Dental safety syringe

Patent metadata

Field	Value
Publication number	US-11141531-B2
Application number	US-201815917208-A
Country	US
Kind code	B2
Filing date	Mar 9, 2018
Priority date	Mar 9, 2017
Publication date	Oct 12, 2021
Grant date	Oct 12, 2021

Abstract

A dental safety syringe comprising selectively attachable barrel and plunger assemblies, the barrel assembly desirably further comprising a needle cartridge containing a needle holder and spring, and having a distal end from which a needle can be made to project forwardly while administering a medication and then subsequently withdrawn into the needle cartridge to avoid contamination following or between injections. The needle cartridge also comprises a proximal end having a recess into which an ampule containing medication can be inserted prior to connecting the plunger assembly to the barrel assembly so that a rubber dam in the distal end of the ampule is pierced by the proximal end of the needle whenever the syringe is fully assembled.

First claim

What is claimed is:

1. A dental safety syringe comprising a barrel assembly and a cooperatively configured plunger assembly slidably engageable with the barrel assembly:
the barrel assembly further comprising a reusable barrel with a longitudinally extending window and projecting lugs, and a removable needle cartridge insertable into the reusable barrel through the window; and
the cooperatively configured plunger assembly further comprising a plunger body with open proximal and distal ends, an outside surface and slots disposed on the outside surface, a plunger rod slidably insertable into the plunger body having a proximal end and a distal end, and having a thumb ring attached to the proximal end of the plunger rod and a harpoon attached to the distal end of the plunger rod;
wherein the removable needle cartridge is disposed forwardly of an ampule containing a medication and further comprises a needle, a needle holder biased rearwardly by a compressible spring disposed inside the removable needle cartridge and a distal end from which the needle can be made to project forwardly while administering the medication from the ampule and then subsequently withdrawn into the removable needle cartridge to avoid contamination following or between injections; and
wherein the projecting lugs of the reusable barrel of the barrel assembly are cooperatively engageable and alignable with the slots disposed on the outside surface of the plunger body and configured to allow both axial and rotational movement of the plunger body relative to the reusable barrel to move the needle to initiate withdrawal of the needle into the removable needle cartridge and reusable barrel whenever the plunger body is moved rearwardly relative to the reusable barrel.

2. The dental safety syringe of claim 1 wherein the needle holder further comprises a recess in which a distal end of the ampule containing the medication can be placed during attachment of the cooperatively configured plunger assembly to the barrel assembly to establish fluid communication between the ampule and the needle.

3. The dental safety syringe of claim 1 wherein the removable needle cartridge is disposable following use.

4. The dental safety syringe of claim 1 wherein the barrel assembly and the cooperatively configured plunger assembly are cooperatively configured to make the needle project forwardly from a distal end of the reusable barrel when the plunger body is moved forwardly in relation to the reusable barrel.

5. The dental safety syringe of claim 1 wherein the barrel assembly and the cooperatively configured plunger assembly are cooperatively configured so that the entire needle is withdrawn into the removable needle cartridge when the plunger body is moved rearwardly in relation to the reusable barrel.

6. The dental safety syringe of claim 1 wherein a fluid flow path is established through the dental safety syringe that causes medication to flow through the needle and into a patient whenever the plunger rod is pushed forwardly relative to the plunger body and the reusable barrel.

Assignees

• Retractable Technologies Inc
• Shaw Thomas J

Inventors

• Shaw Thomas J
• Small Mark

Classifications

• A61M5/24 Primary

  Ampoule syringes, i.e. syringes with needle for use in combination with replaceable ampoules or carpules, e.g. automatic {(ampoules or carpules A61J1/06)} · CPC title

• A61M5/3221

  Constructional features thereof, e.g. to improve manipulation or functioning · CPC title

• A61M5/3271

  with guiding tracks for controlled sliding of needle protective sleeve from needle exposing to needle covering position · CPC title

• A61M2005/3247

  Means to impede repositioning of protection sleeve from needle covering to needle uncovering position · CPC title

• A61M2005/2407

  from the rear · CPC title