Four-Roller Rewinding Machine for Web Material Logs

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Solution Overview

Problem

Existing automatic continuous peripheral rewinding machines for producing logs of web material, such as toilet tissue or kitchen towels, face challenges in ensuring consistent operation and reproducibility, particularly due to variations in material properties and winding core sizes, which affect the accuracy and reliability of the winding cycle.

Innovation Solution

A rewinding machine with four rollers, including a first, second, third, and fourth winding roller, where the third roller is positioned upstream of the nip and the fourth downstream, allowing for continuous web material feeding and a severing mechanism to pinch the web material against the first roller, generating tension beyond its breaking point to efficiently sever the material, ensuring consistent winding cycles and handling of small diameter cores.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a traditional three-roller winding configuration is used, then the machine structure is simpler, but the winding accuracy and reliability deteriorate due to inability to maintain consistent operation with material property variations

Engineering Contradiction:
Improvewinding cycle reliabilityVSAvoidnumber of winding rollers
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The winding process is segmented into two distinct zones: a first winding cradle (rollers 1, 3, 7) for initial log formation and a second winding cradle (rollers 1, 3, 8) for completing the winding cycle. This segmentation allows each zone to be optimized for specific functions, improving overall reliability while managing complexity through functional division.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The third winding roller (7) acts as an intermediary element that facilitates the transition of the log being formed from the first winding cradle through the nip to the second winding cradle. This intermediary roller ensures consistent operation and maintains winding accuracy by providing additional support during the critical transition phase.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Manufacturing precision

If the web material is severed by lengthening the path between winding rollers, then the severing mechanism is simpler, but the winding accuracy and reproducibility deteriorate due to dependence on material properties

Engineering Contradiction:
Improvewinding accuracyVSAvoidsevering mechanism complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The traditional mechanical severing method (lengthening the web path) is replaced with a controlled differential speed mechanism. The winding rollers accelerate and decelerate in synchronism to create speed differences that cause the web material to tear at the desired location, providing precise control over severing timing and position.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The severing process is implemented through periodic acceleration and deceleration of the winding rollers. The rollers accelerate during the winding phase and decelerate in synchronism to create the speed differential needed for severing, repeating this cyclic action for each log production cycle with consistent timing and precision.

Inventive Principle:
Principle #19Periodic action

3Reliability

If the winding rollers rotate at controlled speed with acceleration and deceleration, then the log movement control is improved, but the energy consumption increases

Engineering Contradiction:
Improvelog movement controlVSAvoidwinding roller energy consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The winding rollers operate with periodic acceleration and deceleration cycles that are synchronized to the winding and severing operations. Energy is consumed primarily during acceleration phases, while deceleration phases utilize regenerative braking or coasting, reducing overall energy consumption while maintaining precise log movement control.

Inventive Principle:
Principle #19Periodic action

Solution Approach 2:

The winding rollers are equipped with speed control mechanisms that monitor and adjust rotation speeds in real-time. Feedback from sensors detects the position and state of the log, allowing the control system to optimize acceleration and deceleration profiles, minimizing energy consumption while ensuring reliable log movement and positioning.

Inventive Principle:
Principle #23Feedback

4Adaptability or versatility

If small diameter cores are processed, then the machine versatility is improved, but the difficulty of detecting and measuring increases

Engineering Contradiction:
Improvecore size handling capabilityVSAvoidsmall core detection difficulty
Core Design Contradiction:
Adaptability or versatilityVSDifficulty of detecting and measuring

Solution Approach 1:

The four-roller winding configuration with adjustable nip width and synchronized speed control creates a universal system capable of handling multiple core diameters. The same basic mechanism adapts to different core sizes by adjusting roller positions and speed profiles, eliminating the need for dedicated systems for different core dimensions.

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

Solution Approach 2:

Traditional mechanical detection methods for small cores are replaced with non-contact sensing technologies. Optical sensors or other detection systems monitor the position and dimensions of small diameter cores without physical contact, eliminating measurement difficulties associated with mechanical probes and improving detection accuracy for minimal core sizes.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

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

This configuration enables continuous and efficient production of logs with improved winding accuracy and reliability, maintaining constant web material feed speed independent of the winding cycle, and effectively processing small diameter cores without interrupting the material flow.

Implementation Method 1

a severing mechanism configured and controlled to pinch the web material against the first winding roller and sever the web material by generating in the web material a tension greater than the breaking point of the web material

Methodology Applied
Scientific EffectTension: Tension

Data Source

PatentEP3174819B1Rewinding machine and method for producing logs of web material
Publication Date: 2019.06.05 FABIO PERINI SPA
  • EP3174819B1 patent drawingFigure 1
  • EP3174819B1 patent drawingFigure 2
  • EP3174819B1 patent drawingFigure 3

AI summary

The rewinding machine comprises a first winding cradle formed be- tween a first winding roller (1), a second winding roller (3) and a third winding roller (7). The first winding roller and the second winding roller define a nip (5) through which there pass the winding cores (A) with the web material (N) being wound around them;The rewinding machine also comprises a feed path of the winding cores that pass between the first winding roller (1) and the third winding roller (7). A second winding cradle is formed between the first winding roller (1), the second winding roller (3) and a fourth winding roller (8). The rewinding ma- chine also comprises a rolling surface (19) extending around the first winding roller (1) and defining a feed channel (21) of the winding cores.