Abstract: In a radial turbine scroll, an operating gas is led to flow in the radial direction from a spiral scroll formed in a turbine casing into turbine moving blades of a turbine rotor, which is positioned on the inner side of the scroll, so as to act on the turbine moving blades, and then led to flow outside in an axial direction, thereby rotatively driving the turbine rotor, wherein the scroll 4 has a partition plate 20 a length of a certain range on a line of a tongue portion formed on the inner periphery of a gas inlet portion or has a reduced height between scroll side walls at an outlet portion of a tongue portion 21 formed on the inner periphery of a gas inlet portion of the scroll.

Abstract: A variable geometry turbine includes a fluid space formed by a nozzle mount and a nozzle plate; and a plurality of nozzle vanes arranged in the fluid space at certain intervals in the circumferential direction so as to partition the fluid space. The nozzle vanes are supported by shafts on the nozzle mount, in such a manner as to be capable of turning. The flow rate of the discharged fluid can be adjusted by opening or closing the cross-sectional area of a flow path formed by the adjacent nozzle vanes. The nozzle plate is provided with plate projections protruding toward the nozzle vanes further than, at least, end surfaces of the nozzle vanes, so as to cover the spaces between leading edges of the nozzle vanes and trailing edges of the nozzle vanes adjacent thereto, when the nozzle vanes are at a closed position.

Abstract: In a scroll structure of a centrifugal compressor, there are provided a radius increase arc portion E in which a radius from the center of a scroll 12 to a scroll centroid P of the cross section of the scroll 12 is gradually increased in any range in a circumferential direction from the start of winding of the scroll, and a radius decrease arc portion F in which the radius is gradually decreased toward a scroll end point Z.

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: Bolt holes 16 are formed in a joint part 14 of a turbine housing 12, with flanged bolts 40 screwed in the bolt holes 16. A flange part 32 of a bearing housing 30 is sandwiched between bearing surfaces 44a of the flanged bolts 40 and an inner end face 14b of the joint part 14. A sealing ring 48 is interposed in an annular space s. Before the flanged bolts 40 are fastened, there is formed a height difference G equivalent to a compression allowance h for the sealing ring 48, between an outer end face 60a of the joint part 14 and a bolt receiving surface 32a of the flange part 32. The flanged bolts 40 are screwed into the bolt holes 16 until the bearing surfaces 44a make tight contact with the outer end face 60a so as to resiliently deform the sealing ring 48.

Abstract: The turbine housing 1 is formed by sheet metal scroll members 5 and 7 butted opposite each other and welded together. A center core part 9 arranged in a central part of the scroll part 3 is integrally formed in one piece from a steel pipe member such as to include a housing portion 93 surrounding a turbine wheel 24, a bearing receiving portion 91 axially supporting the turbine wheel 24, and a plurality of circumferentially spaced supports 92 bridging a gap between the housing portion 93 and the bearing receiving portion 91.

Abstract: In a turbine housing 12 of a turbocharger 10A of a twin-scroll type, a scroll-shaped passage is separated into a front scroll passage 42 and a rear scroll passage 44 by a partition wall 40. A front wall 50 and a root part 40b of the partition wall 40 curve toward a front side to secure cross-sectional areas a1, a2, a3 . . . and b1, b2, b3 . . . . The scroll passages 42, 44 are formed to have equal cross-sectional areas, a tip part 40a of the partition wall 40 is arranged perpendicular to the turbine rotor blade 26 and the scroll passages 42, 44 are symmetrical near the tip part 40a about an axis X so as to eliminate the flow rate difference.

Abstract: A turbine wheel includes a plurality of blades having a scallop cut-out profile. The scallop cut-out profile is formed by cutting-out a back side wall part of the blade between the suction surface side of a blade part and the pressure surface side of the adjacent blade.

Abstract: A sheet-metal turbine housing has a scroll part formed by joining opposing scroll members of sheet metal to form a spiral-shaped exhaust gas passage. The housing includes a member on a side of a bearing housing inclosing a bearing supporting a rotation shaft of a turbine rotor blade member on the exhaust side forms an outer side of the turbine rotor blade. Support columns connect the member on the side of the bearing housing with the member on the exhaust side in an axial direction of the turbine and are arranged at intervals on an outer circumference of the turbine. Each support columns may have a cross-sectional shape which includes an upstream corner and a downstream corner in a direction of a gas flow, each of which has an acute angle, so that an upstream surface and a downstream surface are inclined to the gas flow.

Abstract: In the neighborhood area X of the tongue part 27 forming the winding end part of the scroll part 3, the wall part members 31 are provided on both the sides of the welding part (the facing part) ‘a’ of the first scroll part 5 and the second scroll part 7, wherein: the wall part members 31 encloses the welding part (the facing part) ‘a’ and forms the gas-tight space 33; and, the outer circumference wall which enclose the facing part and forms a gas-tight space configure a double-wall structure.

Abstract: A turbine reduces variations in mass flow at throats even when the flow rate of fluid is low or high. The turbine includes a turbine rotor having turbine blades; a turbine housing accommodating the turbine rotor 80 and whose cross-sectional area of a scroll portion formed between the turbine housing and the turbine rotor gradually decreases; a plurality of fixed vanes fixed along a curved line dividing the scroll portion into an inner scroll part and an outer scroll part; throats formed between the adjacent fixed vanes and communicate between the inner scroll part and the outer scroll part; and a switch valve which switches a flow path in the turbine housing either to the inner scroll part or to both the inner scroll part and the outer scroll part, in which flow path areas of the throats are reduced in a downstream direction of the scroll portion.

Abstract: Providing a turbine rotor in which the rotational inertia of the turbine rotor can be reduced without changing the geometry of the blade part, whereas the turbine rotor is provided with the rear side surface so that the stress concentration appearing at the root part regarding the hub part on the rear surface side is constrained in order that the strength and the durability of the turbine rotor can be enhanced.

Abstract: A mixed flow turbine or radial turbine suppresses a rapid increase in load applied on a leading edge of a blade, and can reduce incidence loss. The mixed flow turbine or radial turbine includes a hub, and a plurality of blades provided on an outer circumference surface of the hub at substantially equal intervals. The camber line of the blade section is convex-curved to the rotational direction side as seen entirely from a leading edge side toward trailing edge side. On a leading edge section of the blade, there is provided an inflected section that is inflected so that a camber line in a sectional surface along the outer circumference surface is concave-curved to the rotational direction side.

Abstract: A two-stage turbo system using small-sized turbo-superchargers and simply configured. A two-stage turbo system provided with an internal combustion engine (1), two turbo-superchargers (2A, 2B) driven by exhaust gas from the internal combustion engine (1), control valves (V1-V5) for switching between the flow path of intake gas sucked into the internal combustion engine (1) and the flow path of exhaust gas from the internal combustion engine (1), and a control device for controlling the control valves (V1-V5) and the turbo-superchargers (2A, 2B).

Abstract: A variable capacity exhaust gas turbocharger having a small thermal capacity and enabling the structure to be simplified. A exhaust gas inlet hardware (13) having an exhaust gas inlet body (11) in which an inner side flow passage (U1) communicating with an inner scroll passage (T1) and an outer side flow passage (U2) communicating with an outer scroll flow passage (T2) are formed and a flap valve (12) for opening and closing the outer side flow passage (U2) are formed at the exhaust gas inlet part of a turbine housing body (14) in which the inner scroll passage (T1) and the outer scroll flow passage (T2) are formed. A valve recess (11a) for disposing the flap valve (12) along the outer side flow passage (U2) and a seat (11b) for the flap valve for closing the outer side flow passage (U2) are formed in the exhaust gas inlet body (11).

Abstract: Provided is a manufacturing method for a variable capacity exhaust gas turbine whereby, with variable capacity exhaust gas turbine component members produced using casting or other element molding and with which the final finished product is obtained using machining, the gap in a tongue section to allow an exhaust gas stream to flow smoothly into an inner circumferential scroll section can be formed at a minimum, and mounting of a cover section near a ring can be accomplished with high precision.

Abstract: A structure of a radial turbine scroll avoids a gas flow heading from a radially outer side toward a radially inner side in the vicinity of a tongue portion so as to restrain turbine performance from deteriorating and also reduces, to a maximum, thermal stress caused by the formation of the tongue portion.

Abstract: An exhaust turbo-supercharger having a high efficiency is provided. The exhaust turbo-supercharger includes therein an exhaust turbine housing including a spiral channel and a turbine-accommodating chamber connected to an innermost peripheral part of the spiral channel; an exhaust turbine provided in the turbine-accommodating chamber so that the axial line of the exhaust turbine is parallel to that of the spiral channel; a shaft that is concentrically connected to one side of the exhaust turbine in the axial line direction; a bearing housing disposed at the side of the exhaust turbine in the axial line direction so as to be adjacent to the exhaust turbine housing; a bearing that is provided in the bearing housing and that rotatably supports the shaft around the axial line; and a heat shield component interposed between the exhaust turbine housing and the bearing housing.

Abstract: A turbine is provided which can reduce variations in mass flow at throats even when the flow rate of fluid is low or high, to prevent a decrease in performance. The invention employs a turbine including a turbine rotor which has turbine blades; a turbine housing which accommodates the turbine rotor 80 and whose cross-sectional area of a scroll portion formed between the turbine housing and the turbine rotor gradually decreases; a plurality of fixed vanes which are fixed along a curved line dividing the scroll portion into an inner scroll part and an outer scroll part; throats which are formed between the adjacent fixed vanes and communicate between the inner scroll part and the outer scroll part; and a switch valve which switches a flow path in the turbine housing either to the inner scroll part or to both the inner scroll part and the outer scroll part, in which flow path areas of the throats are reduced in a downstream direction of the scroll portion.

Abstract: An exhaust turbocharger with a variable-nozzle mechanism with fail-safe feature included is provided with which, even if wear of the drive ring supporting part where the supporting elements are in reciprocating sliding or rolling contact with each other under high temperature without lubrication increases, the drive ring can be supported on the nozzle mount on the second supporting part, which enables the drive ring to be always supported rightly on the nozzle mount, and to prevent the occurrence of eccentric rotation or dropping out of the drive ring due to excessive wear of the drive ring supporting part or the occurrence of reduction in engine performance due to malfunctions of the variable-nozzle mechanism such as the error in the relation between the output of the actuator and the nozzle vane opening or the occurrence of breakage of the variable-nozzle mechanism as has been experienced in prior arts.