Loading mechanism for infusion pump

• US 7,306,578 B2
• Filed: 01/04/2002
• Issued: 12/11/2007
• Est. Priority Date: 01/04/2002
• Status: Expired due to Fees

• Current Assignee: Eugly Diabetes Care LLC
• Original Assignee: Deka Products Limited Partnership
• Inventors: Gray, Larry B., Lanigan, Richard
• Primary Examiner(s): Lucchesi, Nicholas D.
• Assistant Examiner(s): DeSanto, Matthew F.
• Application Number:
  US10/037,614
• Publication Number:
  US 20030130618A1
• Time in Patent Office: 2,167 Days
• Field of Search: 604/131, 604/133, 604151-155, 604/208, 604/209, 604/211, 604/228, 604/DIG.1, 604/224, 604/110, 604/187, 604/207, 604/232, 128/DIG.13, 128/DIG.12
• US Class Current: 604/151
• CPC Class Codes: A61M 2005/14573 with a replaceable reservoir for quick connection/disconnection with a driving system
• CPC Class Codes: A61M 2005/1581 Right-angle needle-type devices
• CPC Class Codes: A61M 2005/1587 suitable for being connected to an infusion line after insertion into a patient
• CPC Class Codes: A61M 25/0612 Devices for protecting the needle; Devices to help insertion of the needle, e.g. wings or holders
• CPC Class Codes: A61M 39/1011 Locking means for securing connection; Additional tamper safeties A61M39/16 takes precedence
• CPC Class Codes: A61M 39/14 for connecting tubes having sealed ends needle sets A61M5/162; having valves closing automatically on disconnection of line A61M39/26
• CPC Class Codes: A61M 5/14 Infusion devices, e.g. infusing by gravity; Blood infusion; Accessories therefor
• CPC Class Codes: A61M 5/142 Pressure infusion, e.g. using pumps
• CPC Class Codes: A61M 5/1452 pressurised by means of pistons
• CPC Class Codes: A61M 5/14546 Front-loading type injectors
• CPC Class Codes: A61M 5/1456 with a replaceable reservoir comprising a piston rod to be moved into the reservoir, e.g. the piston rod is part of the removable reservoir
• CPC Class Codes: A61M 5/158 Needles for infusions; Accessories therefor, e.g. for inserting infusion needles, or for holding them on the body

Abstract

A loading mechanism for a medication infusion pump. The mechanism includes a medication reservoir, a plunger, a threaded plunger rod offset from the axis of the reservoir and an infusion pump with a drive screw that is offset from the axis of a pump barrel. The pump barrel receives the assembly comprising the reservoir, plunger and plunger rod.

Claims

1. A drive assembly for an infusion pump, the assembly comprising:

a. a reservoir for containing a fluid, the reservoir being the exclusive component of the drive assembly capable of containing a fluid for infusion;

b. a barrel, distinct from the reservoir, for holding the reservoir, the barrel characterized by a longitudinal barrel axis of rotation and a clearance hole in a barrel end;

c. a rotating drive screw, the drive screw having a longitudinal screw axis and exterior threads, the screw axis displaced from and parallel to the barrel axis; and

d. a plunger rod, the rod having threads at least part of its length, the rod inserted through the clearance hole, the rod threads interlocking with and disengaging from the screw threads by rotating the barrel about the barrel axis.

2. A drive assembly according to claim 1, wherein the reservoir includes a plunger in engagement with the plunger rod, the plunger when axially displaced causing a change in volume in the reservoir;

the drive assembly further including a locking hub, the hub in mechanical connection with the reservoir and the barrel, the hub capable of rotating the barrel, forcing the rod threads into and out of mechanical engagement with the drive screw threads.

3. A drive assembly according to claim 2 wherein the barrel further includes a locking tab to inhibit rotation of the barrel about the barrel axis and the locking hub includes a flange, the flange for dislodging the locking tab allowing the barrel to rotate.

4. A drive assembly according to claim 2 wherein the locking hub further includes an adapter, the adapter for receiving the reservoir, the adapter providing an axial offset to the reservoir so that the plunger rod threads can engage with the drive screw threads.

5. A drive assembly according to claim 1 wherein the drive screw threads and the rod threads are buttress threads.

6. A drive assembly according to claim 1 wherein the barrel further includes a locking tab to inhibit rotation of the barrel about the barrel axis.

7. A drive assembly for an infusion pump, the assembly comprising:

a fluid reservoir containing a fluid for delivery by the pump;

a pump barrel having a longitudinal barrel axis and holding the fluid reservoir;

a plunger rod having a single longitudinal rod axis parallel to and displaced from the longitudinal barrel axis and threaded along at least a portion of its length, the plunger rod terminating in a plunger at one end of the single longitudinal rod axis, the plunger being inserted into one end of the fluid reservoir so as to change the volume of the reservoir as the plunger is displaced within the reservoir; and

a threaded drive screw having a longitudinal screw axis parallel to and displaced from the single longitudinal rod axis;

the assembly being characterized by;

(i) a loading position in which the plunger rod threads and the drive screw threads are not engaged so as to facilitate loading fluid into the fluid reservoir, and

(ii) an operating position in which the plunger rod threads and the drive screw threads are engaged such that rotation of the drive screw displaces the plunger to change the volume of the reservoir to deliver fluid out from the reservoir.

8. A drive assembly according to claim 7, wherein rotation between the plunger rod and the drive screw engages and disengages them to switch from one operating position to another.

9. A drive assembly according to claim 7, further comprising:

a locking hub for controlling the engaging and disengaging of the plunger rod threads and the drive screw threads.

10. A drive assembly according to claim 7, wherein the plunger rod threads and the drive screw threads are buttress threads.