Patent attributes
A turbocharger assembly including a housing, a shaft, and turbine and compressor wheels mounted on opposite ends of the shaft. The shaft is rotatably supported within the housing by a bearing cartridge that includes turbine-side and compressor side ball-bearing assemblies that are longitudinally spaced by a spacer. There are two times as many rows of ball-bearings included in the turbine-side ball-bearing assembly compared to the compressor-side ball-bearing assembly. The spacer slides over and rotates with the shaft and has at least one flat. An optical sensor extends through the housing and an optical sensor opening in the bearing cartridge to prevent the bearing cartridge from rotating within the housing. The optical sensor detects rotational speed of the spacer by counting the number of times the flat(s) passes by the optical sensor during a pre-determined time interval.
