Retractable needle syringe with integral spring
US4820275A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 1987 |
| Grant date | Apr 11, 1989 |
| Priority date | — |
| Expiry date | Dec 21, 2007 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61M2005/3247
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A dental syringe of the type having a pre-filled cartridge of fluid medication and a double ended hypodermic needle communicating with the cartridge for injecting the contents thereof into a targeted tissue area of a patient. The cartridge is carried within an inner syringe cylinder, and the inner cylinder is slideable through an outer syringe cylinder. The inner cylinder has a pair of axially spaced locking grooves which extend around the periphery thereof. The outer cylinder includes a finger ring having an integral, inwardly projecting tab. The finger ring is hingedly connected to the outer cylinder so that the integral tab may be rotated into or out of engagement with either one of the pair of locking grooves of the inner cylinder. With the tab engaging a first of the locking grooves, the inner cylinder is retained at a relatively proximal position within the outer cylinder so that the needle is located inwardly of and completely shielded thereby to prevent an accidental needle strike. With the tab engaging a second of the locking grooves, the inner cylinder is retained at a relatively distal position within the outer cylinder so that the needle is extended outwardly thereof fo…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.