Zero-Wall Linkage Mechanism for Elevated Seat Pitch in Recliners
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Solution Overview
Problem
Existing seating units do not allow for sufficient seat pitch adjustment in the fully-reclined position, limiting the ability to achieve a 'zero-gravity' position that provides enhanced comfort by further elevating the ottoman and seat angle.
Innovation Solution
A linkage mechanism with adjustable pivot points and interconnected links that allow for a more dramatic seat pitch increase from 13 to 24 degrees in the fully-reclined position, coupled with a motorized drive system to control the movement between closed, extended, reclined, and fully-reclined positions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If existing linkage mechanisms are used, then the seating unit can achieve closed, extended, and reclined positions, but the seat pitch only increases slightly (about 5 degrees) in the fully-reclined position, limiting comfort
Solution Approach 1:
The patent applies the dynamics principle by making the linkage mechanism adjustable and reconfigurable. The linkage includes adjustable links that can be repositioned to change the mechanical advantage and movement characteristics of the system. This allows the seat pitch to dynamically increase to 24 degrees or more in the fully-reclined position while still maintaining the closed, extended, and reclined positions, thus resolving the contradiction between ease of operation and adaptability.
2Ease of operation
If the ottoman is elevated further in the fully-reclined position to achieve zero-gravity, then user comfort is enhanced, but the device complexity increases
Solution Approach 1:
The patent applies the universality principle by designing a multi-functional linkage mechanism that performs multiple functions: it provides the closed position, extended position, reclined position, and fully-reclined zero-gravity position all through a single integrated system. The adjustable links serve multiple purposes in controlling the movement of the seat, backrest, and ottoman, thereby enhancing user comfort without proportionally increasing device complexity.
Solution Approach 2:
The patent applies segmentation by dividing the linkage mechanism into multiple adjustable links (front lift link, rear lift link, connector link, etc.) that can be independently positioned. This segmentation allows precise control over the ottoman elevation and seat pitch adjustment, enabling the zero-gravity position to be achieved through coordinated movement of discrete link segments rather than a monolithic complex mechanism.
3Shape
If the seat pitch is increased dramatically to 24 degrees or more, then a zero-gravity position is achieved with ottoman elevated further above the support surface, but the linkage mechanism requires more complex adjustments
Solution Approach 1:
The patent applies parameter changes by providing adjustable links with multiple predetermined positions that can be selected during assembly or operation. The front lift link, rear lift link, and connector link can be adjusted to different parameters (lengths, angles, pivot positions) to achieve the desired 24-degree or greater seat pitch in the fully-reclined position. This parameter adjustability allows the zero-gravity shape to be achieved while simplifying manufacturing through standardized adjustable components rather than custom-designed complex linkages.
Data Source
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AI summary
A metal-to-the-floor linkage mechanism provides backrest recline and ottoman extension for a seating unit. The linkage mechanism has a base and a pair of seat mounting plates that are used to attach a seat to the mechanism. The linkage mechanism comprises a first and a second plurality of links that are each pivotally coupled between the base and a corresponding one of the pair of seat mounting plates. The first and second plurality of links moveably interconnect the base and the seat mounting plates to control movement of the seating unit between closed, TV, reclined and fully-reclined positions. In the fully-reclined position, the seat mounting plates are moved to a position by the first plurality of links and the second plurality of links to place the seat of the seating unit at an angle relative to horizontal of between eighteen and twenty-six degrees.