A bearing housing (1) of an exhaust-gas turbocharger 2, having an oil guide to at least one bearing point (5) in the bearing housing (1). The oil guide is formed by at least one of bores and cutouts in the bearing housing (1). There is formed in the oil guide a siphon (10) which is integrated into the bearing housing (1).

A bearing housing (1) of an exhaust-gas turbocharger 2, having an oil guide to at least one bearing point (5) in the bearing housing (1). The oil guide is formed by at least one of bores and cutouts in the bearing housing (1). There is formed in the oil guide a siphon (10) which is integrated into the bearing housing (1).

Disclosed is an intake joint structure capable of blocking backflow of lubricating oil 18 at a connection position between an air inlet 12 of a turbocharger and a suction pipe 24. A backflow-preventive plate 25 is integrally molded to have a cylindrical portion 25a fitted over the air inlet 12 and a tapered portion 25b curved inward from an upstream end of the cylindrical portion 25a and converged downstream to provide an open end. A downstream end 24a of a suction pipe 24 is molded by soft material over a predetermined range using exchange blow molding. The cylindrical portion 25a of the backflow-preventive plate 25 is fitted over the air inlet 12 through a grommet 26 (first soft layer) and the downstream end 24a of the suction pipe 24 is fitted over the cylindrical portion 25a and is banded by a hose band 27.

A multi-stage turbocharging assembly is described. The multi-stage turbocharging assembly includes a high-pressure stage including a high-pressure turbine coupled with a high-pressure compressor. Additionally, the multi-stage turbocharging assembly includes a low-pressure stage including a low-pressure turbine coupled with a low-pressure compressor: Further, the multi-stage turbocharging assembly includes a casing enclosing the high-pressure stage and the low-pressure stage, wherein the casing is a single unit.

A compressor housing for a turbocharger including a housing body having an inner circumferential recess recessively formed on an annular inner circumference surface thereof; an annular abradable seal disposed in the inner circumferential recess, an inner circumference surface of which forms a shroud surface; and a ring member formed in a ring shape along the inner circumferential recess and press-fitted into the inner circumferential recess. The inner circumferential recess includes a recess press-contact surface that is formed along a press-fitting direction of the ring member, and press-contacts a radial-direction outside surface of the ring member; and a recess opposing surface that opposes a press-fitting direction forward surface of the ring member. The abradable seal includes a flange that projects outwardly in a radial direction of the abradable seal. The flange is held between the press-fitting direction forward surface and the recess opposing surface to fix the abradable seal.

A gas passage that is connected to an exhaust passage and a water passage that is connected to a water jacket are formed in a turbine housing. The water passage and the gas passage are arranged adjacent to each other in an exhaust gas-introducing side joint part of the turbine housing, and a mating face in which the water passage opens and a mating face in which the gas passage opens are formed not to connect smoothly to each other. The turbine housing is attached to the cylinder head with an O-ring that prevents leakage of coolant interposed between the mating face and the cylinder head, and a seal member that prevents leakage of exhaust gas interposed between the mating face and the cylinder head.

A turbocharger waste gate valve includes an elastically deformable sealing member formed by sheet metal, the sealing member being carried on one of the poppet valve member and the valve housing and being arranged to be under compression between the valve seat and the valve member end face when the poppet valve member is in the closed position so as to be elastically deformed into a compressed state, and to be released from said compression so as to return to an uncompressed state when the poppet valve member is in the open position. The sealing member in the compressed state contacts the valve seat about a full circumference thereof and contacts the valve member end face about a full circumference thereof so as to substantially seal any gap between the valve member end face and the valve seat.

An apparatus, system, and method are disclosed for optimizing a valve orifice shape. According to one representative embodiment, a method includes determining a specified relationship between a valve position and an output characteristic, and determining an orifice profile. The method also includes determining a relationship of an orifice area to the output characteristic. Further, the method includes shaping an orifice in a valve based on the orifice profile and the specified relationship between the valve position and the output characteristic. According to the method, the valve should approximately exhibit the specified relationship.

An apparatus, system, and method are disclosed for optimizing a valve orifice shape. According to one representative embodiment, a method includes determining a specified relationship between a valve position and an output characteristic, and determining an orifice profile. The method also includes determining a relationship of an orifice area to the output characteristic. Further, the method includes shaping an orifice in a valve based on the orifice profile and the specified relationship between the valve position and the output characteristic. According to the method, the valve should approximately exhibit the specified relationship.

A turbocharger includes a turbine housing, a compressor housing, and a bearing housing. Each of the housings includes a passage for cooling inside. The turbocharger further includes a switching valve and a controller that switches a valve position of the switching valve. The switching valve is adapted to switch the circulation state of coolant in each passage such that the coolant is supplied from the passage of the turbine housing to the passage of the bearing housing or such that the coolant is supplied from another passage to the passage of the bearing housing. The controller switches the valve position of the switching valve such that the coolant is supplied from the passage of the turbine housing to the passage of the bearing housing until a predetermined amount of time passes after starting of the engine.