TURBINE CASE FOR TURBINE SUPERCHARGER

摘要

PURPOSE:To prevent the deterioration of turbine property owing to a thermal deformation, by forming the surface of a turbine case opposing to the impeller into a similar oval composed of an arc around the turbine axis and an arc eccentric to the turbine axis. CONSTITUTION:The inner periphery 4a of the upper half of a turbine case 1 is composed in an arc with the turbine axis O-O as the center. The inner periphery 4b of the lower half is composed in an eccentric arc with the center lower than the turbine axis O-O. The upper half 4a and the lower half 4b are connected in a smooth surface. Sections of a scroll member 5a and 5b are heated unevenly and expanded also unevenly by a high temperature exhaust gas passing through the scroll member. Therefore, the chip clearance C2 is set larger than the chip clearance C1.