Flexible support device for chair back tilting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing flexible tilting support systems for chair backs face challenges in achieving optimal flexibility and stability, requiring excessive force for operation and being prone to jamming and structural imbalance due to complex force transmission mechanisms.
Innovation Solution
A flexible support device comprising a base with pivotally connected driving members, a spring supported by a shaft with adjustable compression, and a pulling rod that compresses the spring to provide flexible support, allowing for adjustable elasticity and reduced effort in tilting the chair back, with a mechanism that increases torque and minimizes structural stress.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the driving member directly compresses the spring to provide flexible support, then the chair back obtains flexibility, but a larger force is required due to short distance between effort point and spring
Solution Approach 1:
The patent introduces a rotational dimension by pivoting the driving member about a point, converting linear compression into rotational motion. This creates a torque arm that extends the effective distance between the user's input force and the spring compression point, providing mechanical advantage while maintaining flexible support.
Solution Approach 2:
The driving member acts as an intermediary lever between the user's input force and the spring. By positioning the pivot point strategically, the driving member amplifies the input force through torque, reducing the effort needed to compress the spring while maintaining the desired flexibility.
2Ease of operation
If a link set is used to change force direction between adjusting rod and transmission rod, then force transmission is achieved, but jamming and rotational resistance occur causing malfunction
Solution Approach 1:
The patent removes the link set from the force transmission path entirely, replacing it with a direct pivot connection. This eliminates the intermediate components that were prone to jamming and rotational resistance, simplifying the mechanism and improving reliability.
Solution Approach 2:
The driving member is segmented into distinct functional zones: the pivot point for rotation, the compression zone for spring engagement, and the adjustment zone for flexibility control. This segmentation allows each part to perform its function independently without interference, preventing jamming.
3Ease of operation
If the link set transfers force through one side to the transmission rod, then force transmission is achieved, but unbalance occurs causing deflection and structural damage
Solution Approach 1:
The patent employs asymmetric positioning of the pivot point and spring engagement point on the driving member, creating intentional unbalanced moments that are counteracted by the rigid base structure. This asymmetric design allows for more efficient force transmission while the overall symmetric base maintains structural stability.
Solution Approach 2:
The driving member is merged with the base through rigid attachment, creating a unified structural system. This merging ensures that any unbalanced forces are distributed throughout the entire base structure rather than concentrating stress on the transmission rod, preventing deflection and structural damage.
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 comfortable and stable flexible support to the chair back while reducing the effort required for tilting, enhancing usability and preventing structural damage by optimizing the force distribution and adjustable elasticity.
Implementation Method 1
a spring (4) disposed in the base (1)
Implementation Method 2
driving members (2) connected to the chair back A2, wherein the driving members (2) are pivotally connected to the base (1)
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The flexible support device is used for chair back (A2) tilting, which is installed under a cushion (A3). The device includes a base (1), two driving members (2) connected to the chair back (A2), a pulling rod (3) crossing the base (1) and a spring (4) disposed in the base (1). The base (1) is connected to ends of the driving members (2). Two ends of the pulling rod (3) are separately connected to two free ends of the two driving members (2). The pulling rod (3) has a frame (31) encompassing the spring (4). The frame (31) has an action end (311) blocking the spring (4). When the chair back (A2) is pressed to tilt rearward, the driving members (2) are rotated to draw the pulling rod (3) to move toward the chair back (A2), and the action end (311) of the frame (31) is driven to compress the spring (4) so as to make the chair back (A2) flexibly supported.