Scroll Compressor Oil Supply Across Sealing Part

Solution Overview

Problem

Existing scroll compressors face challenges in maintaining adequate lubricating oil supply at low rotational frequencies while avoiding excessive oil supply at high rotational frequencies, leading to inefficiencies and potential seizing of sliding parts.

Innovation Solution

The scroll compressor incorporates a dual lubrication system using small holes and grooves or a long hole, where lubricating oil is supplied from a high-pressure hydraulic chamber to a low-pressure back pressure chamber through differential pressure and orbital motion, allowing for controlled oil distribution based on rotational frequency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If only small holes are used for oil supply, then oil supply is controlled at high rotational frequency, but inadequate lubrication occurs at low rotational frequency

Engineering Contradiction:

Improvelubrication adequacyVSAvoidoperational efficiency

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The oil supply system is segmented into two distinct pathways: small holes for intermittent oil supply that moves across the sealing part with orbital motion, and grooves for continuous oil supply that maintains communication between chambers. This segmentation allows each pathway to serve different operational conditions - small holes prevent excessive oil supply at high speeds while grooves ensure adequate lubrication at low speeds.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system dynamically adapts oil supply based on rotational frequency. At low rotational frequencies, the continuous groove supply ensures adequate lubrication. At high rotational frequencies, the intermittent small hole supply prevents excessive oil from being agitated and discharged, automatically adjusting to operational conditions without external control.

Inventive Principle:

Principle #15Dynamics

2Loss of energy

If small holes are used to control oil supply, then excessive oil supply is prevented at high rotational frequency, but inadequate oil supply occurs at low rotational frequency

Engineering Contradiction:

Improveenergy efficiencyVSAvoidlubrication adequacy

Core Design Contradiction:

Loss of energyVSReliability

Solution Approach 1:

The oil supply system is segmented into two distinct pathways: small holes for intermittent oil supply that moves across the sealing part with orbital motion, and grooves for continuous oil supply that maintains communication between chambers. This segmentation allows each pathway to serve different operational conditions - small holes prevent excessive oil supply at high speeds while grooves ensure adequate lubrication at low speeds.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system dynamically adapts oil supply based on rotational frequency. At low rotational frequencies, the continuous groove supply ensures adequate lubrication. At high rotational frequencies, the intermittent small hole supply prevents excessive oil from being agitated and discharged, automatically adjusting to operational conditions without external control.

Inventive Principle:

Principle #15Dynamics

3Reliability

If lubricating oil is supplied to compression chamber, then scroll wrap lubrication is improved, but oil leakage increases

Engineering Contradiction:

Improvesealing performanceVSAvoidoil discharge

Core Design Contradiction:

ReliabilityVSLoss of substance

Solution Approach 1:

Different regions of the oil supply system have different characteristics - small holes provide localized intermittent supply near the sealing part for lubrication without excessive discharge, while grooves provide distributed continuous supply for reliable lubrication at low speeds. This local quality differentiation optimizes both sealing performance and minimizes oil discharge.

Inventive Principle:

Principle #3Local quality

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 solution ensures adequate lubrication across a wide range of rotational frequencies, improving efficiency and reliability by preventing both inadequate and excessive lubrication, reducing oil leakage, and maintaining optimal oil levels within the compressor.

Implementation Method 1

the small hole being caused, by the orbital motion of the orbiting scroll, to move across the sealing part

Methodology Applied

Scientific EffectOrbital motion:

Implementation Method 2

an oil supply passage formed in the orbiting scroll or the frame, the oil supply passage communicating between the high pressure hydraulic chamber and the back pressure chamber and causing oil in the high pressure hydraulic chamber to be supplied, by a differential pressure, to the back pressure chamber

Methodology Applied

Scientific EffectDifferential pressure: Pressure Gradient

Data Source

PatentUS8888475B2Scroll compressor with oil supply across a sealing part

Publication Date: 2014.11.18 HITACHI JOHNSON CONTROLS AIR CONDITIONING INC

AI summary

A scroll compressor is provided in which the amount of lubricant oil supply is appropriately controlled over a low to high rotational frequency range of the scroll compressor. The scroll compressor has an oil supply unit and an oil supply passage. The oil supply unit includes a small hole with a diameter not exceeding a seal ring width of the sealing part and a groove which are formed on the end plate of the boss portion on the back side of the orbiting scroll. As the orbiting scroll orbitally moves, oil in the high pressure hydraulic chamber pools in the small hole to be discharged, across the seal ring, into the back pressure chamber. The oil supply passage communicates between the high pressure hydraulic chamber and the back pressure chamber.