Container Lid Snap-Fit Mechanism Eliminating Adhesives

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing container lids require adhesive products for connection, increasing manufacturing costs and time, and existing snap-fit designs lack stability during opening and closing.

Innovation Solution

A container lid design featuring a snap-fitting mechanism with a protrusion and perimeter cavity, and a milled surface finish to prevent rotation, eliminating the need for adhesives and ensuring secure engagement between the inner and external bodies.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If adhesive products are used to connect the two bodies of the lid, then the connection strength is improved, but the manufacturing cost and time increase

Engineering Contradiction:
Improveconnection strengthVSAvoidmanufacturing time
Core Design Contradiction:
StrengthVSLoss of time

Solution Approach 1:

The patent replaces the chemical bonding mechanism of adhesives with a mechanical snap-fit system. The first body includes a protrusion that engages with a corresponding recess in the second body, creating a purely mechanical connection that eliminates the need for adhesive products, thereby reducing manufacturing time and cost while maintaining connection strength

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The lid is divided into two separate bodies (first body and second body) that can be manufactured independently and then assembled through the snap-fit mechanism. This segmentation allows for simplified manufacturing of each component while enabling easy assembly without adhesives, addressing both the strength and time requirements

Inventive Principle:
Principle #1Segmentation

2Strength

If adhesive products are used to connect the two bodies of the lid, then the connection strength is improved, but the manufacturing cost increases

Engineering Contradiction:
Improveconnection strengthVSAvoidmanufacturing cost
Core Design Contradiction:
StrengthVSEase of manufacture

Solution Approach 1:

The patent replaces the chemical bonding mechanism of adhesives with a mechanical snap-fit system. The first body includes a protrusion that engages with a corresponding recess in the second body, creating a purely mechanical connection that eliminates the need for adhesive products, thereby reducing manufacturing cost while maintaining connection strength

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The snap-fit mechanism is designed to be self-aligning and self-assembling. The geometric features (protrusion and recess) automatically guide the components into correct positioning during assembly, eliminating the need for additional alignment procedures or adhesive application steps, thus reducing both cost and complexity

Inventive Principle:
Principle #25Self-service

3Ease of manufacture

If a simple snap-fit design is used to connect the two bodies, then the manufacturing cost is reduced, but the stability during opening and closing deteriorates

Engineering Contradiction:
Improvemanufacturing costVSAvoidstability during operation
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The protrusion and recess are designed with asymmetric geometries that provide both easy assembly and stable engagement. The asymmetric shape ensures that the components can only be assembled in the correct orientation, providing inherent alignment while creating a secure mechanical interlock that prevents unintended movement during operation

Inventive Principle:
Principle #4Asymmetry

Solution Approach 2:

The patent incorporates curved or rounded features in the protrusion and recess designs, which facilitate smooth engagement and disengagement during opening and closing operations. The curved geometry distributes contact forces more evenly, enhancing the stability and reliability of the connection while maintaining the simplicity of the snap-fit mechanism

Inventive Principle:
Principle #14Spheroidality (Curvature)

Data Source

PatentEP1820746B1Improved lid for containers
Publication Date: 2009.08.12 CANAMASAS PUIGBO ANICETO
  • EP1820746B1 patent drawingFigure 1~3

AI summary

Improved lid for containers that is made up from an inner body (1) that is fitted to a container on its outside part and by a second external body (2) in such a way that it encloses said inner body (1) by its external face, where the fitting of both bodies (1, 2) to each other is carried out by means of snap fitting, the said fitting together having being provided with a protrusion (3) on the inner edge of the inner body (1) that protrudes perpendicularly to the outside and which has a perimeter cavity (3A) into which a rib (4) is introduced which is an extension from the lower part of the external body (2).