Slide Fastener Overlapping Stringer Edges for Water-Tight Sealing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing slide fasteners have a visible gap between stringers in the closed condition, which is aesthetically undesirable and can compromise water-tightness in certain applications.
Innovation Solution
The inner longitudinal edge portions of the stringers project beyond the coupling elements, allowing them to overlap in a substantially overlapped condition when engaged, with optional water-tight coatings on both sides of the tapes to enhance sealing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a continuous coil-like coupling element is affixed to one side of the stringer tapes, then the fastening function is achieved, but a visible gap remains between stringers in the closed condition, causing aesthetic problems and compromising water-tightness
Solution Approach 1:
The invention divides the stringer structure into distinct segments: the tape body and the projecting inner longitudinal edge portions. These edge portions extend beyond the coupling elements to create overlapping sections that seal the gap between stringers, effectively segmenting the function of fastening and sealing.
Solution Approach 2:
The solution adds a dimensional element by extending the inner longitudinal edge portions beyond the plane of the coupling elements. This creates an overlapping three-dimensional structure where edge portions from opposite stringers meet and interlock, eliminating the gap in the closed condition while maintaining the fastening function.
2Shape
If inner longitudinal edge portions of stringers are extended to overlap when engaged, then aesthetics and water-tightness are improved, but the device complexity increases
Solution Approach 1:
The inner longitudinal edge portions serve multiple functions simultaneously: they provide the overlapping structure for aesthetic closure, create a sealing interface for water-tightness, and maintain structural integrity during fastening and unfastening operations. This multi-functionality reduces the need for additional separate components.
Solution Approach 2:
The edge portions are constructed from the same tape material as the rest of the stringer body, maintaining material homogeneity. This avoids introducing different materials or complex composite structures, thereby minimizing device complexity while achieving the desired overlapping configuration.
3Reliability
If water-tight coatings are applied on both sides of the tapes, then water resistance is enhanced, but manufacturing complexity and cost increase
Solution Approach 1:
The water-tight coatings are applied to the tapes during the manufacturing process before the coupling elements are attached and before the final assembly. This preliminary coating application ensures complete coverage of both sides of the tapes, including edge portions, and eliminates the need for post-assembly coating operations, thereby simplifying the overall manufacturing process.
Solution Approach 2:
The invention specifies particular coating materials (polymer materials such as polyurethane) with defined properties to achieve water-tightness. By selecting coatings with appropriate viscosity, drying time, and adhesion characteristics, the manufacturing process is optimized for ease of application while ensuring effective water resistance.
Data Source
AI summary
The slide fastener includes a pair of stringers, each including a flexible tape having first and second sides facing in opposite directions, and outer and inner longitudinal edges, and coupling elements attached to the first side of the tape, for engagement with corresponding coupling elements of the tape of the other stringer. In the disengaged condition of the coupling elements, inner longitudinal edge portions of the stringers project beyond the respective coupling elements toward the other stringer, to an extent such that when the coupling elements are engaged with each other, the inner longitudinal edge portions of the stringers are engaged with one another in a substantially overlapped condition.