Infusion pump

• US 20060184123A1
• Filed: 12/28/2005
• Published: 08/17/2006
• Est. Priority Date: 06/14/2002
• Status: Active Grant

• Current Assignee: Baxter International Inc.
• Original Assignee: Baxter International Inc.
• Inventors: Spang, Ronald H. Jr., Berrill, James Frei, LaBedz, Ralph H., Platt, Michael Kenneth, Greaney, Michelle Kowalski, Gillespie, John Jr., Vogel, Matthew Stephen
• Granted Patent: US 7,608,060 B2
• Time in Patent Office: Days
• US Class Current: 604/155
• CPC Class Codes: A61M 2005/14208 with a programmable infusion control system, characterised by the infusion program
• CPC Class Codes: A61M 2005/14573 with a replaceable reservoir for quick connection/disconnection with a driving system
• CPC Class Codes: A61M 2205/21 insensitive to tilting or inclination, e.g. spill-over prevention
• CPC Class Codes: A61M 2205/6054 Magnetic identification systems
• CPC Class Codes: A61M 2205/8206 battery-operated
• CPC Class Codes: A61M 2205/8237 Charging means
• CPC Class Codes: A61M 2209/086 Docking stations
• CPC Class Codes: A61M 5/142 Pressure infusion, e.g. using pumps
• CPC Class Codes: A61M 5/14244 adapted to be carried by the patient, e.g. portable on the body
• 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 5/14566 with a replaceable reservoir for receiving a piston rod of the pump
• CPC Class Codes: A61M 5/172 electrical or electronic A61M5/16804, A61M5/16831 take precedence
• CPC Class Codes: G01B 7/00 Measuring arrangements characterised by the use of electric or magnetic techniques
• CPC Class Codes: G01B 7/003 for measuring position, not involving coordinate determination coordinate measuring G01B7/004
• CPC Class Codes: G06T 3/60 Rotation of whole images or parts thereof
• CPC Class Codes: G16H 20/17 delivered via infusion or injection

Abstract

A drive mechanism for an infusion pump linearly moves a syringe plunger within a syringe barrel supported by the pump and includes: (i) a motor; (ii) a lead screw rotatably connected to the motor; (iii) a slide assembly having a threaded member supported thereon, the threaded member being associated with the lead screw; (iv) an arm having one end connected to the slide assembly and one end adapted to be engaged with the syringe plunger, and (v) the threaded member being rotatably biased in engagement with the lead screw, wherein upon rotation of the lead screw by the motor, the slide assembly linearly moves the arm wherein the arm is adapted to move the syringe plunger within the syringe barrel.

Claims

1. A drive mechanism for an infusion pump, the drive mechanism adapted to linearly move a syringe plunger within a syringe barrel supported by the pump, the mechanism comprising:

a motor;

a lead screw rotatably connected to the motor;

a slide assembly having a threaded member supported thereon, the threaded member being associated with the lead screw;

an arm having one end connected to the slide assembly and one end adapted to be engaged with the syringe plunger,

the threaded member being rotatably biased in engagement with the lead screw, wherein upon rotation of the lead screw by the motor, the slide assembly linearly moves the arm wherein the arm is adapted to move the syringe plunger within the syringe barrel.

2. The drive mechanism of claim 1, further comprising a rail member, the rail member slidably supporting the slide assembly.

3. The drive mechanism of claim 2, wherein the rail member has a cover plate and a pair of legs depending from the cover plate.

4. The drive mechanism of claim 3, wherein the legs have an inwardly projecting portion.

5. The drive mechanism of claim 1, wherein the slide assembly has a base having a pair of cantilevered beams extending from the base, the cantilevered beams corresponding in shape to the legs of the rail member wherein the beams are slideable along the legs.

6. The drive mechanism of claim 1, wherein the slide assembly comprises a base and a cover, the base having a bore that receives the threaded member, the base further having a channel that receives the lead screw therethrough.

7. The drive mechanism of claim 1, wherein the threaded member is a rotary nut.

8. The drive mechanism of claim 7, wherein the rotary nut further comprises:

a base, the base having a post and ring extending therefrom, the ring being generally circumjacent to the post, the ring having a first notch defining a first engagement surface and a second notch defining a second engagement surface;

a first finger depending from the base, the first finger having a first threaded portion;

a second finger depending from the base, the second finger having a second threaded portion, the second finger being spaced from the first finger defining an opening therebetween, and wherein the lead screw is adapted to be received in the opening.

9. The drive mechanism of claim 7, wherein the arm supports a disengagement rod that is pivotable to linearly move and engage the first engagement surface and rotate the rotary nut to a disengaged position, wherein the threaded portions are not in engagement with the lead screw.

10. The drive mechanism of claim 7, wherein the cover supports a pin that engages the second engagement surface when the rotary nut is in the engaged position to prevent over-engagement with the lead screw.

11. A drive mechanism for an infusion pump, the drive mechanism adapted to linearly move a syringe plunger within a syringe barrel supported by the pump, the mechanism comprising:

a motor;

a lead screw rotatably connected to the motor;

a rail assembly;

a slide assembly slidably supported by the rail assembly, the slide assembly having a rotary nut supported thereon, the rotary nut having a threaded portion;

an arm having one end connected to the slide assembly and one end adapted to be engaged with the syringe plunger,

the rotary nut being rotatably biased wherein the threaded portion is engaged with the lead screw, wherein upon rotation of the lead screw by the motor the slide assembly linearly moves the arm, and wherein the arm is adapted to move the syringe plunger within the syringe barrel.

12. A rotary nut for a drive mechanism of a syringe infusion pump, the drive mechanism adapted to linearly move a syringe plunger within a syringe barrel supported by the pump, the drive mechanism having a lead screw rotatable by a motor, and further having a disengagement rod, the drive mechanism further having an arm having one end adapted to be connected to the rotary nut and another end adapted to engage the syringe plunger, the rotary nut comprising:

a cylindrical base, the base having a post and ring extending therefrom, the ring being generally circumjacent to the post, the ring having a first notch defining a first engagement surface and a second notch defining a second engagement surface;

a first finger depending from the base, the first finger having a first threaded portion;

a second finger depending from the base, the second finger having a second threaded portion, the second finger being spaced from the first finger defining an opening therebetween,

wherein the lead screw is adapted to be received in the opening, wherein the rotary nut has an engaged position wherein the first threaded portion engages a first side of the lead screw and the second threaded portion engages an opposite, second side of the lead screw, wherein the rotary nut linearly moves along the lead screw upon rotation of the lead screw by the motor, the second engagement surface engaging a pin when the rotary nut is in the engaged position to prevent over-engagement with the lead screw, the rotary nut being rotatable by the disengaging rod engaging the first engagement surface, and wherein the threaded portions are not in engagement with the lead screw.

13. A rotary nut for a drive mechanism of a syringe infusion pump, the drive mechanism having a rotatable lead screw, the rotary nut adapted for linear movement along the lead screw, the rotary nut comprising:

a body having an opening therethrough defining an inner surface, the inner surface having a threaded portion, the opening dimensioned such that when the body is rotated to a first position, the threaded portion engages the lead screw, wherein the rotary nut can move linearly along the lead screw in response to rotation of the lead screw and when the body is rotated to a second position, the threads disengage from the lead screw wherein the rotary nut can move freely along the lead screw.

14. A rotary nut for a drive mechanism of a syringe infusion pump, the drive mechanism having a rotatable lead screw, the rotary nut adapted for linear movement along the lead screw, the rotary nut comprising:

a body having an opening therethrough defining an inner surface, the inner surface having a threaded portion, the opening dimensioned such that when the body is rotated to an engaged position, the threaded portion engages the lead screw, wherein the nut linearly moves along the lead screw in response to rotation of the lead screw.