Friction-Optimised Oil Scraper Ring with Helical Surface
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing oil scraper rings for piston engines experience high friction, which affects their efficiency and longevity due to the presence of two scraper webs and traditional pressure distribution methods.
Innovation Solution
A piston ring design featuring a single circumferential oil scraper web with a helical running surface and a diamond-like carbon coating, along with a hose spring arrangement, to reduce friction and enhance lubricity, while maintaining or exceeding the tangential force of conventional rings with two scraper webs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If two scraper webs are used in conventional oil scraper rings, then oil scraping capability is improved, but friction increases
Solution Approach 1:
The patent extracts one scraper web from the conventional two-web design, leaving only a single scraper web. This reduction directly decreases the contact area with the cylinder wall, thereby reducing friction while maintaining adequate oil scraping capability through optimized geometry and coating
Solution Approach 2:
The patent applies local quality enhancement through diamond-like carbon coating on the running surface of the single scraper web. This coating provides extreme hardness and low friction properties locally at the contact zone, compensating for the reduced number of scraper webs and maintaining oil scraping effectiveness while minimizing friction
2Object-affected harmful factors
If a single scraper web is used, then friction is reduced, but oil scraping capability may deteriorate
Solution Approach 1:
The patent changes critical parameters of the single scraper web including: running surface radius of curvature (1/40 to 1/10 of height H), scraper web thickness (2-5 mm), and height (2.5-4 mm). These parameter optimizations enhance the scraping efficiency of the single web, compensating for the loss of the second web while maintaining low friction
Solution Approach 2:
The patent employs composite material structure by combining the base metal material with diamond-like carbon coating. This composite approach provides the mechanical strength needed for a single scraper web to handle oil scraping loads while the coating reduces friction and wear, ensuring both low friction and adequate scraping capability
3Object-affected harmful factors
If diamond-like carbon coating is applied, then lubricity and temperature resistance are improved, but manufacturing complexity increases
Solution Approach 1:
The patent specifies precise coating parameters: thickness (15-25 μm), hardness (4000-5000 HV 0.2), and temperature resistance (450-500°C). These controlled parameters ensure optimal performance while maintaining manufacturability through standardized coating processes
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
The design significantly reduces friction, improves lubricity, and extends the lifespan of the oil scraper ring by distributing pressure evenly and maintaining performance under high temperatures, even with a single scraper web, thus enhancing the overall efficiency of oil control in piston engines.
Implementation Method 1
a back of the scraper web is coated with an anti-wear coating... the oil scraper ring is provided with an anti-wear coating at least on the running surface... diamond-like carbon coating... amorphous, extremely hard carbon-based layer, which improves lubricity
Implementation Method 2
The running surface forms a helix or the wiper web runs helically, like a thread
Implementation Method 3
the oil scraper ring is provided with an expander... hose spring arrangement... the tangential force of the ring spring or hose spring is 52% to 68% of an oil control ring with two scraper webs
Data Source
Figure 1~2
Figure 3~4
AI summary
The invention relates to an oil scraper ring 2 for a piston of a piston engine, comprising a ring body 2 and a circumferential oil scraper rib 4, wherein the oil scraper ring 2 has a height H of 2 to 5 mm between an upper ring flank 8 and a lower ring flank 10. The running surface 6 of the scraper rib in a radial cross-section has a radius of curvature r which is between 1/40 and 1/10 of the height H, wherein the running surface forms a helix like a thread.