Compressor Piston Suction Port Geometry for Miniaturized Compression

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional linear compressors face reduced compression efficiency due to decreased cross-sectional area of suction ports and increased stiffness of suction valves as the piston diameter miniaturizes, leading to poor response characteristics and leakage issues.

Innovation Solution

The design of the piston includes a cylindrical slider with a head having an inner and outer body, where the suction port is formed between them, with bridges connecting the bodies and a suction valve that can open and close the port, optimizing the shape to increase the effective cross-sectional area and reduce flow path resistance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If the piston diameter is miniaturized, then the compressor size is reduced, but the cross-sectional area of the suction port decreases and the suction valve stiffness increases

Engineering Contradiction:
Improvecompressor sizeVSAvoidresponse characteristics
Core Design Contradiction:
Volume of moving objectVSReliability

Solution Approach 1:

The suction port is redesigned from a conventional circular cross-section to an elliptical cross-section. This dimensional change in shape allows the effective cross-sectional area to be increased without increasing the piston diameter, thereby maintaining the suction port area despite miniaturization of the compressor.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The shape parameters of the suction port are changed from a circular geometry to an elliptical geometry with optimized major and minor axes. This parameter change increases the effective cross-sectional area (Ss) while keeping the piston diameter small, directly addressing the contradiction between miniaturization and maintaining suction performance.

Inventive Principle:
Principle #35Parameter changes

2Strength

If the opening part length is shortened, then the suction valve stiffness increases, but the response characteristics deteriorate

Engineering Contradiction:
Improvevalve stiffnessVSAvoidresponse characteristics
Core Design Contradiction:
StrengthVSSpeed

Solution Approach 1:

The length parameter of the opening part is optimized to a specific range (0.5-2.0 times the piston diameter) to achieve the desired balance between stiffness and response characteristics. This parameter optimization allows the valve to maintain adequate stiffness while preserving sufficient response capability.

Inventive Principle:
Principle #35Parameter changes

3Volume of moving object

If the cross-sectional area of suction ports decreases, then the piston size is reduced, but the discharge flow rate decreases

Engineering Contradiction:
Improvepiston sizeVSAvoiddischarge flow rate
Core Design Contradiction:
Volume of moving objectVSProductivity

Solution Approach 1:

The suction port cross-section is changed from circular to elliptical, utilizing the dimensional advantage of the ellipse to provide a larger effective area (Ss) within the constrained piston diameter. This shape transformation directly increases the discharge flow rate capability without increasing piston size.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The elliptical cross-section with optimized curvature ratios (major axis to minor axis ratio between 1.2-2.0) provides improved flow characteristics and larger effective area compared to a circular section of the same bounding diameter, thereby maintaining productivity during miniaturization.

Inventive Principle:
Principle #14Spheroidality (Curvature)

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 the compression efficiency, improves the durability of the suction valve, and prevents refrigerant leakage, while maintaining the miniaturized piston size by optimizing the suction port shape and valve operation.

Implementation Method 1

a suction valve configured to be coupled to the front of the head and to be capable of opening and closing the suction port

Methodology Applied
Scientific EffectElastic deformation: Elasticity

Implementation Method 2

a compressor which compresses and discharges refrigerant suctioned into a cylinder

Methodology Applied
Scientific EffectCompression: Compression

Data Source

PatentEP3800352B1Piston for compressor and compressor having same
Publication Date: 2021.12.22 LG ELECTRONICS INC
  • EP3800352B1 patent drawingFigure 1
  • EP3800352B1 patent drawingFigure 2
  • EP3800352B1 patent drawingFigure 3~4

AI summary

A piston (200) for a compressor (100) and a compressor (100) including the same are disclosed. The piston (200) compresses and discharges refrigerant suctioned into a cylinder (140), and the piston (200) includes a cylindrical slider (220) having an outer diameter corresponding to an inner diameter of the cylinder (140) and forming a suction space (102) in which the refrigerant suctioned in the cylinder (140) is received; and a head (210) which is configured to be coupled to the slider (220), in which a compression space (103) is provided in the front and a suction space (102) is provided in the rear, and in which a suction port (214) communicating with the suction space (102) and the compression space (103) is formed, in which the head (210) includes an inner body (211) and an outer body (212) surrounding the inner body (211), and the suction port (214) is formed between the inner body (211) and the outer body (212).