Centrifugal Rotor Mass Balancer for Nanoparticle Classification

Solution Overview

Problem

Conventional centrifugal separation type FFF devices face limitations in classifying smaller particles due to instability in centrifugal force distribution and risk of rotor damage at high rotational speeds, making it difficult to achieve precise classification of nanoparticles smaller than 10 nm.

Innovation Solution

A rotor design with a mass balancer portion to adjust mass distribution, allowing for high-speed rotation without bending, and a channel installation portion with varying thickness to distribute stress evenly, ensuring stable centrifugal force application and preventing rotor deformation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If the rotor rotates at high speed to classify smaller particles, then the classification precision for nanoparticles is improved, but the rotor stability deteriorates and the risk of rotor damage increases

Engineering Contradiction:

Improveclassification precisionVSAvoidrotor stability

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The patent applies the counterweight principle by adding a mass balancer portion to the rotor structure. This additional mass is strategically positioned to balance the centrifugal forces generated during high-speed rotation, preventing rotor bending and instability. The mass balancer portion acts as a counterweight that compensates for the uneven mass distribution caused by the channel and other rotor components, enabling the rotor to maintain stability at the high rotational speeds necessary for classifying nanoparticles.

Inventive Principle:

Principle #8Anti-weight (Counterweight)

2Force

If the rotor rotates at high speed to apply greater centrifugal force, then the classification capability for smaller particles is improved, but the stress on connection points increases causing potential rotor damage

Engineering Contradiction:

Improvecentrifugal forceVSAvoidrotor strength

Core Design Contradiction:

ForceVSStrength

Solution Approach 1:

The patent applies the local quality principle by varying the thickness of the rotor wall in different regions. The rotor wall is designed to be thicker at the connection points between the channel and the rotor base, and thinner in other regions. This non-uniform thickness distribution strategically reinforces the areas subjected to highest stress during high-speed rotation, allowing the rotor to withstand the greater centrifugal forces needed for nanoparticle classification without unnecessary weight increase throughout the entire structure.

Inventive Principle:

Principle #3Local quality

3Reliability

If the rotor structure is reinforced to prevent bending at high speed, then the rotor stability is improved, but the device weight increases

Engineering Contradiction:

Improverotor stabilityVSAvoidrotor weight

Core Design Contradiction:

ReliabilityVSWeight of moving object

Solution Approach 1:

The patent applies the local quality principle by varying the thickness of the rotor wall in different regions. The rotor wall is designed to be thicker at the connection points between the channel and the rotor base, and thinner in other regions. This non-uniform thickness distribution strategically reinforces the areas subjected to highest stress during high-speed rotation, allowing the rotor to withstand the greater centrifugal forces needed for nanoparticle classification without unnecessary weight increase throughout the entire structure.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent applies the counterweight principle by adding a mass balancer portion to the rotor structure. This additional mass is strategically positioned to balance the centrifugal forces generated during high-speed rotation, preventing rotor bending and instability. The mass balancer portion acts as a counterweight that compensates for the uneven mass distribution caused by the channel and other rotor components, enabling the rotor to maintain stability at the high rotational speeds necessary for classifying nanoparticles.

Inventive Principle:

Principle #8Anti-weight (Counterweight)

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

Enables safe and precise classification of smaller particles by maintaining rotor stability and reducing stress on connection points, allowing for higher centrifugal forces without increasing device size or weight.

Implementation Method 1

a centrifugal separation type FFF device where a liquid that includes a group of microscopic particles is allowed to pass through a channel that is rotating at a high speed so that the microscopic particles in the liquid are classified into groups of the respective particle sizes by means of the centrifugal force

Methodology Applied

Scientific EffectCentrifugal force: Centrifugal Force

Data Source

PatentUS11774412B2Field flow fractionation device including mass balancer portion

Publication Date: 2023.10.03 SHIMADZU CORP

AI summary

A centrifugal separation type FFF device where a rotor can be rotated at a high speed safely so that particles of a smaller size in a sample liquid can be classified. A field flow fractionation device is provided with: a channel that is attached to the inner circumferential surface of the peripheral portion of a rotor and where a classification flow path is created; flow paths for feeding a sample liquid into and out from the classification flow path; and a rotational drive mechanism for rotating the rotational axis, wherein a channel installation portion is formed on one side of the peripheral portion, and a mass balancer portion for adjusting the mass distribution of the rotor is formed on the other side with the rotor base in between.