Refrigerant Compressor Oxide Coating for Low-Viscosity Wear Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional refrigerant compressors face issues with abrasion resistance due to the degradation of phosphate coating films when using lubricating oils with lower viscosity or shorter slide lengths, leading to increased friction coefficients and abnormal abrasion, particularly in regions between the crankshaft and bearing sections.

Innovation Solution

A refrigerant compressor with an oxide coating film comprising diiron trioxide (Fe2O3), triiron tetraoxide (Fe3O4), and silicon compounds on iron-based materials, structured in layers to enhance abrasion resistance and adhesivity, allowing for reduced viscosity lubricating oils and shorter slide lengths without excessive wear.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If phosphate coating film is formed on slide surface to prevent abrasion, then initial conformability between slide members is improved, but the coating film degrades when using lubricating oils with lower viscosity or shorter slide lengths, leading to increased abrasion

Engineering Contradiction:
Improveabrasion resistanceVSAvoidservice life of coating film
Core Design Contradiction:
ReliabilityVSDuration of action of moving object

Solution Approach 1:

The patent changes the chemical composition parameters of the coating film from phosphate-based to oxide-based (specifically Fe2O3 and Fe3O4), which fundamentally alters the coating's properties to be more resistant to degradation under modern lubrication conditions with lower viscosity oils and shorter slide lengths

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite oxide coating film containing multiple iron oxide phases (Fe2O3 and Fe3O4) in specific proportions, combining the advantages of different oxide structures to achieve both conformability and exceptional abrasion resistance that maintains durability under reduced lubrication conditions

Inventive Principle:
Principle #40Composite materials

2Loss of energy

If lubricating oil with lower viscosity is used to reduce friction, then energy efficiency is improved, but the phosphate coating film degrades faster leading to abnormal abrasion

Engineering Contradiction:
Improvefriction lossVSAvoidcoating film stability
Core Design Contradiction:
Loss of energyVSReliability

Solution Approach 1:

The patent changes the coating material composition from phosphate to oxide (Fe2O3 and Fe3O4), which fundamentally alters the coating's chemical stability and mechanical properties to resist degradation even when used with lower viscosity lubricating oils that provide reduced friction and energy loss

Inventive Principle:
Principle #35Parameter changes

3Productivity

If slide length is shortened to improve compressor efficiency, then productivity is improved, but the phosphate coating film cannot maintain conformability leading to increased abrasion

Engineering Contradiction:
Improvecompression efficiencyVSAvoidslide surface durability
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent changes the coating composition to oxide-based materials (Fe2O3 and Fe3O4) which provide different tribological properties compared to phosphate coatings, enabling the coating to maintain conformability and protective function even when the slide length is shortened to improve overall compressor efficiency

Inventive Principle:
Principle #35Parameter changes

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

The solution improves the reliability and efficiency of the refrigerant compressor by reducing sliding losses and preventing abnormal abrasion, thereby enhancing the compressor's performance and longevity.

Implementation Method 1

an oxide coating film is provided on a slide surface of the iron-based material, the oxide coating film comprising: a composition A portion containing diiron trioxide (Fe 2 O 3 ) which is more in quantity than other substances; a composition B portion containing triiron tetraoxide (Fe 3 O 4 ) which is more in quantity than other substances

Methodology Applied
Scientific EffectLubrication: Lubrication

Data Source

PatentEP3348832B1Refrigerant compressor and refrigerating device including same
Publication Date: 2019.11.27 PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO LTD
  • EP3348832B1 patent drawingFigure 1
  • EP3348832B1 patent drawingFigure 2A~2D
  • EP3348832B1 patent drawingFigure 3A~3F

AI summary

A refrigerant compressor reserves lubricating oil in a sealed container, and accommodates therein an electric component, and a compression component which is driven by the electric component and compresses a refrigerant. At least one of slide members included in the compression component is made of an iron-based material, and an oxide coating film comprising a composition A portion, a composition B portion, and a composition C portion is provided on a slide surface of the iron-based material. The composition A portion is a portion containing diiron trioxide (Fe2O3) which is more in quantity than other substances, and is, for example, an outermost portion (160a). The composition B portion is a portion containing triiron tetraoxide (Fe3O4) which is more in quantity than other substances and containing a silicon (Si) compound, and is, for example, an intermediate portion (160b). The composition C portion is a portion containing triiron tetraoxide (Fe3O4) which is more in quantity than other substances and containing silicon (Si) which is more in quantity than silicon (Si) of the composition B portion, and is, for example, an inner portion (160c).