Piston having two piston rings
US11162585B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 31, 2019 |
| Grant date | Nov 2, 2021 |
| Priority date | — |
| Expiry date | Jan 31, 2039 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16J9/206
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A piston assembly for an internal combustion engine includes a cylinder bore and a piston having exactly two ring grooves, a scraper ring positioned in the upper ring groove, and an oil control ring positioned in the lower ring groove. A constant twist occurs in the scraper ring about a rotational center of the cross-section, the constant twist occurring at each cross-sectional location of the scraper ring about the circumference of the ring and between adjacent free ends of the ring. The oil control ring can be of a multi-segmented U-flex design, with a coil spring mounted in a channel thereof. The combination of the two rings leads to improved sealing and oil control so that the piston can be manufactured with only two rings, thus reducing overall weight and cost.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.