Scroll Compressor Oil Passage Layout to Prevent Chamber Backflow
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Solution Overview
Problem
Existing scroll compressors face issues such as compression loss, refrigerant backflow between compression chambers, unstable orbiting scroll behavior, and reduced reliability due to simultaneous opening of oil supply passages, which are exacerbated during low-pressure ratio operations.
Innovation Solution
The design includes separate first and second oil supply passages that communicate with distinct compression chambers, with the first oil supply passage being guided inwardly towards the center of the orbiting scroll, minimizing overlap and ensuring stable operation by controlling the crank angle openings, and securing a coupling length for blocking bolts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If separate first and second oil supply passages are provided to supply oil to first and second compression chambers respectively, then oil supply reliability is improved, but refrigerant backflow between compression chambers occurs due to overlapping passages
Solution Approach 1:
The oil supply system is segmented into separate first and second oil supply passages for the first and second compression chambers respectively. Each passage is independently positioned and sized to prevent overlap, eliminating refrigerant backflow while maintaining reliable oil supply to both chambers through dedicated pathways.
2Stability of the object's composition
If oil supply holes are positioned far from the rotating shaft center to reduce overturning moment, then orbiting scroll stability is improved, but compression chamber oil supply efficiency decreases
Solution Approach 1:
The oil supply passages are locally optimized with different positioning strategies: the first oil supply passage is positioned to minimize overturning moment on the orbiting scroll, while the second oil supply passage is positioned to maximize oil supply efficiency to the second compression chamber. Each passage is sized and positioned according to its specific functional requirements, achieving both stability and efficiency.
3Adaptability or versatility
If overlapping oil supply passages are used to ensure oil supply during low-pressure ratio operation, then oil supply coverage is improved, but compression loss increases due to pressure difference equalization
Solution Approach 1:
The oil supply system is divided into separate first and second oil supply passages that do not overlap in their pathways. This segmentation prevents pressure equalization between the first and second compression chambers, eliminating compression loss while still providing comprehensive oil supply coverage to both chambers through their respective dedicated passages.
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 reduces compression loss, prevents refrigerant backflow, stabilizes the orbiting scroll, and enhances reliability by minimizing overlap and securing a coupling length for blocking bolts, thereby improving overall compression efficiency.
Implementation Method 1
An oil supplying method using the differential pressure can eliminate a component such as an oil pump, thereby reducing a fabricating cost and effectively supplying oil to the compression unit.
Data Source
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AI summary
A scroll compressor according to the present disclosure includes a first oil supply passage communicating with a first compression chamber formed between an inner circumferential surface of a fixed wrap and an outer circumferential surface of an orbiting wrap, and a second oil supply passage separated from the first oil supply passage and communicating with a second compression chamber formed between an outer circumferential surface of the fixed wrap and an inner circumferential surface of the orbiting wrap, wherein the first oil supply passage includes an oil supply guide portion provided in a thrust surface of the fixed scroll in contact with the orbiting scroll to define a part of the first oil supply passage, whereby communication between the first and second compression chambers can be prevented, thereby suppressing leakage between the compression chambers, stabilizing behavior of the orbiting scroll, and facilitating formation of the orbiting scroll.