Magnetic Abrasive Particle Transfer for Uniform Coating

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional methods for coating abrasive articles, such as drop coating and electrostatic deposition, result in random distribution of abrasive particles, leading to particle clustering and poor cutting performance due to uneven orientation and alignment.

Innovation Solution

The use of magnetic fields to control the orientation and alignment of magnetizable abrasive particles during the transfer from a distribution tool to a backing, allowing for precise positioning and orientation, even with a larger gap between the tool and the backing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If conventional methods (drop coating or electrostatic coating) are used to coat abrasive particles onto a backing, then the coating process is simple and fast, but the abrasive particles are randomly distributed leading to clustering and poor cutting performance

Engineering Contradiction:
Improveparticle distribution uniformityVSAvoidcoating process complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent replaces conventional mechanical coating methods (drop coating, electrostatic coating) with a screen-based mechanical positioning system. The screen with precisely spaced and aligned non-circular apertures mechanically positions each abrasive particle, eliminating random distribution and clustering while maintaining manufacturing efficiency.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent divides the coating process into discrete positioning steps through the screen structure. Each aperture in the screen acts as an independent positioning element, segmenting the continuous coating process into controlled discrete particle placements, which prevents clustering and ensures uniform distribution.

Inventive Principle:
Principle #1Segmentation

2Manufacturing precision

If precision screens with non-circular apertures are used to control abrasive particle orientation, then particle alignment is improved, but the process becomes more complex and requires adhesive which can detackify over time

Engineering Contradiction:
Improveparticle orientation controlVSAvoidscreen and adhesive system complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent extracts and removes the adhesive layer from the precision screen method. By using a perforated plate without adhesive, the system eliminates the detackifying problem while maintaining particle orientation control through the geometric constraints of the non-circular apertures alone.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent inverts the conventional approach by using the aperture geometry itself to control particle orientation rather than relying on adhesive properties. The non-circular aperture shapes (such as rectangles or triangles) mechanically constrain particle orientation through their geometric features, reversing the dependency from chemical adhesion to mechanical positioning.

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

3Manufacturing precision

If adhesive is used to transfer abrasive particles from the screen to the backing, then particle transfer is achieved, but adhesive can transfer to the workpiece causing contamination

Engineering Contradiction:
Improveparticle transfer accuracyVSAvoidadhesive contamination of workpiece
Core Design Contradiction:
Manufacturing precisionVSObject-affected harmful factors

Solution Approach 1:

The patent completely removes the adhesive substance from the particle transfer process. By using a perforated plate without adhesive and relying on mechanical positioning through aperture geometry, the system eliminates the source of contamination while maintaining accurate particle transfer to the backing.

Inventive Principle:
Principle #2Taking out (Extraction)

4Manufacturing precision

If a small gap is maintained between the distribution tool and backing for particle transfer, then particle positioning is more precise, but the tool is more prone to fouling and damage

Engineering Contradiction:
Improveparticle positioning accuracyVSAvoidtool durability and fouling resistance
Core Design Contradiction:
Manufacturing precisionVSReliability

Solution Approach 1:

The patent uses the z-dimensional orientation control provided by the non-circular aperture geometry to maintain precise particle positioning even when the gap between the distribution tool and backing is increased. The aperture shape constraints ensure particles maintain correct orientation regardless of gap variations, decoupling positioning precision from gap distance.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

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 method achieves a predetermined and non-random pattern of abrasive particles, enhancing cutting performance and durability by maintaining particle alignment and orientation, while also preventing fouling and damage to the abrasive article.

Implementation Method 1

applying a magnetic field to at least the backing and a portion of the gap between the backing and the distribution tool to exert a magnetic force on the magnetizable abrasive particles to influence transfer of the magnetizable abrasive particles from the distribution tool to the backing

Methodology Applied
Scientific EffectMagnetic force: Magnetic Field

Implementation Method 2

The magnetic field can be applied to the magnetizable abrasive particles during transfer from the distribution tool to the backing to improve not just the drop height but the propensity of the magnetizable abrasive particles to be oriented and/or aligned as desired once received on the backing

Methodology Applied
Scientific EffectMagnetic field: Magnetic Field

Data Source

PatentEP3571011B1Magnetically assisted transfer of magnetizable abrasive particles and methods, apparatuses and systems related thereto
Publication Date: 2025.04.23 3M INNOVATIVE PROPERTIES CO
  • EP3571011B1 patent drawingFigure 1~1A
  • EP3571011B1 patent drawingFigure 2
  • EP3571011B1 patent drawingFigure 2A~3

AI summary

According to one embodiment, a method of making an abrasive layer on a backing is disclosed. The method can comprise: providing dispensable magnetizable abrasive particles and a distribution tool, wherein the distribution tool is configured to receive the magnetizable abrasive particles therein, and wherein the distribution tool is configured to impart at least one of a predetermined orientation and alignment of the magnetizable abrasive particles, positioning a backing adjacent to the distribution tool and spaced therefrom by a gap, applying a magnetic field to at least the backing and a portion of the gap between the backing and the distribution tool, and transferring the magnetizable abrasive particles from the distribution tool to a first major surface of the backing, wherein the magnetic field is applied during the transfer of the magnetizable abrasive particles.