Piston rings and their manufacture
US4655983A · kind A · utility
4Cited by
9References
3Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Aug 12, 1985 |
| Grant date | Apr 7, 1987 |
| Priority date | — |
| Expiry date | Aug 12, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49277
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A piston ring is formed by annular upper and lower parts which contact one another at respective surfaces normal to the axis of the piston ring. The parts can be injection moulded from thermoplastics materials with the parts themselves having no re-entrant portions, so allowing quick and easy manufacture, but with the parts together defining re-entrant portions such as a spring-receiving recess at the inward side of the ring or a pair of spaced oil control rails at the outward side of the ring.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.