Scroll Compressor Clearance Design for Thermal Expansion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The scroll compression mechanism experiences reliability issues due to thermal expansion and pressure deformation, leading to potential contact between the stationary and orbiting scrolls when using high-pressure refrigerants like CO2, which can cause damage and efficiency losses.
Innovation Solution
The compressor design features a scroll compression mechanism with larger clearances between the tip portions of the stationary and orbiting scrolls further outward from their support positions, preventing contact and maintaining efficiency by adjusting the height of the scroll structures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the clearance between the stationary scroll and orbiting scroll is increased to prevent contact, then reliability is improved, but leakage gap increases and efficiency deteriorates
Solution Approach 1:
The patent applies local quality by making the clearance between the stationary scroll and orbiting scroll non-uniform. Specifically, the clearance is made larger at the outer circumferential portion where thermal expansion and pressure deformation occur, and smaller at the inner circumferential portion. This localized adjustment prevents contact at critical areas while minimizing leakage gaps, thus resolving the contradiction between reliability and efficiency.
2Stress or pressure
If the volume of high-pressure portion is decreased to reduce pressure magnitude, then pressure deformation is reduced, but efficiency deteriorates due to increased discharge pulsation and pressure loss
Solution Approach 1:
The patent applies local quality by adjusting the volume distribution of the high-pressure portion. The compression chamber volume is designed to be larger at the outer circumferential portion where pressure deformation occurs, and smaller at the inner circumferential portion. This localized volume adjustment reduces pressure deformation without significantly increasing overall discharge pulsation, thus resolving the contradiction between pressure control and efficiency.
Data Source
Figure 1
Figure 2~3
AI summary
A scroll compressor including a stationary scroll (41) having a spiral-shaped stationary spiral structure (47) that is vertically provided on one surface of a stationary end plate (45) secured at a stationary-side support position (F) positioned at an outer circumference; and an orbiting scroll (43) having an orbiting end plate (51) that is provided with a spiral-shaped orbiting spiral structure (53) vertically on one surface thereof to be meshed with the stationary end plate (45), and that is supported at a position closer to a center than the stationary-side support position (F) in a manner that allows a revolving motion; wherein, for at least one of a clearance between a tip portion of the stationary spiral structure (47) and the orbiting end plate (51) and a clearance between the orbiting spiral structure (53) and the stationary end plate (45), the clearance (S1) at a side further outward than the orbiting-side support position (C) is made larger than the clearance (S2) at the center side.