Non-reusable retractable safety syringe

• US 5,944,692 A
• Filed: 01/12/1998
• Issued: 08/31/1999
• Est. Priority Date: 09/13/1996
• Status: Expired due to Term

• Current Assignee: Saf-T-Med, Inc. (Becton, Dickinson & Co)
• Original Assignee: Saf-T-Med, Inc. (Becton, Dickinson & Co)
• Inventors: McGary, R. Kern, Jentzen, S. William
• Primary Examiner(s): YASKO JR, JOHN D
• Application Number:
  US09/005,902
• Time in Patent Office: 596 Days
• Field of Search: 604/110, 604/195, 604/218, 604/228, 604/263, 604/198, 604/187
• US Class Current: 604/110
• CPC Class Codes: A61M 2005/5073 by breaking or rupturing the connection parts
• CPC Class Codes: A61M 5/3202 Devices for protection of the needle before use, e.g. caps A61M5/50 takes precedence; for infusion spikes A61M5/1626; protectors for sharps A61B50/3001
• CPC Class Codes: A61M 5/3234 Fully automatic needle retraction, i.e. in which triggering of the needle does not require a deliberate action by the user
• CPC Class Codes: A61M 5/5066 Means for preventing re-use by disconnection of piston and piston-rod
• CPC Class Codes: A61M 5/508 Means for preventing re-use by disrupting the piston seal, e.g. by puncturing

Abstract

A non-reusable retractable safety syringe is provided which has a hollow plunger and a seal member carried thereon. The provision of the plunger and the seal relative to the barrel permits the plunger, with sufficient strength, to carry applied pressure through the device during injection of a medicinal or other fluid into a patient, and yet permit the seal disposed at one end of the plunger to have maximum sealing integrity between the plunger and a cylindrical barrel disposed around the exterior of the plunger, to abate leakage of the liquid in a chamber within the barrel, as the plunger is manipulated from an expanded position to an expended position and thereafter to a third, or collapsed position. Designs for securing the seal relative to the plunger are disclosed. The syringe may be used to insert and/or withdraw fluid relative to the patient.

Claims

1. A non-reusable retractable safety syringe comprising:

(a) a cylindrical barrel having first and second barrel ends and an inside diameter wall there between;

(b) a chamber for receipt of fluid within said barrel and between said first and second barrel ends;

(c) a plastic hollow plunger extendable into said barrel through the first end of said barrel, and selectively movable from expanded position toward an expended position;

(d) means for permitting the plunger to thereafter move to a collapsed position relative to the second end of the barrel;

(e) a hollow needle in secured relationship relative to the second end of the barrel;

(f) biasing means in initially secured relationship relative to the second end of the barrel for biasing the needle toward the hollow plunger;

(g) means for directing forward pressure upon said plunger;

(h) sealing means including an elastomeric sealing member and engaged to one end of the plunger for slidable sealing engagement with the inside diameter wall of the barrel;

(i) a cutting tip carried by the plunger for cutting through the sealing member such that the biasing means thereafter releases the needle into the plunger when the plunger is at the collapsed position relative to the second end of the barrel; and

(j) means for engaging the plunger to the sealing means, said engaging means being provided through heat staking to form at least one heat stake weld.

2. A non-reusable retractable safety syringe comprising:

(a) a cylindrical barrel having first and second barrel ends and an inside diameter wall there between;

(b) a chamber for receipt of fluid within said barrel and between said first and second barrel ends;

(c) a plastic hollow plunger extendable into said barrel through the first end of said barrel, and selectively movable from expanded position toward an expended position;

(d) means for permitting the plunger to thereafter move to a collapsed position relative to the second end of the barrel;

(e) a hollow needle in secured relationship relative to the second end of the barrel;

(f) biasing means in initially secured relationship relative to the second end of the barrel for biasing the needle toward the hollow plunger;

(g) means for directing forward pressure upon said plunger;

(h) sealing means including an elastomeric sealing member and engaged to one end of the plunger for slidable sealing engagement with the inside diameter wall of the barrel;

(i) a cutting tip carried by the plunger for cutting through the sealing member such that the biasing means thereafter releases the needle into the plunger when the plunger is at the collapsed position relative to the second end of the barrel; and

(j) means for engaging the plunger to the sealing means, said engaging means being provided through ultrasonic energy to form at least one ultrasonic weld.