Safety syringe

• US 20070260192A1
• Filed: 05/05/2006
• Published: 11/08/2007
• Est. Priority Date: 05/05/2006
• Status: Abandoned Application

• Current Assignee: Linfair Engineering (HK) Co., Ltd.
• Original Assignee: Linfair Engineering (HK) Co., Ltd.
• Inventors: Lee, Chien-Yuan, Kao, Chih-Cheng
• Application Number:
  US11/418,969
• Publication Number:
  US 20070260192A1
• Time in Patent Office: Days
• US Class Current: 604/197
• CPC Class Codes: A61M 2005/3253 disconnecting the needle hub from the syringe barrel during removal of the sleeve from the syringe barrel
• CPC Class Codes: A61M 5/2466 by piercing without internal pressure increase A61M5/2429 takes precedence
• CPC Class Codes: A61M 5/3137 Specially designed finger grip means, e.g. for easy manipulation of the syringe rod
• CPC Class Codes: A61M 5/3243 being axially-extensible, e.g. protective sleeves coaxially slidable on the syringe barrel devices for protecting guide needles in combination with catheters A61M25/0612

Abstract

A safety syringe has a barrel, a retractor, a needle hub and an outer sleeve. The barrel has a plunger mounted slidably in the barrel, a front end and a threaded protrusion formed on the end and has a through hole. The retractor is hollow, engages the threaded protrusion and has a first connector. The needle hub has an enlarged end having a needle longitudinally extending through the needle hub and a second connector corresponding to and connecting detachably with the first connector. The outer sleeve is mounted slidably around the needle hub, is mounted detachably and slidably around the retractor and the barrel to mount in detachably and has a front end, a cavity, an inner surface, a positioning protrusion and an annular protrusion mounted in the inner surface. The syringe is assembled easily and conveniently.

Claims

1. A safety syringe comprising:

a barrel having

a rear open end;

a chamber defined in the barrel and communicating with the rear open end;

a front end;

a plunger mounted movably in the chamber in the barrel;

a threaded protrusion formed on the front end and having a through hole axially formed in the threaded protrusion;

a retractor being hollow and firmly engaged with the threaded protrusion and having

an outer surface; and

a first connector formed on the outer surface of the retractor;

a needle hub detachably connecting with the retractor and having

a body having

an outer diameter;

an inner surface;

a second connector formed in the inner surface of the body, corresponding to the first connector and detachably connecting with the first connector; and

a mounting hole formed through the body;

a needle mounted firmly in and longitudinally extending through the mounting hole of the body; and

an outer sleeve mounted slidably around the needle hub to mount slidably in, mounted detachably and slidably around the retractor and the barrel and having

a cavity defined in the outer sleeve and receiving the needle hub, the retractor and the barrel;

a rear open end;

a front end having a through hole defined through the front end and allowing the needle to extend through the through hole; and

an inner surface having

a positioning protrusion formed on the inner surface of the outer sleeve, adjacent to the through hole of the front end and positioning the needle hub; and

an annular protrusion formed on the inner surface of the outer sleeve, adjacent to the rear open end of the outer sleeve and having an inner diameter being smaller than the outer diameter of the body.

2. The safety syringe as claimed in claim 1, wherein the body of the needle hub further has an enlarged end corresponding to the retractor and having multiple recesses formed radially in the enlarged end at intervals.

3. The safety syringe as claimed in claim 1, wherein:

the first connector is an annular protrusion; and

the second connector is an annular groove corresponding to and connecting with the annular protrusion.

4. The safety syringe as claimed in claim 2, wherein:

the first connector is an annular protrusion; and

the second connector is an annular groove corresponding to and connecting with the annular protrusion.

5. The safety syringe as claimed in claim 1, wherein:

the first connector is an annular groove; and

the second connector is an annular protrusion corresponding to and connecting with the annular groove.

6. The safety syringe as claimed in claim 2, wherein:

the first connector is an annular groove; and

the second connector is an annular protrusion corresponding to and connecting with the annular groove.