Patent ID: 7322791

Claim:
A turbine unit for a turbocharger comprising: a rotor housing ( 2 ) with at least one admission channel ( 9 ) for a fluid; a turbine rotor ( 4 ) which is supported in a rotor space ( 23 ) of the rotor housing ( 2 ); a nozzle ring ( 6 ) with a plurality of shafts ( 8 ) located on said nozzle ring ( 6 ) in a crown formation, and which comprises on one side vanes ( 7 ), which are susceptible to being turned from a substantially tangential position into a substantially radial position with respect to said crown, and at least one control lever ( 19 ) in order to change the position of the vanes ( 7 ); an actuation device ( 11 ) in order to create control movements which are transmitted to a VTG mechanism ( 5 - 8 ) with variable geometry; whereby transmission of the control movements is effectuated by a control ring ( 5 ) positioned coaxially with said nozzle ring ( 6 ) and adjacent thereto, and which is movably connected with said at least one control lever ( 19 ), as well as a guiding and centering device for the control ring ( 5 ), which comprises at least one roller ( 3 , 20 , 21 ) which substantially rolls on a roller contact surface ( 20 ) of the control ring ( 5 ); wherein said rollers ( 3 , 20 , 21 ) are arranged between the control ring ( 5 ) and a releasably connectable ring ( 6 , 38 ), wherein said releasably connectable ring is releasably connected with the rotor housing ( 2 ), and wherein said rollers ( 3 ), said control ring ( 5 ), said nozzle ring ( 6 ), said vanes ( 7 ), and a vane orientation mechanism ( 8 , 19 ) are assembled as a modular unit ( 26 ) being inserted into said housing ( 2 ) as one piece.