摘要 |
A turbocharger includes a compressor housing, a bearing housing and a back plate. A discharge scroll chamber has such a shape that a cross-sectional area thereof gradually increases toward a discharge port in a circumferential direction. The compressor housing includes a scroll piece assembled to a shroud piece. The scroll piece includes a suction port-forming portion, a suction-side concave surface and a scroll outer periphery. The shroud piece includes a shroud fit-in portion, an inner peripheral concave surface, a shroud surface and a diffuser surface. The back plate includes a facing surface, an outer peripheral annular fit-in portion and an outer peripheral concave surface. The outer peripheral concave surface has such a shape that a cross sectional shape thereof formed by a plane including a rotation axis of an impeller gradually changes in the circumferential direction. |