Adjustment device for a lumbar support of a backrest of a chair or the like
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing lumbar support adjustment systems for chair backrests are complex, costly, and lack intuitiveness, often requiring multiple components and high production costs, while also risking accidental movements during use.
Innovation Solution
A simplified adjustment device using a slider mechanism with stop elements and a wedge-shaped body to move the lumbar support along a horizontal direction, allowing for intuitive depth adjustment with a reduced number of components and enhanced stability, utilizing a plastic material construction without sheet metal or springs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a complex screw-and-nut system is used for lumbar support adjustment, then the adjustment function is achieved, but the device complexity and production cost increase
Solution Approach 1:
The patent merges multiple functions into a single integrated plastic component that combines the adjustment mechanism, locking system, and lumbar support structure. This eliminates the need for separate screw-and-nut systems and reduces the total number of components while maintaining the adjustment function.
Solution Approach 2:
The patent replaces the traditional mechanical screw-and-nut adjustment system with a simplified lever-based mechanism integrated into a plastic component. This substitution reduces complexity while achieving the same adjustment function through a more intuitive operating principle.
2Device complexity
If a simplified adjustment mechanism is used, then the device complexity is reduced, but the reliability and stability may worsen
Solution Approach 1:
The patent incorporates a dynamic locking mechanism that automatically engages and disengages based on the position of the lever. The system transitions between locked and unlocked states dynamically, ensuring stability when positioned and ease of adjustment when the lever is operated.
Solution Approach 2:
The design includes built-in positioning stops and guide features that prevent over-travel and ensure accurate positioning before the locking mechanism engages. This pre-positioning capability enhances reliability by ensuring the lumbar support reaches the correct position before being locked.
3Ease of manufacture
If traditional adjustment systems are used, then the adjustment function is provided, but the production cost and manufacturing complexity increase
Solution Approach 1:
The patent combines multiple previously separate components (adjustment mechanism, locking system, structural elements) into a single integrated plastic component. This merging reduces the number of plastic injection molds required from multiple to just one, significantly simplifying manufacturing and reducing production costs.
Solution Approach 2:
The integrated plastic component performs multiple functions simultaneously: providing structural support, enabling adjustment, and ensuring locking stability. This multi-functionality eliminates the need for separate components that would each require their own molding process, reducing manufacturing complexity.
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 solution provides a reliable, cost-effective, and user-friendly adjustment mechanism that reduces noise and operational complexity, ensuring stable and precise lumbar support adjustments without the risk of accidental movements.
Implementation Method 1
a wedge-shaped body (25), integral with said slider body (21) and arranged facing an abutment (26) integral with at least one portion (10a) of said lumbar support (10), wherein the movement of said wedge-shaped body (25) along said guide (22) is adapted to produce a movement of said lumbar support (10) along said adjustment direction (100)
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An adjustment device for a lumbar support (10) of a backrest (11) of a chair and the like, the backrest (11) comprising a supporting body (2) and at least one lumbar support (10) which is movable, with respect to the supporting body (2), along an adjustment direction (100) which is substantially horizontal and substantially perpendicular to the plane defined by the backrest (11), characterized in that it comprises an actuation element (12) which is movable, with respect to the supporting body (2), along a movement trajectory (101) which lies on a plane that is substantially perpendicular to the adjustment direction (100), between a first position and at least one second position and vice versa, kinematic connection means (20) being provided which act between the actuation element (12) and the lumbar support (10), the kinematic connection means (20) being configured to determine, as a result of the movement of the actuation element (12) between the first position and the at least one second position, a movement of the lumbar support (10) along the adjustment direction (100), the actuation element (12) comprising at least one element (13) which is movable by the user along the movement trajectory (101), the kinematic connection means (20) comprising at least one slider body (21) which is mounted so that it can slide along a guide (22) defined on the supporting body (2) and extending along a substantially vertical direction, the adjustment device (1) comprising, along the extension of the guide (22), a plurality of stop elements (23) which can be selectively engaged by at least one engagement body (24) supported by the slider body (21) in order to define respective locking positions of the slider body (21) along the guide (22) and, consequently, respective positions of the lumbar support (10) along the adjustment direction (100) with respect to the backrest (11).