Thermally Insulative Lining for Hermetic Compressor Exhaust Silencer

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional hermetic reciprocating compressors suffer from reduced thermodynamic efficiency due to heat dissipation from hot refrigerant during the compression phase and subsequent heat transfer affecting refrigerant density during the suction phase, leading to decreased performance.

Innovation Solution

A thermally insulative inner lining is used within the exhaust silencer to reduce heat transfer from the refrigerant to the metal case, utilizing materials with lower thermal conductivity, such as plastic or its derivatives, to enhance efficiency and damp acoustic vibrations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If the exhaust silencer is formed into the cylinder block with a refrigerant passage connecting the compression chamber and exhaust silencer, then a compact configuration is attained, but thermal energy of hot refrigerant is dissipated to the cylinder block during compression phase

Engineering Contradiction:
Improveconfiguration compactnessVSAvoidthermal energy dissipation
Core Design Contradiction:
Device complexityVSLoss of energy

Solution Approach 1:

A thermally insulative inner lining is introduced as an intermediary layer between the refrigerant and the metal cylinder block. This lining material (such as plastic or foam) has low thermal conductivity and prevents direct heat transfer from the hot refrigerant to the metal block, thereby reducing thermal energy dissipation while maintaining the compact integrated configuration

Inventive Principle:
Principle #24Intermediary (Mediator)

2Device complexity

If the exhaust silencer is formed into the cylinder block, then a compact configuration is attained, but heat dissipated to the cylinder block is transferred to the refrigerant during suction phase, decreasing refrigerant density

Engineering Contradiction:
Improveconfiguration compactnessVSAvoidrefrigerant density
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The thermally insulative inner lining acts as a thermal barrier that prevents heat stored in the cylinder block from transferring to the refrigerant during the suction phase. This maintains the refrigerant density and ensures reliable compressor operation while preserving the compact integrated design

Inventive Principle:
Principle #24Intermediary (Mediator)

3Loss of energy

If a thermally insulative inner lining is added inside the exhaust silencer, then heat transfer from refrigerant to metal case is reduced, but device complexity increases

Engineering Contradiction:
Improveheat transfer reductionVSAvoidstructure complexity
Core Design Contradiction:
Loss of energyVSDevice complexity

Solution Approach 1:

The inner lining is implemented as a thin-walled hollow capsule structure that conformally fits within the exhaust silencer cavity. This thin-film approach provides effective thermal insulation while minimizing the increase in structural complexity and maintaining a compact overall design

Inventive Principle:
Principle #30Flexible shells and thin films

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 thermally insulative inner lining prevents thermal energy dissipation, maintaining refrigerant density and improving the thermodynamic efficiency of the compressor.

Implementation Method 1

the thermally insulative inner lining (1) comprises a main body (10) made of a thermally insulative material

Methodology Applied
Scientific EffectThermal insulation: Thermal Insulation

Implementation Method 2

an hollow portion (13) which is formed into the main body (10) to acoustically damp the exhaust refrigerant

Methodology Applied
Scientific EffectAcoustic damping: Damping

Data Source

PatentEP3126674B1Thermally insulative inner lining for use in an exhaust silencer of a hermetic reciprocating compressor
Publication Date: 2019.08.07 ARCELIK AS
  • EP3126674B1 patent drawingFigure 1
  • EP3126674B1 patent drawingFigure 2
  • EP3126674B1 patent drawingFigure 3

AI summary

A hermetic reciprocating compressor (3) comprising: a cylinder block (4) which includes a compression chamber (5) for compressing a refrigerant; an exhaust silencer (2) which includes a cavity (6) formed into the cylinder block (4); an intake port (7) and an exhaust port (8) which respectively open into the cavity (6), wherein the compression chamber (5) and the intake port (7) are in fluid communication through an exhaust refrigerant passage (9). The exhaust silencer (2) comprises a heat-insulating inner lining (1) which form-fittingly matches an inner surface of the cavity (6).