System for controlling variable pitch blades for a turbine engine
The invention relates to a system for controlling variable pitch blades for a turbine engine, comprising an annular row of variable pitch blades extending about an axis (A) and each comprising a blade connected at the radially outer end thereof to a pivot ( 20 ) that defines a substantially radial axis of rotation of the blade and which is connected by a lever ( 34 ) to control means ( 40 a , 40 b ) extending about said axis. The invention is characterized in that said control means include first links ( 40 a ) supported by said pivots and second links ( 40 b ) extending between said first links, said first and second links extending substantially along a same circumference of said axis and being connected to one another and to actuation means ( 56 ).
1. A control system for variable-pitch vanes for a turbine engine, comprising at least one annular row of variable-pitch vanes extending around an axis and each comprising a blade which is connected at the radially outer end thereof to a pivot which defines a substantially radial axis of rotation of the vane and which is connected by a lever to control means extending around said axis, wherein said control means comprise first links carried by said pivots and second links extending between said first links, said first and second links extending substantially over the same circumference around said axis and being connected to one another and to actuation means.
2. The control system according to claim 1 , wherein the number of the first links is equal to the number of the second links, which is equal to the number of levers.
3. The control system according to claim 1 , wherein said first links are formed in one piece with said levers.
4. The control system according to claim 1 , wherein each of the first and/or second links has an elongate shape and is connected by the longitudinal ends thereof to other links.
5. The control system according to claim 1 , wherein the first links are connected by pivot and/or swivel connections to the second links.
6. The control system according to claim 1 , wherein the second links each have a general curved shape.
7. The control system according to claim 1 , wherein the first links ( 40 a ) are female links, and the second links are male links.
8. System according to claim 1 , wherein each lever has a general elongate shape and comprises a first longitudinal end for connection to the pivot of a vane and a second longitudinal end carrying one of said first links.
9. The control system according to claim 8 , wherein at least one of the levers comprises a longitudinal extension for connection to said actuation means.
10. The control system according to claim 1 , wherein said actuation means are connected to two annular rows of variable-pitch vanes.
11. The control system according to claim 6 , wherein said general curved shape extends in a plane which is substantially tangent to a circumference which is centred on said axis.