Automatic self-protecting hypodermic needle assembly
US5224936A · kind A · utility
Inventor
Key dates
| Filing date | Oct 15, 1992 |
| Grant date | Jul 6, 1993 |
| Priority date | — |
| Expiry date | Oct 15, 2012 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61M2005/325
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An automatic self-protecting hypodermic needle assembly comprising a hypodermic syringe having a housing, a moveable plunger in the housing, a medicant chamber formed between the housing and the plunger, and a hollow needle extending from the housing in communication with the medicant chamber. A needle guard assembly is attached to the syringe housing and includes a guard housing adjacent the needle, a protective cap removably attached to the guard housing and an aperture through which the needle extends. A propellant is located in the guard housing in communication with the protective cap. When activated by an activating element, the propellant expands from a liquid to a gas, applies a pressure to the protective cap, and drives the protective cap along the length of the needle until the cap extends beyond the tip of the needle and the needle tip becomes embedded in the protective cap. Control means are provided under the operation of the medical attendant using the hypodermic syringe to automatically activate the propellant upon completion of the use of the syringe, and to embed the needle tip into the protective cap.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.