Abstract: A position detection device includes: a first group including N (a multiple of 3) first magnetic sensors facing a magnet that rotates in synchronization with a rotation shaft of a motor and arranged at intervals along a rotation direction of the magnet, and a second group including N second magnetic sensors arranged opposite respectively to the N first magnetic sensors across the rotation shaft in a radial direction of the magnet; and a signal processing device processing output signals respectively output from the first and second magnetic sensors. The signal processing device executes averaging processing of generating N average signals by averaging an output signal of the first magnetic sensor and an output signal of the second magnetic sensor arranged at the position opposite to the first magnetic sensor across the rotation shaft, and estimation processing of estimating a rotational position of the motor based on the N average signals.

Abstract: A thermal device according to the present disclosure includes a ceramic container, a fluid, and a sealing portion. The container includes an internal space, an opening portion connected to the internal space, and a communication path configured to connect the internal space and the opening portion. The fluid is located in the internal space. The sealing portion blocks the opening portion. The sealing portion includes a core portion and a flange connected to the core portion. The flange is bonded to the container around the opening portion. The core portion is located inside the opening portion. A portion of the core portion is in contact with the wall surface of the opening portion.

Abstract: An optical combiner includes: a plurality of first input optical fibers that each include a core; a bridge fiber that includes a bridge input surface connected to the cores of the plurality of first input optical fibers, a diameter reduction portion having a diameter that decreases away from the bridge input surface along an optical axis of the optical combiner, and a bridge output surface located opposite to the bridge input surface along the optical axis; an intermediate optical fiber that includes a core connected to the bridge output surface of the bridge fiber; a second input optical fiber that includes a core; and an output optical fiber that includes a first optical waveguide connected to the core of the intermediate optical fiber, and a second optical waveguide connected to the core of the second input optical fiber.

Abstract: One aspect of a position estimation method of the present invention includes: a learning step of acquiring learning data necessary for estimation of a rotational position of a rotor on the basis of an input sensor signal; and a position estimation step of estimating the rotational position of the rotor on the basis of the input sensor signal and the learning data. The learning step is performed, thereby acquiring, as the learning data, data indicating the correspondence relationship between a segment number associated with a section included in each of a plurality of quadrants and a pole pair number representing a pole pair position. The position estimation step is performed, thereby determining an initial position of the rotor on the basis of the input sensor signal and the learning data.

Abstract: The present invention causes a holder to hold a plane mirror without causing damage to a reflection layer. Provided is a head-up display comprising a housing, a display device that emits display light, a plane mirror that reflects the display light, and a holder that holds the plane mirror, wherein the plane mirror has a base material, and a reflection layer provided on the base material and including a resin film, and the holder abuts on a portion of the base material in which the reflection layer is not provided.

Abstract: An impeller of a centrifugal compressor is an impeller 5 of a centrifugal compressor, that is, a compressor impeller 5 and includes a hub, at least one airfoil portion erected on a hub surface of the hub, and a first fillet. The at least one airfoil portion has a trailing edge configured such that a distance between the trailing edge and an axis of the centrifugal compressor increases with increasing distance from a back surface of the hub. The first fillet is formed on a radially outer side of an outer peripheral surface of a back plate portion forming a back surface portion of the hub. The first fillet connects the outer peripheral surface of the back plate portion and the trailing edge of the at least one airfoil portion.

Abstract: A compressor housing includes: when an intake side in an axial direction of the centrifugal compressor is defined as a front side, and a side opposite to the intake side in the axial direction is defined as a rear side, a shroud surface including a surface facing a tip of an impeller blade of the impeller with a predetermined gap; a front-side inner peripheral surface formed on the front side of the shroud surface in the axial direction and positioned on an outer side in a radial direction than a front end of the shroud surface; and plurality of grooves formed in the front-side inner peripheral surface at intervals in a circumferential direction wherein each of the plurality of grooves includes: an inclined portion whose depth gradually increases toward a rotation direction of the impeller; and a stepped portion formed at a downstream end of the inclined portion in the rotation direction.

Abstract: A compressor includes: a shroud surface; a front-side inner peripheral surface formed on a front side of the shroud surface in the axial direction and disposed outward of a front end of the shroud surface in the radial direction; and at least one projection protruding from the front-side inner peripheral surface inward in the radial direction. A rear end of the at least one projection is configured to be connected to the front end of the shroud surface. The at least one projection is formed in a plate shape, and in a cross-sectional view along an axis of the impeller, has an inclined front edge extending obliquely to the axis of the impeller from a front end of the projection toward a rear side.

Abstract: An impeller of a centrifugal compressor includes: a hub; and at least one blade disposed on a hub surface of the hub. A hub-side end of a trailing edge of the at least one blade is located radially outward of an outer peripheral portion of the hub, and is located on either of a first line extending radially outward from the hub surface of the hub or a second line extending radially outward from a back surface of the hub.

Abstract: A compressor housing internally forms: an inlet passage with an inflow port formed in a shroud surface; an outlet passage with an outflow port formed in an introduction surface formed on a front side of a shroud surface; and a recirculation passage connecting the inlet passage and the outlet passage. An intake air introduction portion of the compressor housing has: a front-side surface defining a front side in the outlet passage; a rear-side surface defining a rear side in the outlet passage; and a front-side introduction surface formed on the front side relative to the outflow port on the introduction surface. Each of the front-side surface, the rear-side surface, and the front-side introduction surface is inclined to the rear side from an outer side toward an inner side in a radial direction, the rear-side surface includes a convex curved portion, and the front-side introduction surface includes an introduction surface-side convex curved portion.

Abstract: A surge suppression device for suppressing surge in an exhaust turbine-type turbocharger includes: a high-pressure tank configured to accumulate high-pressure gas with a higher pressure than atmospheric pressure; a high-pressure gas injection line connecting the high-pressure tank and an upstream intake passage on an upstream side of a compressor of the turbocharger; an on-off valve configured to open and close the high-pressure gas injection line; and a control device configured to control the on-off valve on the basis of a relationship between a pressure ratio of the compressor of the turbocharger and an intake flow rate.

Abstract: A turbine shaft used for a turbocharger including a turbine and a compressor includes a turbine impeller, and a rotor shaft joined on one end side to the turbine impeller. The rotor shaft includes a fitting region configured to fit with a compressor impeller of the compressor by inserting the other end side of the rotor shaft into a through hole formed in the compressor impeller, a fastening region formed between the fitting region and the other end side of the rotor shaft, and configured to allow fastening by a fastening part, and a tapered part having a maximum outer diameter at a position closest to the turbine impeller in the fitting region and formed such that an outer diameter of the rotor shaft decreases from the position closest to the turbine impeller toward a tip side of the compressor impeller.

Abstract: An impeller of a centrifugal compressor is an impeller 5 of a centrifugal compressor, that is, a compressor impeller 5 and includes a hub, at least one airfoil portion erected on a hub surface of the hub, and a first fillet. The at least one airfoil portion has a trailing edge configured such that a distance between the trailing edge and an axis of the centrifugal compressor increases with increasing distance from a back surface of the hub. The first fillet is formed on a radially outer side of an outer peripheral surface of a back plate portion forming a back surface portion of the hub. The first fillet connects the outer peripheral surface of the back plate portion and the trailing edge of the at least one airfoil portion.

Abstract: In a centrifugal compressor including an impeller rotatably disposed in a housing, the housing includes a shroud wall and a hub wall, which define a diffuser passage communicating with an outlet of the impeller. The diffuser flow passage includes a pinched part configured such that the shroud wall is closer to the hub wall radially outward of the centrifugal compressor from the outlet of the impeller, and a parallel part communicating with the pinched part on a radially outer side of the centrifugal compressor than the pinched part, the parallel part being configured such that the shroud wall and the hub wall are parallel to each other. The shroud wall has a surface facing the impeller and the hub wall, the surface having a cross-sectional shape where a tangent line exists at any position in a cross-section including an axis of the impeller.

Abstract: A turbomachinery according to an embodiment includes an impeller including at least one blade, and a casing for housing the impeller rotatably. A size of a gap between a tip of the blade and an inner surface of the casing during a stop of the impeller is formed non-uniformly over a circumferential direction of the impeller.

Abstract: A turbocharger includes a turbine housing configured to house a turbine rotor provided on one side of a rotor shaft; and a bearing housing configured to house a bearing that rotatably supports the rotor shaft, in which at least one cooling water flow path through which cooling water flows is formed in at least one of the turbine housing and the bearing housing, and the at least one cooling water flow path is formed such that a plurality of flow path cross sections are present in, of a cross-section including an axis of the rotor shaft, a half cross-section divided by the axis.

Abstract: A rotor includes: a hub; and a plurality of blades disposed on the hub. Each of the plurality of blades includes a suction surface, a pressure surface, a leading edge, a trailing edge, a tip-side edge, and a hub-side edge. In a cross-section of each blade at a given chord position between the leading edge and the trailing edge, an angle of at least one of the suction surface or the pressure surface with respect to a blade height direction of the blade increases in a direction from the hub-side edge to the tip-side edge over a region from the hub-side edge to the tip-side edge, in at least a range from the leading edge to a chord position away from the leading edge toward the trailing edge.

Abstract: A centrifugal compressor includes an impeller, a compressor inlet pipe for guiding air to the impeller, a scroll passage disposed on an outer peripheral side of the impeller, and a bypass passage connecting the compressor inlet pipe and the scroll passage and bypassing the impeller. In a cross-section perpendicular to an axis of the compressor inlet pipe, when A1 is a connection portion on a downstream side in a rotational direction of the impeller of connection portions between an inner wall surface of the compressor inlet pipe and an inner wall surface of the bypass passage, C is a virtual circle constituting the inner wall surface of the compressor inlet pipe, and L1 is a tangent line of the virtual circle C at the connection portion A1, the inner wall surface of the bypass passage is formed from the connection portion A1 along the tangent line L1.

Abstract: A centrifugal compressor includes: an impeller; a compressor inlet tube configured to guide air to the impeller; a scroll flow passage disposed on a radially outer side of the impeller; a bypass flow passage branching from the scroll flow passage via a branch port, the bypass flow passage connecting to the compressor inlet tube not via the impeller; and a bypass valve capable of opening and closing a valve port disposed in the bypass flow passage. The branch port has a non-circular shape when viewed along a normal N1 of the branch port passing through a center of the branch port.

Abstract: A centrifugal compressor includes: a housing; an impeller rotatably disposed within the housing; a rotational shaft connected to the impeller; and a bearing member supporting the rotational shaft in the housing. An oil flow passage through which oil flows is formed in the housing. The oil flow passage includes a lubricating oil passage through which the oil flows as lubricating oil to be supplied to the bearing member, and a cooling oil passage through which the oil flows as cooling oil for heat exchange with a fluid compressed by the impeller. The cooling oil passage is configured so that the oil flows into the cooling oil passage as the cooling oil without passing through the bearing member.