Skylight Opening Mechanism with Rotating Lever Arms

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Solution Overview

Problem

Conventional skylight opening mechanisms face challenges such as difficulty in cleaning, high wind resistance, and limited size due to robust support structures, while louvre windows compromise visibility and are not suitable for all skylight sizes.

Innovation Solution

A skylight opening mechanism using rotating lever arms that lift the window sash out of the roof plane, allowing easy access for cleaning and reducing wind resistance, with the ability to open the sash completely or almost completely, and featuring a parallelogram guidance for stable movement, optionally powered by a motor.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If hydraulic springs are used to support the window sash, then the sash can be opened against gravity and secured in the open position, but the mechanism becomes heavy and expensive, and the outside of the window sash becomes difficult to clean

Engineering Contradiction:
Improveopening the sash against gravityVSAvoidweight of support mechanism
Core Design Contradiction:
Ease of operationVSWeight of moving object

Solution Approach 1:

The patent replaces the hydraulic spring mechanism with a lever arm system that uses mechanical advantage and gravity to its advantage. The lever arms are arranged so that gravity assists the opening motion rather than opposing it, eliminating the need for heavy hydraulic springs while still enabling the sash to be opened against gravity and secured in the open position

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

Instead of using hydraulic springs to push the sash open against gravity, the invention inverts the approach by using lever arms positioned such that gravity naturally assists the opening motion. The lever arms are configured so that when rotated, they lift the sash using mechanical advantage while gravity provides the closing force, eliminating the need for active support during opening

Inventive Principle:
Principle #13The other way round (Inversion)

2Reliability

If hydraulic springs are used to support the window sash, then the sash can be secured in the open position, but the mechanism becomes robust and heavy to withstand high wind speeds

Engineering Contradiction:
Improvewithstanding high wind speedsVSAvoidweight of support mechanism
Core Design Contradiction:
ReliabilityVSWeight of moving object

Solution Approach 1:

The patent replaces the heavy hydraulic spring mechanism with a lever arm system that uses mechanical advantage. The lever arms are positioned to create favorable force moments that naturally resist wind loads on the open sash, providing robust wind resistance without the need for heavy construction

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The lever arm mechanism is designed to create a near-balanced system where the gravitational force on the sash is counterbalanced by the lever arm geometry. This creates a system that is naturally stable and resistant to external forces like wind, without requiring overly robust and heavy construction

Inventive Principle:
Principle #12Equipotentiality

3Device complexity

If the window sash is turned via a rotary axis on the upper side, then the opening mechanism is simple, but the outside of the window sash becomes difficult to access for cleaning

Engineering Contradiction:
Improvesimplicity of opening mechanismVSAvoidaccessibility for cleaning
Core Design Contradiction:
Device complexityVSEase of operation

Solution Approach 1:

The patent transitions from a static rotary axis opening mechanism to a dynamic lever arm system. The lever arms are positioned to rotate in a plane that allows the sash to be lifted and moved outward, dynamically changing the sash position during opening to provide cleaning access while maintaining mechanical simplicity

Inventive Principle:
Principle #15Dynamics

4Object-affected harmful factors

If louvre windows with multiple smaller sashes are used, then the surface area exposed to wind is reduced and cleaning becomes easier, but the view through the skylight is disturbed

Engineering Contradiction:
Improvewind surface area and cleaning accessVSAvoidview through the skylight
Core Design Contradiction:
Object-affected harmful factorsVSIllumination intensity

Solution Approach 1:

The patent applies segmentation by dividing the single large sash into multiple smaller sash sections, each with its own lever arm mechanism. This allows individual sections to be opened independently, reducing the wind-exposed surface area and improving cleaning access while maintaining overall visual continuity when closed

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The segmented sash sections are designed to move dynamically when opened, lifting and rotating outward on lever arms. This dynamic motion allows the sash to clear the roof plane when open, providing cleaning access and reduced wind exposure while maintaining a flush, unobtrusive appearance when closed

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP2843149B1Skylight with opening mechanism
Publication Date: 2018.11.07 STEBLER HLDG AG
  • EP2843149B1 patent drawingFigure 1A~1D
  • EP2843149B1 patent drawingFigure 2A~2C
  • EP2843149B1 patent drawingFigure 3A~3B

AI summary

A roof window for a building comprising a window frame (4), a window sash (3), and an opening mechanism for the window sash (3). The window frame (4) is designed for installation in a building roof. The opening mechanism is designed such that the window sash can be moved from a closed state to an open state. The opening mechanism has a first lever arm between a first side (2.1) of the window sash (3) and a first side (2.1) of the window frame (4), and at least a second lever arm (5.2) between a second side (2.2) of the window sash (3) and a second side (2.2) of the window frame (4), wherein the lever arms (5.2) are rotatably mounted on the window sash (3) and the window frame (4), such that the opening mechanism is designed to move the window sash (3) laterally out of the window frame (4) by rotating the lever arms (5.2) along a semicircular path.