Analyzer Dispensing Nozzle Air Purge Against Reagent Dilution

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing automatic analyzers dilute reagents due to mechanical backlash during dispensing operations, leading to inaccurate measurement results when reagents are repeatedly discharged back to containers.

Innovation Solution

The automatic analyzer performs air aspiration and discharge operations during nozzle movement to prevent reagents from being diluted by system water, ensuring accurate dispensing without backlash.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If the syringe performs a discharge operation to avoid backlash while immersed under the liquid surface, then the backlash is removed and dispensing accuracy is improved, but the reagent is diluted by system water remaining on the inner wall of the nozzle

Engineering Contradiction:
Improvedispensing accuracyVSAvoidreagent concentration
Core Design Contradiction:
Manufacturing precisionVSQuantity of substance

Solution Approach 1:

Air is introduced as an intermediary substance between the system water and the reagent. The air aspiration operation draws air into the nozzle, and the air discharge operation expels the air (along with adhering system water) to the atmosphere or into the reaction container, preventing the system water from mixing with and diluting the reagent in the reagent container.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Productivity

If the nozzle is repeatedly immersed under the liquid surface for dispensing operations, then the dispensing function is maintained, but the accumulated system water dilutes the reagent in the container

Engineering Contradiction:
Improvedispensing frequencyVSAvoidreagent concentration
Core Design Contradiction:
ProductivityVSQuantity of substance

Solution Approach 1:

Air serves as a mediator that separates the system water from the reagent during repeated dispensing operations. By aspirating and discharging air, the system water adhering to the nozzle inner wall is expelled without contacting the reagent in the reagent container, allowing repeated dispensing without cumulative dilution.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

Air creates an inert environment between the system water and the reagent during the air discharge operation. The discharged air carries away the system water to the atmosphere or into the reaction container, preventing contamination of the reagent in the reagent container and enabling repeated operations without dilution.

Inventive Principle:
Principle #39Inert atmosphere (Inert environment)

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

Prevents reagent dilution, maintaining measurement accuracy and reducing the need for frequent reagent replacements, thereby enhancing the reliability of analysis results.

Implementation Method 1

the syringe performs an air aspiration operation of aspirating air and an air discharge operation of discharging a part of the aspirated air during movement of the nozzle from the reagent container or the sample container to the reaction container

Methodology Applied
Scientific EffectAir aspiration and discharge:

Data Source

PatentEP4657076A1Automatic analysis device
Publication Date: 2025.12.03 HITACHI HIGH TECH CORP
  • EP4657076A1 patent drawingFigure 1
  • EP4657076A1 patent drawingFigure 2
  • EP4657076A1 patent drawingFigure 3

AI summary

Provided is an automatic analyzer capable of preventing a reagent or the like from being thinned even when the reagent or the like is repeated dispensing. In the automatic analyzer including a dispensing mechanism configured to dispense the reagent or a sample into a reaction container by operating a syringe connected to a nozzle, after the syringe performs an operation of aspirating a predetermined amount of the reagent or the sample in a state where the nozzle is immersed under a liquid surface in a reagent container or a sample container, the syringe performs an air aspiration operation of aspirating air and an air discharge operation of discharging a part of the aspirated air during movement of the nozzle from the reagent container or the sample container to the reaction container, and after the nozzle moves to the reaction container, the syringe performs an operation of discharging a rest of the aspirated air and the predetermined amount of the reagent or the sample to the reaction container.