Interchangeable Inserts for Tyre Forming Drum Wear

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing forming drums used in tyre production are not well adapted to sustain high mechanical stresses, leading to early wear and breakage, and require multiple drums for different tyre sizes, causing logistical and cost issues.

Innovation Solution

The use of axially opposite auxiliary elements or inserts that form continuous annular surfaces on the forming drum, allowing for easier component application, increased structural strength, and easy adaptation to different tyre sizes and geometries, reducing the need for multiple drums and associated costs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If conventional forming drums are used without auxiliary elements, then the drum structure is simple, but the drum cannot sustain high mechanical stresses and suffers early wear and breakage

Engineering Contradiction:
Improvestructural strengthVSAvoiddrum structure complexity
Core Design Contradiction:
StrengthVSDevice complexity

Solution Approach 1:

The forming drum is divided into sectors with interchangeable auxiliary elements that can be independently replaced. This segmentation allows the drum to maintain high structural strength through reinforced auxiliary elements while keeping the overall device complexity manageable by only modifying specific segments rather than the entire drum structure.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The auxiliary elements are made of material with higher mechanical strength properties compared to the base drum structure. This composite approach combines the simplicity of the base drum with the high strength of auxiliary elements, resolving the contradiction between structural strength and device complexity.

Inventive Principle:
Principle #40Composite materials

2Adaptability or versatility

If multiple forming drums are used for different tyre sizes, then adaptability to different tyre sizes is improved, but logistical complexity and costs increase

Engineering Contradiction:
Improveadaptability to different tyre sizesVSAvoidlogistical complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

A single forming drum is designed with interchangeable auxiliary elements that can be configured for different tyre sizes and geometries. This universal drum replaces multiple specialized drums, improving adaptability while reducing logistical complexity by eliminating the need to manage, store, and maintain multiple different drum units.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The forming drum system becomes dynamic and reconfigurable through the interchangeability of auxiliary elements. Instead of static drums designed for specific tyre sizes, the system can adapt its configuration by swapping auxiliary elements, enabling one drum to serve multiple functions across different tyre specifications.

Inventive Principle:
Principle #15Dynamics

3Ease of operation

If conventional forming drums without continuous annular surfaces are used, then the drum structure is simpler, but component application becomes difficult and axial thrusts are not effectively sustained

Engineering Contradiction:
Improvecomponent application easeVSAvoiddrum surface complexity
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

Continuous annular surfaces are introduced at specific local positions on the drum where auxiliary elements are mounted, rather than making the entire drum surface complex. This localized approach improves component application ease at critical areas while maintaining relative simplicity elsewhere in the drum structure.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The continuous annular surfaces act as intermediary elements between the drum and the tyre components being formed. These surfaces facilitate smooth component application and distribution of axial thrusts, improving ease of operation without requiring fundamental changes to the entire drum structure.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP4196342B1Process and apparatus for building tyres
Publication Date: 2024.10.23 PIRELLI TYRE SPA
  • EP4196342B1 patent drawingFigure 1
  • EP4196342B1 patent drawingFigure 2
  • EP4196342B1 patent drawingFigure 3

AI summary

A forming drum (14) is arranged, comprising radially movable, circumferentially consecutive sectors (16), each comprising a central body (18) and a pair of interchangeable inserts (23), each engaged with an axial end edge (19) of the central body (18). The forming drum (14) is brought to an expanded condition in which the sectors (16) are radially moved away from said geometric axis (X-X) in order to define a radially outer deposition surface (S) on which components of a first tyre (2) being processed are applied. During the expansion of the forming drum (14), the inserts (23) of each sector (16) are moved with respect to the respective central bodies (18) up to an operative position in which said inserts (23) extend, each on the continuation of the inserts (23) belonging to the circumferentially adjacent sectors (16), in order to form essentially continuous annular elements (31) extending along the axially opposite edges (20) of the forming drum (14).