Syringe/Plunger Coupling

• US 20080033358A1
• Filed: 10/15/2007
• Published: 02/07/2008
• Est. Priority Date: 02/05/1999
• Status: Active Grant

• Current Assignee: Liebel-Flarsheim Company (Mallinckrodt plc)
• Original Assignee: Liebel-Flarsheim Company (Mallinckrodt plc)
• Inventors: Bergen, Robert, Goethel, James
• Granted Patent: US 8,353,879 B2
• Time in Patent Office: Days
• US Class Current: 604/132
• CPC Class Codes: A61M 5/007 for contrast media
• 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
• CPC Class Codes: A61M 5/31515 Connection of piston with piston rod
• CPC Class Codes: Y10S 128/01 Motorized syringe

Abstract

A medical fluid injector, replaceable syringe, and coupling mechanism to engage the syringe plunger to the plunger drive ram of the injector are provided wherein coupling involves a cam cleat-like mechanism, thereby allowing for cooperative movement between the plunger drive ram and syringe plunger. The coupling mechanism of the plunger drive ram is provided with first and second movable members, each having toothed, arcuate surfaces, while the coupling mechanism of the syringe plunger is provided with a knurled cavity. Disengagement of the coupling mechanism is facilitated by translational movement of a face plate located on the forward end of the injector housing.

Claims

1. (canceled)

3. The assembly of claim 1, wherein the drive ram comprises a movable member that is movable in a direction non-parallel to the longitudinal axis of the drive ram, and wherein the movable member is located within the interior cavity defined in the plunger.

4. The assembly of claim 1, wherein the drive ram comprises first and second movable members, each of which is movable in a direction non-parallel to the longitudinal axis of the drive ram, and wherein the first and second movable members are located within the interior cavity defined in the plunger.

5. The assembly of claim 1, wherein the drive ram comprises a movable member that is movable in a direction substantially perpendicular to the longitudinal axis of the drive ram, and wherein the movable member is located within the interior cavity defined in the plunger.

6. The assembly of claim 1, wherein the drive ram comprises first and second movable members, each of which is movable in a direction substantially perpendicular to the longitudinal axis of the drive ram, and wherein the first and second movable members are located within the interior cavity defined in the plunger.

7. The assembly of claim 1, wherein the drive ram comprises a movable member that is movable toward and away from the longitudinal axis of the drive ram, and wherein the movable member is located within the interior cavity defined in the plunger.

8. The assembly of claim 1, wherein the drive ram comprises first and second movable members, each of which is movable toward and away from the longitudinal axis of the drive ram, wherein the first and second movable members are located within the interior cavity defined in the plunger.

9. The assembly of claim 6, wherein the interior cavity comprises at least one feature that interfaces with the movable member to assist in cooperative motion of the drive ram and the plunger relative to the barrel of the syringe.

10. The assembly of claim 6, wherein the movable member is pivotable toward and away from the longitudinal axis of the drive ram.

11. The assembly of claim 9, wherein the movable member comprises first and second pawls.

12. The assembly of claim 10, wherein a wall that defines at least a portion of the interior cavity in the plunger is knurled.

13. The assembly of claim 10, wherein the interior cavity in the plunger exhibits a T-shaped cross-section.

14. The assembly of claim 1, wherein the plunger comprises a rearwardly extending cylindrical extension, and at least a portion of the interior cavity in the plunger is defined in the rearwardly extending cylindrical extension.

15. The assembly of claim 1, further comprising an injector housing having an opening defined therein through which the drive ram moves.

16. The assembly of claim 14, wherein the injector housing comprises a removable face plate to which the syringe is mounted, wherein the opening is defined in the removable face plate.

17. The assembly of claim 15, wherein the removable face plate comprises a pressure jacket, wherein the barrel of the syringe is located within the pressure jacket.

18. The assembly of claim 1, further comprising a pressure jacket designed to accommodate at least a portion of the syringe, wherein the barrel of the syringe is located within the pressure jacket.

19. The assembly of claim 1, wherein the syringe has medical fluid for use in a diagnostic imaging procedure disposed therein.

21. The syringe of claim 19, wherein the interior cavity defined in the plunger comprises at least one feature that interfaces with the component to assist in cooperative motion of the drive ram and the plunger relative to the barrel of the syringe.

22. The syringe of claim 19, wherein a wall that defines at least a portion of the interior cavity in the plunger is knurled.

23. The syringe of claim 19, wherein the interior cavity in the plunger exhibits a T-shaped cross-section.

24. The syringe of claim 19, wherein the plunger comprises a rearwardly extending cylindrical extension, and at least a portion of the interior cavity in the plunger is defined in the rearwardly extending cylindrical extension.

25. The syringe of claim 19, further comprising medical fluid for use in a diagnostic imaging procedure disposed therein.

2. A contrast media injector assembly comprising:

a syringe comprising;

a barrel having a forward end and an opposing rear end;

a front wall section integral with the forward end of the barrel;

a neck that extends forwardly from and is integral with the front wall section, wherein the neck terminates in a discharge tip; and

a plunger disposed within and snugly slidable within and relative to the barrel, wherein the plunger comprises a forward facing surface having a surface which substantially conforms to a surface of an interior of the front wall section of the syringe, and wherein the plunger further comprises a rearward face having an interior cavity defined therein;

a drive ram that is movable relative to the barrel of the syringe to couple with and move the plunger of the syringe relative to the barrel, wherein the drive ram comprises a longitudinal axis along which the drive ram is movable, and wherein at least a portion of the drive ram is located within the interior cavity defined in the rearward face of the plunger of the syringe; and

a motor to deploy the drive ram and the plunger in motion along the longitudinal axis of the drive ram relative to the barrel of the syringe.

20. A syringe for use with a contrast media injector, the syringe comprising:

a barrel having a forward end and an opposing rear end;

a front wall section integral with the forward end of the barrel;

a neck that extends forwardly from and is integral with the front wall section, wherein the neck terminates in a discharge tip; and

a plunger disposed within and snugly slidable within and relative to the barrel, wherein the plunger comprises;

a forward facing surface having a surface which substantially conforms to a surface of an interior of the front wall section of the syringe;

a rearward face having an interior cavity defined therein that is designed to accommodate a drive ram of a contrast media injector, wherein the interior cavity of the plunger is designed to allow lateral movement of a component of the drive ram relative to a longitudinal axis of a drive shaft of the drive ram when the component is located within the interior cavity defined in the plunger.

26. A method of operation for a contrast media injection system, the method comprising:

engaging a plunger of a syringe with a drive ram of a motorized contrast media injector, wherein the engaging comprises inserting the drive ram into an interior cavity defined in the plunger while the plunger is located within the syringe; and

moving at least a portion of the drive ram that is located within the interior cavity defined in the plunger, wherein the moving occurs in a direction substantially different than a direction of movement of the plunger when moved within the syringe by the drive ram of the motorized contrast media injector.