An air starter for starting a turbine engine that includes a housing, a turbine member, a drive shaft, and at least one bearing assembly. The housing can define an interior where the turbine couples to the drive shaft that is rotatably supported by the least one bearing assembly. A lubricant passageway can provide lubrication to the at least one bearing assembly.

A gas turbine engine comprises a gearbox comprising a sun gear, an annulus gear, a plurality of planet gears and a planet gear carrier. The sun gear meshes with the planet gears and the planet gears mesh with the annulus gear. Each planet gear is rotatably mounted in the planet gear carrier. The planet gear carrier comprises a plurality of axles arranged parallel to the axis of the gearbox. The axially spaced ends of each axle are secured to the planet gear carrier. Each planet gear is rotatably mounted on a corresponding one of the axles by a bearing arrangement. Each bearing arrangement comprises a journal bearing and a rolling element bearing and each planet gear is rotatably mounted on a journal bearing and each journal bearing is rotatably mounted on an axle by at least one rolling element bearing.

A bearing element includes an inner surface (54) configured to receive a cylindrical shaft (18). The inner surface (54) includes a smooth profile having a plurality of sections (502). Each section (502) having a taper portion (506) between a first arc-span point (512) and a second arc-span point (514), a constant-radius portion (508) between the second arc-span point (514) and a third arc-span point (516), and a transition portion (510) between the third arc-span point (516) and a fourth arc-span point (518). An inner-surface radius dimension (520) changes from an inner-diameter major dimension to an inner-diameter minor dimension at the taper portion (506) and back at the transition portion.

The present disclosure relates to gearboxes for aircraft gas turbine engines, in particular to arrangements for journal bearings such gearboxes, and to related methods of operating such gearboxes and gas turbine engines. Example embodiments include a gearbox for an aircraft gas turbine engine, the gearbox comprising: a sun gear; a plurality of planet gears surrounding and engaged with the sun gear; and a ring gear surrounding and engaged with the plurality of planet gears, each of the plurality of planet gears being rotatably mounted around a pin of a planet gear carrier with a journal bearing having an internal sliding surface on the planet gear and an external sliding surface on the pin.

A seal assembly includes a carbon seal that has a sealing surface. A seal seat has a sealing surface and is positioned for rotation relative to the carbon seal. A diamond-like carbon coating at least partially forms the sealing surface on the seal seat.

An apparatus is provided for a turbine engine. This turbine engine apparatus includes a journal bearing extending axially along and circumferentially about an axis. The journal bearing extends radially between a bearing inner side and a bearing outer side. The journal bearing includes a bore, a passage, a groove and a slot. The bore extends axially within the journal bearing and along the bearing inner side. The passage extends radially within the journal bearing and is fluidly coupled with the bore and the groove. The groove extends longitudinally within the journal bearing at the bearing outer side between a groove first end and a groove second end. At least a portion of the slot extends circumferentially about the axis within the journal bearing at the bearing outer side from the groove first end to the groove second end.

An assembly is provided for a turbine engine. This turbine engine assembly includes a journal bearing and a filter. The journal bearing has an internal bearing bore. The filter is arranged within the internal bearing bore. The filter includes a tubular filter element and a first end cap. The tubular filter element extends axially along an axis between a first end and a second end. A perforated portion of the tubular filter element is radially disposed away from the journal bearing by a cavity. The first end cap is mounted to the tubular filter element at the first end. The first end cap is sealed radially against the journal bearing by a first interference fit.

An apparatus is provided for a turbine engine. This turbine engine apparatus includes a journal bearing extending axially along and circumferentially about an axis. The journal bearing extends radially between an inner side and an outer side. The journal bearing includes a bore, a passage and a groove. The bore extends axially within the journal bearing and is formed by the inner side. The passage extends radially within the journal bearing and is fluidly coupled with the bore and the groove. The groove is arranged at the outer side. The groove extends longitudinally within the journal bearing between a first end and a second end. The groove extends axially within the journal bearing between a first side and a second side. An axial distance between the first side and the second side changes as the groove extends longitudinally between the first end and the second end.

A bearing housing for supporting a bearing of a gas turbine engine. The bearing housing comprises an annular body extending around an axis and having an oil inlet and an oil outlet. The bearing housing further comprises an oil manifold integrated into the annular body, the oil manifold having an inner oil channel defined in the annular body and extending circumferentially around the axis, the inner oil channel in fluid communication with the oil inlet and at least one oil jet directed towards the bearing.

An exhaust gas turbocharger having a hydrodynamic plain bearing or a hydrodynamic plain bearing, comprising a rotor (10) and a counter-bearing part (50) assigned to the rotor (10), wherein a rotor bearing surface (17.1, 17.2, 17.3) of the rotor (10) and a counter-surface of the counter-bearing part (50) face each other to form a hydrodynamic plain bearing, wherein the rotor bearing surface and/or the counterface, when cut along and through the axis of rotation (R) in sectional view, form(s) a continuous bearing contour forming at least two contour sections (44.1 to 44.3; 53.1 to 53.3) to provide hydrodynamic load capacities in both radial and axial directions, and wherein the counter-bearing part (50) is mounted in a bearing housing (60) or housing part. In order to be able to provide such an exhaust gas turbocharger with a compact and efficient bearing arrangement having a hydrodynamic plain bearing, wherein at the same time the hydrodynamic plain bearing can be easily mounted with a small number of parts, provision is made according to the invention that in that a preferably circumferential gap area (57) for forming a trapped oil film is formed between an outer contour of the counter-bearing part (50) and the bearing housing (60) or the housing part, wherein the gap area (57) is spatially connected to a lubricant guide channel (61), and in that the gap area (57) and the continuous bearing contour of the rotor (10) and/or of the counter-bearing part (50) overlap at least sectionally in the direction of the axis of rotation (R).