Sliding Sash Shifting Mechanism to Prevent Bolt Jamming

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Solution Overview

Problem

Existing displacement devices for sliding sashes in windows and doors suffer from structural complexity, require significant space, and are not cost-effective, especially when dealing with high loads, due to asymmetrical force application causing torque and jamming issues.

Innovation Solution

A relocation device that is mounted circumferentially on both horizontal and vertical stiles of the sash, using a control cam and control bolt mechanism to guide the sash into a closed or open position relative to the frame, with a compact design that minimizes installation space and requires no additional locking elements.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If roller pairs with narrow central section are used for offset movement, then the sliding sash can be moved perpendicular to the frame, but torque is introduced into the bolt causing it to tilt and jam

Engineering Contradiction:
Improvesliding sash movementVSAvoidbolt jamming
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The invention extracts the problematic narrow central section from the design by using a bolt with a substantially U-shaped cross-section instead. This U-shaped cross-section provides sufficient material area to resist torque without introducing the jamming issues associated with narrow sections. The bolt body itself is redesigned to eliminate the weak point rather than adding complex roller bearing structures.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The bolt employs an asymmetric U-shaped cross-section with a rounded outer side and a flat inner side that engages with the guide profile. This asymmetric design allows the flat inner side to provide a stable engagement surface for the guide profile while the rounded outer side distributes lateral loads, preventing the symmetric failure mode that leads to jamming in conventional designs.

Inventive Principle:
Principle #4Asymmetry

2Ease of operation

If wedge-shaped surfaces are used for guide profile engagement, then the sliding sash can be moved perpendicular to the frame, but asymmetrical force application causes torque and stiff operation

Engineering Contradiction:
Improvesliding sash movementVSAvoidforce application mechanism
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The invention creates equipotential force distribution by using a substantially U-shaped bolt cross-section where the flat inner side provides a uniform engagement surface for the guide profile. This design ensures that forces are distributed evenly across the bolt width rather than being concentrated asymmetrically, eliminating the torque generation mechanism present in wedge-shaped designs.

Inventive Principle:
Principle #12Equipotentiality

Solution Approach 2:

The bolt cross-sectional geometry is changed from a narrow or wedge-shaped profile to a substantially U-shaped profile with specific dimensional relationships. The width, height, and curvature radius of the U-shape are optimized to provide adequate material area for stress distribution while maintaining the necessary engagement characteristics for smooth operation.

Inventive Principle:
Principle #35Parameter changes

3Force

If more than two roller pairs are used for high loads, then the device can handle higher forces, but the structure becomes complex and space-consuming

Engineering Contradiction:
Improveload capacityVSAvoidroller bearing structure
Core Design Contradiction:
ForceVSDevice complexity

Solution Approach 1:

The invention segments the load-bearing function across multiple elements: the U-shaped bolt cross-section, the guide profile, and the roller pairs work together as distributed load paths. This segmentation allows the system to handle high loads without requiring an excessive number of roller pairs, as each element contributes to the overall load distribution and stress management.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The rounded outer side of the U-shaped bolt cross-section and the curved engagement surfaces distribute contact stresses more evenly compared to sharp or flat edges. This curvature-based design allows for smoother force transmission and reduces stress concentration points, enabling the system to handle higher loads with fewer components.

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

The device provides a reliable, cost-effective, and aesthetically pleasing solution for sliding sashes, allowing easy installation and adjustment, while ensuring smooth operation and reducing friction and noise, even under high loads.

Implementation Method 1

A relocation device that is mounted circumferentially on both horizontal and vertical stiles of the sash, using a control cam and control bolt mechanism to guide the sash into a closed or open position relative to the frame

Methodology Applied
Scientific EffectMechanical Force: Mechanical Force

Implementation Method 2

When the strip is moved, the entire sliding sash shifts against a fixed guide element due to the engagement of the guide profile, causing the bolt to penetrate the guide element and compressing the spring

Methodology Applied
Scientific EffectSpring compression: Spring

Implementation Method 3

When the strip is moved, the entire sliding sash shifts against a fixed guide element due to the engagement of the guide profile, causing the bolt to penetrate the guide element. The roller pairs have a narrow central section on the sliding sash bolt. To move the sliding sash perpendicular to the frame, the guide profile engages a wedge-shaped surface against a wedge-shaped surface of the guide element.

Methodology Applied
Scientific EffectWedge mechanism: Wedge

Implementation Method 4

When closing, the sliding sash is pulled towards the frame, pressing the sash seals against the frame again

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP4473179B1Shifting device for the forced shifting of a leaf, in particular a sliding leaf, of a window or a door
Publication Date: 2026.02.04 SIEGENIA AUBI KG
  • EP4473179B1 patent drawingFigure 1
  • EP4473179B1 patent drawingFigure 2~4
  • EP4473179B1 patent drawingFigure 5~8

AI summary

The invention relates to a shifting device (1) for the forced shifting of a leaf (2), a sliding leaf, of a window or a door (4) relative to a frame (3) of the window or the door (4) in a transverse, in particular perpendicular, direction to the main plane of the window or the door (4), comprising an actuation mechanism (5) which can be arranged on the leaf (2) and which is moveably connected to an actuating rod assembly (7) of the shifting device (1) using a section in the rebate circumferential direction (6). As well as comprising a control element (8) of a control plate (9) on the actuating rod assembly (7) of the shifting device (1), and a control cam (11) or pin, wherein the control plate (9) has a control contour (12) which, with the control bolt (13) arranged on the actuating rod assembly (7) of the shifting device (1), cooperates with the rod assembly of the actuation mechanism (5).