Fitting Device V-Scissor Holding Mechanism Reduces Pivot Bearing Stress
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Solution Overview
Problem
Existing fitting arrangements for windows and doors face high tensile stress on pivot bearings due to the weight of the sash, leading to reduced wear resistance, reliability, and smooth operation, especially in large installations where the lever arm between supports is short.
Innovation Solution
A fitting arrangement with a holding device connected independently to the frame part, forming a V-scissor mechanism that absorbs forces eccentrically to the pivot bearing, providing a longer lever arm and reducing material stress, featuring a holding element and connecting element that rotate about different axes for stable force dissipation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the pivot bearing forms the rear support of the link, then the structure is simple, but the lever arm between supports becomes short causing high tensile stress on the pivot bearing
Solution Approach 1:
The support function is segmented into two independent components: the pivot bearing (providing rotational support) and the holding device (providing separate support at a different location). This segmentation allows the holding device to be positioned independently to optimize the lever arm length, thereby reducing tensile stress on the pivot bearing while maintaining structural simplicity through modular design.
2Device complexity
If the front support is located near the pivot bearing, then the base plate design is simple, but the lever arm becomes short reducing wear resistance and reliability
Solution Approach 1:
The holding device acts as an intermediary element between the link and the base plate, providing support at an optimized location that maximizes the lever arm. This intermediary component transfers the load from the link to the base plate through a more favorable mechanical arrangement, reducing stress concentrations and improving wear resistance and reliability without complicating the base plate design.
3Stress or pressure
If the holding device is connected independently to the frame part, then the lever arm is longer reducing stress, but the device complexity increases
Solution Approach 1:
The holding device implements local quality by concentrating the support function at a specific location optimized for lever arm length, while other parts of the structure maintain their original simple designs. This localized approach to improving stress distribution allows the holding device to have a specialized function without requiring complex changes throughout the entire structure.
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 significantly enhances wear resistance, reliability, and ease of movement by effectively distributing the weight of the sash into the frame part with reduced stress on the pivot bearing, ensuring long-term reliability and smooth operation.
Implementation Method 1
absorbs a force exerted on the link by the weight of the sash
Implementation Method 2
The link is rotatably mounted about a first axis of rotation about a pivot bearing
Data Source
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AI summary
The arrangement has a control arm (16) supported at a frame part (10) by two supports. One of the supports is located closer to a frame-side end (16a) of the control arm than the other support. The former support is formed by a holding device (28) V-scissors, of a frame part (10). The holding device is connected with the frame part independent of a rotary bearing (20). The holding device engages at the control arm and receives force, which is exerted on the control arm by a weight of a wing, in a rotational position of the control arm.