Radially Expandable Tire Processing Head for Adhesion

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current tire production processes face challenges in applying semi-finished products, such as self-sealing sleeves, due to differences in tire sizes and bead diameters, which hinder easy insertion and adhesion to the radially inner surface, leading to potential air bubbles and defects.

Innovation Solution

A device with a processing head and movement group that radially expands and presses the semi-finished product against the tire's inner surface, using a pressing element to facilitate adhesion and expel air, allowing for flexible application on green or vulcanized tires.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a semi-finished product is inserted into a tyre, then the self-sealing function is achieved, but air bubbles and adhesion defects occur due to tire size and bead diameter variations

Engineering Contradiction:
Improveself-sealing functionVSAvoidadhesion quality
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The pressing element is made radially movable relative to the processing head, allowing it to dynamically adjust its position and apply varying pressure to the semi-finished product during rotation. This dynamic adjustment ensures consistent adhesion quality across different tire sizes and bead diameters, preventing air bubbles and defects while maintaining reliable self-sealing function.

Inventive Principle:
Principle #15Dynamics

2Manufacturing precision

If the pressing element applies high pressure to ensure adhesion, then manufacturing precision improves, but device complexity increases due to radial movement mechanism

Engineering Contradiction:
Improveadhesion qualityVSAvoidpressing element mechanism
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The pressing element utilizes the natural curvature and rotation of the processing head to achieve radial movement. The rotating processing head itself provides the mechanical advantage needed to press the semi-finished product against the tire inner surface, eliminating the need for complex additional actuation mechanisms while maintaining high adhesion quality.

Inventive Principle:
Principle #14Spheroidality (Curvature)

3Productivity

If the processing head rotates at high speed to increase productivity, then production rate improves, but adhesion quality deteriorates due to reduced pressing time

Engineering Contradiction:
Improveproduction rateVSAvoidadhesion quality
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The semi-finished product is pre-positioned on the processing head before rotation begins. This preliminary positioning ensures that the product is already in the correct location and orientation, allowing the system to rotate at high speeds without compromising adhesion quality, as the pressing action is maintained throughout the rotation cycle.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP3727824B1Device for applying semi-finished products inside tyres for vehicle wheels
Publication Date: 2023.05.10 PIRELLI TYRE SPA
  • EP3727824B1 patent drawingFigure 1
  • EP3727824B1 patent drawingFigure 2
  • EP3727824B1 patent drawingFigure 3~4

AI summary

A processing head (14) is provided that is axially insertable in the tyre (3) retained by a support group (15). The processing head (14) comprises at least one or more radially extendable arms (20), having each a proximal end (20a) that is constrained with respect to the processing head (14) and a distal end (20b) carrying at least one pressing element (21). Driving devices (22) operate on each arm (20) in order to move it between a rest position in which the pressing element (21) is moved close to the geometric rotation axis (X) and a work position in which the pressing element (21) is moved away from the geometric rotation axis (X) in order to exert a thrust action towards a radially inner surface (3a) of the tyre (3). A movement group (16) provides for mutually moving the processing head (14) and the tyre (3) around and along a geometric rotation axis (X), in order to complete the application of a semi-finished product (2) by the pressing elements (21).