Segmented Backrest Chair Design for Dynamic Back Curve Conformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Office chairs lack the comfort and adjustable features of leisure chairs, which are bulky, slow to adjust, and costly, making it difficult to incorporate leisure chair functionality into a compact and cost-effective design for office use.
Innovation Solution
A chair design featuring an upper and lower backrest with a rotatable backrest bracket, a transfer rod, and a transmission device that allows the backrests to adjust smoothly and synchronously, mimicking the curvature of a leisure chair, using a linkage mechanism to reduce the angle between the backrests and enhance comfort.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If gas rods are used inside the backrest for adjustment, then the backrest can be adjusted, but the adjustment is slow, bulky, and costly
Solution Approach 1:
The patent removes the gas rod mechanism from inside the backrest and extracts only the essential adjustment function. The backrest bracket is made rotatable on the base, and the upper backrest is made rotatable on the backrest bracket, eliminating the need for gas rods while maintaining adjustment capability. This extraction principle resolves the contradiction by removing the bulky adjustment mechanism while preserving the core function.
Solution Approach 2:
The patent replaces the gas rod mechanical system with a pure rotational linkage system. Instead of using gas pressure for adjustment, the invention uses rotational joints and linkage mechanisms (transfer rod connecting lower and upper backrests) to achieve smooth adjustment. This substitution eliminates the need for gas rods, reducing size and cost while improving adjustment speed.
2Adaptability or versatility
If a single backrest is used, then the structure is simple, but it cannot conform to the back curve like leisure chairs
Solution Approach 1:
The patent divides the single backrest into two segments: an upper backrest and a lower backrest. The upper backrest can rotate relative to the lower backrest via the transfer rod linkage, allowing the backrest assembly to conform to the natural curve of the human back. This segmentation enables leisure chair-like comfort while maintaining a more compact structure suitable for office use.
Solution Approach 2:
The patent makes the backrest structure dynamic by allowing the upper backrest to rotate relative to the lower backrest. This dynamic adjustment capability enables the backrest to adapt to different sitting positions and back curves, replicating the comfort of leisure chairs. The rotational linkage mechanism provides smooth, continuous adjustment without requiring bulky components.
3Ease of operation
If the upper backrest rotates relative to the backrest bracket, then the angle between upper and lower backrests is reduced to envelop the back, but the mechanism becomes more complex
Solution Approach 1:
The patent merges the rotation control of the upper backrest with the existing backrest bracket rotation mechanism. The transfer rod connects the lower backrest to the upper backrest, and as the backrest bracket rotates, the transfer rod automatically drives the upper backrest to rotate through the linkage action. This merging of functions eliminates the need for separate transmission devices, reducing complexity while maintaining smooth adjustment.
Solution Approach 2:
The linkage mechanism between the transfer rod and the rotatable backrests creates a self-driven system. When the backrest bracket is tilted backward, the transfer rod automatically moves relative to the backrest bracket, which in turn automatically drives the upper backrest to rotate. This self-service mechanism eliminates the need for external transmission devices, reducing structural complexity while ensuring smooth, synchronized rotation.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention provides a chair with improved comfort, comprising an upper backrest (1), a lower backrest (2), a backrest bracket (3), and a base (4). The backrest bracket (3) is pivotally mounted on the base (4), and the upper backrest (1) is pivotally mounted on the backrest bracket (3). The lower backrest (2) is pivotally connected to the upper backrest (1). Additionally, a transfer rod (5) and a transmission device are provided between the upper backrest (1) and the base (4). When the backrest bracket (3) tilts backward, the movement of the transfer rod (5) relative to the backrest bracket (3) drives the upper backrest (1) to rotate relative to the backrest bracket (3), thereby reducing the angle between the upper backrest (1) and the lower backrest (2) to wrap around the user's back, achieving the function of wrapping along the back curve and improving comfort.