Sewer relief valve
US4475571A · kind A · utility
22Cited by
19References
28Claims
0Family size
Inventors
Key dates
| Filing date | Jun 7, 1983 |
| Grant date | Oct 9, 1984 |
| Priority date | — |
| Expiry date | Jun 7, 2003 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/863
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An improved sewer relief valve which is vandal-proof and automatically opens responsive to a back flow of sewage and drain water within a plumbing system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.