Vacuum powdered syringe
US5176642A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 11, 1991 |
| Grant date | Jan 5, 1993 |
| Priority date | — |
| Expiry date | Mar 11, 2011 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61M2005/3115
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A medical apparatus for injecting or withdrawing biological or therapeutic fluid includes a syringe body defining a syringe cavity into which fluids can be introduced or withdrawn by way of a fluid port and a vacuum port. A piston is positioned for reversible movement in the syringe cavity between the fluid port and the vacuum port so that movement of the piston in response to a decrease in fluid pressure causes a resilient element positioned within the cavity to be compressed. The compressed spring provides a store of mechanical energy that can be used to drive the piston toward the fluid port and expel fluid contained in the first cavity through the fluid port when pressure within the syringe cavity is equalized. Control of vacuum and air inlet into the syringe cavity is conveniently controlled by a dual port valve connected to the syringe body.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.