Dynamic Vacuum Decay Leak Detection for Low Headspace Packaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional vacuum decay methods for testing package integrity are unreliable in detecting leaks in low headspace packaging, as they may evacuate all air before a leak can be detected, leading to false negatives or undetected large leaks.
Innovation Solution
A dynamic vacuum decay control system that uses a timer in conjunction with pressure feedback to control the vacuum level in the test chamber, allowing for delayed isolation from the vacuum source based on detected pressure levels, ensuring accurate leak detection in both low and high headspace containers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stress or pressure
If vacuum is pulled until target vacuum level is reached, then vacuum level is improved, but large leaks may bleed all air out during evacuation cycle and defect goes undetected
Solution Approach 1:
The system performs preliminary action by initiating a timer when trigger pressure is detected during evacuation, before the target vacuum level is reached. This timing mechanism ensures that the isolation valve closes at the predetermined time regardless of whether target vacuum is achieved, preventing complete air evacuation and ensuring leak detection capability is maintained.
Solution Approach 2:
The system uses feedback by continuously monitoring pressure during evacuation and detecting trigger pressure to initiate the timer. This feedback mechanism allows the system to adapt the isolation timing based on actual pressure conditions, ensuring reliable leak detection while maintaining appropriate vacuum levels.
2Productivity
If timer-based vacuum pulling is used, then test speed is improved, but package requiring more time to evacuate may not reach vacuum and may be falsely detected as leak
Solution Approach 1:
The system applies dynamics by making the isolation timing dynamic rather than fixed. The timer is initiated based on detected trigger pressure during evacuation, allowing the system to adapt to different package evacuation rates. This dynamic timing ensures that packages requiring more time to evacuate are not falsely detected as leaks, while maintaining test speed through automated control.
3Stress or pressure
If vacuum evacuation continues until target level, then vacuum quality is improved, but large leaks leak air out during evacuation and slow down evacuation process
Solution Approach 1:
The system performs preliminary action by closing the isolation valve at a predetermined time after trigger pressure detection, before complete vacuum is achieved. This preliminary isolation prevents large leaks from continuing to bleed air during extended evacuation, maintaining evacuation speed while ensuring sufficient vacuum quality for leak detection.
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 effectively detects even sub-visible leaks in various containers by dynamically controlling vacuum decay, minimizing incorrect test results and ensuring reliable detection of leaks in containers with low or high headspace volumes.
Implementation Method 1
a vacuum is pulled within the system plus the chamber by a vacuum pump
Implementation Method 2
pressure feedback control system, such that isolation of the test chamber from the vacuum source is delayed based upon detection of a predetermined pressure level
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
A method and system of testing for package leaks by a test system is disclosed. The test system includes a vacuum source and a test chamber in which a package is received for testing. A package is placed in the test chamber, and a vacuum is drawn on the test chamber by the vacuum source. A predetermined pressure level in the test system is detected, and based upon the detection of the predetermined pressure level, the test system determines when to stop drawing the vacuum. The test chamber is isolated from the vacuum source based upon the determination, and subsequently the test system detects the presence or absence of a leak in the package based on pressure measurements in the test chamber. A timer may be used to determine the delay in isolating the test chamber from the vacuum source after detection of the predetermined pressure level.