Segmented Thermoforming Mold Shell for Film Thickness Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing deep-drawing tools for packaging machines face issues with film thickness variations during the deep-drawing process, leading to potential tearing and low dimensional stability, as the film thickness can fall below critical values, especially in the lowermost areas of the packaging tray.

Innovation Solution

The deep-drawing tool features a mold shell with multiple segments that can move independently and be heated or cooled, allowing for controlled deformation and material flow, with a reversible adhesive to maintain contact with the film, preventing excessive thinning and ensuring consistent thickness by adjusting the movement of segments relative to the frame and each other.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If a deep-drawing tool with a fixed mold shell is used, then the structure is simple and easy to manufacture, but the film thickness varies significantly during deep-drawing, falling below critical values in lower areas

Engineering Contradiction:
Improvefilm thickness consistencyVSAvoidmold shell structure
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The mold shell is divided into multiple segments that can move independently relative to each other and the frame. This segmentation allows different areas of the mold to be positioned at different times during deep-drawing, enabling controlled deformation and material flow to maintain consistent film thickness throughout the packaging tray.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The mold shell segments are made movable rather than fixed, allowing dynamic adjustment during the deep-drawing process. The segments can be moved towards the film or pick it up in its planar starting position, and their movement can follow, lead, or lag behind the film deformation to control material flow and prevent excessive thinning.

Inventive Principle:
Principle #15Dynamics

2Manufacturing precision

If the mold shell is made movable to control film deformation, then film thickness consistency is improved, but the device complexity and difficulty of operation increase

Engineering Contradiction:
Improvefilm thickness consistencyVSAvoidmold operation complexity
Core Design Contradiction:
Manufacturing precisionVSEase of operation

Solution Approach 1:

By dividing the mold shell into manageable segments with independent drives, the complexity of controlling the entire mold is reduced. Each segment can be operated independently or in coordination with others, allowing for simplified control strategies while achieving precise film thickness management.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The reversible adhesive on the mold segments automatically maintains contact with the film during deformation without requiring complex external control systems. The adhesive naturally adjusts to the film's movement, reducing the operational complexity while maintaining precision.

Inventive Principle:
Principle #25Self-service

3Manufacturing precision

If the shell mold segments are moved towards the film during deep-drawing, then material flow is controlled and thickness consistency is improved, but the device complexity increases

Engineering Contradiction:
Improvematerial flow controlVSAvoidsegment drive system
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The dynamic movement of segments towards the film during deep-drawing allows precise control of material flow. By timing the segment movement to follow, lead, or lag behind the film deformation, the system optimizes material distribution and prevents excessive thinning while managing the complexity through coordinated motion control.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The segment drives allow adjustment of movement parameters such as timing, speed, and distance. By optimizing these parameters, the system achieves effective material flow control and thickness consistency while minimizing the complexity of the drive system itself.

Inventive Principle:
Principle #35Parameter changes

4Productivity

If negative pressure is applied between the mold and film during deep-drawing, then the film deforms effectively, but the film thickness falls below critical values in heavily deformed areas

Engineering Contradiction:
Improvedeep-drawing efficiencyVSAvoidminimum film thickness
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

Dividing the mold into segments allows different areas to be deformed at different times and rates. This prevents simultaneous excessive deformation across the entire film, maintaining minimum thickness requirements while still achieving effective overall deformation and high productivity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The dynamic movement of segments during negative pressure application allows the mold to adapt to the film's deformation progress. By moving segments to follow or lead the film deformation, the system maintains control over material flow and prevents critical thinning while preserving deep-drawing efficiency.

Inventive Principle:
Principle #15Dynamics

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 solution ensures that the film maintains a stable thickness throughout the deep-drawing process, preventing tears and ensuring dimensional stability by controlling the film's deformation and material flow, allowing for efficient production of packaging trays with consistent quality.

Implementation Method 1

The deep-drawing tool features a mold shell with multiple segments that can move independently and be heated or cooled

Methodology Applied
Scientific EffectHeating: Heating

Implementation Method 2

The deep-drawing tool features a mold shell with multiple segments that can move independently and be heated or cooled

Methodology Applied
Scientific EffectCooling: Cooling

Implementation Method 3

with a reversible adhesive to maintain contact with the film

Methodology Applied
Scientific EffectAdhesive: Adhesive

Data Source

PatentEP3390234B1Mold comprising a split mold shell
Publication Date: 2020.04.15 GEA FOOD SOLUTIONS GERMANY GMBH
  • EP3390234B1 patent drawingFigure 1~4

AI summary

The invention relates to a thermoforming mold for a packaging machine for manufacturing a packaging tray by thermoforming a film web, comprising at least one mold shell and a frame. The present invention further relates to a packaging machine comprising the disclosed mold as well as to a method for thermoforming a packaging tray.