Paper Lid Tapered Side Wall Seal
Solution Overview
Problem
Paper lids for beverage containers face challenges in achieving high sealability and preventing liquid leakage due to low elasticity and formability compared to plastic lids, and are prone to dimensional variations that affect fit and stability.
Innovation Solution
A paper lid design featuring a tapered side wall with an integrated cover wall and a standing part, an engaging part with a ring-shaped recess, and a lower end that is non-contact with the container's side wall, allowing for elastic engagement and high sealability despite dimensional variations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a paper lid is designed with conventional structures (overlapping side wall and cover wall), then the lid can be made from paper material, but the adhesion to the container opening is insufficient and liquid leakage occurs
Solution Approach 1:
The lid is divided into distinct functional parts: a side wall with a specific tapered shape and an engaging part at its lower end, and a cover wall. The side wall engages with the container opening while the cover wall provides closure, allowing each part to optimize its function independently.
Solution Approach 2:
The side wall is designed with a tapered shape that allows it to dynamically adapt to dimensional variations in the container opening. The gradual change in diameter from upper to lower end enables the lid to maintain reliable engagement despite moisture-induced dimensional changes in paper materials.
2Strength
If the side wall and cover wall are joined with overlapping structures, then structural strength is improved, but the fitting elasticity is reduced and dimensional variations cause poor sealability
Solution Approach 1:
The joining structure is localized to specific regions: the standing part at the circumference of the cover wall joins to the inner surface of the upper wall of the side wall, while the lower end of the side wall maintains its elasticity for engagement. This localized joining preserves flexibility where needed while providing structural strength where required.
3Reliability
If the engaging part contacts the container side wall, then adhesion is improved, but the lid becomes difficult to remove and stackability is reduced
Solution Approach 1:
The engaging part is designed to engage partially with the container opening without requiring full contact with the side wall. The tapered side wall provides sufficient engagement through its lower end while leaving the bottom surface free to avoid excessive adhesion, enabling easy removal and stacking.
Data Source
AI summary
A lid having an excellent sealability of an opening part of a container is for attaching to an opening part of a container in a removable manner, characterized in including a cover wall and a side wall which surrounds the circumference of the cover wall, which is tapered from an upper end towards an lower end and which is made of a paper material, wherein the cover wall and the side wall are integrated with each other by a standing part formed on the circumference of the cover wall being joined to an inner surface of an upper wall of the side wall, wherein an engaging part for engaging with the opening part of the container is provided on an inner circumferential side of a lower wall of the side wall.