Patent ID: 7406826

Claim:
A variable-throat exhaust turbocharger equipped with a variable throat mechanism comprising a plurality of nozzle vanes supported rotatably by a nozzle mount fixed to a turbine casing, an annular drive ring connected to and rotated by an actuator, and lever plates identical in number with the number of the nozzle vanes, each of the lever plates being connected at one end to the drive ring via a connection pin and a groove into which the connection pin is engaged and at the other end to the nozzle vanes, whereby the lever plates are swung by rotating the drive ring and the nozzle vanes are rotated by the swing of the lever plates to vary the blade angle of the nozzle vanes, wherein said drive ring is disposed between said lever plates and nozzle mount side by side with the lever plates and nozzle mount in an axial direction thereof, and a plurality of partial circumferential grooves are provided at the outer side part of the nozzle mount, thereby receiving the drive ring in the partial circumferential grooves and preventing the drive ring from moving in the axial direction.