Syringe assembly and infusion pump assembly incorporating such

• US 20080167618A1
• Filed: 01/10/2007
• Published: 07/10/2008
• Est. Priority Date: 01/10/2007
• Status: Active Grant

• Current Assignee: LifeScan IP Holdings, LLC
• Original Assignee: Animas Corporation (Johnson & Johnson)
• Inventors: Lawson, William, Sharifi, Bahram, Paul, Patrick
• Granted Patent: US 7,803,134 B2
• Time in Patent Office: Days
• US Class Current: 604/151
• CPC Class Codes: A61M 2005/31516 reducing dead-space in the syringe barrel after delivery
• CPC Class Codes: A61M 5/14244 adapted to be carried by the patient, e.g. portable on the body
• CPC Class Codes: A61M 5/14546 Front-loading type injectors
• CPC Class Codes: A61M 5/14566 with a replaceable reservoir for receiving a piston rod of the pump

Abstract

A syringe assembly for use with an infusion pump having a drive piston. The syringe assembly comprises a substantially hollow syringe housing and a plunger axially movable within the syringe housing to dispense a fluid therefrom. The plunger has a body with a portion thereof configured to engage a radially elastic member associated with the drive piston such that the plunger is releasably axially secured relative to the drive piston.

Claims

1. A syringe assembly for use with an infusion pump having a drive piston, the syringe assembly comprising:

a substantially hollow syringe housing;

a plunger axially movable within the syringe housing to expel a fluid therefrom, the plunger having a body with a portion configured to engage a radially elastic member associated with the drive piston such that the plunger is releasably axially secured relative to the drive piston.

2. The syringe assembly of claim 1 wherein the plunger body has a substantially hollow tubular configuration with an open end configured to receive a portion of the drive piston, the tubular body including an interior annular groove configured to receive a portion of the radially elastic member.

3. The syringe assembly of claim 2 wherein the interior annular groove has opposed side walls which are angled relative to one another by approximately 90 to 175 degrees.

4. The syringe assembly of claim 2 wherein the interior annular groove has opposed side walls which are angled relative to one another by approximately 135 degrees.

5. The syringe assembly of claim 2 wherein the plunger body open end is tapered inwardly.

6. The syringe assembly of claim 1 wherein at least a portion of the plunger body is configured to be received within a portion of the drive piston and the plunger body includes an exterior annular groove configured to receive a portion of the radially elastic member.

7. An infusion pump assembly comprising:

an insulin pump including a drive piston having a radially elastic member associated therewith; and

a syringe assembly including a substantially hollow syringe housing and a plunger axially movable within the syringe housing to expel a fluid therefrom, the plunger having a body with a portion configured to engage the radially elastic member associated with the drive piston such that the plunger is releasably axially secured relative to the drive piston.

8. The infusion pump assembly of claim 7 wherein the plunger body includes a first annular groove configured to receive a portion of the radially elastic member and the drive piston includes a second annular groove configured to receive a portion of the radially elastic member.

9. The infusion pump assembly of claim 8 wherein the first and second annular grooves are axially aligned when the plunger is positioned in a final assembled position relative to the drive piston.

10. The infusion pump assembly of claim 8 wherein the first annular groove has opposed side walls which are angled relative to one another by approximately 90 to 175 degrees.

11. The infusion pump assembly of claim 8 wherein the interior annular groove has opposed side walls which are angled relative to one another by approximately 135 degrees.

12. The infusion pump assembly of claim 8 wherein the second annular groove is radially deeper than the first annular groove.

13. The infusion pump assembly of claim 8 wherein the plunger body has a substantially hollow tubular configuration with an open end configured to receive a portion of the drive piston and the first annular groove is an interior groove and the second annular groove is an external groove.

14. The infusion pump assembly of claim 8 wherein at least a portion of the plunger body is configured to be received within a portion of the drive piston and the first annular groove is an exterior groove and the second annular groove is an internal groove.

15. The infusion pump assembly of claim 7 wherein the radially elastic member is a canted coil spring.

16. The infusion pump assembly of claim 7 wherein the radially elastic member is a solid ring manufactured from an elastomeric material.

17. An infusion pump assembly comprising:

an insulin pump including a drive piston with a first annular groove;

a syringe assembly including a substantially hollow syringe housing and a plunger axially movable within the syringe housing to expel a fluid therefrom, the plunger having a body engagable with the drive piston and including a second annular groove; and

a radially elastic member positional within the first and second grooves to releasably, axially secure the plunger relative to the drive piston.

18. The infusion pump assembly of claim 17 wherein the plunger is engaged with and releasably axially secured to the drive piston via an axial force in a first direction.

19. The infusion pump assembly of claim 18 wherein a sufficient axial force in a second direction opposite the first direction releases the plunger with respect to the drive piston.

20. The infusion pump assembly of claim 19 wherein a friction force exists between the syringe housing and the plunger which is greater than the force required to engage the plunger to the drive piston and greater than the force required to release the plunger with respect to the drive piston.