the main body; tip seals which are provided at one side of the rotor so as to be in contact with the inner circumferential surface of the main body; and blades which are provided between the tip seals provided adjacent to each other, and supported by the tip seals, in which the blade has one end surface that faces the inner circumferential surface of the main body, and the other end surface that is opposite to one end surface, and centers of radii of curvature of one end surface and the other end surface are positioned at the same side. As described above, a space formed among the inner circumferential surface of the main body, the rotor, and the tip seal is sealed by the auxiliary tip seal, and as a result, it is possible to reduce friction between the tip seal and the main body and to prevent a leak of an introduced working fluid.

The present invention provides a fluid transfer apparatus comprising: a rotating shaft comprising a rotation unit extending along an axial direction and a first eccentric unit and a second eccentric unit disposed to be spaced apart from each other along the axial direction; a first rotor housing forming a first fluid compression space in the shape of an epitrochoid curved surface; a second rotor housing forming a second fluid compression space in the shape of an epitrochoid curved surface, and positioned to be spaced apart from the first rotor housing along the axial direction; a first rotor disposed in the first fluid compression space so as to delimit the first fluid compression space into multiple variable-displacement spaces, and coupled to the first eccentric unit while surrounding the first eccentric unit in the radial direction of the first eccentric unit; and a second rotor disposed in the second fluid compression space so as to delimit the second fluid compression space into multiple variable-displacement spaces, and coupled to the second eccentric unit while surrounding the second eccentric unit in the radial direction of the second eccentric unit.