Reflux check valve
US4216791A · kind A · utility
1Cited by
3References
5Claims
0Family size
Inventor
Key dates
| Filing date | Jan 30, 1978 |
| Grant date | Aug 12, 1980 |
| Priority date | — |
| Expiry date | Jan 30, 1998 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/87917
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A check valve is inserted in a tubing such as a catheter for transmission of dry gas such as to the bladder of a person. It prevents the flow of liquid such as urine through it by means of a plug of a foam material which permits the flow of dry gas through it and past end discs of a material which expands in the presence of liquid to plug up the passageway of the valve thereby preventing liquid from flowing through it.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.