Insulation Fastener Assembly for One-Way Depth Adjustment
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Solution Overview
Problem
Existing fastening systems for securing insulation layers on roofs, particularly on sheet metal substructures, face challenges in adjustability and tensile load distribution, leading to potential reduction in pull-out forces and stress on the roof membrane during assembly.
Innovation Solution
A fastener assembly comprising a fastener with two opposing threads and a stop mechanism, where the fastener has a right-hand thread near the tip and a left-hand thread near the head, along with a nut that prevents rotational movement of the grommet, allowing for precise depth adjustment without rotating the grommet, thus avoiding stress on the cover film.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If the fastener is adjusted by turning it backward and forth to control tensile load on wood or concrete substructures, then the tensile load can be controlled, but the pull-out strength is negatively affected
Solution Approach 1:
The fastener incorporates a dynamic adjustment mechanism with a nut that can be rotated independently after the fastener is set in the substrate. This allows the anchoring depth to be adjusted dynamically by rotating the nut along the threaded shaft, enabling tensile load control without compromising the fastener's pull-out strength through repeated turning operations
Solution Approach 2:
The fastening system is divided into separate functional components: a fastener with threaded shaft for anchoring, a nut for depth adjustment, and a grommet for load distribution. This segmentation allows the adjustment function to be isolated to the nut component, preventing the need to rotate the entire fastener and thereby preserving pull-out strength while still enabling tensile load control
2Adaptability or versatility
If a hexagonal nut is added to the threaded end of the fastener to improve adjustability, then the anchoring depth can be adjusted, but the grommet's widened head exerts undesirable rotational driving motion on the foil
Solution Approach 1:
The adjustment function is segmented into a separate nut component that threads onto the fastener shaft. This allows the grommet to remain stationary during adjustment operations, as only the nut rotates along the threaded portion of the shaft. The grommet's head does not engage in rotational motion, eliminating the harmful effect on the cover film while preserving depth adjustability
Solution Approach 2:
The nut acts as an intermediary component between the adjustment mechanism and the grommet. It provides the rotational adjustment interface on the threaded shaft while being decoupled from the grommet, preventing the transmission of rotational motion to the grommet and cover film. The intermediary nut enables independent adjustment without adversely affecting the grommet's position or the cover film
3Ease of operation
If the fastener engagement with sheet metal substructure is made narrow to fit the thread, then the fastener can be installed, but the engagement is subjected to high stress
Solution Approach 1:
The fastener system allows for dynamic adjustment of the anchoring depth after installation by rotating the nut along the threaded shaft. This enables optimization of the engagement characteristics with sheet metal substructures, distributing stress more effectively while maintaining installation capability through the adjustable depth mechanism
Data Source
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AI summary
A fastening arrangement comprises a sheath, which is configured as a substantially cylindrical sleeve with a head part, with a hollow-cylindrical shaft and with a conical tip, and also a fastener and a nut, for example made of plastic, which is fitted on the first threaded portion of the fastener. The fastener has two threaded portions, wherein one threaded portion is configured as a right-hand thread and the other threaded portion is configured as a left-hand thread (or vice versa). Moreover, the invention comprises a mounting method for such a fastening arrangement, in which the setting operation (anchoring of the fastener, adjustment of the sheath) can be managed in one step without changing the driving direction of the setting tool.