Needle Guard Biased Arms Secure IV Catheter Tip

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Solution Overview

Problem

Existing safety intravenous catheters (IVCs) often fail to reliably prevent unintended needlesticks due to unreliable engagement between the needle and the needle guard during withdrawal, leading to potential exposure to blood-borne pathogens.

Innovation Solution

A safety IVC design featuring a non-metallic needle guard with a biased first and second arm, an angled end section, and a metal insert, which moves between a ready and protected position to securely cover the needle tip, utilizing a combination of materials and structural features to enhance retention and protection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If a needle guard is used to cover the needle tip during withdrawal, then the risk of accidental needlestick is reduced, but the engagement between the needle and guard becomes unreliable allowing the needle tip to slide out

Engineering Contradiction:
Improveaccidental needlestick riskVSAvoidengagement reliability
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The needle guard incorporates a biased arm mechanism that dynamically transitions between positions. The arm is biased toward a first position where it engages the needle during insertion, and automatically moves to a second position that securely confines the needle tip during withdrawal, ensuring reliable engagement throughout the procedure.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The engagement mechanism changes its geometric parameters based on needle position. During insertion, the arm engages the needle shaft at a specific location, while during withdrawal, the configuration changes to confine the needle tip within the guard, adapting the retention parameters to the operational phase.

Inventive Principle:
Principle #35Parameter changes

2Ease of manufacture

If the needle guard structure is simplified for ease of manufacture, then production cost decreases, but the ability to prevent needle tip exposure during rotation is compromised

Engineering Contradiction:
Improvemanufacturing simplicityVSAvoidneedle tip retention during rotation
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The needle guard is segmented into distinct functional components: a body portion, a biased arm with a first engagement feature for the needle shaft, and a second engagement feature for confining the needle tip. This segmentation allows each component to be optimized for its specific function while maintaining overall manufacturing simplicity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The biased arm functions as a flexible element that can deflect and return to its biased position. This flexibility allows the arm to automatically transition between engagement states and maintain reliable needle tip confinement during rotation without requiring complex mechanical structures.

Inventive Principle:
Principle #30Flexible shells and thin films

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 design effectively prevents needle tip exposure by ensuring the needle is securely confined within the guard, even during rotation or pivoting, and increases the detachment force required to separate the needle from the guard, thereby enhancing safety for healthcare workers.

Implementation Method 1

a first arm including a first free end and a second arm including a second free end extending generally axially from the base portion in a distal direction. The first free end extending beyond the second free end and including an angled end section that extends toward the second arm

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

The first arm and the second arm are biased so as to move between a ready position in which the angled end section abuts a needle having a needle tip and a protected position in which the needle tip is confined within a tip holding space

Methodology Applied
Scientific EffectSpring mechanism: Spring

Data Source

PatentEP3967344A1Needle safety device and assembly
Publication Date: 2022.03.16 B BRAUN MELSUNGEN AG
  • EP3967344A1 patent drawingFigure 1
  • EP3967344A1 patent drawingFigure 2
  • EP3967344A1 patent drawingFigure 2A

AI summary

Safety IV catheter assemblies (IVCs) are disclosed herein comprising a needle hub with a needle (202) having a needle tip and a needle diameter, a catheter hub (102) with a catheter tube (112), and a tip protector or needle guard (44, 204) made from a first material comprising a proximal wall comprising an opening defining a bore (207) and two arms (206, 208) extending distally of the proximal wall, wherein at least one of the arms (206, 208) comprises an angled end section (214), and wherein an insert (404) made from a second material comprising an opening is aligned with the opening (207) of the proximal wall of the tip protector or needle guard (44, 204).