Abstract: A method of manufacturing a multistage exhaust turbocharger having a high-pressure stage turbocharger and a low-pressure stage turbocharger includes providing a high-pressure turbine housing of the high-pressure stage turbocharger, the high-pressure turbine housing being integrally formed with the exhaust manifold by casting or welding, assembling constituent parts of the high-pressure stage turbocharger using the high-pressure turbine housing as a reference, after the assembling constituent parts of the high-pressure stage turbocharger, attaching the low-pressure stage turbocharger to the high-pressure stage turbocharger by attaching a low-pressure turbine housing to a low-pressure turbine connection flange, and after the attaching the low-pressure stage turbocharger, attaching an air supply channel to connect between a supply air outlet of the low-pressure stage turbocharger and a supply air inlet of the high-pressure stage turbocharger, wherein the low-pressure turbocharger is disposed below the high-press

Abstract: A multistage exhaust turbocharger is easily mountable in a narrow engine compartment of a vehicle by simplifying its construction and reducing its bulk. The multistage exhaust turbocharger has a high-pressure stage turbocharger and a low-pressure stage turbocharger. A cover of the high-pressure stage turbocharger has a compressor inlet passage, a bypass inlet passage, a switching aperture between the passages to be opened and closed by a valve body of the compressor bypass valve device, and a bypass outlet pipe part connecting to the bypass inlet passage to introduce bypass air passed through the aperture opened by the bypass valve to the compressor bypass channel which is to be connected to the bypass outlet pipe part.

Abstract: A method of manufacturing a multistage exhaust turbocharger having a high-pressure stage turbocharger and a low-pressure stage turbocharger reduced in pipe connection between the turbochargers thereby reducing the bulk of the multistage exhaust turbocharger, the number of parts for the connection, and assembling man-hours, and facilitating the mounting of an engine equipped with the multistage exhaust turbocharger in a narrow engine room of a vehicle. A high-pressure turbine housing is formed integral with an exhaust manifold of the engine, constituent parts of the high-pressure stage turbocharger is assembled to the high-pressure turbine housing formed integral with the manifold, the low-pressure stage turbocharger is connected to the high-pressure stage turbocharger by attaching a low-pressure turbine housing of the low-pressure stage turbocharger to a low-pressure turbine housing connection flange provided at an exhaust gas outlet side of the high-pressure stage turbocharger.

Abstract: An engine equipped with a multistage exhaust turbocharger easily mountable in a narrow engine room of a vehicle is provided by simplifying in construction and reducing in bulk of the multistage exhaust turbocharger. The multistage exhaust turbocharger has a high-pressure stage turbocharger and a low-pressure stage turbocharger. A high-pressure compressor cover of the high-pressure stage turbocharger is composed such that it has a compressor inlet passage, a bypass inlet passage, a switching aperture between both the passages to be opened and closed by a valve body of the compressor bypass valve device, and a bypass outlet pipe part connecting to the bypass inlet passage to introduce bypass air passed through the aperture opened by the bypass valve to the compressor bypass channel which is to be connected to the bypass outlet pipe part.