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 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 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 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: Reduce bearing loss due to lubricating oil using a rotary shaft; a journal bearing that is provided to the rotary shaft and that rotatably supports the rotary shaft; a flange part having an opposing surface part that is arranged so as to oppose a side surface part of the journal bearing with a gap therebetween in the axial direction in which the rotary shaft extends; and a recess part provided in the side surface part or the opposing surface part. In the projected area of the journal bearing in the axial direction, the area of a section including the recess part and not forming the gap is larger than the area in which the side surface part and the opposing surface part form the gap.

Abstract: An oil-drain device for a thrust bearing includes: a rotor shaft; a collar member mounted to an outer periphery of the rotor shaft; a thrust bearing supporting the rotor shaft in an axial direction; and an oil-drain space forming member defining an oil-drain space through which lubricant oil leaking from a sliding portion of the thrust bearing flows, between the thrust bearing and the oil-drain space forming member. The oil-drain space includes: an oil-drain channel defined between a first end surface of the thrust bearing and a first end surface of the oil-drain space forming member, surrounding the flange portion of the collar member; and an oil-drain port formed below the oil-drain channel, for discharging the lubricant oil flowing through the oil-drain channel outside the oil-drain space.

Abstract: The purpose of the invention is to reduce bearing loss due to lubricating oil. This invention comprises: a rotary shaft (14); a journal bearing (22) that is provided to the rotary shaft (14) and that rotatably supports the rotary shaft (14); a flange part (17b) having an opposing surface part (17bb) that is arranged so as to oppose a side surface part (22d) of the journal bearing (22) with a gap (D) therebetween in the axial direction in which the rotary shaft (14) extends; and a recess part (22e) provided in the side surface part (22d) or the opposing surface part (17bb). In the projected area of the journal bearing (22) in the axial direction, the area of a section including the recess part (22e) and not forming the gap (D) is larger than the area in which the side surface part (22d) and the opposing surface part (17bb) form the gap (D).

Abstract: An object is to provide a centrifugal compressor in which an axial force applied from a shrink-fit impeller to a sleeve section is ensured even if the sleeve section is separated from a clamp surface in an axial direction of an attachment hole, as well as a turbocharger provided with the centrifugal compressor and a method of producing the centrifugal compressor. An inner peripheral surface of an attachment hole formed on a hub includes a clamp surface and a diameter-widening surface, and an outer peripheral surface of a sleeve section includes a diameter-reducing surface.

Abstract: An oil-drain device for a thrust bearing includes: a rotor shaft; a collar member mounted to an outer periphery of the rotor shaft; a thrust bearing supporting the rotor shaft in an axial direction; and an oil-drain space forming member defining an oil-drain space through which lubricant oil leaking from a sliding portion of the thrust bearing flows, between the thrust bearing and the oil-drain space forming member. The oil-drain space includes: an oil-drain channel defined between a first end surface of the thrust bearing and a first end surface of the oil-drain space forming member, surrounding the flange portion of the collar member; and an oil-drain port formed below the oil-drain channel, for discharging the lubricant oil flowing through the oil-drain channel outside the oil-drain space.

Abstract: An object is to provide a centrifugal compressor in which an axial force applied from a shrink-fit impeller to a sleeve section is ensured even if the sleeve section is separated from a clamp surface in an axial direction of an attachment hole, as well as a turbocharger provided with the centrifugal compressor and a method of producing the centrifugal compressor. An inner peripheral surface of an attachment hole formed on a hub includes a clamp surface and a diameter-widening surface, and an outer peripheral surface of a sleeve section includes a diameter-reducing surface.