Bearing systems for motor-assisted turbochargers for internal combustion

Abstract

In a unique turbocharger shaft bearing system, a thrust bearing is provided inboard of the compressor end shaft bearing. Removable parts of the turbocharger housing permit assembly of a first thrust bearing part with an outwardly extending flange forming at least one thrust bearing interface to be fastened to the rotating shaft for rotation therewith and a separate stationary thrust bearing part to be carried by the housing, providing thrust bearing interface for the thrust bearing interface of the rotating first thrust bearing part inboard of the compressor end of shaft bearing. The removable parts can include a separate supporting member for the compressor end shaft bearing. The remainder of the turbocharger housing supports the second shaft bearing adjacent its turbine end and, through the separate bearing supporting member, the first shaft bearing. The thrust bearing can also include a second rotating thrust bearing part carried by and rotating with the rotating shaft and providing an outwardly extending flange adjacent its turbine end spaced from the outwardly extending flange of the first rotating thrust bearing part and forming a second thrust bearing interface so the thrust bearing interface of the first rotating thrust bearing part can engage the separate stationary thrust bearing member on its compressor side while the thrust bearing interface of the second rotating thrust bearing part engages the thrust bearing member on its turbine side. Providing a thrust bearing inward of the compressor end shaft bearing minimizes bearing overhang, allows an increase in distance between the two shaft bearings, and improves bearing systems stability.