Scroll Compressor Discharge Port Noise Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing scroll compressor designs face challenges in reducing noise due to pressure fluctuations in the central compression chamber, as techniques like decreasing the discharge port diameter or forming it in an oval shape either increase pressure loss or complicate machining, making them impractical.
Innovation Solution
A scroll compressor with a deformed elongated hole-shaped discharge port, featuring circular holes at both ends connected by surfaces with a width smaller than the hole diameters, which delays backflow and reduces pressure fluctuations, while being easier to machine using drilling and end-milling techniques.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If the discharge port diameter is decreased to delay backflow and reduce noise, then noise from pressure fluctuations is reduced, but the cross-sectional area of the flow channel is decreased, increasing pressure loss and input power
Solution Approach 1:
The discharge port is divided into multiple segments: a central circular hole and multiple arc-shaped holes arranged around it. This segmentation allows the total cross-sectional area to be maintained (reducing pressure loss) while the individual hole configurations delay backflow timing (reducing noise). The distributed arrangement of holes creates multiple flow paths that prevent simultaneous backflow, thereby reducing pressure fluctuations.
Solution Approach 2:
The arc-shaped holes are positioned asymmetrically around the central hole at specific angular intervals. This asymmetric arrangement ensures that backflow through different holes occurs at staggered times, preventing synchronized pressure fluctuations. The asymmetric geometry also optimizes the flow distribution while maintaining sufficient total cross-sectional area.
2Object-affected harmful factors
If the discharge port is formed in an oval shape to provide sufficient cross-sectional area and delay backflow, then noise is reduced, but machining time increases significantly, decreasing production efficiency
Solution Approach 1:
Instead of machining a complex oval shape, the discharge port is segmented into multiple simple circular and arc-shaped holes. These can be drilled and milled using standard machining operations, avoiding the time-consuming process of creating an oval contour. The segmented design achieves the same backflow delay effect as an oval shape while being much more efficient to manufacture.
Solution Approach 2:
The arc-shaped holes are essentially copies of circular hole geometry, which can be produced using standard drilling and milling tools. This copying of simple geometric forms avoids the need for specialized oval-shaped tooling or complex multi-axis machining operations, significantly reducing machining time while maintaining the desired flow characteristics.
3Object-affected harmful factors
If the discharge port is formed in a polygonal shape to delay backflow, then noise is reduced, but machining becomes practically impossible
Solution Approach 1:
Instead of trying to machine complex polygonal shapes directly, the invention inverts the approach by using multiple simple circular and arc-shaped holes that collectively achieve the same backflow delay effect. These inverted-simple-geometry elements are much easier to machine using conventional tools and processes.
Solution Approach 2:
The design uses replicated circular and arc-shaped hole patterns that can be produced by copying standard tool paths. This copying approach with simple geometries avoids the need for complex polygonal machining operations, making the discharge port practical to manufacture while maintaining noise reduction performance.
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
Disclosed is a scroll compressor in which a compression chamber (24) is formed by engaging a pair of fixed scroll and a rotating scroll in each other, the fixed scroll and the rotating scroll respectively comprising an end plate and a spiral wrap (18B, 19B) erected on the end plate, and a discharge port (25) to discharge a fluid compressed in the compression chamber (24) is provided in the center section of the fixed scroll. The discharge port (25) has a shape of a deformed long hole in which both of the ends are circular holes (25A and 25B), which are combined by two surfaces (25C, 25D) having a width (W) smaller than the hole diameter (D) of the circular holes.