Variable Camber Trim Unit Selective Coupling Decoupled Gears

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional variable camber trim units in aircraft are large, heavy, and complex, leading to differential rotation between input and output shafts due to clutch slippage, which complicates the independent actuation of inboard and outboard flaps.

Innovation Solution

A variable camber trim unit with a housing supporting input and output gears, configurable in coupled and decoupled modes, allowing selective coupling and decoupling of rotational movement, enabling independent control of inboard and outboard flight-control surfaces.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If conventional clutch systems with friction disks are used to connect inboard and outboard shafts, then the system can provide coupled and decoupled configurations, but the system becomes large, heavy, and complex with differential rotation due to clutch slippage

Engineering Contradiction:

Improvecoupled and decoupled configurationsVSAvoidsystem complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent removes the complex clutch assembly (friction disks, springs, actuators) from the system entirely. Instead of using a clutch to engage and disengage the connection between inboard and outboard shafts, the invention uses a direct mechanical linkage through bevel gears that can be selectively positioned to either transmit or block rotational motion, eliminating the need for friction-based coupling mechanisms.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent replaces the friction-based clutch mechanism with a positive mechanical engagement system using bevel gears and a positioning mechanism. This substitution eliminates slippage and differential rotation issues inherent in friction-based systems, providing more reliable and precise coupling and decoupling of the shafts.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Adaptability or versatility

If conventional clutch systems are used, then coupled and decoupled configurations are achieved, but weight increases due to friction disks and spring stacks

Engineering Contradiction:

Improvecoupled and decoupled configurationsVSAvoidtrim unit weight

Core Design Contradiction:

Adaptability or versatilityVSWeight of moving object

Solution Approach 1:

The patent removes the heavy components of conventional clutch systems, specifically the friction disks and spring stacks, from the trim unit. The replacement mechanism uses lighter bevel gears and a simplified positioning system that achieves the same coupled and decoupled functionality with significantly reduced weight.

Inventive Principle:

Principle #2Taking out (Extraction)

3Adaptability or versatility

If clutch slippage occurs in conventional systems, then decoupling is achieved, but differential rotation between input and output shafts is caused

Engineering Contradiction:

Improvedecoupled configurationVSAvoidrotational synchronization

Core Design Contradiction:

Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

4Adaptability or versatility

If conventional clutch mechanisms are used, then selective coupling is possible, but the overall system size increases

Engineering Contradiction:

Improveselective coupling capabilityVSAvoidtrim unit volume

Core Design Contradiction:

Adaptability or versatilityVSVolume of moving object

Solution Approach 1:

The patent removes the bulky components of conventional clutch systems, specifically the friction disks and spring stacks, from the trim unit. The replacement mechanism uses lighter bevel gears and a simplified positioning system that achieves the same coupled and decoupled functionality with significantly reduced weight.

Inventive Principle:

Principle #2Taking out (Extraction)

Data Source

PatentUS11370528B2Variable camber trim units, aircraft comprising the same, and associated methods of operation

Publication Date: 2022.06.28 THE BOEING CO

AI summary

A variable camber trim unit comprises a housing, an input gear, and an output gear. The input gear and the output gear are rotatably supported by the housing. The variable camber trim unit is selectively configurable to one of a coupled configuration or a decoupled configuration. When the variable camber trim unit is in the coupled configuration, rotation of the input gear relative to the housing causes rotation of the output gear relative to the housing. When the variable camber trim unit is in the decoupled configuration, rotation of the input gear relative to the housing does not cause rotation of the output gear relative to the housing, and the output gear is capable of at least 5° and no more than 15° of rotation relative to the housing.