Face Shield Lens Lock Mechanism for Quick Replacement

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional face shield systems require significant time and effort to remove and replace worn or damaged lenses and seal components, and are prone to inadvertent release.

Innovation Solution

The face shield system incorporates a lens lock mechanism that allows for easy removal and installation of the face shield lens without removing the shell from the user's head, and includes mechanical attachment locations for components like the head seal, which can be replaced with less effort and time.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If conventional lens replacement methods are used, then the face shield can be maintained and cleaned, but significant time and effort are required to remove and install replacement lenses

Engineering Contradiction:
ImproveEase of lens replacementVSAvoidTime required for lens replacement
Core Design Contradiction:
Ease of manufactureVSLoss of time

Solution Approach 1:

The face shield is divided into separable components: a reusable shell and replaceable lenses. The lens retention system is further segmented into discrete lens locks that can independently secure individual lenses, allowing for efficient replacement without affecting other components.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The lens retention system transitions from static permanent attachment to dynamic reversible attachment. Lens locks can be easily engaged and disengaged, allowing the lens to be quickly removed and replaced while maintaining secure attachment during use.

Inventive Principle:
Principle #15Dynamics

2Reliability

If conventional lens retention systems are used, then lenses can be secured to the face shield shell, but the system is prone to inadvertent release

Engineering Contradiction:
ImproveLens retention reliabilityVSAvoidEase of lens removal
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The lens locks feature asymmetric geometry with specific engagement surfaces and locking positions that prevent accidental disengagement. The locks are designed to require deliberate user action to release, ensuring lenses remain securely attached during normal use while allowing easy removal when intended.

Inventive Principle:
Principle #4Asymmetry

3Ease of manufacture

If the face shield shell is removed from the user's head to replace the lens, then proper lens replacement can be performed, but the process becomes more time-consuming and complex

Engineering Contradiction:
ImproveEase of lens replacementVSAvoidComplexity of replacement process
Core Design Contradiction:
Ease of manufactureVSDevice complexity

Solution Approach 1:

The retention system separates the lens securing function from the headwear function. Lens locks are integrated into the shell and can operate independently, allowing lens replacement to be performed as a simple local operation without disturbing the overall face shield assembly or requiring removal from the head.

Inventive Principle:
Principle #1Segmentation

4Reliability

If mechanical attachment locations are used for seal components, then seals can be secured to the shell, but significant time and effort are required to replace them

Engineering Contradiction:
ImproveSeal attachment reliabilityVSAvoidTime required for seal replacement
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

Seal components utilize dynamic attachment mechanisms that allow for quick engagement and disengagement. The mechanical attachment locations are designed to accommodate rapid replacement while maintaining secure attachment during use, reducing both the time required for replacement and the effort needed to perform it.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP3944781B1Face shield systems for securing removable face shield lenses
Publication Date: 2025.04.09 ILLINOIS TOOL WORKS INC
  • EP3944781B1 patent drawingFigure 1
  • EP3944781B1 patent drawingFigure 2A~2B
  • EP3944781B1 patent drawingFigure 2C~2D

AI summary

A face shield (100) includes a face shield lens (104) comprising a locking channel (302), a face shield shell (102) configured to receive the face shield lens when the face shield is inserted into the face shield shell, and a lens lock (110) configured to move between: a locked position in which the lens lock is configured to engage the locking channel of the face shield to secure the face shield lens to the face shield shell; and an unlocked position in which the lens lock is configured to disengage the locking channel of the face shield to permit insertion of the face shield to the face shield shell and removal of the face shield from the face shield shell.