Patent ID: 8851832

Claim:
A vane actuation system for a turbine engine, comprising: a unison ring for a vane stage of the turbine engine; a plurality of first links, each first link being coupled to a vane of the vane stage, and each first link being pivotably coupled to said unison ring; an other unison ring for an other vane stage of the turbine engine, wherein said unison ring and said other unison ring are not both disposed between said vane stage and said other vane stage; a plurality of second links, each second link being coupled to an other vane of the second vane stage, and each second link being pivotably coupled to said other unison ring; a third link having first and second ends, wherein the first and second ends of the third link are pivotably coupled to the unison ring and the other unison ring, respectively; and a fourth link pivotably coupled to said vane and said other vane, wherein the first, second, third and fourth links are configured to form a four-bar linkage; and wherein the four-bar linkage is configured to transmit rotation imparted to the unison ring from the unison ring to the other unison ring and/or to transmit rotation imparted to the other unison ring from the other unison ring to the unison ring.