Induction Sealing Device with Magnetic Insert

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing induction sealing devices for packaging materials are prone to cracking due to mechanical loads, have integrity issues during sealing, and are costly due to complex manufacturing and expensive materials, while also failing to meet quality requirements, especially when sealing over fin creases and stops.

Innovation Solution

A simplified induction sealing device design featuring a supporting body with cavities for moulding a flux-concentrating insert directly, eliminating the need for additional plastic parts and using a magnetic compound with soft magnetic particles and a fiber structure for enhanced mechanical strength, along with a stainless steel supporting body for improved robustness and thermal conductivity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a plastic supporting body with integrated inductor housing is used, then the device structure is simplified, but the device becomes susceptible to cracking under mechanical loads

Engineering Contradiction:
Improvestructure complexityVSAvoidmechanical strength
Core Design Contradiction:
Device complexityVSStrength

Solution Approach 1:

The patent applies composite materials by combining a metal supporting body (stainless steel or aluminum) with a magnetic insert (ferrite or other magnetic material). This composite structure provides both the mechanical strength needed to withstand packaging line loads and the magnetic properties required for induction sealing functionality. The metal supporting body replaces the previously used plastic material, eliminating cracking issues while maintaining structural integration.

Inventive Principle:
Principle #40Composite materials

2Reliability

If additional plastic parts and secondary moulds are used to house the inductor device, then the sealing function can be performed, but the manufacturing cost increases and the device becomes more complex

Engineering Contradiction:
Improvesealing functionVSAvoidmanufacturing cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent merges multiple functions into a single supporting body component. The metal supporting body simultaneously serves as the structural housing, the inductor mounting platform, and the sealing jaw assembly support. This eliminates the need for separate plastic supporting bodies and secondary mould parts, reducing manufacturing steps and costs while maintaining reliable sealing functionality.

Inventive Principle:
Principle #5Merging (Combining)

3Ease of manufacture

If a plastic supporting body is used, then the initial manufacturing is easier, but the working life is reduced due to cracking

Engineering Contradiction:
Improveinitial manufacturingVSAvoidworking life
Core Design Contradiction:
Ease of manufactureVSDuration of action of stationary object

Solution Approach 1:

The metal supporting body (stainless steel or aluminum) provides superior mechanical strength and durability compared to plastic materials. While metal requires different manufacturing processes, it eliminates the cracking issue that limited the working life of plastic supporting bodies. The magnetic insert is securely mounted within the metal structure, ensuring long-term reliability in high-speed packaging environments.

Inventive Principle:
Principle #40Composite materials

4Device complexity

If conventional heat sealing is used, then the sealing process is simple, but sealing quality over fin creases and stops is insufficient

Engineering Contradiction:
Improvesealing process complexityVSAvoidsealing quality
Core Design Contradiction:
Device complexityVSManufacturing precision

Solution Approach 1:

The patent replaces conventional mechanical heat sealing with induction sealing technology. The inductor generates an electromagnetic field that induces eddy currents in the metallic layer of the packaging material, generating heat directly within the material itself. This eliminates the need for direct contact between the sealing jaw and the package, allowing consistent sealing quality over fin creases, stops, and irregular surfaces that cannot be achieved with mechanical pressure alone.

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

The solution results in a more robust, cost-effective, and longer-lasting induction sealing device that maintains or improves sealing quality and reduces the risk of mechanical failure, while simplifying manufacturing and eliminating the need for secondary mould parts.

Implementation Method 1

loss current is induced in, and locally heats, the aluminium sheet

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Implementation Method 2

in induction heat sealing, the heating means substantially comprise an inductor powered by a high-frequency current generator and substantially comprising one or more inductor bars made of electrically conductive material, extending parallel to the second direction, and which interact with the tube material to induce a loss current in it and heat it to the necessary sealing temperature

Methodology Applied
Scientific EffectInduction heating: Induction Heating

Implementation Method 3

an insert made of magnetic flux-concentrating material - in particular, a composite material comprising ferrite - and housed inside the supporting body, close to the inductor bars

Methodology Applied
Scientific EffectMagnetic flux concentration: Magnetic Field

Data Source

PatentEP3224020B1Simplified transversal induction sealing device
Publication Date: 2020.01.29 TETRA LAVAL HOLDINGS & FINANCE SA
  • EP3224020B1 patent drawingFigure 1~2
  • EP3224020B1 patent drawingFigure 3~4a
  • EP3224020B1 patent drawingFigure 4b~4c

AI summary

Disclosed embodiments relate to an induction sealing device for heat sealing packaging material for producing sealed packages of pourable food products. In some embodiments, the sealing device includes: an inductor device which interacts with said packaging material by means of at least one active surface; a flux-concentrating insert; and a supporting body made of heat-conducting material and housing said inductor device and said flux-concentrating insert, wherein said flux concentrating insert is made by a magnetic compound of a polymer and soft magnetic particles; and said flux concentrating insert interacts with said packaging material via at least one interactive surface.