Chair arm assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing chair designs lack adjustable and ergonomic features that allow for optimal user comfort and support, particularly in terms of armrest positioning and lumbar adjustment, which can lead to discomfort and reduced productivity during extended use.
Innovation Solution
A chair assembly incorporating a four-bar linkage mechanism that allows for vertical and horizontal adjustment of armrests and a flexible backrest with a lumbar support system, enabling users to customize their seating position for improved ergonomics and comfort.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a fixed armrest design is used, then the device complexity is reduced, but the adaptability and user comfort are worsened
Solution Approach 1:
The arm assembly is designed with dynamic adjustment capabilities, allowing the armrest to move between fixed and adjustable states. The four-bar linkage mechanism enables vertical adjustment while maintaining structural integrity, and the pivotable connection allows lateral movement, providing adaptability without excessive complexity.
Solution Approach 2:
The arm assembly is divided into multiple independent components: the arm support structure, the four-bar linkage mechanism for vertical adjustment, and the pivotable connection for lateral movement. This segmentation allows each component to perform its specific function independently, achieving adaptability while keeping individual components relatively simple.
2Adaptability or versatility
If a rigid back frame is used, then the structural strength is improved, but the comfort and ergonomic adaptability are worsened
Solution Approach 1:
The backrest incorporates a dynamic lumbar support mechanism that can be adjusted by the user. The lumbar adjustment mechanism allows the support position and firmness to be changed, providing ergonomic adaptability while the overall back frame maintains its rigid structure for strength and stability.
Solution Approach 2:
The back frame is designed with different properties in different regions: the main frame structure is rigid for strength, while the lumbar support region is made adjustable and flexible to provide local customization. This allows the backrest to maintain overall structural integrity while providing ergonomic adaptability in the critical lumbar support area.
3Ease of operation
If adjustable armrests with four-bar linkage are implemented, then the ease of operation is improved, but the device complexity increases
Solution Approach 1:
The four-bar linkage mechanism is designed to be self-operating through user body weight and movement. When the user shifts their weight or moves their arm, the linkage automatically adjusts the armrest position without requiring separate actuators or complex control systems, maintaining ease of operation while limiting complexity growth.
Solution Approach 2:
The four-bar linkage mechanism is integrated with the arm support structure itself, combining the support function and adjustment mechanism into a single unified assembly. This merging eliminates the need for separate adjustment components, reducing overall complexity while maintaining ease of operation through natural user interaction.
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 chair assembly provides enhanced user comfort and support by allowing adjustable armrest positions and customizable lumbar settings, reducing user fatigue and improving overall seating experience.
Implementation Method 1
a four-bar linkage assembly that includes a first linkage member having a first end and a second end, a second linkage member having a first end and a second end, a third linkage member having a first end pivotably coupled to the first end of the first linkage member for rotation about a first pivot point and a second end pivotably coupled to the first end of the second linkage member for rotation about a second pivot point, and a fourth linkage member having a first end pivotably coupled to the second end of the first linkage member for rotation about a third pivot point and a second end pivotably coupled to the second end of the second linkage member for rotation about a fourth pivot point
Implementation Method 2
the lower end of the four-bar linkage assembly is pivotably supported by an arm support structure for pivotable movement of about a fifth pivot point, such that the upper end of the four-bar linkage assembly is movable between a first position and a second position located laterally outward from the first position
Data Source
AI summary
A chair assembly includes a back support arrangement that includes a back frame member and a forwardly-facing surface configured to support a user, a four-bar linkage assembly including a first linkage member, a second linkage member, a third linkage member and a fourth linkage member each pivotably coupled to one another such that the four-bar linkage assembly includes an upper end that is adjustable between raised and lowered positions, and an arm rest assembly supported on the upper end of the four-bar linkage assembly, wherein a lower end of the four-bar linkage assembly is pivotably supported from an arm support structure for pivotable movement such that the upper end of the four-bar linkage assembly is movable between a first position and second position located laterally outward from the first position, and wherein the fifth pivot point is located forwardly of the back frame member.