Coil springs with non-linear loading responses and mattresses including the same
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional coil springs exhibit a linear loading response, which does not provide the same level of support as non-linear foam mattresses, and foam mattresses have mechanical property degradation issues over time and higher production costs.
Innovation Solution
Design of coil springs with a continuous wire forming a plurality of convolutions, where the diameter and pitch of intermediate convolutions are varied to create a non-linear loading response, transitioning from a softer feel upon initial compression to a firmer feel as compression increases, mimicking the support of foam mattresses.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional linear coil springs are used, then the manufacturing cost is low and the structure is simple, but the support comfort is insufficient as they provide linear rather than non-linear support
Solution Approach 1:
The coil spring employs different pitch values in different sections along its length. The first section has a first pitch while the second section has a second pitch that differs from the first, creating non-linear support characteristics. This local variation in geometric parameters allows the spring to provide progressive resistance to compression, improving comfort while maintaining conventional manufacturing methods.
2Ease of operation
If foam mattresses are used to provide non-linear support, then the support comfort is improved, but the mechanical properties degrade over time and production costs increase
Solution Approach 1:
The invention changes the geometric parameters of the coil spring, specifically varying the pitch along different sections. By adjusting the pitch parameter from a first value in the first section to a second value in the second section, the spring achieves non-linear load-deflection characteristics similar to foam mattresses. This geometric parameter modification provides progressive support comfort while maintaining the durability and reliability of metal spring construction.
3Ease of operation
If the pitch between convolutions is varied in different sections of the coil spring, then a non-linear loading response is achieved, but the device complexity increases
Solution Approach 1:
The coil spring is divided into distinct sections along its length, with each section having a characteristic pitch value. The first section has a first pitch and the second section has a second pitch, creating segmented zones with different mechanical properties. This segmentation approach achieves non-linear loading response by combining simple repetitive patterns in each section, rather than requiring continuous complex variations throughout the entire spring.
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 coil springs provide a user with the non-linear support of foam mattresses while maintaining durability and reducing production costs, as they maintain a consistent feel and support without mechanical degradation.
Implementation Method 1
the spring exhibits a linear compression rate. That is to say, it takes twice as much force to compress a typical spring two inches as it does to compress the same spring one inch. The linear response of springs is expressed by Hooke's law which states that the force (F) needed to extend or compress a spring by some distance (D) is proportional to that distance.
Data Source
AI summary
A spring is provided that exhibits a variable and non-linear loading response upon compression. The spring comprises a continuous wire having a lower end convolution, an upper end convolution, and a plurality of helical intermediate convolutions. The upper end convolution, the lower end convolution, and the helical intermediate convolutions each have a respective diameter, with the continuous wire further defining a pitch between the various convolutions. In the spring, one or more of the diameters of the convolutions or one or more of the pitches varies along the length of the continuous wire such that the spring exhibits a non-linear loading response upon compression. A mattress is further provided and includes a plurality of the springs arranged in a matrix.