Linear Compressor Oil Venting to Reduce Friction and Vapor Lock
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Solution Overview
Problem
Linear compressors in refrigeration systems face issues with friction between the piston and the chamber wall, leading to efficiency losses and lubrication oil degradation due to refrigerant outgassing, which prevents effective lubrication of moving parts.
Innovation Solution
A sealed system design incorporating a linear compressor with a casing, piston, shell, condenser, oil outlet conduit, and heat exchanger, featuring an oil reservoir, oil exhaust, and gas vent to manage lubrication oil and refrigerant vapor, reducing friction and ensuring adequate lubrication by directing lubrication oil to the piston and removing refrigerant vapor.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a linear compressor is used to compress refrigerant, then the compressor structure is simplified and efficiency is improved, but friction between the piston and chamber wall increases leading to energy losses and lubrication degradation
Solution Approach 1:
The patent extracts and removes refrigerant vapor from the lubrication oil through a dedicated gas vent passage, preventing vapor lock and reducing friction between the piston and chamber wall. This separation of refrigerant vapor from the lubrication system directly addresses the friction losses problem while maintaining the efficiency benefits of the linear compressor design
Solution Approach 2:
The patent introduces an intermediary gas vent passage that facilitates the removal of refrigerant vapor from the lubrication oil. This intermediary structure enables the separation function without requiring complex additional components, thus reducing friction losses while preserving compressor efficiency
2Temperature
If refrigerant is compressed in the linear compressor, then cooling performance is achieved, but refrigerant outgassing prevents lubrication oil from flowing properly causing lack of lubrication
Solution Approach 1:
The patent segments the lubrication system into separate pathways for oil flow and refrigerant vapor removal. The gas vent passage is positioned to specifically target and remove refrigerant vapor from the lubrication oil, ensuring that lubrication reliability is maintained independent of the refrigeration function. This segmentation allows the compressor to achieve cooling performance while preventing lubrication failures
Solution Approach 2:
The patent replaces the traditional mechanical centrifugal oil pump system with a passive gas vent passage that uses pressure differential and buoyancy to remove refrigerant vapor. This substitution eliminates the complexity of mechanical oil pumping while ensuring reliable lubrication by continuously removing vapor that would otherwise interfere with oil flow
3Power
If the piston slides within the chamber during compression, then refrigerant compression is achieved, but friction and heat generation reduce lubrication oil effectiveness
Solution Approach 1:
The patent extracts heat from the lubrication system by removing refrigerant vapor that carries excess heat generated during compression. The gas vent passage enables continuous removal of hot vapor, preventing heat accumulation that would otherwise degrade lubrication oil effectiveness while maintaining the power needed for refrigerant compression
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 solution enhances the efficiency of the linear compressor by reducing friction and preventing lubrication failures, improving the compressor's operational longevity and performance by effectively cooling and distributing lubrication oil.
Implementation Method 1
The heat exchanger may be spaced apart from the internal volume in fluid communication with the oil outlet conduit to receive lubrication oil from the linear compressor
Implementation Method 2
The gas vent may extend from the oil reservoir to the internal volume in fluid parallel with the oil exhaust
Implementation Method 3
The oil reservoir may be positioned radially outward from the chamber of the cylinder assembly to selectively direct lubrication oil thereto
Data Source
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AI summary
Disclosed is a refrigeration system, comprising a linear compressor (64), a casing (302), and a condenser (66), wherein the linear compressor (64) can comprise a shell (308) and a piston (316); the shell (308) can extend axially from a first end portion (304) to a second end portion (306); the shell (308) comprises an air cylinder assembly (310) for defining a cavity (312) approaching the second end portion (306), and the piston (316) can be received in the cavity (312) of the air cylinder assembly (310) in a slidable manner; the shell (308) further defines an oil reservoir (386), an oil drain (390) and a vent (392); the casing (302) defines an interior volume (303) enclosing the linear compressor (64) and lubricating oil therein; and on the downstream side, the condenser (66) is in fluid communication with the linear compressor (64) to receive a compressed refrigerant therefrom. The linear compressor can limit friction or contact between the piston and an air cylinder wall during operation.