Turbocharger, notably for a combustion engine

Abstract

The turbocharger comprises a shaft 14, a housing 12, a turbine wheel 20 and a compressor wheel 22 mounted onto the shaft, and at least a rolling bearing 18 disposed between the shaft and the housing and comprising an inner ring 26, an outer ring 28 and at least one row of rolling elements 30 disposed into a rolling space 40 defined between the rings. A damping space 38 is defined between an outer surface 28a of the outer ring and a bore 16 of the housing inside which a lubricant is located.

Description

CROSS-REFERENCE[0001]This application claims priority to European Patent Application No. EP11305761.6 filed on Jun. 17, 2011.FIELD OF THE INVENTION[0002]The present invention relates to the field of turbochargers, and in particular those used in combustion engines for automotive vehicles.BACKGROUND OF THE INVENTION[0003]In such application, a turbocharger is used to enhance the combustion engine performance by blowing compressed air into the cylinders of said engine.[0004]A turbocharger generally comprises a housing, a shaft extending through an opening formed on the housing, a turbine wheel mounted on a first end portion of the shaft and located in an exhaust gases passage of the combustion engine, a compressor wheel mounted on an opposite second end portion of said shaft and located in an admission gases passage of the engine, and rolling bearings disposed between the shaft and the housing. When the turbine wheel is rotated by the flow of the exhaust gases, the shaft and the compr...

AI Technical Summary

Benefits of technology

The present invention provides a simple and economic turbocharger that has good sealing and damping properties. The turbocharger includes a shaft, housing, turbine wheel, and compressor wheel mounted onto the shaft, and at least one rolling bearing between the shaft and housing. The rolling bearing has inner and outer rings with rolling elements in a rolling space defined between the rings. The turbocharger also has at least two sealing means closing the rolling space and damping space, which may be offset outwards or radially between the shaft and housing. The sealing means may be axially or radially between the inner and outer rings. The axial length of the rolling bearing ranges between 30% and 95% of the axial dimension of the housing.

Problems solved by technology

However, when the combustion engine stops, the delivery of engine oil is shut off.

The cooling of said rolling bearing is thus not satisfactory.

Otherwise, the engine oil may contain foreign matter, for example small metal particles, thereby causing a premature wear of the rolling bearings.

This leads to a complex structure of the turbocharger as well as an increase of the mounting cost.

Images