Variable Vane Drive System With Dual Annular Rings

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current variable vane actuation systems in gas turbine engines face inefficiencies due to elastic deflection and assembly slop, which can lead to misalignment and increased wear, affecting thermal, transfer, and propulsive efficiencies.

Innovation Solution

A system comprising multiple annular rings and vane arms, with bell cranks and actuators, that move the rings to pivot the vanes, incorporating load relief slots to reduce resistive forces and maintain alignment, allowing independent actuation of variable vanes to optimize engine performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional sync-ring actuation systems are used, then variable vanes can be actuated, but elastic deflection and assembly slop cause misalignment and increased wear

Engineering Contradiction:
Improvealignment precisionVSAvoidelastic deflection and assembly slop
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The system divides the traditional single sync-ring into two separate annular rings (first annular ring and second annular ring) that can move independently. Each ring is actuated by its own bell crank mechanism, allowing precise control of vane angles without the elastic deflection and assembly slop problems of the traditional single-ring design. This segmentation enables better alignment precision and reduces wear.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces bell cranks as intermediary mechanisms between the actuators and the annular rings. These bell cranks translate actuator motion into precise rotational movement of the rings, providing a mediating function that eliminates direct elastic deflection and assembly slop while maintaining reliable vane actuation.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Productivity

If variable vanes are actuated to optimize engine performance, then thermal and propulsive efficiencies improve, but component wear increases

Engineering Contradiction:
Improveengine efficiencyVSAvoidcomponent wear
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

By segmenting the actuation system into independent annular rings with separate bell cranks, the patent reduces the mechanical stress and friction on individual components. This segmentation allows the vanes to be actuated for optimal engine performance while minimizing the wear that would otherwise occur in traditional synchronized systems.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The design incorporates load relief slots in the annular rings that act as beforehand cushioning mechanisms. These slots allow controlled movement and stress relief during the actuation process, preventing excessive wear on components while maintaining the ability to optimize engine performance through precise vane angle control.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

Data Source

PatentEP2971599B1Variable vane drive system
Publication Date: 2018.04.04 UNITED TECH CORP
  • EP2971599B1 patent drawingFigure 1
  • EP2971599B1 patent drawingFigure 2
  • EP2971599B1 patent drawingFigure 3a~6

AI summary

An example section of a gas turbine engine includes a plurality of variable vanes circumferentially disposed about an engine axis, a first moveable annular ring disposed on an upstream side of the variable vanes, a second movable annular ring disposed on a downstream side of the variable vanes, and a plurality of vane arms, each including a first end secured to the first annular ring and a second end secured to the second annular ring. Movement of the first and second annular rings moves the vane arms, thereby actuating the plurality of variable vanes. An example variable vane assembly includes a vane arm including a portion that engages a variable vane, a first end configured to be secured to a first movable annular ring, and a second end configured to be secured to a second movable annular ring. Movement of the first and second annular rings moves the vane arms, thereby actuating the plurality of variable vanes. An example method of actuating a variable vane assembly includes the steps of securing a variable vane to a vane arm, the vane arm secured to a first movable annular ring at a first end and a second movable annular ring at a second end, and moving at least one of the first and second rings to move the vane arm.