Induction Heating System for Metal Food Cans with Power-Based Sterilization Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional methods for sterilizing food in metal containers, such as using steam in pressurized chambers, are inefficient and lack precise control over energy delivery, leading to suboptimal sterilization processes.

Innovation Solution

An induction heating system that uses an alternating magnetic field to heat hermetically sealed metal food cans, with temperature sensing and power monitoring elements to control and confirm the delivery of sufficient energy for sterilization, ensuring the food reaches and maintains a predetermined temperature for a specific duration.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If conventional steam heating in pressurized chambers is used, then sterilization can be achieved, but energy efficiency is poor and control precision is low

Engineering Contradiction:

Improveenergy efficiencyVSAvoidcontrol precision

Core Design Contradiction:

Loss of energyVSMeasurement precision

Solution Approach 1:

The patent replaces the conventional steam-based mechanical heating system with an induction heating system that uses electromagnetic fields to directly heat the metal container. This substitution eliminates the inefficiencies of steam transfer and provides precise control through electronic regulation of the induction coil power, directly addressing both energy efficiency and control precision concerns.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent implements a feedback control system using temperature sensors (such as thermocouples or RTDs) positioned within the container to monitor the actual temperature of the contents. This temperature data is fed back to a controller that adjusts the induction heating power in real-time, ensuring precise temperature control and verifying that sterilization parameters are met, thereby resolving the control precision issue.

Inventive Principle:

Principle #23Feedback

2Productivity

If steam heating is used, then sterilization can be achieved, but processing time is excessive

Engineering Contradiction:

Improveprocessing timeVSAvoidsterilization effectiveness

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The induction heating system uses electromagnetic induction to generate eddy currents directly in the metal container, which rapidly converts to heat through resistive heating. This direct heating mechanism is significantly faster than conventional steam heating, reducing processing time while maintaining sterilization effectiveness through precise temperature and time control via the feedback system.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent applies parameter changes by using high-frequency alternating current in the induction coil to generate intense electromagnetic fields that induce rapid heating in the container. By controlling frequency, power level, and heating duration through the feedback system, the process achieves rapid sterilization in a controlled manner, simultaneously improving productivity and maintaining reliability.

Inventive Principle:

Principle #35Parameter changes

3Loss of energy

If induction heating is used, then energy efficiency improves, but system complexity increases

Engineering Contradiction:

Improveenergy efficiencyVSAvoidsystem complexity

Core Design Contradiction:

Loss of energyVSDevice complexity

Solution Approach 1:

While the induction heating system introduces electromagnetic components, it eliminates the complexity of steam generation equipment, pressurized chamber systems, and steam distribution networks. The induction system with its coil, power supply, and temperature feedback creates a more compact and controllable system that achieves better energy efficiency despite the electronic control requirements.

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 method ensures effective sterilization of food in metal cans by precisely controlling the energy delivery, ensuring microbial lethality and rendering the food shelf-stable, while reducing energy consumption and processing time.

Implementation Method 1

an induction heating coil generating an alternating magnetic field... The magnetic field causes resistive heating of the metal of the sealed metal can

Methodology Applied

Scientific EffectElectromagnetic induction: Electromagnetic Induction

Implementation Method 2

The magnetic field causes resistive heating of the metal of the sealed metal can

Methodology Applied

Scientific EffectResistive heating: Joule Heating

Data Source

PatentUS10278410B2Food container induction heating system having power based microbial lethality monitoring

Publication Date: 2019.05.07 SILGAN CONTAINERS LLC

AI summary

Induction heating systems for metal food cans configured to deliver sufficient heat into the can to sterilize the food within the can are provided. The heating system includes an induction coil and a control system. The control system is configured to monitor and control heating of sealed food cans during induction heating and to control and/or confirm various aspects of can heating during induction heating.