Rollable Fly Screen Tensioning With Curved Edge Equalization

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Horizontally moving screen assemblies face challenges in maintaining a flat appearance due to sagging, as they are unsupported at the bottom edge and experience increasing tension issues when extended, leading to difficulty in operation and potential damage to the screen material.

Innovation Solution

The screen material is cut or formed with a curved top and bottom edge to create a tension equalizer, allowing for balanced tension and preventing sagging, using a combination of springs and pulley systems to maintain even tension across the screen.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the screen material is supported only at two vertical edges for horizontal movement, then the screen can be rolled up about a vertical rod, but the screen material sags under gravity and loses its flat appearance

Engineering Contradiction:
Improveroll-up capabilityVSAvoidflat appearance
Core Design Contradiction:
Ease of operationVSShape

Solution Approach 1:

The screen material is cut or formed with a curved top and bottom edge to create a tension equalizer. This curvature is designed so that when the screen is installed and subjected to gravitational force, the curved edges straighten out, creating even tension across the screen material and preventing sagging, thereby maintaining a flat appearance while preserving roll-up capability

Inventive Principle:
Principle #14Spheroidality (Curvature)

2Area of stationary object

If the screen material is extended across large openings, then the screen covers the required area, but the tension becomes excessive and can damage the screen material

Engineering Contradiction:
Improvecoverage areaVSAvoidmaterial integrity
Core Design Contradiction:
Area of stationary objectVSStrength

Solution Approach 1:

The curved edge design acts as a tension equalizer that distributes the gravitational load more evenly across the screen material. This prevents excessive concentration of tension at any single point, allowing the screen to span large openings without damaging the material while maintaining structural integrity

Inventive Principle:
Principle #14Spheroidality (Curvature)

3Shape

If the screen material is pulled taut to prevent sagging, then the flat appearance is maintained, but the operation becomes difficult and the mechanism may be damaged

Engineering Contradiction:
Improveflat appearanceVSAvoidoperation difficulty
Core Design Contradiction:
ShapeVSEase of operation

Solution Approach 1:

The curved edge configuration creates a mechanical advantage by distributing tension forces more evenly across the screen material and its supports. This reduces peak tension values, making the screen easier to operate while preventing sagging and maintaining a flat appearance throughout the range of motion

Inventive Principle:
Principle #14Spheroidality (Curvature)

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

This solution ensures a flat, taut appearance of the screen material, reducing sagging and operational difficulties, while preventing damage from excessive tension and maintaining a neat roll-up mechanism.

Implementation Method 1

The screen material is cut or formed with a curved top and bottom edge to create a tension equalizer, allowing for balanced tension and preventing sagging

Methodology Applied
Scientific EffectTension distribution through curved geometry: Geometry

Implementation Method 2

using a combination of springs and pulley systems to maintain even tension across the screen

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 3

using a combination of springs and pulley systems to maintain even tension across the screen

Methodology Applied
Scientific EffectMechanical advantage through pulleys: Pulley

Data Source

PatentEP2662522B1Device for tensioning or pre-tensioning a rollable fly screen
Publication Date: 2015.09.09 CENTOR PROD PTY LTD
  • EP2662522B1 patent drawingFigure 1
  • EP2662522B1 patent drawingFigure 2
  • EP2662522B1 patent drawingFigure 3

AI summary

A screen assembly for a window or door opening, the assembly comprising: a flexible screen material having two opposed side edges and an upper edge and a lower edge; a first at least substantially rigid edge member to which one of the two opposed edges of the screen material is attached; a second at least substantially rigid edge member to which the other of the two side edges of the screen material is attached, the screen material able to be wound onto and off the second edge member; and a tensioner to tension the screen material. The upper edge and the lower edge are formed such that when the screen material is under tension, the upper edge and the lower edge are substantially straight.