Safety syringe

• US 6,206,856 B1
• Filed: 03/13/2000
• Issued: 03/27/2001
• Est. Priority Date: 11/04/1998
• Status: Expired due to Term

• Current Assignee: Sudha S. Mahurkar Trust
• Original Assignee: Sakharam D. Mahurkar
• Inventors: Mahurkar, Sakharam D.
• Primary Examiner(s): Jasko, John
• Application Number:
  US09/523,842
• Time in Patent Office: 379 Days
• Field of Search: 604/195, 604/198, 604/192, 604/187, 604/263, 604/110
• US Class Current: 604/195
• CPC Class Codes: A61M 25/0606 "Over-the-needle" catheter assemblies, e.g. I.V. catheters
• CPC Class Codes: A61M 5/322 Retractable needles, i.e. disconnected from and withdrawn into the syringe barrel by the piston devices for protecting guide needles in combination with catheters A61M25/0612
• CPC Class Codes: A61M 5/3232 Semi-automatic needle retraction, i.e. in which triggering of the needle retraction requires a deliberate action by the user, e.g. manual release of spring-biased retraction means

Abstract

A single-use safety syringe assembly comprises an elongated, generally cylindrical barrel which forms a hollow nozzle located at the distal end of the barrel and which opens into the interior of the barrel. A plunger is slidably mounted in the barrel and forms a longitudinal cavity. A needle holder carries a hollow needle on its distal end, and the needle holder is slidably mounted in the longitudinal cavity of the plunger. A biasing arrangement urges the needle holder in a direction for retracting the needle into the barrel. However, a releasable latching arrangement retains the needle holder against the urging of the biasing arrangement in a position wherein the needle projects from the barrel. An In-Barrel assembly sequence is provided which permits sequentially inserting components of the syringe into the barrel and effecting assembly with a push of the plunger. An OTN catheter may also be employed in combination with the syringe assembly.

Claims

1. A safety syringe assembly, comprising:

an elongated, generally cylindrical barrel having a hollow interior forming a hollow nozzle located at a distal end of said barrel and opening into the interior of said barrel;

a plunger slidably mounted in said barrel and having a longitudinal channel;

a needle;

a needle holder mounting said needle at a distal end thereof and slidably mounted in said longitudinal channel of said plunger for movement between an advanced position in which said needle on the distal end of said needle holder projects from a distal end of said nozzle, and a retracted position in which said needle is retracted within said barrel;

a compression spring mounted inside said barrel and urging said needle holder toward its retracted position; and

a latch having a closed position in which said needle holder is latched relative to said barrel to hold said needle holder in its advanced position against the urging of said spring, and independently of the position of the plunger and an open position in which said needle holder is unlatched relative to said barrel to allow said spring to expand in a proximal direction to move said needle holder to its retracted position.

2. A syringe assembly comprising:

an elongated, generally cylindrical barrel forming a hollow nozzle located at the distal end of said barrel and opening into the interior of said barrel;

a plunger slidably mounted in the said barrel and forming a longitudinal channel;

a needle holder slidably mounted in said longitudinal open channel of the said plunger;

latching means for latching and unlatching said needle holder relative to the barrel and independently of the position of the plunger; and

elastic means located in said barrel for retracting said needle holder within the barrel in response to the unlatching of the needle holder from said barrel;

said latching means including a projecting element on one of said needle holder and said barrel by which the needle holder is directly or indirectly engaged with the barrel, at least when latching said needle holder relative to said barrel.