Single-Use Syringe Plunger With Impulse Reduction To Limit Fluid Spray

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing syringes with breakable plunger rods face issues where the breakage of the connection results in a high contact impulse, leading to the spraying of residual fluids, posing a risk of contamination.

Innovation Solution

A syringe design incorporating a breakable connection between the plunger's proximal and distal portions, equipped with an impulse reduction system featuring sloped braking surfaces or elastic elements to mitigate the contact impulse upon breakage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a breakable connection is provided between the proximal and distal portions of the plunger rod, then the syringe is disabled after use to prevent re-use, but the contact impulse upon breakage causes residual fluids to spray from the tip

Engineering Contradiction:
Improveprevention of re-useVSAvoidfluid spray
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

An impulse reduction system is disposed between the proximal and distal portions of the plunger rod to cushion the contact impulse before it can cause fluid spray. This system includes a compressible element that compresses upon breakage, absorbing the impact energy and preventing the harmful fluid spray effect.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

2Strength

If the breakable connection is made strong enough to resist breakage during normal use, then structural integrity is maintained, but the breaking force required may be excessively high

Engineering Contradiction:
Improvestructural integrityVSAvoidbreaking force
Core Design Contradiction:
StrengthVSEase of operation

Solution Approach 1:

The breakable connection is designed with specific material properties and geometric parameters that allow it to withstand normal use forces while failing at a controlled, reasonable breaking force. The connection strength parameters are optimized to balance durability during operation with ease of breaking after use.

Inventive Principle:
Principle #35Parameter changes

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 impulse reduction system effectively reduces the contact impulse, minimizing fluid spray and preventing contamination, while ensuring easy breakage of the connection under controlled conditions.

Implementation Method 1

The braking surfaces are designed to slidingly engage with each other to create a motion-resistive force between the proximal portion and the distal portion

Methodology Applied
Scientific EffectFriction: Friction

Implementation Method 2

an elastic element, such as a spring or similar device, disposed within a gap that separates the proximal portion from the distal portion

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP3915617B1Single use syringe with impulse reduction system
Publication Date: 2025.07.09 BECTON DICKINSON & CO
  • EP3915617B1 patent drawingFigure 1
  • EP3915617B1 patent drawingFigure 2
  • EP3915617B1 patent drawingFigure 3~4

AI summary

A syringe including a plunger rod assembly including a proximal portion (36) a distal portion (34) with a stopper (38) for expelling fluids from the syringe and a breakable connection between the proximal portion and the distal portion is disclosed. An impulse reduction system (50), which may be an elastic element or braking surfaces, reduces the contact impulse imparted by the proximal portion upon the distal portion when the connection between the distal portion and proximal portion breaks is also disclosed.