Abstract: A gas bearing device is a gas bearing device using a gas as a working fluid, including: a rotational shaft; a housing where the rotational shaft penetrates; an annular top foil disposed inside the housing and surrounding an outer periphery of the rotational shaft; a back spring disposed between the top foil and the housing, and having a plurality of crests contacting the top foil and a plurality of valleys contacting the housing; and a pair of snap rings fitted in shaft holes where the rotational shaft of the housing penetrates, and configured to restrict movement of the back spring in an axial direction of the rotational shaft. The gas bearing device has a turning groove inclined with respect to an axis of the rotational shaft, in at least one of the pair of snap rings or in a region of the rotational shaft facing at least one of the pair of snap rings.

Abstract: A gas bearing device is a gas bearing device for rotatably supporting a rotational shaft by using a gas as a working fluid, including: a housing where the rotational shaft penetrates; an annular top foil disposed inside the housing and surrounding an outer periphery of the rotational shaft; a back spring disposed between the top foil and the housing, and having a plurality of crests contacting the top foil and a plurality of valleys contacting the housing; and a pair of snap rings fitted in shaft holes where the rotational shaft of the housing penetrates, and configured to restrict movement of the back spring in an axial direction of the rotational shaft. An inner peripheral surface of each of the pair of snap rings has self-lubricating properties.

Abstract: A bearing condition monitoring device is a bearing condition monitoring device for monitoring a condition of a thrust bearing for holding a rotational shaft in a thrust direction. The bearing condition monitoring device includes a first temperature sensor for measuring a temperature of the thrust bearing, and an arithmetic device for counting a frequency at which an evaluation index of a thrust load on the basis of a measurement value by the first temperature sensor exceeds an allowable value, and for outputting an abnormality in the condition of the thrust bearing if the counted frequency exceeds a threshold. The arithmetic device may count, as the frequency, only a case where a state in which the thrust load exceeds an upper limit load continues for not less than a predetermined time.

Abstract: A bearing device is configured to rotatably support a rotational shaft of a rotating machine and includes: a semi-floating bearing supported by a bearing housing; and an anti-rotation pin fixed to the bearing housing and having an insertion portion inserted from an outer peripheral side into an insertion hole formed on an outer surface of the semi-floating bearing. At least one of the insertion hole or the insertion portion has at least one protrusion that protrudes toward the other of the insertion hole or the insertion portion in a plan view perpendicular to an axis of the rotational shaft.

Abstract: A thrust bearing device includes: a thrust collar fitted with a drive shaft, the thrust collar including a flange portion extending radially outward of the drive shaft; and a thrust member penetrated by the thrust collar and including a pad portion in a region facing the flange portion. The pad portion includes: a plurality of land portions which are parallel to a plane orthogonal an axis of the drive shaft and are disposed at intervals in a circumferential direction of the drive shaft; and tapered portions each of which is disposed between adjacent land portions among the plurality of land portions, joined via a step to a boundary of one land portion in the circumferential direction of the drive shaft, and joined continuously to a boundary of another land portion. Each of the land portions has a circumferential groove which is longer in the circumferential direction than in a radial direction of the drive shaft.

Abstract: A thrust bearing device is provided with: a rotational shaft; a collar member fitted to the rotational shaft and having a first thrust surface; and a thrust member having an insertion hole into which the rotational shaft is inserted and a second thrust surface which is disposed around the insertion hole and faces the first thrust surface of the collar member. The first thrust surface is configured to be inclined with respect to a plane perpendicular to an axis of the rotational shaft so that a distance between the first thrust surface and the second thrust surface periodically increases and decreases with rotation of the rotational shaft.

Abstract: A rotary electric machine includes a housing, a stator disposed in the housing, and at least two support members disposed in at least two different parts, respectively, in an axial direction of the stator between the housing and an outer circumferential surface of the stator, the at least two support members supporting the stator against the housing. The at least two support members, the housing, and the outer circumferential surface of the stator form a space.

Abstract: A turbocharger includes a rolling bearing including at least one rolling element for rotatably supporting a rotational shaft, a bearing support cylinder located on a radially outer side relative to the rolling bearing, for supporting the rolling bearing, and a housing located on the radially outer side relative to the bearing support cylinder, for covering a circumference of the bearing support cylinder. Between an outer circumferential surface of the bearing support cylinder and an inner circumferential surface of the housing, a gap for forming an oil film by inflow of lubricant oil is provided. At least one of the outer circumferential surface of the bearing support cylinder and the inner circumferential surface of the housing includes an oil film holding portion for suppressing outflow of the lubricant oil from the gap.

Abstract: A bearing device according to an embodiment is a bearing device for rotatably supporting a rotational shaft, the device including at least one rolling bearing which includes an inner race fixed to the rotational shaft, a rolling element, and an outer race for rotatably holding the rolling element with the inner race, and a casing for housing the rolling bearing, the casing including a plurality of first oil supply holes formed at intervals in a circumferential direction for supplying lubricant oil to a first gap between the rolling bearing and an inner circumferential surface of the casing. Each of the plurality of first oil supply holes satisfies: ?·d1·?1<?·d12/4,??(a) where d1 is a diameter of an outlet opening of the first oil supply hole, and ?1 is a space of the first gap.

Abstract: A forced induction device (100) includes: a rotor (1) which includes a turbine side shaft portion (11), a compressor side shaft portion (12), and a connection shaft portion (13) connecting these to each other; a turbine side bearing (5) which supports the turbine side shaft portion (11); and a compressor side bearing (6) which supports the compressor side shaft portion (12). A rigidity of the connection shaft portion (13) is lower than that of the turbine side shaft portion (11) and the compressor side shaft portion (12) so that a node in a mode shape at each critical speed involving with an operating rotational speed region of the rotor (1) is located between the turbine side bearing (5) and the compressor side bearing (6).

Abstract: A compressor wheel device comprises a compressor wheel attached to a rotary shaft and a thrust collar attached to the rotary shaft at a back surface of the compressor wheel. The compressor wheel includes: a wheel body part with a hub and at least one blade provided on an outer peripheral surface of the hub; and a sleeve part having a cylindrical shape projecting along an axis direction from a back surface of the hub and having an outer peripheral surface on which a sealing groove extending along a peripheral direction is formed. The thrust collar has a circular plate-like shape including: one surface including an abutting surface abutting on an end surface of the sleeve part and extending along a radial direction; and the other surface including a slidably-contacting surface slidably contacting a thrust bearing supporting the rotary shaft in a thrust direction and extending along the radial direction.

Abstract: A thrust bearing device is provided with: a rotational shaft; a collar member fitted to the rotational shaft and having a first thrust surface; and a thrust member having an insertion hole into which the rotational shaft is inserted and a second thrust surface which is disposed around the insertion hole and faces the first thrust surface of the collar member. The first thrust surface is configured to be inclined with respect to a plane perpendicular to an axis of the rotational shaft so that a distance between the first thrust surface and the second thrust surface periodically increases and decreases with rotation of the rotational shaft.

Abstract: A floating bush bearing configured to support a rotational shaft rotatably includes: a floating bush body part formed to have a cylindrical shape having an insertion hole through which the rotational shaft is inserted. The floating bush body part includes: an inner peripheral surface; an outer peripheral surface having a greater width dimension than the inner peripheral surface in an axial direction of the floating bush body part; and an axial end surface which connects an end of the inner peripheral surface and an end of the outer peripheral surface, the axial end surface including a vertical surface extending along a direction orthogonal to the axial direction from the end of the outer peripheral surface toward a radially inner side and an oblique surface extending from a radially inner end of the vertical surface toward the end of the inner peripheral surface.

Abstract: A turbocharger (1A) includes a rotary shaft (2), a journal hearing (5A), and a bearing housing (10). The journal hearing (5A) includes load support surfaces (14 and 15), a first gap forming portion (F1), and a second gap forming portion (F2). The first gap forming portion (F1) firms a first gap (101) in a radial direction between the load support surfaces (14 and 15) adjacent to each other in a direction of a central axis (O). The second gap forming portion (F2) forms a second gap (102) smaller than the first gap in the radial direction between the load support surfaces (14 and 15) adjacent to each other in the direction of the central axis (O).

Abstract: A bearing device according to an embodiment is a bearing device for rotatably supporting a rotational shaft, the device including at least one rolling bearing which includes an inner race fixed to the rotational shaft, a rolling element, and an outer race for rotatably holding the rolling element with the inner race, and a casing for housing the rolling bearing, the casing including a plurality of first oil supply holes formed at intervals in a circumferential direction for supplying lubricant oil to a first gap between the rolling bearing and an inner circumferential surface of the casing. Each of the plurality of first oil supply holes satisfies: ?·d1·?1<?·d12/4 ??(a) , where d1 is a diameter of an outlet opening of the first oil supply hole, and ?1 is a space of the first gap.

Abstract: A bearing condition monitoring device is a bearing condition monitoring device for monitoring a condition of a thrust bearing for holding a rotational shaft in a thrust direction. The bearing condition monitoring device includes a first temperature sensor for measuring a temperature of the thrust bearing, and an arithmetic device for counting a frequency at which an evaluation index of a thrust load on the basis of a measurement value by the first temperature sensor exceeds an allowable value, and for outputting an abnormality in the condition of the thrust bearing if the counted frequency exceeds a threshold. The arithmetic device may count, as the frequency, only a case where a state in which the thrust load exceeds an upper limit load continues for not less than a predetermined time.

Abstract: A compressor wheel device comprises a compressor wheel attached to a rotary shaft and a thrust collar attached to the rotary shaft at a back surface of the compressor wheel. The compressor wheel includes: a wheel body part with a hub and at least one blade provided on an outer peripheral surface of the hub; and a sleeve part having a cylindrical shape projecting along an axis direction from a back surface of the hub and having an outer peripheral surface on which a sealing groove extending along a peripheral direction is formed. The thrust collar has a circular plate-like shape including: one surface including an abutting surface abutting on an end surface of the sleeve part and extending along a radial direction; and the other surface including a slidably-contacting surface slidably contacting a thrust bearing supporting the rotary shaft in a thrust direction and extending along the radial direction.

Abstract: A floating bush bearing configured to support a rotational shaft rotatably includes: a floating bush body part formed to have a cylindrical shape having an insertion hole through which the rotational shaft is inserted. The floating bush body part includes: an inner peripheral surface; an outer peripheral surface having a greater width dimension than the inner peripheral surface in an axial direction of the floating bush body part; and an axial end surface which connects an end of the inner peripheral surface and an end of the outer peripheral surface, the axial end surface including a vertical surface extending along a direction orthogonal to the axial direction from the end of the outer peripheral surface toward a radially inner side and an oblique surface extending from a radially inner end of the vertical surface toward the end of the inner peripheral surface.

Abstract: A turbocharger includes a rolling bearing including at least one rolling element for rotatably supporting a rotational shaft, a bearing support cylinder located on a radially outer side relative to the rolling bearing, for supporting the rolling bearing, and a housing located on the radially outer side relative to the bearing support cylinder, for covering a circumference of the bearing support cylinder. Between an outer circumferential surface of the bearing support cylinder and an inner circumferential surface of the housing, a gap for forming an oil film by inflow of lubricant oil is provided. At least one of the outer circumferential surface of the bearing support cylinder and the inner circumferential surface of the housing includes an oil film holding portion for suppressing outflow of the lubricant oil from the gap.

Abstract: A turbocharger includes a rotor shaft that is rotationally driven, a compressor impeller attached to the rotor shaft, and a cylindrical bearing portion that includes an inner cylinder and an outer cylinder, and that supports the rotor shaft in a rotatable manner. A first damping portion is provided between an axial first end portion of the inner cylinder and an axial first end portion of the outer cylinder, and an axial second end portion of the inner cylinder is connected with an axial second end portion of the outer cylinder. A second damping portion is provided between a housing and the axial second end portion. The housing and the bearing portion are fixed by a flange portion provided at the first end portion of the outer cylinder in such a manner as to restrict movement of the flange portion in a radial direction and in an axial direction.