Double-Walled Bottle Cap Cover With Snap-Lock Retention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing cap covers for bottles, particularly those with threaded necks like nail polish bottles, often disengage from the underlying cap due to inadequate locking mechanisms, leading to loss and reliability issues.
Innovation Solution
A double-walled cap cover with internal injection and flexible retention wings that snap-lock around the cap's end rim, combined with a protruding tab or fin creating an undercut for enhanced retention, ensuring secure coupling without additional threads.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional locking mechanism with interference coupling is used between the cap cover and the cap, then the cap cover can be easily applied and removed, but the locking is not adequate and the cap cover can disengage and be lost
Solution Approach 1:
The locking mechanism is divided into multiple independent retention means (protrusions and corresponding recesses) distributed around the circumference of the cap cover. This segmentation allows the cap cover to be securely locked through multiple contact points while still enabling easy application and removal by overcoming the retention force at these distributed points.
Solution Approach 2:
The retention means are designed with flexible characteristics, allowing the cap cover to be easily applied by deforming the flexible retention means during insertion, and then automatically locking when the deformation releases. This flexibility provides both ease of operation and reliable locking.
2Reliability
If an undercut coupling is used to provide stable locking, then the cap cover is securely retained, but the manufacturing complexity increases
Solution Approach 1:
Instead of creating an undercut in the cap cover that would require complex mold extraction, the invention inverts the approach by providing retention means that protrude from the cap cover and engage with recesses in the cap. This inversion simplifies the mold design while achieving secure locking through the protrusion-recess engagement.
Solution Approach 2:
The retention means are designed to automatically engage and lock when the cap cover is applied to the cap, without requiring additional manufacturing steps or complex assembly operations. The flexible retention means self-adjust and self-lock during the normal application process.
3Ease of manufacture
If double-walled cap cover with internal injection is used, then the structure is simplified and production is easier, but the undercut cannot be provided for secure locking
Solution Approach 1:
The invention transitions from a two-dimensional surface coupling approach to a three-dimensional protrusion-recess engagement. The retention means extend radially outward from the inner wall of the cap cover, creating a third dimension of engagement that provides secure locking while maintaining compatibility with internal injection molding processes.
Solution Approach 2:
The retention means act as intermediary elements between the cap cover and the cap, providing the locking function without requiring complex features in either component. These protrusions and recesses serve as mediating structures that enable secure coupling while maintaining manufacturing simplicity.
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
A cap assembly for closing a bottle or the like comprises a cap body (2) adapted to be screwed onto a threaded bottle (10), wherein the cap body (2) is protected by a corresponding cap cover (6) of the double-walled type. The cap cover (6) is provided with retention means that comprise a circumferential tab (12) that protrudes from the lower rim of the cap cover (6) and are adapted to retain the cap cover (6) with respect to the cap (1).