Window Fitting Stop Mechanism for Anti-Levering Security

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing window and door fittings face challenges in providing enhanced security against break-ins with complex designs that increase assembly effort and do not effectively absorb forces perpendicular to the sash or frame plane.

Innovation Solution

A stop mechanism with a spring-loaded locking bar and releasable latching device is integrated, which engages with the locking element and bolt, allowing the bolt to absorb forces and secure the locking point, even during large relative displacements, using a structurally simple configuration with few components.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a stop is provided opposite the locking element with a spring-loaded locking bar and releasable latching device, then security against break-ins is enhanced and forces perpendicular to the sash plane are absorbed, but the device complexity increases

Engineering Contradiction:
Improvesecurity against break-insVSAvoiddevice complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The locking bar (9) is nested within the stop (1) structure, and the latching device is integrated into the base part (8). The locking bar can engage with locking slots (5, 6) on both sides of the locking engagement, creating a nested configuration that maximizes security within a compact form factor without requiring separate external components.

Inventive Principle:
Principle #7Nested doll (Nesting)

Solution Approach 2:

The stop (1) combines multiple functions into a single integrated component: it provides the locking bar (9) for engagement with locking slots, incorporates a spring-loaded latching device with cover part (7) and base part (8), and positions itself to absorb forces perpendicular to the sash plane. This merging of functions reduces the need for separate security mechanisms.

Inventive Principle:
Principle #5Merging (Combining)

2Reliability

If the locking element is positioned at a small distance from the transverse edge to prevent levering out, then security is improved, but the available rebate clearance is narrowed complicating relative displacement

Engineering Contradiction:
Improvesecurity against leveringVSAvoidease of operation
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The stop (1) is positioned in the rebate area, utilizing the depth dimension of the rebate space rather than consuming lateral clearance. The locking bar (9) extends horizontally to engage locking slots while the stop body is recessed into the rebate, effectively adding security in the lateral dimension without compromising the vertical clearance needed for sash operation.

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

3Reliability

If a complex locking mechanism with multiple components is used to absorb forces perpendicular to the sash plane, then security is improved, but the assembly effort and number of components increases

Engineering Contradiction:
Improveforce absorption capabilityVSAvoidassembly effort
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The stop (1) is divided into two main segments: the base part (8) that is stationary and mounted on the sash, and the cover part (7) that contains the movable locking bar (9) and spring-loaded latching device. This segmentation allows for simplified manufacturing and assembly, where the base part can be pre-installed and the cover part attached with the latching mechanism.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The stop (1) is designed as a universal component that can be applied to various window and door configurations. The locking bar (9) can engage with locking slots in different positions, and the overall design works with standard espagnolette fitting arrangements, reducing the need for custom-designed components for different applications.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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 enhances security by preventing the locking element from being levered out and absorbs forces perpendicular to the sash or frame plane, reducing the risk of break-ins while maintaining ease of assembly and operation.

Implementation Method 1

a spring-loaded locking bar and releasable latching device for the locking bar that is spring-loaded in the direction of the locking engagement

Methodology Applied
Scientific EffectElastic deformation: Elasticity

Data Source

PatentEP3516135B1Fitting
Publication Date: 2020.04.22 SIEGENIA AUBI KG
  • EP3516135B1 patent drawingFigure 1~3
  • EP3516135B1 patent drawingFigure 4~5
  • EP3516135B1 patent drawingFigure 6~7b

AI summary

The invention relates to a fitting for a window or a door, wherein a locking element (2) is provided for engaging with a lock-engaging element (3) in a displacement direction running along a rebate. When in the locked position, said locking element engages in a laterally open locking slot (5) in the lock-engaging element (3), the locking slot running along the rebate. A stationary stop (1) is associated with and a short distance from the locking element (2) on the transverse edge of the lock-engaging element (3) opposite the locking slot (5). The aim of the invention is to obtain an improved design which is easy to mount and does not have an adverse effect on the normal operation of the fitting, but still improves security during an attempted break-in. To achieve this aim, the stop (1) has a detachable detent mechanism for a lock (9) spring-loaded in the direction of the lock-engaging element (3), and the detent mechanism is triggered when the lock-engaging element (3) contacts the stop (1).