Roof Window Sash Hinge Offset for Cleaning Access

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Solution Overview

Problem

Existing roof windows are difficult to open for cleaning purposes and cause wear on stationary parts, and they lack improved insulating properties and moisture resistance when closed.

Innovation Solution

The top sash member and first hinge connection are positioned such that there is a distance between them in the closed position, allowing the sash to rotate fully above the frame plane, reducing wear and enabling better sealing for improved insulating properties and moisture resistance, with additional space for accessories like screening or ventilation arrangements.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the sash is positioned flush with the frame plane in closed position, then the window has a compact appearance, but the sash cannot be opened fully above the frame plane for cleaning access

Engineering Contradiction:
Improveaccess to outside of pane for cleaningVSAvoidcompact appearance when closed
Core Design Contradiction:
Ease of operationVSShape

Solution Approach 1:

The hinge axis is positioned at a distance from the top sash member in the first direction (perpendicular to frame plane), creating a third-dimensional offset that allows the sash to rotate above the frame plane while maintaining a compact closed position. This spatial arrangement enables the sash to clear the frame plane during opening for cleaning access.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Reliability

If the hinge axis is positioned close to the top sash member, then the window structure is compact, but the sash rotation causes wear on stationary parts

Engineering Contradiction:
Improvewear on stationary partsVSAvoiddistance between hinge axis and top sash member
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The intermediate frame acts as a mediator between the sash and the stationary frame. The first hinge connection connects the sash and intermediate frame to the stationary frame at a distance from the top sash member, while the second hinge connection connects the sash to the intermediate frame. This intermediate structure allows rotation while distributing forces and reducing wear on stationary parts.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Reliability

If the sash and frame have minimal contact area, then the window structure is simpler, but the insulating properties and moisture resistance are reduced

Engineering Contradiction:
Improveinsulating properties and moisture resistanceVSAvoidcontact area between sash and frame
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The sealing arrangement is positioned at the specific location where the sash and stationary frame abut in the closed position. This localized sealing provides enhanced insulating properties and moisture resistance precisely at the critical interface between moving and stationary components, without requiring increased contact area throughout the entire structure.

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP3461965B1A roof window with a sash, a stationary frame and an intermediate frame
Publication Date: 2020.05.13 VKR HOLDING AS
  • EP3461965B1 patent drawingFigure 1
  • EP3461965B1 patent drawingFigure 2
  • EP3461965B1 patent drawingFigure 3

AI summary

A roof window comprising a stationary frame (1) adapted to be built into a structure and having a top frame member (12), two side frame members (13, 14) and a bottom frame member (11), and defining a frame plane, a sash (2) having a top sash member (22), two side sash members (23, 24) and a bottom sash member (21), and defining a sash plane, an intermediate frame (4), at least one first hinge connection (5) for connecting the sash (2) and the intermediate frame (4) to the stationary frame (1), and at least one second hinge connection (6) for connecting the sash (2) to the intermediate frame (4). The top sash member (21) and the first hinge connection (5) is, when seen in a closed position of the sash (2), positioned such that a hinge axis (51) of the first hinge connection (5) and the top sash member (21) is positioned at a distance (A) from one another in a first direction (D1), such that a space (8) is provided between the top sash member (21) and the hinge axis (51) of the first hinge connection (5)