Cannula valve and seal system
US5458640A · kind A · utility
Inventor
Key dates
| Filing date | May 5, 1994 |
| Grant date | Oct 17, 1995 |
| Priority date | — |
| Expiry date | May 5, 2014 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B2090/062
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A surgical cannula includes a first valve seal for preventing insufflation gas from escaping from a patient's abdomen when an instrument is inserted or removed through the cannula. The valve seal has a V-shaped cross section and includes two opposing lips which face each other across a slit. Each lip has an internal and external edge separated by an intermediate section. The front surface of the first seal is relatively flat and has a width X. The preferred distance between the internal and external edges is preferably one-half X. This permits the internal edges to absorb the shock and damage from the introduction of a sharp instrument such as a trocar into the cannula without destroying the sealing capability of the external edges. A spring-loaded tubular member is located within the cannula housing and a reducer subassembly and is normally biased away from the interior surface of the first seal. When an instrument is introduced into the tubular member, it opens the first seal in such a way as to avoid damage to the first seal and, further, permits the withdrawal of tissues without interference. A second fixed or permanent seal located at the rear end of the tubular means also hel…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.