Abstract: A supercharger includes a housing, and a turbine shaft supported in a center hole in the housing through rolling bearings. Lubricating oil for the rolling bearings exists only within the housing. A cooling water jacket is provided within a body portion of the housing over a region from one axial end portion of the body portion to the other axial end portion thereof.

Abstract: A supercharger includes a housing, and a turbine shaft supported in a center hole in the housing through rolling bearings. Lubricating oil for the rolling bearings exists only within the housing. A cooling water jacket is provided within a body portion of the housing over a region from one axial end portion of the body portion to the other axial end portion thereof.

Abstract: There are provided an inner ring having a first raceway at an outer periphery thereof, an outer ring having a second raceway at an inner periphery thereof, an intermediate ring which is interposed between these, and has a third raceway at an inner periphery thereof and also has a fourth raceway at an outer periphery thereof, first rolling elements interposed between the first raceway and the third raceway, and second rolling elements interposed between the fourth raceway and the second raceway. The intermediate ring includes a larger-diameter ring portion, and a smaller-diameter ring portion formed on the larger-diameter ring portion through an inclined ring portion. The third raceway is formed at a boundary portion between the larger-diameter ring portion and the inclined ring portion, and the fourth raceway is formed at a boundary portion between the smaller-diameter ring portion and the inclined ring portion.