Abstract: A centrifugal compressor includes an impeller rotatably disposed and having a plurality of first blades and a shroud cover disposed on a leading edge side of the first blades partially in a rotational axis direction of the impeller and connecting the first blades circumferentially adjacent to each other. The shroud cover is shaped such that a position of at least one of an upstream edge or a downstream edge of the shroud cover in the rotational axis direction changes along a circumferential direction of the shroud cover.

Abstract: An impeller for a centrifugal turbomachine includes: a hub having a small-diameter portion positioned at a first end portion in an axial direction and a large-diameter portion positioned at a second end portion in the axial direction, the large-diameter portion having a greater diameter than the small-diameter portion; and a blade having a first edge positioned at an axial-directional position of the small-diameter portion and a second edge positioned at an axial-directional position of the large-diameter portion, the blade being disposed on an outer peripheral surface of the hub. The impeller is configured such that, when a first radial-directional cross section is a cross section of the impeller at an axial-directional position passing a tip of the first edge, at least a part of the first radial-directional cross section in a blade-height range of 50% or more is inclined downstream in a rotational direction of the impeller with respect to a radial direction.

Abstract: Provided is a supercharger (11) comprising: a hollow housing (15); a rotating shaft (14) rotatably supported by the housing (15); a turbine (12) provided at one axial end of the rotating shaft (14); and a compressor (13) provided at the other axial end of the rotating shaft (14). A threaded section (41) and a circular column section (42) are axially arranged at the other end of the rotating shaft (14). A threaded hole (43) with which the threaded section (41) is engaged and a fitting hole (44) in which the circular column section (42) is fitted are axially arranged in the compressor (13). The axial length of the circular column section (42) and the fitting hole (44) is set to be greater than the axial length of the threaded section (41) and the threaded hole (43).

Abstract: A compressor comprises: a rotor including a hub and a blade provided on an outer peripheral surface of the hub; and a casing surrounding the rotor so as to face a tip of the blade across a gap. Provided that the gap between the tip of the blade and the casing has a size t0 at a leading edge of the blade, the gap between the tip of the blade and the casing has a size larger than t0 in at least a partial range downstream of the leading edge in an axial direction of the rotor.

Abstract: The present invention is provided with: an annular hub 7 having a circularly formed axial cross-section; a plurality of first blades 8 that are arranged on the outer circumferential surface of the hub 7; and a plurality of second blades 9 that are arranged closer to the downstream-side in the flow direction of fluid than the rear edges 8b of the first blades 8, in the outer circumferential surface of the hub 7, wherein the number of the second blades 9 is less than a double that of the first blades 8.

Abstract: A compressor scroll (1A) is provided with: a scroll-flow-path formation part (8A) that forms a scroll flow path; and an outlet-flow-path formation part (9) that is connected to a winding-end section (11) of a scroll flow path (8a) and that forms an outlet flow path (9a) extending in a direction tangential to a circle around an axis (O), wherein, at least at the winding-end section (11) in an area where a winding-start section (10) intersects with the winding-end section (11), the scroll-flow-path formation part (8A) is provided with a bulging part (15A) that bulges the scroll flow path in the radial direction toward the side where the winding-start section (10) is present.

Abstract: The present invention provides a method for producing a casing for a compressor, the method including an intake-side casing molding process of molding an intake portion and a first main body portion of a scroll portion by integral molding of resin; an impeller-side casing molding process of integrally molding a second main body portion of the scroll portion and a diffuser portion by a resin molding metal mold used in the intake-side casing molding process; a die sliding process of combining the intake portion and the first main body portion which have been integrally molded, and the second main body portion and the diffuser portion which have been integrally molded, by slide of the resin molding metal mold; and a secondary molding process of joining the intake portion and the first main body portion, and the second main body portion and the diffuser portion combined with each other by resin.

Abstract: A centrifugal compressor includes an impeller and a casing. The casing includes a scroll part forming a scroll flow passage on a radially outer side of the impeller and a diffuser part forming a diffuser flow passage for supplying the scroll flow passage with compressed air compressed by the impeller. The diffuser part includes: a first diffuser portion belonging to a first angular range including an angular position of a tongue section of the scroll part, of an angular range in a circumferential direction of the impeller; and a second diffuser portion belonging to a second angular range downstream of the first angular range in a flow direction of the scroll flow passage, of the angular range in the circumferential direction of the impeller, the second diffuser portion having an outer radius R2 which is defined along a reference circle centered at a rotational center of the impeller.

Abstract: A bend pipe for supplying a fluid to a fluid machine or discharging the fluid from the fluid machine, wherein, provided that: a line including a pipe axial center line of an inlet pipe portion and an extension line thereof is defined as a line L; a line including a pipe axial line of an outlet pipe portion and an extension line thereof is defined as a line M; and a direction parallel to an intersection line formed by a plane orthogonal to the line M and a plane orthogonal to the line M is defined as a direction I, and when, as seen from the direction I, a side of the line M on which the inlet pipe portion exists is defined as a front side and a side of the line M on which the inlet pipe portion does not exist is defined as a back side, a side surface on an outer side with respect to a bend direction of a bend pipe portion includes an outer inclined surface on the back side of the line M, the outer inclined surface being inclined so that a distance from the line M decreases toward a downstream side.

Abstract: A scroll casing forms a scroll flow passage of a centrifugal compressor, and, provided that, in a cross section of the scroll flow passage, Eo is an outer end of the scroll flow passage in a radial direction of the centrifugal compressor, Ef is a front end of the scroll flow passage in an axial direction of the centrifugal compressor, and Mw is a middle point of a maximum flow-passage width Wmax of the scroll flow passage in the radial direction, a flow passage height H of the scroll flow passage in the axial direction gradually increases from a position of the outer end Eo to a position of the front end Ef with respect to the radial direction, and the scroll flow passage has a recirculation flow suppressing cross section in which the front end Ef is disposed on an inner side, in the radial direction, of the middle point Mw, in a section disposed at least partially in a region closer to a scroll start than a connection position of the scroll start and a scroll end.

Abstract: A compressor impeller includes: a hub; and a blade group including a plurality of blades arranged along a circumferential direction on an outer peripheral surface of the hub, the blade group being configured such that hub-side ends of leading edges of the respective blades are aligned on the same circle. The plurality of blades include at least one first blade and at least one second blade having a different shape from the at least one first blade. When comparing a blade angle of a leading edge of the at least one first blade to a blade angle of a leading edge of the at least one second blade at the same position in a radial direction of the compressor impeller, the blade angle of the leading edge of the at least one first blade is different from the blade angle of the leading edge of the at least one second blade, at least in a partial range in the radial direction of the compressor impeller.

Abstract: A scroll casing forms a scroll flow passage of a centrifugal compressor, and provided that, in a cross section of the scroll flow passage, pEi is an inner end of the scroll flow passage in a radial direction of the centrifugal compressor, and Mh is a middle point of a maximum flow-passage height Hmax of the scroll flow passage in the axial direction of the centrifugal compressor, the scroll flow passage has a separation suppressing cross section in which the inner end Ei is disposed on an inner side, in the radial direction, of a diffuser outlet, and the inner end Ei is disposed on a back side, in the axial direction, of the middle point Mh, in a section disposed at least partially in an upstream region of a connection position of a scroll start and a scroll end.

Abstract: A pipe connection structure according to an embodiment of the present invention includes: two inlet pipes through which a gas is capable of flowing; a connection pipe to which respective outlet-side end portions of the two inlet pipes are connected at a distance; and an outlet pipe connected to the connection pipe at an opposite side to a side where the two inlet pipes are connected to the connection pipe, the outlet pipe being capable of being in communication with the two inlet pipes via a space section inside the connection pipe. The two inlet pipes include a first inlet pipe disposed on a first side and a second inlet pipe disposed on a second side, in a width direction of the connection pipe, across a middle of connection positions of the two inlet pipes to the connection pipe. The outlet pipe is connected to a position offset toward the second side in the width direction of the connection pipe.

Abstract: A rotary machine satisfies at least one of Dr1<Dh1?Dr2 or Dc1?Dt1>Dc2. Dr1, Dh1, Dr2, Dc1, Dt1, and Dc2 are distances from a rotational center axis of a hub to an upstream end of a first blade-facing surface facing a hub-side end surface of a variable blade, an upstream end of the hub-side end surface when the blade angle is maximum, a downstream end of a first outer peripheral surface adjacent to an upstream side of the blade-facing surface, an upstream end of a second blade-facing surface facing a tip-side end surface of the variable blade, an upstream end of the tip-side end surface when the blade angle is minimum, and a downstream end of a first inner peripheral surface adjacent to an upstream side of the second blade-facing surface, respectively.

Abstract: A rotary machine comprises a hub including: a blade-facing hub portion including a first blade-facing surface which faces a spherical hub-side end surface of a variable blade and which has a first spherical region having a spherical shape; an upstream hub portion disposed upstream of the blade-facing hub portion in an axial direction of the hub and having a first outer-peripheral surface being adjacent to the first blade-facing surface in the axial direction; and a downstream hub portion disposed downstream of the blade-facing hub portion in the axial direction and having a second outer peripheral surface being adjacent to the first blade-facing surface in the axial direction.

Abstract: An impeller for a centrifugal compressor is characterized in that a shroud side of a front edge 7a of a splitter blade 7 is disposed so as to be displaced toward a negative-pressure surface Sb of a full blade 5F from a position equidistant from the full blades 5R and 5F in a circumferential direction such that a blade-end leakage vortex generated during a high flow rate which occurs from a blade-end clearance between the tip of the full blade 5F and a shroud toward the portion of the front edge 7a of the splitter blade 7 gets over the front edge 7a of the splitter blade 7.

Abstract: An axial cross-sectional shape of a scroll flow path 13 is a roughly circular shape, a diffuser outlet connected to the roughly circular shape is shifted to a position which is closer to a circle center than to a position of a tangent line to the circular shape and which does not reach the circle center, the circular shape is formed from a scroll chamber 30 which juts out in the axial direction relative to the position of the diffuser outlet 11a and a shift chamber 32 that forms a remainder of the roughly circular shape in a direction opposite to the scroll chamber 30, and the shift chamber 32 is at least formed on the scroll flow path 13 of a winding end portion 19 in a circumferential direction of a spiral.

Abstract: A cooling structure for a bearing housing for a turbocharger is provided. The cooling structure is configured so that the cooling structure has improved productivity, the occurrence of heat soak-back is reduced, and the cooling structure has improved cooling performance. The cooling structure cools both a bearing housing 13 and a bearing 52 by cooling water flowing through an annular cooling water path 13f formed in the bearing housing 13, and is provided with: a water path inlet 13h for supplying the cooling water and a water path outlet 13j for discharging the cooling water, which are provided in the bearing housing 13 to communicate with the annular cooling water path 13f; and a partial partition 14a in the bearing housing 13 to partially close a water path which forms the shortest route between the water path inlet 13h and the water path outlet 13j.

Abstract: A scroll structure of a centrifugal compressor 1 having a spirally formed scroll passage 13. The scroll passage 13 includes: a flat connecting portion A at a flow passage joint 23 where a scroll start and a scroll end of the scroll passage 13 meet, this flat connecting portion having a flat cross-sectional shape with a same height as that of an outlet passage of a diffuser; and a transition part 21 where the flat cross-sectional shape of the flat connecting portion A gradually changes back to a circular cross-sectional shape along a circumferential direction.

Abstract: In a scroll shape of a centrifugal compressor, an enlargement rate of a ratio A/R of a cross-sectional area A of a scroll portion 12 to a radius R from an axis L1 of a compressor impeller 3 to a centroid P0 of a cross section of the scroll portion is reduced from a winding start to a winding end of the scroll portion.