Intermediate Arm Assembly Strength Stiffness Roof Window

Solution Overview

Problem

Existing dual-function skylight windows lack sufficient strength and stiffness in their intermediate arm assemblies, which can lead to reduced opening angles and increased risk of collision with the window frame during tilting, and inadequate support for the sash during pivoting.

Innovation Solution

The intermediate arm assembly is composed of two sections, a channel section and a Z-bar section, connected via clinch joints and hinges, forming a box-like structure that enhances strength and stiffness, allowing for increased opening angles and secure attachment of the sash lifting support mechanism, with an articulated quadrilateral tilting hinge and adjustment wedge for precise positioning.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If intermediate arms are made from single open sections (bent sheet metal profiles), then the structure is simple and easy to manufacture, but the strength and stiffness are insufficient leading to reduced opening angles and increased collision risk

Engineering Contradiction:

Improveease of manufactureVSAvoidstrength

Core Design Contradiction:

Ease of manufactureVSStrength

Solution Approach 1:

The intermediate arm is divided into two separate sections (first section and second section) that are connected together. Each section can be manufactured separately using simple bent sheet metal profiles, maintaining ease of manufacture, while their combination creates a structure with enhanced strength and stiffness that prevents frame collision during window opening operations.

Inventive Principle:

Principle #1Segmentation

2Device complexity

If intermediate arms are made from single open sections (bent sheet metal profiles), then the structure is simple, but the stiffness is insufficient leading to reduced opening angles and increased collision risk

Engineering Contradiction:

Improvedevice complexityVSAvoidstiffness

Core Design Contradiction:

Device complexityVSStability of the object's composition

Solution Approach 1:

The intermediate arm is divided into two separate sections (first section and second section) that are connected together. Each section can be manufactured separately using simple bent sheet metal profiles, maintaining ease of manufacture, while their combination creates a structure with enhanced strength and stiffness that prevents frame collision during window opening operations.

Inventive Principle:

Principle #1Segmentation

3Adaptability or versatility

If intermediate arms rest on window frame during pivoting, then the structure allows pivoting function, but the support for sash is inadequate

Engineering Contradiction:

ImprovefunctionalityVSAvoidsupport reliability

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The intermediate arm is divided into two separate sections (first section and second section) that are connected together. Each section can be manufactured separately using simple bent sheet metal profiles, maintaining ease of manufacture, while their combination creates a structure with enhanced strength and stiffness that prevents frame collision during window opening operations.

Inventive Principle:

Principle #1Segmentation

Data Source

PatentEP3348763B1Intermediate arm assembly for a dual-function roof window

Publication Date: 2020.04.22 FAKRO PP SPOLKA Z O O

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AI summary

An intermediate arm is composed of at least two sections, including a channel section (1) having shelves (12, 13) of various widths, and a Z-bar (2). The lower shelves (12, 22) of these two sections face each other and the opposite upper shelves (13, 22) of the two sections are adjacent to one another and are inseparably connected, especially by clinch connection. The intermediate arm has an articulated connection to the trough (3) by means of two connectors (51, 52), which together with the trough (3) and the intermediate arm form an articulated quadrilateral. The intermediate arm assembly has also a sash lifting support mechanism, whose slider (61) moves in the trough (3) and is connected by a support bracket (62) to the Z-bar (2) of the intermediate arm.