Pocketed spring unit and method of manufacture
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for manufacturing pocketed spring units, such as those used in mattresses, rely heavily on adhesive to hold the springs together, which increases production costs and complicates recycling due to the presence of adhesive in the final product.
Innovation Solution
A resilient unit comprising a plurality of pocketed resilient elements joined to a common elastic cover sheet using welding or adhesive, where the cover sheet is preferably made of elastic material and extends transversely to the compression axes of the elements, allowing for reduced adhesive usage and improved recyclability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If adhesive is used to hold strings of pocketed springs together to form a unit, then the structural integrity and strength of the unit is improved, but the manufacturing cost increases and recyclability deteriorates
Solution Approach 1:
The patent extracts and eliminates adhesive from the pocketed spring unit construction. Instead of using adhesive to join strings of pockets to the end fabric, the invention uses mechanical interlocking through loops formed from the end fabric that engage with the pockets themselves, completely removing the need for adhesive and its associated costs and recycling issues.
Solution Approach 2:
The patent introduces loops formed from the end fabric as an intermediary mechanical connector between the strings of pockets. These loops act as mediators that mechanically interlock with the pockets without requiring adhesive, providing structural integrity through pure mechanical means.
2Strength
If adhesive is used extensively to join strings and form the unit, then the structural integrity is improved, but the recyclability of the unit deteriorates
Solution Approach 1:
The patent completely extracts adhesive from the construction process, eliminating the harmful substance that prevents recycling. The entire unit becomes composed of mechanically interconnected fabric and spring elements that can be separated and recycled without chemical contamination.
Solution Approach 2:
The patent enables easy discarding and recovering of components through mechanical disassembly. The loops and pockets can be undone or separated without chemical bonds, allowing fabric and spring components to be recovered and reused or recycled independently.
3Device complexity
If adhesive is used to hold strings together, then the manufacturing process is simplified, but the manufacturing cost increases
Solution Approach 1:
The patent removes adhesive application equipment, dispensing systems, and curing processes from the manufacturing line. The mechanical loop-based joining method uses standard fabric manipulation and sewing or knitting techniques already present in textile manufacturing, reducing equipment complexity and cost.
Solution Approach 2:
The end fabric loops serve themselves as both the joining mechanism and the structural element. The same fabric that forms the end of the unit automatically creates the loops that join strings together, eliminating the need for separate adhesive application steps and reducing manufacturing complexity.
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
This approach reduces adhesive usage, lowers manufacturing costs, and enhances recyclability while providing improved comfort and resilience through the elastic cover sheet, which can be applied to the unit's surfaces or wrapped around it, maintaining structural integrity and user comfort.
Implementation Method 1
a common cover sheet of elastic material
Implementation Method 2
the pocketed resilient elements are joined to a common cover sheet of elastic material, preferably by welds
Data Source
AI summary
A resilient unit has strings of individual coil springs (not shown) inside pockets 120 are arranged in an array. The strings together form a spring unit and are each secured to a common cover sheet S, which comprises a non-woven elastic fabric. It is welded ultrasonically or thermally whilst under tension in one or both of its major dimensions—i.e. in-plane—to the pockets 120, the material of which is substantially inelastic and non-woven. In this example the welds, labelled W, are located substantially centrally with respect to the generally circular end surfaces of the pockets.