Plastic Container Thermal Inspection for Quality and Energy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for inspecting plastic containers manufactured by molding are either destructive, restrictive, or fail to guarantee quality, leading to nonconformal containers being accepted and potentially causing defects in packaging and brand image issues, while also consuming significant energy due to high blowing pressures.
Innovation Solution
A nondestructive method involving thermal imaging to capture and characterize containers post-molding, focusing on critical zones with a predetermined temperature threshold to assess quality and mechanical strength, reducing inspection time and energy consumption by optimizing blowing pressures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If sampling-based inspection method is used, then minimal thickness can be checked, but the container becomes unusable and quality guarantee is insufficient
Solution Approach 1:
The patent uses thermal imaging to create a visual copy of the container's wall thickness distribution without physical contact. The thermal image captures temperature variations that correspond to thickness variations, allowing inspection without destroying the container. This resolves the contradiction by enabling non-destructive measurement while improving quality guarantee through comprehensive inspection.
Solution Approach 2:
The patent replaces mechanical cutting and physical measurement with thermal imaging technology. Instead of physically cutting containers to measure thickness, the system uses thermal cameras to detect temperature differences caused by varying wall thicknesses, substituting mechanical inspection with optical/thermal detection to maintain container usability while improving inspection reliability.
2Measurement precision
If wall thickness measurement method is used, then minimal thickness can be confirmed, but geometric forms such as grooves, feet or bosses cannot be inspected
Solution Approach 1:
The thermal imaging system serves multiple inspection functions simultaneously. It can detect both wall thickness variations and geometric form defects (grooves, feet, bosses) by analyzing temperature distribution patterns across the entire container surface. This multi-functional approach resolves the contradiction by providing comprehensive inspection capability through a single method.
Solution Approach 2:
The patent transitions from one-dimensional thickness measurement to two-dimensional surface temperature mapping. By capturing thermal images across the entire container surface, the system can identify both thickness variations and geometric form defects, adding spatial dimensionality to the inspection process and enabling comprehensive quality assessment.
3Strength
If high blowing pressures are used, then container strength is ensured, but energy consumption increases significantly
Solution Approach 1:
The thermal imaging system provides real-time feedback on container wall thickness and geometric form quality during or after the blowing process. This feedback enables optimization of blowing pressure parameters to achieve the minimum necessary pressure for quality containers, avoiding excessive energy consumption while maintaining strength requirements.
Solution Approach 2:
The patent enables optimization of manufacturing parameters including blowing pressure based on thermal imaging results. By adjusting blowing pressure parameters according to detected thickness and form variations, the system can reduce energy consumption while maintaining container strength, resolving the contradiction between these two parameters.
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 higher quality inspections, reduces energy consumption, and allows for real-time feedback on manufacturing parameters and mold geometry, minimizing the risk of accepting defective containers and improving production efficiency.
Implementation Method 1
a step of capturing a thermal image of the container on leaving the mold
Implementation Method 2
preforms heated to a glass transition temperature at which the plastic material is softened and easily deformed
Data Source
AI summary
The invention relates to a method for inspecting a container (2) made of plastic material obtained by molding, the method comprising:a step of capturing a thermal image of the container (2) on leaving the mold (31);a step of characterization of the container (2), in which a rule for acceptance or rejection of the quality of the container (2) is applied, as a function of the thermal image of the container (2) on leaving the mold (31),wherein, prior to the characterization step, the method comprises a step of identification, on the thermal image, of at least critical zone corresponding to a structural part of the container (2),and wherein the acceptance rule is parameterized to consider a container (2) as acceptable if, for each identified critical zone, the temperature of the container is lower than a predetermined threshold temperature.