Belt With Elastic Insert For Waist Adaptation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing belts with fixed or elastic straps struggle to accommodate slight variations in the user's waistline due to weight fluctuations, leading to discomfort and aesthetic issues, while elastic belts with conventional seams fail to provide sufficient tensile strength for supporting trousers.

Innovation Solution

A belt design featuring a strap made of non-elastically extendable material with an elastic insert fixed to one end, secured by a bar tack within the strap, and hidden by an oval-shaped cover, allowing the buckle to be removed with sufficient traction force to overcome the elastic insert's restoring force.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If an elastic strap is used to accommodate waistline variations, then adaptability is improved, but tensile strength deteriorates due to seam deterioration under body pressure

Engineering Contradiction:
Improveadaptability to waistline changesVSAvoidtensile strength
Core Design Contradiction:
Adaptability or versatilityVSStrength

Solution Approach 1:

The belt is divided into two distinct parts: a non-elastic strap portion that provides structural strength and an elastic insert portion that provides adaptability. The strap is made of rigid material (leather, synthetic leather, or fabric) while the insert is made of elastic material, allowing each component to fulfill its specific function without compromising the other.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The belt combines materials with different mechanical properties - a non-elastic strap material for strength and an elastic insert material for adaptability. This composite structure allows the belt to simultaneously achieve high tensile strength and elasticity, resolving the contradiction between strength and adaptability.

Inventive Principle:
Principle #40Composite materials

2Ease of manufacture

If the elastic insert is sewn using ordinary seams, then ease of manufacture is improved, but reliability deteriorates as seams break under weight greater than 10Kg

Engineering Contradiction:
Improveease of sewingVSAvoidseam durability
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The sewing parameters are specifically optimized for elastic materials. The patent specifies using a stretch stitch pattern, appropriate thread type (polyester or nylon), and adjusted stitch length (3-5mm) to accommodate the elastic properties of the insert material while maintaining seam strength under load.

Inventive Principle:
Principle #35Parameter changes

3Ease of manufacture

If the elastic insert is made visible, then ease of manufacture is improved, but aesthetic appearance deteriorates

Engineering Contradiction:
Improvemanufacturing simplicityVSAvoidaesthetic appearance
Core Design Contradiction:
Ease of manufactureVSShape

Solution Approach 1:

The belt displays different properties in different regions: the main strap portion has a uniform, aesthetically pleasing appearance, while the insert portion is strategically positioned and concealed within the strap structure. The insert is placed inside the strap fold or under the buckle, making it functionally visible only when needed for adjustment.

Inventive Principle:
Principle #3Local quality

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 design ensures the belt adapts to waistline changes while maintaining appearance and withstands significant weight without seam deterioration, providing enhanced tensile strength and comfort.

Implementation Method 1

a first portion (2) of the belt strap extending from the tip towards the waistline, said first portion being made of a material that substantially it is not elastically extensible... an elastic insert (9) made of an elastic material

Methodology Applied
Scientific EffectElastic deformation: Elasticity

Implementation Method 2

said opposite ends being sewn with a bar tack (12) to the first portion (2) of the belt strap, inside the first portion

Methodology Applied
Scientific EffectMechanical fastening: Mechanical Fastener

Data Source

PatentEP3998891B1A belt with an elastic insert for holding a buckle and a related manufacturing method
Publication Date: 2026.01.07 DANKE PELLETTERIA SRL
  • EP3998891B1 patent drawingFigure 1~2
  • EP3998891B1 patent drawingFigure 3~4
  • EP3998891B1 patent drawingFigure 5a~5b

AI summary

This disclosure shows a belt with a strap made of material which is substantially not elastically extendable. However, the belt adapts itself elastically to changes in the user's waist while maintaining the external appearance of the belts with a strap made of non- extendable material, because it has an elastic insert made of an elastic material, for example in polyester, folded on itself and fixed to an end of the strap in a longitudinally opposite position to a tip of the strap of the belt, and a buckle. The elastic insert is fixed to the strap so as to retain an anchoring bar of the buckle, so that the buckle can be removed longitudinally from the stem with a traction force that overcomes the restoring force of the elastic insert. A method of manufacturing such a belt with an elastic insert, for example in polyester, is also disclosed.