Scroll Compressor Auxiliary Discharge Port Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional scroll compressors experience efficiency reduction at partial or low load conditions due to over-compression of refrigerant in the indirect pocket, which is costly to address through existing solutions that modify the spiral wraps or create complex dummy port recesses.
Innovation Solution
Incorporating an auxiliary discharge port on the fixed end plate near the outer wall side of the fixed spiral wrap, which communicates with the indirect pocket during orbiting movement, increasing the flow section and reducing over-compression, and manufactured through simple drilling processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the inner end tips of the fixed and orbiting spiral wraps are modified to achieve similar flow conditions, then the over-compression problem is solved, but the manufacturing complexity and cost increase
Solution Approach 1:
An auxiliary discharge port is introduced as an intermediary element to mediate the discharge process. This port provides an additional flow path that balances the discharge timing between direct and indirect pockets, eliminating over-compression without requiring modification of the spiral wraps themselves.
Solution Approach 2:
The discharge process is segmented into two separate paths: one through the central main discharge port for the direct pocket, and another through the auxiliary discharge port for the indirect pocket. This segmentation allows independent optimization of each discharge path, achieving balanced flow conditions without complex spiral wrap modifications.
2Loss of energy
If a dummy port recess is formed in the orbiting end plate to control discharge timing, then the indirect pocket discharge is improved, but the manufacturing cost increases
Solution Approach 1:
The auxiliary discharge port serves as a simple intermediary structure that can be easily manufactured by drilling or punching operations. It provides the necessary flow control function without requiring complex dummy port recesses with adapted shapes to match spiral patterns.
Solution Approach 2:
Instead of modifying the orbiting end plate with complex dummy port recesses, the invention inverts the approach by adding a simple auxiliary discharge port to the fixed end plate. This reversed approach achieves the same flow control objective with much simpler manufacturing.
3Loss of energy
If the available flow section from the indirect pocket increases slower than from the direct pocket, then over-compression occurs, but the discharge flow control becomes complex
Solution Approach 1:
The discharge flow control is segmented into two independent paths with separate discharge ports. The auxiliary discharge port specifically handles the indirect pocket discharge, allowing independent optimization of flow characteristics for each pocket without requiring complex coordinated control mechanisms.
Solution Approach 2:
The auxiliary discharge port acts as an intermediary that specifically addresses the indirect pocket discharge timing issue. It provides a dedicated flow path that balances the discharge characteristics between direct and indirect pockets, eliminating over-compression through simple geometric design rather than complex control mechanisms.
Data Source
AI summary
The scroll compressor comprises a fixed scroll element comprising a fixed end plate (13) and a fixed spiral wrap (14); an orbiting scroll element comprising an orbiting end plate and an orbiting spiral wrap (16), the fixed and orbiting spiral wraps (14, 16) being intermeshed with each other to define pairs of compression pockets, a radial inner pair of compression pockets comprising a direct pocket (17.1) and an indirect pocket (17.2); a central main discharge port (18) formed in the fixed end plate (13) and configured to communicate the direct pocket (17.1) with a discharge pressure volume; and an auxiliary discharge port (26) formed in the fixed end plate (13) at a position close to an outer wall side (14.2) of the fixed spiral wrap (14) and adjacent the inner end (14.4) of the fixed spiral wrap (14). The auxiliary discharge port (26), during orbiting movement of the orbiting scroll element (12), is at least partially uncovered by the orbiting spiral wrap (16) to communicate the indirect pocket (17.2) with the discharge pressure volume.