Adjustable Scroll Pump Radial Clearance Dynamics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Miniaturization of scroll pumps leads to increased internal leakage, which negatively impacts the achievable ultimate pressure, making it challenging to maintain a suitable radial clearance that prevents seizing while ensuring acceptable performance, especially in pumps with capacities below a certain threshold.
Innovation Solution
The scroll pump design allows for adjustable radial positioning of the orbiting scroll relative to the fixed scroll, enabling a near-constant radial clearance through movable bearings and a flexible bearing carrier, which optimizes the radial clearance and improves performance by allowing a smaller clearance without seizing, including improved ultimate pressure and power efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the pump capacity is reduced for miniaturization, then the size of the scroll pump is reduced, but internal leakage increases and ultimate pressure deteriorates
Solution Approach 1:
The patent applies dynamics by making the radial clearance between scrolls adjustable during operation. The orbiting scroll's radial position can be changed to optimize clearance, transforming a static clearance design into a dynamic one that adapts to different operating conditions, thereby resolving the contradiction between miniaturization and maintaining ultimate pressure performance
Solution Approach 2:
The patent changes the parameter of radial clearance from a fixed value to an adjustable value. By enabling variation in the radial clearance parameter through movable bearings and flexible bearing carriers, the system can optimize performance across different pump capacities, addressing the deterioration of ultimate pressure in miniaturized pumps
2Reliability
If the radial clearance between scrolls is reduced to improve performance, then ultimate pressure improves, but the risk of seizing increases
Solution Approach 1:
The patent uses dynamic adjustment of radial clearance through movable bearings that can shift position. This allows the system to maintain a near-constant optimized clearance that prevents seizing while maximizing ultimate pressure performance, resolving the contradiction between reduced clearance for better pressure and increased seizing risk
Solution Approach 2:
The patent introduces flexible bearing carriers as intermediary elements between the fixed and orbiting scrolls. These carriers accommodate thermal expansion and manufacturing tolerances while maintaining the desired radial clearance, acting as a buffer that prevents seizing while preserving the performance benefits of small clearance
3Productivity
If the radial clearance is reduced below a certain value, then performance improves, but the pump may seize
Solution Approach 1:
The patent implements dynamic clearance control where the radial gap between scrolls can be adjusted during operation. This dynamic capability allows the system to find and maintain the optimal clearance value that maximizes productivity while preventing seizing, rather than being constrained by a fixed clearance design
Solution Approach 2:
The patent enables change in the radial clearance parameter from a fixed value determined by manufacturing tolerances to an adjustable parameter that can be optimized for each operating condition. This parameter change allows achieving better performance without crossing into the seizing risk zone
Data Source
AI summary
The Invention provides a scroll pump comprising an orbiting scroll and a fixed scroll, wherein the orbital axis of the orbiting scroll is movable in a radial direction relative to the fixed scroll while the orbiting scroll is orbiting about its orbital axis, or wherein the fixed scroll is movable relative to the orbiting scroll in a radial direction while the orbiting scroll is orbiting about its orbital axis.