Rotary Compressor Centrifugal Oil Separator Vibration Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional scroll compressors face challenges in oil separation efficiency due to the vibration and instability of centrifugal separating members, which affects the reliability and efficiency of refrigerant compression, especially at high and low speeds.

Innovation Solution

The oil-separator is directly connected to the rotation shaft, with a coupler ensuring concentric rotation and a centrifugal separator extending beyond the rotor to maximize centrifugal force, reducing vibration and improving separation efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a centrifugal separating member is used to separate oil from refrigerant, then oil separation efficiency is improved, but vibration and instability increase affecting reliability

Engineering Contradiction:
Improveseparation efficiencyVSAvoidvibration
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The oil separator is merged with the drive unit to form an integrated assembly. The oil separator becomes an integral part of the drive unit structure, sharing the same rotational axis and housing. This merging eliminates relative motion between the oil separator and drive unit, reducing vibration and improving operational reliability while maintaining effective oil separation through centrifugal force.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The oil separator is positioned such that its rotational axis coincides with the rotational axis of the drive unit, creating a concentric configuration. This equipotential alignment ensures that both components rotate together without relative motion, eliminating centrifugal imbalances and vibration that would occur with eccentric positioning, thereby improving reliability while maintaining separation efficiency.

Inventive Principle:
Principle #12Equipotentiality

2Volume of stationary object

If the compression unit is disposed above the drive unit close to the discharge part, then space is saved, but oil supply into the compression unit becomes difficult

Engineering Contradiction:
Improvecompressor spaceVSAvoidoil supply
Core Design Contradiction:
Volume of stationary objectVSEase of operation

Solution Approach 1:

The drive unit serves as an intermediary component between the oil reservoir and the compression unit. Oil is supplied from the oil reservoir, passes through the drive unit which acts as a mediator, and then reaches the compression unit. This intermediary positioning allows the drive unit to facilitate oil distribution while maintaining the space-efficient configuration with the compression unit above the drive unit.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Reliability

If the rotation shaft is connected through the compression unit, then the point of applications of gas force and reaction force match, but additional lower frame is required

Engineering Contradiction:
Improveforce balanceVSAvoidstructural components
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The drive unit and compression unit are merged into a single integrated assembly where the rotation shaft connects both components. This merging eliminates the need for a separate lower frame structure, as the integrated design provides both the force balance alignment and structural support in one configuration, reducing overall device complexity while maintaining reliability.

Inventive Principle:
Principle #5Merging (Combining)

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 enhances oil separation efficiency by minimizing vibration, maintaining stability, and increasing centrifugal force, thereby improving the overall performance of the scroll compressor across various operating speeds.

Implementation Method 1

a centrifugal separator 620 that rotates together with the rotation shaft 230 and provides a centrifugal force for separating the oil from the refrigerant

Methodology Applied
Scientific EffectCentrifugal force: Centrifugal Force

Data Source

PatentEP3696416B1Rotary compressor with centrifugal oil separator
Publication Date: 2024.05.22 LG ELECTRONICS INC
  • EP3696416B1 patent drawingFigure 1~2
  • EP3696416B1 patent drawingFigure 3~3(b)
  • EP3696416B1 patent drawingFigure 4~4(e)

AI summary

Compressor including a casing (100) configured to include a discharge part (121) for discharging a refrigerant on one side and a reservoir space for storing oil, a driver (200) including a stator (210) coupled to an inner circumferential surface of the casing and generating a rotating magnetic field, and a rotor (220) accommodated in the stator and rotated by the rotating magnetic field, a rotation shaft (230) coupled to the rotor (220) and rotating together with the rotor, a compression unit (300) coupled to the rotation shaft (230) and lubricated with the oil, wherein the compression unit (300) compresses and discharges the refrigerant, and an oil-separator (600) disposed between the discharge part (121) and the driver (200) for separating the oil from the refrigerant to be guided to the discharge part , wherein the oil-separator includes a centrifugal separator (620) rotating together with the rotation shaft (230) to provide a centrifugal force for separating the oil from the refrigerant, and a coupler (610) for coupling the centrifugal separator (620) to the driver (200) such that the centrifugal separator and the rotation shaft (230) rotate together, and wherein the coupler is coupled to the rotor (220) or the rotation shaft (230).