Foldable chair
Solution Overview
Problem
Conventional foldable chairs provide inadequate support for the user's head or back, as the support unit and backrest cover are spaced apart, limiting comfort.
Innovation Solution
A foldable chair with a chair frame mechanism and cushion mechanism, featuring a movable seat and cushion pad that can be adjusted to support the user's lumbar or neck, and a spine rod that allows the backrest unit to be inclined and folded, enhancing user comfort and reducing the chair's size.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the support unit and backrest cover are spaced apart to enable folding operation, then the chair can be folded for compact storage, but the user's head or back cannot be adequately supported
Solution Approach 1:
A cushion mechanism is introduced as an intermediary component between the support unit and backrest cover. This cushion mechanism includes a movable seat that can slide along the spine rod and a cushion pad that provides the necessary support surface, mediating the gap between the support unit and backrest cover to enable both folding operation and user support.
Solution Approach 2:
The cushion mechanism is designed to be movable rather than fixed. The movable seat can slide along the spine rod to adjust its position, and the cushion pad can be positioned at different locations along the backrest. This dynamic design allows the cushion mechanism to adapt to different user needs while maintaining the folding capability of the chair.
2Reliability
If a cushion mechanism is added to provide support between the support unit and backrest cover, then user comfort is improved, but the device complexity increases
Solution Approach 1:
The cushion mechanism is segmented into distinct functional components: a movable seat that slides along the spine rod, a cushion pad for support, and connecting elements. This segmentation allows each component to perform its specific function independently while simplifying the overall assembly and maintenance of the mechanism.
Solution Approach 2:
The movable seat serves multiple functions: it provides a sliding mechanism for adjustment, acts as a structural connector between the cushion pad and spine rod, and enables the cushion pad to be positioned at various heights. This multi-functionality reduces the need for additional separate components, thereby limiting the increase in device complexity.
Data Source
AI summary
A foldable chair includes a chair frame mechanism that is operable between an unfolded state and a folded state and that includes a seat unit, a backrest unit, and a support unit. The backrest unit extends from and cooperates with the seat unit to define a seating space when the chair frame mechanism is in the unfolded state. The support unit is mounted to the backrest unit, and includes a spine rod disposed rearwardly of the backrest unit and being upwardly and downwardly movable for driving operation of the chair frame mechanism between the folded state and the unfolded state. A movable seat is sleeved on and slidable along the spine rod. A cushion pad is connected to the movable seat and is disposed between the movable seat and the backrest unit.