Systems and Methods to Control Variable Stator Vanes in Gas Turbine Engines

Abstract

Embodiments of the present application include a variable stator vanes control mechanism for a gas turbine engine. The control mechanism may include a moveable actuation rod in operative communication with a gear ring such that movement of the actuation rod drives the gear ring. The control mechanism may also include a first plurality of variable stator vanes disposed on a first side of the gear ring, the first plurality of variable stator vanes comprising gear stems in operative communication with the gear ring. Moreover, the control mechanism may include a second plurality of variable stator vanes disposed on a second side of the gear ring, the second plurality of variable stator vanes comprising gear stems in operative communication with the gear ring.

That which is claimed: 
     
         1 . A variable stator vanes control mechanism for a gas turbine engine, comprising:
 a gear ring;   a moveable actuation rod in operative communication with the gear ring such that movement of the actuation rod drives the gear ring;   a first plurality of variable stator vanes disposed on a first side of the gear ring, the first plurality of variable stator vanes comprising a first plurality of respective gear stems in operative communication with the gear ring; and   a second plurality of variable stator vanes disposed on a second side of the gear ring, the second plurality of variable stator vanes comprising a second plurality of respective gear stems in operative communication with the gear ring.   
     
     
         2 . The control mechanism of  claim 1 , wherein the first plurality of variable stator vanes is in operative communication with the gear ring by way of a gear train. 
     
     
         3 . The control mechanism of  claim 1 , wherein the second plurality of variable stator vanes is in operative communication with the gear ring by way of a gear train. 
     
     
         4 . The control mechanism of  claim 1 , wherein the first plurality of variable stator vanes and the second plurality of variable stator vanes are in operative communication with the gear ring such that they rotate in similar directions. 
     
     
         5 . The control mechanism of  claim 1 , wherein the first plurality of variable stator vanes and the second plurality of variable stator vanes are in operative communication with the gear ring such that they rotate in opposite directions. 
     
     
         6 . The control mechanism of  claim 1 , wherein the gear ring is disposed about a rub block. 
     
     
         7 . The control mechanism of  claim 1 , wherein the gear ratio is adjusted to control the schedule between variable stator vane stages. 
     
     
         8 . The control mechanism of  claim 1 , wherein the number of teeth on the gears is adjusted to control the schedule between variable stator vane stages 
     
     
         9 . The control mechanism of  claim 1 , wherein the moveable actuator rod is at least partially secured to a casing of a compressor. 
     
     
         10 . The control mechanism of  claim 1 , wherein the movable actuator drives at least two variable stator vane stages. 
     
     
         11 . A method to control variable stator vanes in a gas turbine engine, comprising:
 actuating a moveable actuation rod in operative communication with a gear ring such that movement of the actuation rod drives the gear ring;   driving a first plurality of variable stator vanes disposed on a first side of the gear ring, the first plurality of variable stator vanes comprising a first plurality of respective gear stems in operative communication with the gear ring; and   driving a second plurality of variable stator vanes disposed on a second side of the gear ring, the second plurality of variable stator vanes comprising a second plurality of respective gear stems in operative communication with the gear ring.   
     
     
         12 . The method of  claim 11 , further comprising:
 rotating the first plurality of variable stator vanes and the second plurality of variable stator vanes are in similar directions.   
     
     
         13 . The method of  claim 11 , further comprising:
 rotating the first plurality of variable stator vanes and the second plurality of variable stator vanes are in opposite directions.   
     
     
         14 . The method of  claim 11 , further comprising:
 adjusting the gear ratio and the number of gear teeth to control the schedule between variable stator vane stages.   
     
     
         15 . A variable stator vanes control mechanism for a gas turbine engine, comprising:
 a compressor having a compressor casing;   a gear ring disposed about the compressor casing;   a moveable actuation rod in operative communication with the gear ring such that movement of the actuation rod drives the gear ring about the compressor casing;   a first plurality of variable stator vanes disposed on a first side of the gear ring, the first plurality of variable stator vanes comprising a first plurality of respective gear stems in operative communication with the gear ring by way of a plurality of respective connecting gears; and   a second plurality of variable stator vanes disposed on a second side of the gear ring, the second plurality of variable stator vanes comprising a second plurality of respective gear stems in operative communication with the gear ring;   wherein the first plurality of variable stator vanes and the second plurality of variable stator vanes are in operative communication with the gear ring such that they rotate in similar directions.   
     
     
         16 . The control mechanism of  claim 15 , wherein the gear ring is disposed about a rub block. 
     
     
         17 . The control mechanism of  claim 15 , wherein the gear ratio is adjusted to control the schedule between variable stator vane stages. 
     
     
         18 . The control mechanism of  claim 15 , wherein the moveable actuator rod is at least partially secured to a casing of a compressor. 
     
     
         19 . The control mechanism of  claim 15 , wherein the movable actuator rod drives at least two variable stator vane stages. 
     
     
         20 . The control mechanism of  claim 15 , wherein the number of teeth on the gears is adjusted to control the schedule between variable stator vane stages