Shipping Container Positive Locking Tab Pressure Seal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional corrugated paperboard shipping containers that rely solely on friction between tabs and slots for structure are neither tamper-resistant nor tamper-evident, as they can be easily compromised by removing and reinserting tabs without altering their appearance.
Innovation Solution
A shipping container design that incorporates a positive locking tab with a length greater than the slot, featuring a notch and angled score lines to secure the lid through pressure, ensuring the container holds its shape without fasteners and provides tamper-resistance and evidence of tampering.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a container is constructed by relying on slot/tab friction to hold its shape, then the container can be assembled without fasteners, but the container is neither tamper-resistant nor tamper-evident
Solution Approach 1:
The patent changes the engagement parameter from friction-based to pressure-based. The locking tab is designed with a length greater than the slot length, creating an interference fit that engages through pressure rather than friction. This allows the container to be assembled without fasteners while providing tamper-resistance, as the pressure-based engagement cannot be easily disengaged and re-engaged without detection.
2Device complexity
If a container uses friction between slots and tabs to hold its shape, then the container structure is simple, but the container allows easy tampering with undetectable appearance changes
Solution Approach 1:
The patent introduces a curved engagement surface between the locking tab and slot. The locking tab has a curved surface that engages with a corresponding curved slot, creating a pressure-based interference fit. This curved geometry provides tamper-resistance while maintaining relatively simple container structure, as the curved surfaces naturally distribute pressure and prevent easy disengagement.
3Reliability
If a positive locking tab with length greater than slot is used, then the container becomes tamper-resistant, but the manufacturing precision requirements increase
Solution Approach 1:
The patent specifies that the locking tab length should be greater than the slot length by a specific amount (0.02 to 0.06 inches), creating an interference fit. This parameter change provides tamper-resistance while accommodating reasonable manufacturing tolerances. The interference fit ensures engagement through pressure rather than requiring extremely precise friction-based dimensions.
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 container is self-locking, tamper-resistant, and tamper-evident, allowing for secure closure and quick assembly without the need for fasteners, while maintaining a seamless appearance until opened, and can be reused after locking.
Implementation Method 1
The lid is locked using pressure, as opposed to friction. Unlike a positive locking tab as in the present disclosure, an arrangement using friction between a tab and a slot is not made stronger by pressure.
Data Source
AI summary
A shipping container has a lid locked using pressure, rather than friction. The container includes front and rear side panels and a lid. The lid has a positive locking tab for engaging with a slot in the front side panel. The tab has a greater length than the slot. An end of the tab and an edge of the lid form a notch therebetween. In an embodiment, a corrugated paperboard blank is folded to approximate the lid to the front side panel. The lid is folded along an angled score line, rotating the tab with respect to the slot so that an end of the tab engages the slot and the front panel at an end of the slot engages the notch. The lid is folded to rotate the tab in the opposite direction; the tab then engages with the slot, the end of the tab extending beyond the slot.