An assembly includes a bearing having an annular shape, a bearing support radially outward from the bearing, a squeeze film damper having a first end adjacent the bearing and a second end adjacent the bearing support with the second end forming a squeeze film damping surface, and a first spring between the bearing and the bearing support with the first spring configured to resist a movement of the bearing to center a shaft radially inward from the bearing.

A counter-rotating shaft assembly of a gas turbine engine includes an outer shaft rotatable in a first direction about a virtual rotational axis, an inner shaft counter-rotatable about the virtual rotational axis in a second direction that is opposite to the first direction, a differential bearing rotatably connecting the two shafts, a centering spring connecting the inner shaft to the differential bearing, and a squeeze film damper between the differential bearing and the inner shaft.

A damper system may include an inner damper having a first annular geometry and a textured surface. An outer damper may also have an annular geometry and be disposed about the inner damper. The outer damper may have a textured surface. The textured surfaces of the inner damper and outer damper may define a cavity that is configured to contain a viscous fluid.

A system for the axial retention of a holding ring for a bearing for guiding in rotation a rotary shaft of a turbomachine is disclosed. The system includes an annular bearing support and a bearing holding ring that is borne by the annular bearing support. The bearing holder ring includes an upstream ring configured to be brought into contact with the bearing support and a downstream ring that is elastically deformable. The bearing support has a first axial retention element, and the bearing holding ring has a second axial retention element. The first and second axial retention elements are configured to cooperate with one another to axially retain the bearing holding ring in the event of damage to the downstream ring.

A method of bowed rotor start response damping for a gas turbine engine is provided. A spring rate and a damping characteristic of one or more bearing supports in the gas turbine engine are selectively modified while a shaft of the gas turbine engine rotates below a speed which is adversely affected by a bowed rotor condition of the gas turbine engine.

A bearing holder includes an inner portion and an outer portion, wherein the inner portion includes a receiving contour for receiving the bearing and the outer portion is configured to be mounted on a housing. A transition area between the inner portion and the outer portion includes a spring. The transition area is at least partly in a plane perpendicular to an axial axis of the receiving contour and is at least partly in a plane with at least one part of the inner and the outer portion. The transition area includes an attenuator and the attenuator is configured to attenuate a vibration of the inner portion to reduce a transfer of the vibration from the inner portion to the outer portion. Further, an electric motor, a method for producing a bearing holder and a method for operating a bearing holder are described.

A floating brush seal assembly includes a ring-shaped housing defining a radially inwardly open internal cavity; a brush seal in the cavity and having bristles extending radially inwardly and offset to seal against a rotating body; a radial spring positioned to exert a radial inwardly directed force against the brush seal relative to the housing; and an axial spring positioned to exert an axially directed force against the brush seal relative to the housing.

An epicyclic gearing arrangement includes a planet gear rotatable on a planet bearing that is mounted via a support pin to a carrier of the epicyclic gearing arrangement. A spring film damper is disposed between the cylindrical outer surface of the support pin and the opposing inner surface of the inner ring of the planet bearing and includes an annular gap.

An epicyclic gearing arrangement includes a planet gear rotatable on a planet bearing that is mounted via a support pin to a carrier of the epicyclic gearing arrangement. A spring film damper is disposed between the outer surface of the bearing's outer ring and the opposing inner surface of the planet gear and includes an annular gap. The support pin and/or outer ring include oil feed holes that open into the respective annular gap(s).

The invention concerns a device for centring and guiding in rotation a rotating part rotating about a turbomachine axis, comprising a rolling bearing comprising an outer ring, a bearing support surrounding the outer ring, an annular attachment flange mounted on the bearing support and a flexible portion connecting the outer ring to the attachment flange and comprising first arms extending from the attachment flange in a first direction with a first radial component towards the inside, second arms extending from the outer ring of the rolling bearing in a second direction with a second radial component opposite the first radial component, towards the outside, and an annular base that the first arms and the second arms join; the first arms alternating circumferentially with the second arms.