Linear Compressor Intake Muffler Shape for Lower Wind Loss

Solution Overview

Problem

Existing linear compressors experience significant wind loss due to pressure resistance of refrigerant during piston and intake muffler reciprocation, leading to inefficiencies and noise, with high drag coefficients in current intake muffler designs.

Innovation Solution

The introduction of a third muffler with a streamlined portion of decreasing diameter in the axial direction within the linear compressor, which reduces wind loss by optimizing the flow passage and drag coefficients.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If a traditional intake muffler design is used in a linear compressor, then the structure is simple and easy to manufacture, but the drag coefficient is high causing significant wind loss and noise during piston reciprocation

Engineering Contradiction:

Improvewind lossVSAvoidmuffler structure

Core Design Contradiction:

Loss of energyVSDevice complexity

Solution Approach 1:

The intake muffler is divided into three separate mufflers (first, second, and third mufflers) that are coupled together. Each muffler has a specific function: the first muffler reduces noise from the piston, the second muffler further reduces noise and begins to address flow resistance, and the third muffler with its streamlined portion significantly reduces the drag coefficient. This segmentation allows each component to be optimized for its specific function while collectively solving the overall problem of wind loss and noise.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The third muffler incorporates a streamlined portion with a curved surface that gradually decreases in diameter from the upstream end to the downstream end. This curved, aerodynamic shape reduces turbulence and pressure resistance of the refrigerant flow, thereby significantly lowering the drag coefficient compared to traditional straight-cylindrical muffler designs. The streamlined geometry allows refrigerant to flow more smoothly through the muffler during piston reciprocation.

Inventive Principle:

Principle #14Spheroidality (Curvature)

2Productivity

If the third muffler with streamlined portion is added to reduce drag coefficient, then wind loss is reduced by 48%, but the device complexity increases

Engineering Contradiction:

Improvecompression efficiencyVSAvoidmuffler structure

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The intake muffler is divided into three separate mufflers (first, second, and third mufflers) that are coupled together. Each muffler has a specific function: the first muffler reduces noise from the piston, the second muffler further reduces noise and begins to address flow resistance, and the third muffler with its streamlined portion significantly reduces the drag coefficient. This segmentation allows each component to be optimized for its specific function while collectively solving the overall problem of wind loss and noise.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The third muffler incorporates a streamlined portion with a curved surface that gradually decreases in diameter from the upstream end to the downstream end. This curved, aerodynamic shape reduces turbulence and pressure resistance of the refrigerant flow, thereby significantly lowering the drag coefficient compared to traditional straight-cylindrical muffler designs. The streamlined geometry allows refrigerant to flow more smoothly through the muffler during piston reciprocation.

Inventive Principle:

Principle #14Spheroidality (Curvature)

Data Source

PatentUS11788523B2Linear compressor

Publication Date: 2023.10.17 LG ELECTRONICS INC

AI summary

A linear compressor includes: a shell including an intake pipe configured to suction a refrigerant, a piston configured to reciprocate in an axial direction and including a piston body, and an intake muffler coupled to the piston and configured to flow the refrigerant into the piston body and reduce a noise from the refrigerant. The intake muffler includes a first muffler disposed inside the piston body, a second muffler disposed at a rear side of the first muffler and in fluid communication with the first muffler, and a third muffler including a third muffler body having a cylindrical shape with an empty interior and configured to accommodate a portion of a rear end of the first muffler and the second muffler in the third muffler body. The third muffler body includes a streamlined portion having diameters reduced toward a rear side of the third muffler body in the axial direction.