Composite Hinge Support for Rotor Blade Pitch Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional control systems for collective pitch of rotor blades in rotary-wing aircrafts are heavy, complex, and require extensive maintenance due to their mechanical design, which includes multiple components and metal parts prone to corrosion.

Innovation Solution

A control system utilizing a hinge support made of fiber-reinforced composite materials with a carrier element and base element, bonded together with countersunk head bolts and double barrel nuts, eliminating the need for spherical bearings and reducing the number of components, allowing for a lightweight and simpler design that can handle high loads.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Weight of moving object

If conventional spherical bearings and multiple metal components are used in the control system, then the structural integrity and load-bearing capacity are maintained, but the overall weight increases and maintenance requirements increase

Engineering Contradiction:
Improveweight of control systemVSAvoidstructural integrity
Core Design Contradiction:
Weight of moving objectVSReliability

Solution Approach 1:

The hinge support is constructed using fiber-reinforced composite materials (carbon fiber, glass fiber, aramid fiber) combined with metal inserts, creating a hybrid structure that maintains load-bearing capacity while significantly reducing weight compared to conventional all-metal spherical bearing designs

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The invention eliminates spherical bearings and other unnecessary intermediate components from the control system, directly connecting the swash plate assembly to the rotor shaft through a simplified hinge support structure, thereby reducing maintenance requirements and component count while preserving structural integrity

Inventive Principle:
Principle #2Taking out (Extraction)

2Device complexity

If conventional metal components and spherical bearings are used, then the load-bearing capacity is sufficient, but the device complexity and maintenance requirements increase

Engineering Contradiction:
Improvenumber of componentsVSAvoidload-bearing capacity
Core Design Contradiction:
Device complexityVSForce

Solution Approach 1:

Multiple functions are merged into the single hinge support structure: it provides pivoting motion, supports axial loads, and enables collective pitch control, eliminating the need for separate spherical bearings, pivot joints, and other intermediate components that would increase device complexity

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The hybrid composite structure with fiber reinforcement and metal inserts provides sufficient load-bearing capacity for high-force applications while reducing the number of separate metal components needed, thereby simplifying the overall device complexity

Inventive Principle:
Principle #40Composite materials

3Ease of repair

If conventional metal components are used throughout the control system, then the structural strength is adequate, but corrosion resistance and maintenance requirements worsen

Engineering Contradiction:
Improvemaintenance requirementsVSAvoidcorrosion resistance
Core Design Contradiction:
Ease of repairVSObject-affected harmful factors

Solution Approach 1:

Fiber-reinforced composite materials inherently resist corrosion from moisture, chemicals, and environmental factors, eliminating the corrosion issues associated with conventional metal components while reducing maintenance requirements for inspection and replacement

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

By removing spherical bearings and other metal-to-metal contact components, the invention eliminates the primary sources of corrosion and wear, significantly reducing maintenance requirements and improving ease of repair

Inventive Principle:
Principle #2Taking out (Extraction)

Data Source

PatentEP3281869B1A control system for controlling at least collective pitch of rotor blades of a multi-blade rotor in a rotary-wing aircraft
Publication Date: 2019.04.17 AIRBUS HELICOPTERS DEUT GMBH
  • EP3281869B1 patent drawingFigure 1
  • EP3281869B1 patent drawingFigure 2~3
  • EP3281869B1 patent drawingFigure 4

AI summary

The invention is related to a control system 10 for controlling at least collective pitch of rotor blades 1b, 1c of a multi-blade rotor 1a with a rotor shaft 1e in a rotary-wing aircraft 1, said control system 10 comprising a non-rotating sliding sleeve 13 that is mountable to the rotor shaft 1e such that the non-rotating sliding sleeve 13 is axially displaceable coaxially to an associated rotor axis 1f on the rotor shaft 1e, at least one actuator arm 20b that is pivotally mounted to the non-rotating sliding sleeve 13 and adapted for axially displacing the non-rotating sliding sleeve 13 that is mounted to the rotor shaft 1e upon activation, and at least one hinge support 21 that is adapted for a hinged support of the at least one actuator arm 20b.