Holding tank vacuum relief
US6234197A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 23, 1996 |
| Grant date | May 22, 2001 |
| Priority date | — |
| Expiry date | Sep 23, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/7897
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A plastic sewage holding tank in a boat, associated with a toilet, includes a vent check valve for providing vacuum relief. By mounting the vent check valve in the top of the tank, when the tank is being emptied by rapid pumpout implosion or other damage to the tank is prevented. The vent check valve may include a valve body with an interior surface mounting a quad sealing ring, with a valve element guided for reciprocal movement between a sealing position where an axially elongated substantially cylindrical peripheral surface of the valve element engages the quad ring, to an open position where the valve element is moved against spring bias away from the valve body. A spider, with a collar for guiding a shaft portion of the valve element, may mount a coil spring to provide a biasing action.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.