Dialysis Apparatus Using Reverse Filtration for Air Bubble Removal

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional dialysis apparatuses require cumbersome manual procedures to eliminate air bubbles during the priming process, especially when the dialyzer is positioned with the vein passage facing upward, necessitating inversion to facilitate bubble removal.

Innovation Solution

The dialysis apparatus incorporates a bypass passage, pressurizing and depressurizing devices, and control mechanisms to reverse-filter priming fluid through the blood purification membrane, creating a pressure difference to efficiently discharge air bubbles without inverting the dialyzer.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the dialyzer is filled with priming fluid while the vein passage is facing upward, then the dialyzer can be positioned in the correct orientation for dialysis treatment, but air bubbles accumulate in the upper part of the dialyzer

Engineering Contradiction:
Improvedialyzer positioningVSAvoidair bubble accumulation
Core Design Contradiction:
Ease of operationVSObject-generated harmful factors

Solution Approach 1:

The patent applies reverse filtration through the blood purification membrane to expel air bubbles from the dialysis fluid flow path. By pressurizing the blood flow path and creating reverse pressure gradient, the priming fluid flows backward through the membrane, carrying air bubbles from the upper part of the dialyzer down to the lower part where they can be discharged, effectively inverting the bubble removal direction

Inventive Principle:
Principle #13The other way round (Inversion)

Solution Approach 2:

The patent uses pressure differential control through the pressurizing device and depressurizing device to manipulate fluid flow. By controlling pressure in the blood flow path and dialysis fluid flow path, the system creates hydraulic conditions that drive priming fluid and air bubbles through the dialyzer in a controlled manner, enabling automatic bubble removal without manual intervention

Inventive Principle:
Principle #29Pneumatics and hydraulics

2Object-generated harmful factors

If manual procedures are used to eliminate air bubbles by inverting the dialyzer, then air bubbles can be removed from the dialyzer, but the procedure becomes cumbersome requiring monitoring and manual work

Engineering Contradiction:
Improveair bubble removalVSAvoidmanual operation complexity
Core Design Contradiction:
Object-generated harmful factorsVSDevice complexity

Solution Approach 1:

The patent implements an automatic air bubble removal system that operates without manual intervention. The controlling device automatically controls the open/close valves, pressurizing device, and depressurizing device to perform the entire priming and bubble removal process autonomously. The system uses sensors to detect air bubbles and automatically adjusts pressure and flow to expel them, making the system self-servicing

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The patent incorporates feedback mechanisms through air bubble detection sensors that monitor the dialysis fluid flow path. The sensor signals are fed back to the controlling device, which automatically adjusts the pressure and flow conditions to continue bubble removal until the path is clear, creating a closed-loop control system that eliminates the need for manual monitoring

Inventive Principle:
Principle #23Feedback

3Object-generated harmful factors

If the dialyzer is inverted to remove air bubbles, then air bubbles can be discharged, but the procedure requires additional time and manual intervention

Engineering Contradiction:
Improveair bubble dischargeVSAvoidpriming procedure time
Core Design Contradiction:
Object-generated harmful factorsVSLoss of time

Solution Approach 1:

The patent maintains continuous fluid flow and pressure application throughout the priming and bubble removal process. Instead of stopping to manually invert the dialyzer, the system continuously pressurizes and circulates priming fluid, maintaining unbroken flow that progressively pushes air bubbles through the dialyzer and into the discharge path, eliminating interruptions and reducing total time

Inventive Principle:
Principle #20Continuity of useful action

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 configuration allows for efficient air bubble removal within the dialyzer without manual intervention, reducing worker burden and enhancing the priming procedure's efficiency.

Implementation Method 1

pressurizing device for pressurizing the dialysis fluid circuit

Methodology Applied
Scientific EffectPressure gradient: Pressure Gradient

Implementation Method 2

causes the depressurizing device to depressurize the dialysis fluid circuit to cause a pressure difference between the blood circuit and the dialysis fluid circuit

Methodology Applied
Scientific EffectPressure difference: Pressure Gradient

Implementation Method 3

causes the priming fluid to be reversely filtered through the blood purification membrane

Methodology Applied
Scientific EffectReverse filtration: Reverse Osmosis

Data Source

PatentEP4623948A1Dialysis apparatus
Publication Date: 2025.10.01 SHIBUYA IND CO LTD
  • EP4623948A1 patent drawingFigure 1
  • EP4623948A1 patent drawingFigure 2(a)~2(c)
  • EP4623948A1 patent drawingFigure 3

AI summary

An object is to perform priming procedures efficiently. During a priming procedure, a state in which a vein passage 3A is connected to an upper position is maintained. While a dialysis fluid supply open/close valve V9 is closed, and a dialysis fluid retrieval open/close valve V10 is open, pressurizing device operates to cause a priming fluid to flow through a dialysis fluid retrieval passage 4B into a dialyzer 2. Thus, the priming fluid in a dialysis fluid flow path 12b is reversely filtered through a hollow fiber 12 (blood purification membrane), so that a blood flow path 12a is filled with the priming fluid and pressurized (b). Subsequently, after the dialysis fluid retrieval open/close valve V10 is closed, depressurizing device depressurizes a dialysis fluid circuit 4 to cause a pressure difference between a blood circuit 3 and the dialysis fluid circuit 4. When the dialysis fluid supply open/close valve V9 provided on a dialysis fluid supply passage 4A is opened, the priming fluid in the blood flow path 12a is, due to the pressure difference, filtered forward through the hollow fiber 12, and the priming fluid in the blood flow path 12a flows into the dialysis fluid flow path 12b, so that air bubbles B remaining in an upper part of the dialysis fluid flow path 12b are eliminated (c).