Push Rod Window Fitting With Pinion Locking Against Rod Deformation

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Solution Overview

Problem

Existing window locking mechanisms suffer from misinterpretation of locking states due to haptic feedback and complex designs, leading to unnecessary force application and potential deformation, and lack efficient integration with existing handles.

Innovation Solution

A locking device that engages with a locking element in a circumferential recess of the pinion, operated by an electric actuator, allowing immediate locking at the point of force application and minimizing mechanical load, with a compact design that integrates into the pushrod drive housing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a locking mechanism is associated with the drive rod fitting, then the locking function is achieved, but the user can still exert force on the drive rod via the operating handle, resulting in elastic and potentially plastic deformation

Engineering Contradiction:
Improvelocking functionVSAvoiddrive rod
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

A locking element is introduced as an intermediary component between the operating handle and the drive rod. This locking element can be positioned in a circumferential recess of the pinion to prevent further rotation of the drive rod after locking, thereby eliminating the harmful force transmission that causes deformation while maintaining the locking function.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The locking element is designed to engage with the circumferential recess of the pinion before the drive rod can be elastically or plastically deformed. By establishing this preliminary mechanical constraint, the system prevents the harmful range of motion and force application that would otherwise occur during the locking process.

Inventive Principle:
Principle #10Preliminary action

2Ease of operation

If the locking device extends across the entire neck section of the handle into the adjoining rosette, then the locking mechanism is released without lock cylinder, but the design becomes complex with large footprint and low axial rigidity

Engineering Contradiction:
Improvelocking mechanism releaseVSAvoidclutch mechanism
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The locking element is extracted from the complex clutch mechanism and simplified to a standalone component that engages with the circumferential recess of the pinion. This extraction eliminates the need for the entire clutch mechanism extending into the rosette, reducing device complexity and footprint while maintaining the ability to release the locking mechanism without a lock cylinder.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

Instead of having the locking mechanism extend into the rosette and use the handle neck section, the invention inverts the approach by placing the locking element directly in the pinion's circumferential recess. This inversion simplifies the mechanical path and reduces the footprint while achieving the same operational result.

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

3Strength

If additional clearances for receiving the locking device on the sash are provided, then the locking device can be designed robust and bulky, but the installation space requirement increases

Engineering Contradiction:
Improvelocking deviceVSAvoidinstallation space
Core Design Contradiction:
StrengthVSArea of stationary object

Solution Approach 1:

The locking device is merged with the existing pushrod drive housing, utilizing the available installation space within the existing structure. By combining these functions, the locking device can be designed robustly without requiring additional clearances or increasing the overall installation footprint.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The pushrod drive housing serves multiple functions: it houses the drive mechanism and simultaneously provides the mounting structure for the locking device. This multi-functionality allows the locking device to be robust without requiring separate installation space, as it integrates into the existing housing structure.

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

Data Source

PatentEP4650553A1Fitting of a window or a door
Publication Date: 2025.11.19 SIEGENIA AUBI KG
  • EP4650553A1 patent drawingFigure 1~2
  • EP4650553A1 patent drawingFigure 3~4
  • EP4650553A1 patent drawingFigure 5~7

AI summary

The invention relates to a fitting for a window or door comprising a push rod fitting cooperating with a handle, wherein the handle engages with a square in a drive connection with a pinion (3) of a push rod drive (1), wherein the pinion (3) is rotatably mounted in a housing (4) and meshes with a toothing (9) of a movable drive rod (10), wherein the push rod fitting consists of at least one drive rod (10) to which at least one locking bolt (11) is assigned which can be moved into an unlocked position and a locked position by a rotation of the handle, wherein the drive rods (10) can be blocked in their movement by a locking device (14). In order to achieve a blocking of the connecting rods in the immediate vicinity of the introduction of the drive energy, it is provided that the locking device (14) engages with a locking element (20) in a circumferential recess (21) of the pinion (3).