Drip Chamber Variable-Orifice Assembly for Clogging-Resistant Infusion

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing drip chamber arrangements for medical infusion devices face challenges in simplified production and assembly, and are prone to liquid adhesion and clogging due to elongated flow resistances, which compromise patient safety.

Innovation Solution

A drip chamber arrangement with a diaphragm-based flow resistance mechanism, where the cross-section is varied by an actuating element, forming a locally limited orifice with a short effective length, eliminating the need for complex throttle channels and reducing clogging risks.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If elongated throttle channels or capillaries are used as flow resistance, then flow rate control is achieved, but liquid adhesion and clogging occur due to long contact length

Engineering Contradiction:
Improveclogging resistanceVSAvoidflow resistance structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The invention extracts the flow resistance function from a distributed elongated structure and concentrates it into a localized orifice plate with a hole or slit. This orifice plate has an effective flow length that is comparatively short relative to its effective flow cross-section, eliminating the clogging issues associated with long throttle channels while maintaining flow control capability

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention changes the geometric parameters of the flow resistance structure by using an orifice plate where the effective flow length is significantly shorter than the effective flow cross-section dimensions. This parameter inversion (short length, larger cross-section) prevents liquid adhesion and clogging that occur in traditional elongated throttle channels

Inventive Principle:
Principle #35Parameter changes

2Ease of manufacture

If traditional throttle channels are used, then flow rate adjustment is possible, but production and assembly become complex

Engineering Contradiction:
Improveproduction simplicityVSAvoidthrottle channel structure
Core Design Contradiction:
Ease of manufactureVSDevice complexity

Solution Approach 1:

The invention merges the flow resistance function into the orifice plate structure itself, which can be integrated into the drip chamber housing or adjusting device assembly. This eliminates the need for separate complex throttle channels, simplifying both production and assembly processes while maintaining flow control functionality

Inventive Principle:
Principle #5Merging (Combining)

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

This design simplifies production and assembly, reduces clogging, and enhances patient safety by preventing undesired fluid blockages, ensuring precise fluid administration.

Implementation Method 1

the orifice plate naturally forms a merely locally limited constriction with a comparatively short effective flow length. The solution according to the invention counteracts this, since the orifice plate naturally forms a merely locally limited constriction with a comparatively short effective flow length. Due to the resulting comparatively long contact length between the constriction and the liquid, adhesion of the liquid to the constriction and clogging of the same cannot be avoided under certain circumstances.

Methodology Applied
Scientific EffectFluid dynamics - adhesion and clogging prevention:

Data Source

PatentEP3711792B1Drip chamber assembly for a medical infusion device
Publication Date: 2025.09.03 B BRAUN MELSUNGEN AG
  • EP3711792B1 patent drawingFigure 1
  • EP3711792B1 patent drawingFigure 2~3
  • EP3711792B1 patent drawingFigure 4

AI summary

2.1 Such a drip chamber arrangement comprising a drip chamber housing that encloses a drip chamber for receiving the liquid and has an inlet for introducing the liquid into the drip chamber and a passage for draining the liquid from the drip chamber, and an adjusting device that allows manual adjustment of a flow rate of the liquid to be drained from the passage of the drip chamber, wherein the adjusting device has an actuating element that is movably mounted on the drip chamber housing relative to the drip chamber housing between different displacement positions, and a fluid channel with a flow resistance that is fluidly connected at one end to the passage and opens at the other end into an outlet of the adjusting device, and wherein the flow resistance is operatively connected to the actuating element and is variable as a function of the displacement position of the actuating element to adjust the flow rate to be drained,is known. 2.2 According to the invention, the flow resistance is an orifice having a cross-section that varies depending on the displacement position of the actuating element and a constant length. 2.3 Use in infusion therapy.