This impeller is equipped with: an impeller body formed from a resin and shaped as a disk with an axis as the center thereof, and having a boss hole section formed therein which a rotating shaft for rotating around the axis engages; compressor blades provided on the front-surface side of the impeller body; and a ring-shaped reinforcing ring provided inside the impeller body in the circumferential direction of the impeller body.

A rotary machine includes a machine stator and a machine rotor rotatable relative to the machine stator and having a metal shaft portion, a composite impeller portion, and at least a first metal ring portion securing the composite impeller portion to the metal shaft portion, the metal ring portion having a first interface with the composite impeller portion and a second interface with the metal shaft portion.

A compressor having a housing and a rotor, the rotor having an impeller at least on one side; a compressor chamber being formed between the impeller and the housing, the rotor being rotationally mounted, an annular sealing channel being formed between the rotor and the housing, the sealing channel being routed from the compressor chamber to a zone having a lower pressure; a throttling section being provided in the sealing channel; the sealing section being configured in closer proximity to the low-pressure zone than to the compression chamber.

A vacuum pump comprising a turbomolecular stage and a drag stage, the vacuum pump comprising a stator and a rotor. The rotor comprises a turbomolecular rotor and a drag rotor attached together. The turbomolecular rotor comprises a hub from which a plurality of blades extend, the hub comprising a mounting portion for mounting to a spindle of a motor and a hollow cylindrical portion, the hollow cylindrical portion extending from the mounting portion towards an outlet end of the turbomolecular stage. The drag rotor comprises a cylindrical skirt and an attachment part extending away from the cylindrical skirt, the attachment part extending within the hollow cylindrical portion of the hub of the turbomolecular rotor and being attached thereto at a point that is closer to the mounting portion than to the outlet end of the turbomolecular rotor.

The invention relates to a side-channel compressor (1) for a fuel cell system (37) for conveying and/or compressing a gaseous medium, in particular hydrogen, comprising a housing (3); a compressor chamber (30) which is situated in the housing (3) and which has at least one encircling side channel (19, 21); a compressor impeller (2) which is situated in the housing (3) and which is arranged so as to be rotatable about a rotational axis (4), wherein the compressor impeller (2) has conveying cells (5) arranged on the impeller circumference in the region of the compressor chamber (30); and in each case one gas inlet opening (14) formed on the housing (3) and one gas outlet opening (16), which are fluidically connected together via the compressor chamber (30), in particular the at least one side channel (19, 21). The housing (3) has a respective first and second end face (32, 34) radially to the rotational axis (4), each end face facing the compressor impeller (2), and a first and second functionally relevant gap dimension (36, 38) is formed in the region of each gap surface. According to the invention, the compressor impeller (2) is designed in multiple parts and has a first impeller shell (10) and a second impeller shell (12). The impeller shells (10, 12) are arranged adjacently to each other axially to the rotational axis (4) in particular, and each impeller shell is at least partly made of a plastic.

A method of loading a rotating assembly of a turbocharger can include positioning a swage collar on an end portion of a turbocharger shaft that extends through a through bore of a compressor wheel; applying a pulling force to the end portion of the turbocharger shaft to achieve a desired amount of loading; deforming the swage collar to form a swaged collar fixed to the end portion of the turbocharger shaft; and releasing the pulling force wherein the swaged collar maintains the desired amount of loading.

A compressor wheel assembly of a turbocharger can include a compressor wheel that includes a through bore that extends from a base portion to a nose portion of the compressor wheel; a turbocharger shaft disposed in the through bore of the compressor wheel where the turbocharger shaft includes an end portion that extends axially away from the nose portion of the compressor wheel; and a swaged collar fixed to the end portion of the turbocharger shaft.

The invention relates to a shaft-hub connection (1), particularly for mounting a rotor wheel on a shaft (10). The shaft-hub connection (1) comprises a shaft (10), a hub (20) and a filler material (30). The shaft (10) comprises an end section (11) on one end. A receiving region (21) is arranged in the hub (20). The end section (11) is arranged in the receiving region (21), with an intermediate layer of the filler material (30) positioned inbetween. The filler material (30) forms undercuts in the axial and rotational direction, in relation to the end section (11) and in relation to the receiving region (21), so as to create a positive embodiment of the shaft-hub connnection (1).

A vacuum pump and a washer which can reduce vibration of a rotor and the rotor which can reduce the vibration are provided. When an inertia moment ratio which is a ratio between the inertia moment around a z-axis and the inertia moment around an x-axis or a y-axis is larger than 1, a natural frequency ω.sub.2 does not match a rotational frequency Ω.sub.z but goes away from that. When the natural frequency ω.sub.2 matches the rotational frequency Ω.sub.z, the rotor vibrates and thus, a fatigue failure occurs in a rotor blade. When the rotor is to be made larger in a radial direction of a rotating shaft, a value of the inertia moment ratio is set to a value larger than 1.

A compressor has a rotor. The rotor includes a plurality of impellers that include a disk having a solid structure having a buried center, and are adjacent to each other in an axial direction, and a plurality of bolts for fixing the plurality of impellers together. The disk has a disk surface facing the axial direction and a bolt hole penetrating the disk at a position deviated outward from an axis in a radial direction. The disk surface includes a contact surface of which at least a part is located outside the bolt hole in the radial direction, and a non-contact surface which is a region inside the contact surface in the radial direction.