A bearing includes a thrust gas bearing attached to a journal bearing and two or more converging-diverging orifices defined in a surface of at least one of the thrust gas bearing and the journal bearing. The converging-diverging orifices supply at least one pressurized gas to an interior of the bearing. Hydrodynamic lifting grooves are provided on the faces of the thrust gas bearing and the journal bearing and provide improved load capacity and sealing capabilities. Control over the ratios of the pressurized gases provides for additional sealing capabilities and reduced leakage. A metal mesh damper provides increased damping of the gas bearing.

A motor includes a bearing having a rolling member disposed between an inner ring and an outer ring, a spring connected to the outer ring, and a pusher connected to the spring and configured to move to a first position spaced apart from the inner ring by the spring. The pusher is further configured to move to a second position at which friction with the inner ring is caused by a pressure of air. The inner ring is spaced apart from the rotating shaft by a gap between the inner ring and the rotating shaft when the pusher is at the second position.

Each of foils (22) includes: a top foil portion (22a) including a bearing surface (S); and a back foil portion (22b), which is formed on an upstream side of the top foil portion (22a), and is arranged so as to overlap behind the top foil portion (22a) of the adjacent foil (22) (on a side opposite to the bearing surface (S)). An angle (E) covering a radially inner end of an overlapping portion (P) between the adjacent foils (22) is smaller than an angle (D) covering a radially outer end of the overlapping portion (P).

A variable stiffness damper system including an inner spring positioned between a first wall and a second wall, in which the inner spring includes a first member and a second member each coupled together at a distal end by an inner bumper. The first member and the second member are each contoured toward one another. The first member, the second member, and the inner bumper form a cavity therebetween. An outer spring is positioned between the inner spring and the first wall or the second wall. The outer spring includes a spring arm contoured toward the inner spring. The outer spring includes an outer bumper positioned between the inner bumper and the first wall or the second wall. The inner bumper and the outer bumper are selectively couplable to one another based on a load applied to the damper system.

A power module includes a turbine arranged along a rotation axis, an interconnect shaft fixed in rotation relative to the turbine, and a compressor with a regenerative compressor wheel. The regenerative compressor wheel is fixed in rotation relative to the interconnect shaft supported for rotation with the turbine about the rotation axis. Generator arrangements, unmanned aerial vehicles, and methods of generating electrical power are also described.

A propulsion system includes a drive shaft movable about an axis of rotation, a fan, a fan shaft that drives the fan, and a reduction device coupling the drive shaft and the fan shaft. The reduction device has first and second reduction stages and includes a sun gear, centered on the axis and driven by the drive shaft, a ring gear that is coaxial with the sun gear and that drives the fan shaft about the axis, and planet gears distributed circumferentially about the axis between the sun gear and the ring gear. Each planet gear includes a first portion meshed with the sun gear and a second portion meshed with the ring gear. A diameter of the first portion is different from a diameter of the second portion, and the first portion of the planet gears extend between the second portion of the planet gears and the fan.

The invention relates to a turbocharger for an internal combustion engine, comprising a housing (1) with an exhaust-gas-side and an air-side turbine blade (2), a shaft (3) connecting the turbine blades, and at least one radially acting rotary bearing for mounting the shaft (3), wherein the rotary bearing is designed as a hydrodynamic floating bearing, wherein a lubricant flows in a completely surrounding bearing gap (8) of the rotary bearing in the direction of rotation and has a local lubricant pressure, the bearing gap (8) has a contouring (10, 11, 10a, 11a, 12, 13, 14, 15) due to which the at least two local maxima (PM1, PM2) of the lubricant pressure are formed at two defined angular positions (W1, W2) in the direction of rotation.

A gas turbine propulsion system includes a shroud that defines a fluid flow path. A gas turbine engine in the fluid flow path includes a compressor, a combustor downstream from the compressor, and a turbine downstream from the combustor. An electric generator in the fluid flow path includes a rotor coaxially aligned with the turbine. A propulsor is upstream from the gas turbine engine, and an electric motor is operably coupled to the propulsor to rotate the propulsor. The propulsor is rotationally isolated from the gas turbine engine so that the propulsor rotates independently from operation of the gas turbine engine.

Each of foils (22) includes: a top foil portion (22a) including a bearing surface (S); and a back foil portion (22b), which is formed on an upstream side of the top foil portion (22a), and is arranged so as to overlap behind the top foil portion (22a) of the adjacent foil (22) (on a side opposite to the bearing surface (S)). An angle (E) covering a radially inner end of an overlapping portion (P) between the adjacent foils (22) is smaller than an angle (D) covering a radially outer end of the overlapping portion (P).

The invention relates to 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 of the rotor (10) and a counterface of the counter-bearing part (50) face each other to form the hydrodynamic plain bearing in the form of a combined journal—thrust bearing, having a continuous hydrodynamically load bearing gap formed between the rotor bearing surface and the counterface, wherein the rotor bearing surface and/or the counterface, when cut longitudinally and through the axis of rotation (R) in sectional view, form(s) a bearing contour forming merging contour sections (17.1 to 17.3; 44.1 to 44.3; 53.1 to 53.3) to generate hydrodynamic load capacities in both the radial and the axial direction, wherein a contour section (17.3; 44.3; 53.3) in sectional view in a first bearing area forms a linear section that is part of a, in particular cylindrical or partially cylindrical, bearing section rotating at least sectionally about the axis of rotation (R), wherein a further contour section (17.1; 44.1; 53.1), in sectional view in a second bearing area, forms a further linear section, which is part of a further bearing area rotating at least sectionally about the axis of rotation (R), wherein this further linear section forms an angle with the axis of rotation (R), and wherein the first and the second bearing area merge via a transition section. According to the invention, a friction-optimized bearing system is to be created, which is easy to manufacture and ensures a reliable and effective bearing arrangement even under highly dynamic loads. According to the invention, this is achieved by the further linear section forming an angle in the range from >30° to <90° with the axis of rotation (R).