Patent attributes
A centrifugal compressor for a turbocharger includes an inlet-adjustment mechanism in an air inlet for the compressor, operable to move between an open position and a closed position in the air inlet. The inlet-adjustment mechanism includes a plurality of first blades disposed about the air inlet and each pivotable about one end of the blade, and a plurality of second blades axially adjacent to the first blades and disposed about the air inlet and each pivotable about one end of the blade, the first and second blades extending through a slot in the air inlet wall when the blades are in the closed position so as to form an orifice of reduced diameter relative to a nominal diameter of the inlet. Movement of the inlet-adjustment mechanism from the open position to the closed position is effective to shift the compressor's surge line to lower flow rates.
