Aircraft Seat Lock Mechanism Wire Mounting and Maintenance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing lock mechanism for aircraft passenger seats experiences reduced movement of lock pins due to wire stretching, leading to malfunction and requiring frequent maintenance, including wire trimming and reconnection, which also compromises the rigidity of the wire mounting bracket.

Innovation Solution

A lock mechanism with a handle unit featuring a center hole and side wire mounting holes, where the wires pass through slits communicating with the center hole, allowing for easy maintenance and using lightweight materials like aluminum alloy to maintain rigidity and reduce weight.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If metal wires are used to connect the handle unit and lock pins, then the lock mechanism can be operated, but the wires stretch over time causing reduced lock pin movement and malfunction

Engineering Contradiction:
Improvelock mechanism operation reliabilityVSAvoidmetal wire length
Core Design Contradiction:
ReliabilityVSLength of moving object

Solution Approach 1:

The patent changes the material parameter from metal wire to nylon cord, which has different physical properties including resistance to stretching. This parameter change resolves the contradiction by maintaining operational reliability while preventing the length change that causes malfunction.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent uses a replaceable nylon cord that can be easily replaced when worn, accepting that the cord has a limited service life. This approach prioritizes reliability during the service period and simplifies maintenance compared to attempting to extend the life of metal wires.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

2Ease of repair

If the wire mounting bracket is made rigid to prevent wire stretching, then maintenance becomes difficult, but if it is made accessible for maintenance, then structural integrity may be compromised

Engineering Contradiction:
Improvewire maintenance accessibilityVSAvoidwire mounting bracket rigidity
Core Design Contradiction:
Ease of repairVSStrength

Solution Approach 1:

The patent segments the wire mounting bracket into a fixed portion attached to the seat frame and a movable portion that can be detached. This allows the bracket to maintain structural integrity when closed while enabling easy access for wire replacement during maintenance.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The wire mounting bracket incorporates a movable cover that can open and close, transforming the static rigid structure into a dynamic one that adapts between providing structural support and enabling maintenance access.

Inventive Principle:
Principle #15Dynamics

3Productivity

If traditional wire mounting structures are used, then the bracket requires frequent maintenance, but the overall seat weight remains high

Engineering Contradiction:
Improvemaintenance frequencyVSAvoidseat weight
Core Design Contradiction:
ProductivityVSWeight of moving object

Solution Approach 1:

The patent changes from metal wires to nylon cords, which are lighter in weight and require less frequent maintenance. This parameter change simultaneously addresses both the productivity concern (reduced maintenance frequency) and the weight concern (lighter materials).

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP3239050B1Lock mechanism for aircraft passenger seat
Publication Date: 2019.05.22 JAMCO CORPORATION
  • EP3239050B1 patent drawingFigure 1
  • EP3239050B1 patent drawingFigure 2
  • EP3239050B1 patent drawingFigure 3(a)~3(c)

AI summary

In order to improve ease of maintenance of an aircraft passenger seat, the aircraft passenger seat 100 is adapted to be changeable between an upright position and a bed mode position at which the backrest is folded forward. A mechanism for locking the seat at each of the positions is provided with lock pins 350 provided on both sides of the backrest, a handle unit 200 mounted to a rear face of the backrest, and two wires 300 for connecting the handle unit 200 and the lock pins 350. A structure for connecting the wires 300 to the handle unit 200 is improved to facilitate the maintenance of the wires and to make the handle unit lightweight.