Leathercraft Article Sandwich Structure Weight Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Leather goods articles, such as briefcases and laptop bags, often weigh excessively due to their rigid core and leather facings, compromising their self-supporting and non-deformable characteristics while being aesthetically biased.
Innovation Solution
A sandwich structure comprising two superimposed leather or leather substitute pieces fixed on either side of an elastically compressible cellular plastic core, with a notch-shaped hollow and secured edges, prevents displacement and maintains self-supporting and non-deformable properties while reducing weight.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a rigid core and leather facings are used to ensure self-supporting and non-deformable characteristics, then the structural integrity is improved, but the weight increases excessively (exceeding 1.5 kg for a simple briefcase)
Solution Approach 1:
The patent applies composite materials by combining a foam core with leather or synthetic leather facings. The foam core provides the necessary rigidity and self-supporting characteristics, while the thin facing layers contribute minimal weight. This composite structure achieves structural integrity without the excessive weight of traditional solid rigid materials, directly resolving the contradiction between strength and weight.
Solution Approach 2:
The patent uses thin facing layers (shell structure) made of leather or synthetic leather that cover the foam core. These thin films provide the aesthetic appearance and protective function while adding minimal weight. The foam core maintains the structural rigidity, creating a lightweight yet strong construction that solves the weight-integrity contradiction.
2Weight of moving object
If a sandwich structure with foam core and leather facings is used, then the weight is reduced, but the article becomes elastically deformable in flexion, torsion and compression
Solution Approach 1:
The patent modifies the parameters of the foam core, specifically its density and thickness, to optimize the balance between weight and rigidity. By carefully selecting the foam density and core thickness, the structure achieves sufficient rigidity to resist deformation under normal use conditions while maintaining lightweight characteristics. This parameter optimization resolves the contradiction between weight reduction and maintaining structural stability.
3Weight of moving object
If the core is made thinner to reduce weight, then the weight decreases, but the self-supporting nature and non-deformability are compromised
Solution Approach 1:
The patent uses the composite combination of foam core and facing layers where the foam provides internal structural support and the facing layers add surface rigidity. This composite action allows the core to be thinner while maintaining overall structural strength, as the facing layers contribute to the bending resistance and structural integrity, resolving the contradiction between thin core weight savings and structural strength.
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 achieves a lightweight yet self-supporting and aesthetically pleasing leather goods article, weighing less than 1.5 kg for a simple attaché case, while maintaining its structural integrity and visual appeal.
Implementation Method 1
an elastically compressible cellular plastic core
Implementation Method 2
fixed on either side of an interposed internal core by means of a fixing means such as glue
Data Source
Figure 1~2
Figure 3~3A
Figure 3B~4
AI summary
The invention concerns a leathercraft article such as an attaché-case, a pilot's briefcase, a laptop briefcase, luggage (1) or the like, self-carrying and substantially undeformable in normal use conditions, globally parallelepiped with two large flat surfaces (7, 8) and peripheral edges (9 12) adjacent to one another while forming ridges (13 20) and externally rounded corners (2124, 21' 24'), comprising a base (2) and a top (3) associated with the base (2) so as to be pivotable between a closed state where it is capable of being fixed thereto via fixing means and an open state, the base (2) and optionally the top (3) being shell-shaped, the base (2) and the top (3) being delimited each by a free peripheral edge.