Oil Separator Float Venting for Pressure-Breakage Prevention

Solution Overview

Problem

Conventional oil separators in refrigerating cycle apparatuses face issues with float breakage due to high pressure changes, leading to inefficient oil return and increased manufacturing costs, as well as potential compressor burning and cooling errors.

Innovation Solution

The oil separator incorporates a float with equalizing means that allows communication between the interior and exterior spaces above the oil level, eliminating pressure differences and preventing float breakage, while also reducing the complexity and cost of the design.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the float is made to withstand high pressure changes through welding two metal hemispheres, then the float strength is improved, but the manufacturing cost increases and the risk of metal fatigue breaks

Engineering Contradiction:

Improvefloat strengthVSAvoidmanufacturing cost

Core Design Contradiction:

StrengthVSEase of manufacture

Solution Approach 1:

The patent replaces the expensive, complex welded metal float with a simple, inexpensive polyethylene resin float. The float is designed to be replaceable rather than durable, eliminating metal fatigue concerns while significantly reducing manufacturing cost. The simple geometry requires no welding or complex assembly.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

2Strength

If the float is made to withstand high pressure changes through welding two metal hemispheres, then the float strength is improved, but the device complexity increases

Engineering Contradiction:

Improvefloat strengthVSAvoidfloat structure complexity

Core Design Contradiction:

StrengthVSDevice complexity

Solution Approach 1:

The patent replaces the expensive, complex welded metal float with a simple, inexpensive polyethylene resin float. The float is designed to be replaceable rather than durable, eliminating metal fatigue concerns while significantly reducing manufacturing cost. The simple geometry requires no welding or complex assembly.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

3Strength

If the float is made with complex welding of metal hemispheres, then the float can withstand pressure, but the reliability decreases due to metal fatigue and breakage

Engineering Contradiction:

Improvefloat pressure resistanceVSAvoidfloat reliability

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

The patent replaces the expensive, complex welded metal float with a simple, inexpensive polyethylene resin float. The float is designed to be replaceable rather than durable, eliminating metal fatigue concerns while significantly reducing manufacturing cost. The simple geometry requires no welding or complex assembly.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The patent changes the material parameter from metal to polyethylene resin, and changes the design parameter from pressure-resistant to replaceable. This parameter change eliminates metal fatigue and breakage issues, improving reliability through simplicity rather than strength.

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

This configuration effectively prevents float breakage and ensures reliable oil return, reducing the risk of compressor burning and cooling errors while significantly lowering manufacturing costs.

Implementation Method 1

a float (24) having a hollow (24H) therein that is held vertically movably in the tank (21), the float (24) moving up and down with a change of an oil level in the tank (21)

Methodology Applied

Scientific EffectBuoyancy: Archimedes' Principle (Buoyancy)

Implementation Method 2

The float (24) includes equalizing means (32) having one end that opens at a bottom part in the float (24) and the other end that opens outside of the float (24) and above the oil level in the tank (21)

Methodology Applied

Scientific EffectPressure equalization: Pascal's Law

Data Source

PatentUS9068769B2Oil separator and refrigerating cycle apparatus using the same

Publication Date: 2015.06.30 PANASONIC HEALTHCARE HLDG CO LTD

AI summary

An oil separator capable of preventing breakage in a float with an extremely simple configuration is provided. An oil separator is to separate oil in a refrigerant that is discharged from a compressor and return the oil to the compressor. The oil separator includes: a tank, into which a refrigerant discharged from the compressor flows; a float having a hollow therein that is held vertically movably in the tank, the float moving up and down with a change of an oil level in the tank; and a needle valve to return oil in the tank to the compressor in accordance with up/down movement of the float. The float includes an equalizing tube having a lower end that opens at a bottom part in the float and an upper end that opens outside of the float and above the oil level in the tank.