Turbocharger

Abstract

A turbocharger ( 1 ) with variable turbine geometry (VTG) having a guide grate ( 18 ) which surrounds a turbine wheel ( 4 ) radially at the outside, which has an adjusting ring ( 5 ) operatively connected to the guide blades ( 7 ) via associated blade levers ( 20 ) which are fastened to blade shafts ( 8 ) at one of the ends thereof. Each blade lever ( 20 ) has a lever head ( 23 ) which can be placed in engagement with an associated engagement recess ( 24 ), which has a base wall ( 26 ), of the adjusting ring ( 5 ), and which has a stop ( 25 ) at least for setting the minimum throughflow through the nozzle cross sections formed by the guide blades ( 7 ). The stop is a first support point ( 25 ) on the base wall ( 26 ), wherein, in the minimum throughflow position, the lever head ( 23 ) makes contact, via a wall surface ( 27 ) facing toward the base wall ( 26 ), with said first support point.

The invention claimed is: 
     
       1. A turbocharger ( 1 ) with variable turbine geometry (VTG) having
 a turbine housing ( 2 ) with a supply duct ( 9 ) for exhaust gases; 
 a turbine wheel ( 4 ) which is mounted rotatably in the turbine housing ( 2 ); and 
 a guide grate ( 18 )
 which surrounds the turbine wheel ( 4 ) radially at the outside, 
 which has a blade bearing ring ( 6 ), 
 which has a multiplicity of guide blades ( 7 ) which have in each case one blade shaft ( 8 ) mounted in the blade bearing ring ( 6 ), 
 which has an a rotatable adjusting ring ( 5 ) operatively connected to the guide blades ( 7 ) via associated blade levers ( 20 ) which are fastened to the blade shafts ( 8 ) at one of the ends thereof, wherein each blade lever ( 20 ) has, at the other end, a lever head ( 23 ) which can be placed in engagement with an associated engagement recess ( 24 ), in the adjusting ring (5), which engagement recess (24) has a base wall ( 26 ), of the adjusting ring ( 5 ), and 
 which has a minimum stop ( 25 ) at least for setting the minimum throughflow through the nozzle cross sections formed by the guide blades ( 7 ), 
 wherein the minimum stop is a minimum stop support point ( 25 ) on the base wall ( 26 ) of the engagement recess, wherein, in the minimum throughflow position, the lever head ( 23 ) makes contact, via a lever head wall surface ( 27 ) facing toward the base wall ( 26 ), with said minimum stop support point ( 25 ) so that the adjusting ring (5) is stopped from further rotating past the minimum stop by the contact between lever head wall surface (27) of the lever head (23) and the base wall (26) of the engagement recess of the adjusting ring (5). 
 
 
     
     
       2. The turbocharger as claimed in  claim 1  wherein a further stop in the form of a second support point ( 28 ) on the base wall ( 26 ) is provided, wherein in a maximum throughflow position, the lever head ( 23 ) makes contact, via the wall surface ( 27 ) facing toward the base wall ( 26 ), with said second support point. 
     
     
       3. The turbocharger as claimed in  claim 2 , wherein the first and second support points ( 25 ,  28 ) are arranged symmetrically with respect to a radius line (R) running through a central point (M 8 ) of the blade shaft ( 8 H) which is assigned to the lever head ( 23 ). 
     
     
       4. The turbocharger as claimed in  claim 1 , wherein, in an intermediate blade position (ST M ), there is play (S) between the base wall ( 26 ) and the wall surface ( 27 ), which points toward said base wall ( 26 ), of the lever head ( 23 ). 
     
     
       5. A turbocharger (1) with variable turbine geometry (VTG) having
 a turbine housing (2) with a supply duct (9) for exhaust gases;   a turbine wheel (4) which is mounted rotatably in the turbine housing (2); and   a guide grate (18)
 which surrounds the turbine wheel (4) radially at the outside, 
 which has a blade bearing ring (6), 
 which has a multiplicity of guide blades (7) which have in each case one blade shaft (8) mounted in the blade bearing ring (6), 
 which has a rotatable adjusting ring (5) operatively connected to the guide blades (7) via associated blade levers (20) which are fastened to the blade shafts (8) at one of the ends thereof, wherein each blade lever (20) has, at the other end, a lever head (23) in engagement with an associated engagement recess (24) in the adjusting ring (5), which engagement recess (24) has a base wall (26), of the adjusting ring (5), and 
 which has a maximum stop at least for setting the maximum throughflow through the nozzle cross sections formed by the guide blades (7), 
 wherein the maximum stop is a maximum stop support point (28) on the base wall (26) of the engagement recess, wherein, in the maximum throughflow position, the lever head (23) makes contact, via a lever head wall surface (27) facing toward the base wall (26), with said maximum stop support point (28) so that the adjusting ring (5) is stopped from further rotating past the maximum stop by the contact between lever head wall surface (27) of the lever head (23) and the base wall (26) of the engagement recess of the adjusting ring (5).