Rollo Stiffener Hinge for Winding Force Reduction
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Solution Overview
Problem
The existing rollo assemblies used in vehicles for shading roof openings suffer from permanent deformations and markings due to high forces required to straighten stiffeners when winding the rollo screen onto the shaft, which affects the appearance and lifespan of the screen.
Innovation Solution
Incorporating a hinge member extending in the transverse direction between stiffener parts allows them to rotate relative to each other, reducing the force needed for straightening by distributing pressure over a greater length, thus minimizing local pressures and preventing markings.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Shape
If curved stiffeners are used to maintain the rollo screen in a curved shape, then the desired curved shape is achieved, but substantial forces are required to straighten the stiffeners when winding onto the shaft, causing permanent deformations and markings in the rollo screen
Solution Approach 1:
The stiffener is divided into multiple stiffener parts (first stiffener part and second stiffener part) that can rotate relative to each other about a hinge axis. This segmentation allows the stiffener to bend and straighten in a controlled manner, distributing the straightening forces across multiple segments rather than requiring substantial force on a single rigid structure, thereby preventing permanent deformations and markings in the rollo screen.
Solution Approach 2:
The stiffener is designed with dynamic characteristics through the hinge connection, allowing it to transition from a curved shape in the extended position to a straightened position during winding. The hinge member enables relative rotation between stiffener parts, creating a dynamic structure that adapts its shape during operation rather than maintaining a fixed rigid form, thus reducing peak forces during the winding process.
2Productivity
If substantial forces act directly on the stiffeners to straighten them, then the stiffeners can be wound onto the shaft, but these forces cause permanent deformations and markings in the rollo screen that negatively influence appearance and lifespan
Solution Approach 1:
By segmenting the stiffener into multiple parts connected by a hinge, the structure distributes the winding forces across several segments. This prevents concentration of harmful forces at specific points on the rollo screen, eliminating the cause of permanent deformations and markings while maintaining the ability to wind the assembly onto the shaft.
Solution Approach 2:
The hinge member acts as an intermediary element between the stiffener parts, facilitating controlled relative rotation and force distribution. This intermediary mechanism allows the stiffener to straighten during winding through a gradual rotational motion rather than direct force application, protecting the rollo screen from harmful concentrated forces.
3Strength
If the stiffener parts are rigid to maintain the curved shape, then the rollo screen maintains its desired shape, but the stiffness requires substantial forces for straightening
Solution Approach 1:
The stiffener is segmented into multiple parts that maintain individual rigidity to support the curved shape, but are connected through a hinge that allows controlled rotation. This segmentation enables each part to remain stiff for shape maintenance while the overall structure can straighten through rotational movement, reducing the force required compared to straightening a single rigid structure.
Solution Approach 2:
The hinge connection introduces dynamic characteristics to the otherwise rigid stiffener parts. The ability of the stiffener parts to rotate relative to each other transforms the system from a static rigid structure to a dynamic one that can adapt its configuration, allowing shape maintenance during extension and controlled straightening during winding with reduced forces.
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 effectively reduces the forces acting on the rollo screen, preventing deformations and markings, while allowing the stiffeners to maintain the desired curved shape, enhancing the assembly's durability and appearance.
Implementation Method 1
the hinge member moves to a straight position, which also leads to straightening the stiffener parts. Thus, the force for straightening the stiffener parts is generated by the hinge member
Data Source
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AI summary
A rollo assembly comprises a flexible rollo screen (1), a rotatable winding shaft (2) to which a first end of the rollo screen is attached for being wound on or off said winding shaft and two opposite longitudinal guides (3) extending in a longitudinal direction perpendicularly to the winding shaft for guiding opposite sides (4) of the rollo screen. The rollo screen further is provided with longitudinally spaced elongate stiffeners (5) extending substantially in a transverse direction in parallel to the winding shaft (2) between the opposite sides (4) of the rollo screen (1) and attached to the flexible rollo screen, which stiffeners are biased for assuming a curved shape in said transverse direction. Each stiffener (5) comprises two stiffener parts (5') which comprise facing edges and wherein each stiffener (5) further comprises a hinge member (6) extending in said transverse direction and joining said facing edges.