Patent ID: 8517679

Claim:
A sealing apparatus between a rotor and a housing of a continuous flow machine, wherein the rotor comprises a shaft and at least one bladed wheel, and the shaft is arranged in a shaft bushing hole in the housing, wherein the sealing apparatus comprises two piston ring sealing points, which are arranged at an axial distance from one another, the two piston ring sealing points comprising an outer piston ring sealing point which is located closest to the bladed wheel, and an inner piston ring sealing point, wherein the piston ring sealing points each comprise a piston ring, a cylindrical contact surface on the housing, and a projection with an axial stop surface on the rotor, wherein the piston ring of the outer piston ring sealing point has an external radius which is greater than an external radius of the piston ring of the inner piston ring sealing point, wherein the piston ring of the outer piston ring sealing point has an internal radius which is less than an internal radius of the piston ring of the inner piston ring sealing point, wherein an internal radius of the cylindrical contact surface of the outer piston ring sealing point is greater than an internal radius of the cylindrical contact surface of the inner piston ring sealing point, and wherein a maximum radial extent of the axial stop surface on the projection on the rotor of the outer piston ring sealing point is less than a maximum radial extent of the axial stop surface on the projection on the rotor of the inner piston ring sealing point, such that the axial stop surfaces on the projections on the rotor are radially stepped with respect to one another.