Tire Drum Lever Mechanism Sidewall Folding

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing drum technologies for producing vehicle tires face issues with sidewall strip folding, leading to potential bead core slippage and irregularities in the tire's thickness, resulting in uneven tread surfaces and impaired running behavior.

Innovation Solution

A drum with a clamping device and lever device featuring levers that exceed the length of center segments, allowing for complete folding of sidewall strips over the entire length, along with guide elements for uniform guidance, and adjustable center segments for varying tire widths, ensuring stable bead core positioning and material layer application.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the sidewall strip is folded over only partially (not covering the entire center segment length), then the folding process is simpler and faster, but the bead core becomes loose or slips and the tire surface becomes uneven

Engineering Contradiction:
Improvefolding process efficiencyVSAvoidbead core positioning stability
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent applies local quality by making the lever length A' specifically greater than or equal to the center segment length A, creating a localized geometric relationship that enables complete sidewall strip folding. This local dimensional adjustment ensures the sidewall strip edge aligns with the center segment edge, preventing bead core slippage and surface unevenness while maintaining folding efficiency.

Inventive Principle:
Principle #3Local quality

2Manufacturing precision

If the lever length A' is increased to be greater than or equal to the center segment length A, then the sidewall strip can be folded over the entire length ensuring uniform tire thickness, but the device complexity increases

Engineering Contradiction:
Improvetire thickness uniformityVSAvoidlever device complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent applies segmentation by dividing the drum into center segments with axial length A, and designing the lever device with levers of length A' that correspond to these segments. This segmentation allows the sidewall strip to be folded uniformly over the entire center segment length, ensuring consistent tire thickness while keeping the lever device structurally organized and manageable.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent applies parameter changes by specifically setting the lever length A' to be greater than or equal to the center segment length A. This parameter adjustment is the key innovation that enables complete sidewall strip folding across the entire center segment, ensuring uniform tire thickness and proper bead core embedding without requiring complex additional mechanisms.

Inventive Principle:
Principle #35Parameter changes

3Manufacturing precision

If guide elements are added between the levers, then the sidewall strip folding becomes more uniform and precise, but the device complexity and manufacturing cost increase

Engineering Contradiction:
Improvesidewall strip folding precisionVSAvoidlever device structure complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent applies the intermediary principle by introducing guide elements between the levers of the lever device. These guide elements act as mediators that direct and control the sidewall strip during the folding process, ensuring uniform and precise folding across the entire center segment length while maintaining a relatively simple overall device structure.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP4034373B1Drum and method for producing vehicle tyres
Publication Date: 2024.11.13 HERBERT MASCH & ANLAGENBAU GMBH & CO KG
  • EP4034373B1 patent drawingFigure 1
  • EP4034373B1 patent drawingFigure 2a~3b
  • EP4034373B1 patent drawingFigure 4a~5b

AI summary

The invention relates to a drum and a method for producing vehicle tyres, in particular tyres for bicycles, motorcycles, scooters or the like, wherein the drum comprises a clamping device (11) with central segments (12) for holding a tyre carcass and comprises at least one turning-up device (13) for turning up a sidewall strip of the tyre carcass over a bead core of the tyre, wherein the turning-up device comprises a lever mechanism (15), wherein the lever mechanism has a plurality of levers (16), by means of which the sidewall strip can be turned up, wherein the central segments have an axial length A in the direction of a longitudinal axis (14) of the drum, wherein the levers have a length A', where the length A' of the levers is greater than or equal to the length A of the central segments.