Dual chamber internal by-pass syringe assembly

• US 5,685,846 A
• Filed: 02/27/1995
• Issued: 11/11/1997
• Est. Priority Date: 02/27/1995
• Status: Expired due to Fees

• Current Assignee: Schott Parenta Systems, Inc.
• Original Assignee: Schott Parenta Systems, Inc.
• Inventors: Michaels, Thomas M. Jr.
• Primary Examiner(s): Buiz, Michael Powell
• Assistant Examiner(s): Gring, N. Kent
• Application Number:
  US08/394,712
• Time in Patent Office: 988 Days
• Field of Search: 604/89, 604/82, 604/85, 604/84, 604/90, 604/91, 604/181, 604/191, 604/218, 604/187, 604/219, 604/221, 604/222, 604/225, 604/230, 604/231
• US Class Current: 604/90
• CPC Class Codes: A61M 5/31596 comprising means for injection of two or more media, e.g. by mixing

Abstract

A syringe device for use with two components to be combined prior to discharge, comprising a syringe body without the proximal end, a syringe plunger rod threadedly engageable into a plunger and a lined seal for engagement with a needle hub. The syringe body has at the distal end a radially inwardly directed internal sealing ring dividing the body to define a distal chamber and a proximal chamber. Also provided is an internal bypass stopper sized to fit the syringe body and engage the sealing ring to sealingly separate the distal chamber and the proximal chamber. The stopper has a plurality of projections circumferentially spaced thereon for engagement with the syringe body on at least one side of the sealing ring. The projections define by-pass channels therebetween to permit flow of liquid from the proximal chamber to the distal chamber upon movement of the stopper toward the distal end.

Claims

1. A syringe assembly comprising:

an elongated hollow tubular barrel having an inner peripheral surface and a discharge opening at one end and;

means defining a radially inwardly directed circumferentially extending rib in the inner peripheral surface of said barrel dividing said barrel into a first medicament chamber on one side of said rib and a second diluent chamber on the opposite side of said rib;

a by-pass stopper engageable interiorly of said barrel having a circumferentially extending exterior sealing surface of a predetermined diameter greater than the diameter of the rib to provide a seal between said chambers when engaged therewith and means defining at least one axially extending flow path on at least one side of said sealing surface providing fluid communication between said chambers when said stopper is displaced axially relative to the rib.

2. The syringe assembly of claim 1 wherein said bypass stopper includes projections circumferentially spaced on both sides of a central portion, said central portion circumferentially engaging said sealing rib.

3. The syringe assembly of claim 1 wherein said bypass stopper includes a plurality of projections circumferentially spaced thereon only on the diluent chamber side of the by-pass stopper.

4. The syringe assembly of claim 3 wherein said internal by-pass stopper includes a cone shaped end facing said first medicament.

5. The syringe assembly of claim 1 which further includes a needle hub assembly for mounting a needle on said device.

6. A method for dispensing two components to be combined prior to discharge using a syringe having a distal end and a proximal end, comprising the steps of:

placing a liquid in the proximal end of a syringe and a medicament mixable with said liquid in the distal end of said syringe, said syringe including a body having a radially inwardly directed internal sealing rib to define said distal and proximal chambers and a by-pass stopper having a portion sealingly separating said chambers, and a plurality of projections circumferentially spaced thereon on at least one side of said sealing portion defining by-pass channels;

moving said by-pass stopper axially to displace the sealing portion from the rib to permit flow of liquid through said by-pass channels from said proximal end to said distal end to form a dispensable combination of said liquid and said medicament; and

dispensing said dispensable combination as desired.

7. The method of claim 6 wherein said by-pass stopper includes projections circumferentially spaced on both sides of a central portion, said central portion circumferentially engaging said sealing ring to provide a sealing engagement therebetween.

8. The method of claim 6 wherein said by-pass stopper includes a plurality of projections circumferentially spaced thereon only on the side of the by-pass stopper facing said distal end of the syringe.

9. The method of claim 6 wherein said internal by-pass stopper includes a cone shaped end facing said distal chamber.

10. The method of claim 6 which further includes a needle hub assembly for mounting a needle on said device.