Backrest Joint Mechanism With Crown Gear for Stable Angle Adjustment

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Solution Overview

Problem

Existing connection joints for adjusting the angle of sun loungers and deckchairs are complex, costly, and bulky, affecting the structure's appearance and stability, and lack resistance to external agents like water and salt.

Innovation Solution

A compact joint mechanism using a fixed crown gear, mobile ring nut, and spacer ring with elastic ring-nut stressing means, allowing adjustable angular positioning of the backrest while providing stability and sealing against external agents.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stability of the object's composition

If a complex joint mechanism is used to adjust backrest angle and provide support function, then the backrest positioning stability is improved, but the device complexity and production cost increase

Engineering Contradiction:
Improvebackrest positioning stabilityVSAvoidjoint complexity
Core Design Contradiction:
Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The patent combines the adjustment mechanism and support function into a single integrated joint assembly. The mobile ring nut serves dual purposes: it adjusts the backrest angle by engaging with the fixed crown gear, and simultaneously provides support function when positioned in the support groove. This merging of functions reduces the number of separate components needed while maintaining both positioning stability and support capability.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The joint mechanism is designed with multi-functionality: the mobile ring nut can operate in different positions to provide both adjustment and support functions, the fixed crown gear serves as both a positioning mechanism and a support surface, and the entire joint assembly can function as both an angle adjustment device and a support structure. This universal design reduces overall system complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Strength

If a bulky joint structure is used to ensure stability and support function, then the mechanical strength is improved, but the joint dimensions and aesthetic appearance are worsened

Engineering Contradiction:
Improvejoint strengthVSAvoidjoint volume
Core Design Contradiction:
StrengthVSVolume of moving object

Solution Approach 1:

The joint components are designed with nested arrangements where the mobile ring nut fits within the confines of the fixed crown gear structure, and the support groove is integrated into the existing joint geometry. This nesting approach maximizes structural strength while minimizing the overall volume and visual profile of the joint assembly.

Inventive Principle:
Principle #7Nested doll (Nesting)

3Ease of manufacture

If traditional joint materials and structures are used, then the manufacturing ease is improved, but the resistance to external agents like water and salt is worsened

Engineering Contradiction:
Improvejoint manufacturabilityVSAvoidresistance to water and salt
Core Design Contradiction:
Ease of manufactureVSObject-affected harmful factors

Solution Approach 1:

The joint components are designed to utilize composite material properties, combining materials that offer both ease of manufacturing and resistance to environmental factors. The fixed crown gear and mobile ring nut can be manufactured from corrosion-resistant materials or coated with protective layers that maintain manufacturability while providing protection against water, salt, and dust in outdoor environments.

Inventive Principle:
Principle #40Composite materials

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The joint allows for adjustable and stable backrest positioning with minimal impact on the structure's appearance, maintaining stability without additional support and resisting environmental factors like water and salt, while being compact and cost-effective.

Implementation Method 1

elastic ring-nut stressing means

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP3047755B1Connection joint
Publication Date: 2018.05.09 SCASSA G & F DI SCASSA FAB &C SNC
  • EP3047755B1 patent drawingFigure 1
  • EP3047755B1 patent drawingFigure 2
  • EP3047755B1 patent drawingFigure 3~5

AI summary

A connection joint between a first frame (4) and a second frame (5) comprises a fixed half-joint (12) and a mobile half-joint (14). The fixed half-joint and mobile half-joint have respective mutual coupling portions (16, 17) which jointly delimit a joint seat (18) in which an adjustment mechanism (20) of the angular position of one frame in relation to the other is housed. In a general embodiment, the adjustment mechanism comprises a fixed crown gear (26) integral with the coupling portion (16) of the fixed half-joint, a mobile ring nut (28) integral in rotation with the mobile half-joint and suitable to engage the fixed crown gear in steps, a spacer ring (30), substantially suitable to define different axial positions of the mobile ring nut, and elastic ring-nut stressing means (32) elastically influencing the axial position of the mobile ring nut.