Syringe pump drive system and disposable syringe cartridge

• US 4,067,332 A
• Filed: 08/25/1976
• Issued: 01/10/1978
• Est. Priority Date: 02/28/1975
• Status: Expired due to Term

• Current Assignee: IVAC Medical Systems, Inc. (Becton, Dickinson & Co)
• Original Assignee: Ivax Corporation (Teva Pharmaceutical Industries, Ltd.)
• Inventors: O'Leary, Stephen H.
• Primary Examiner(s): Truluck, Dalton L.
• Application Number:
  US05/717,769
• Time in Patent Office: 503 Days
• Field of Search: 128/214 R, 128/214 E, 128/214 F, 128/214.2, 128/230, 128/218 A, 128/234, 128/236, 128/273, 417/437
• US Class Current: 604/152
• CPC Class Codes: A61M 5/14216 Reciprocating piston type
• CPC Class Codes: A61M 5/1452 pressurised by means of pistons
• CPC Class Codes: Y10S 128/12 Pressure infusion

Abstract

A motor driven syringe pump utilizing a disposable syringe cartridge. The syringe cartridge has no valves, and the apparatus repetitively and sequentially opens and closes, by means of an external pair of tube pinchers, a pair of intake and output I.V. tubes communicating with the inlet and outlet nipples. The cartridge includes a molded plastic cylinder having inlet and outlet nipples, a plastic piston and piston rod, and a rubber sealing cap defining a conical piston face, a pair of piston sealing rings and a sealing boot. The pair of sealing rings enhance axial alignment and stability, while the sealing boot prevents air or bacterial intake through the bottom of the cylinder during repetitive strokes. The plastic cross-sections are selected to provide maximum strength for minimum material employed. The interior cylinder chamber is sloped to drive out gas through the outlet nipple. An integral tab on the cylinder provides an operator handle for mounting and removing the syringe. One end of the piston rod is cut away and provided with mounting bosses, adapted to engage and be retained by a cooperating drive system mounting shoe so that the syringe can be inserted in the shoe horizontally, be rotated to a vertical position, and engage fixed guide and retaining slots by means of a pair of integral bosses projecting from the syringe cylinder. The shoe is connected to a linear drive shaft keyed against rotation.

Claims

1. In a syringe pump, the combination comprising:

a syringe means having a piston and a piston rod;

a drive system for linearly reciprocating said piston and said piston rod, said piston rod having a pair of integral, outwardly extending mounting bosses adjacent a cut-away portion of said piston rod; and

a coupling shoe connected between said drive system and said piston rod, said coupling shoe having a pair of upstanding flanges containing a pair of oppositely disposed, confronting guide slots and a locking retention channel extending therebetween, said guide slots being adapted to receive said mounting bosses with the longitudinal axis of said syringe horizontal, enable rotation of said syringe to a position wherein said longitudinal axis is substantially vertical, and restrain said syringe against horizontal or vertical dislocation relative to said mounting shoe when said longitudinal axis is vertical.

2. In a syringe pump, the combination comprising:

a syringe cartridge having a cylinder, a piston and a piston rod;

a pair of outwardly extending mounting bosses on said cylinder;

a drive system for linearly reciprocating said piston and said piston rod within said cylinder;

a pair of integral, outwardly extending mounting bosses adjacent a cut-away portion of said piston rod;

a coupling shoe connected between said drive system and said piston rod, said coupling shoe having a pair of upstanding flanges containing a pair of oppositely disposed, confronting guide slots and a retention channel extending therebetween, said guide slots being adapted to receive said mounting bosses with the longitudinal axis of said syringe cartridge horizontal, enable rotation of said syringe cartridge to a position wherein said longitudinal axis is substantially vertical, and restrain said syringe cartridge against horizontal or vertical dislocation relative to said mounting shoe when said longitudinal axis is vertical; and

a syringe receiving compartment having a pair of oppositely disposed sidewalls, said sidewalls having defined therein a pair of confronting guide slots adapted to engage, guide and subsequently retain said mounting bosses projecting from said cylinder.

3. A combination as set forth in claim 2, wherein all of said guide slots are wide mouth slots.

4. A combination as set forth in claim 2, wherein the spacing between said guide slots in said coupling shoe and said guide slots in said sidewalls for start-up of the pump is such that the syringe cartridge can only be received in condition for initially performing a fill stroke.

5. A combination as set forth in claim 2, wherein said cylinder includes a tab for use as a handle in installing and removing said syringe cartridge from the syringe pump.

6. A combination as set forth in claim 2, wherein said syringe cartridge further includes a pair of I.V. tubes, one of said tubes being connected to said inlet nipple, the other of said tubes being connected to said outlet nipple.

7. A combination as set forth in claim 6, and further including means within said syringe pump for anchoring said I.V. tubes when said syringe cartridge has been installed.

8. A combination as set forth in claim 7, wherein said means for anchoring includes a pair of tube pinchers and an access door, between which said I.V. tubes are clamped.

9. In a syringe pump, the combination comprising:

a hollow syringe cylinder having an open end and a closed end, said cylinder being adapted for normal use with its longitudinal axis substantially vertical, said cylinder having a pair of inlet and outlet nipples projecting from said closed end of said cylinder, there being no valves within said nipples, the uppermost interior surface of said cylinder being sloped, said outlet nipple being located adjacent the highest point of said interior surface within said cylinder, said cylinder having

a pair of outwardly extending mounting bosses;

a syringe piston head within said cylinder;

a syringe piston rod connected to said piston head for reciprocating said piston head along said longitudinal axis of said cylinder, said piston rod having a pair of outwardly extending mounting bosses adjacent a partially cut-away portion of said piston rod;

a flexible sealing cap overlying and encasing said piston head, said cap defining an upwardly directed conical piston face, the slope of said conical face substantially conforming to the slope of said interior surface of said cylinder, said sealing cap further defining a pair of axially spaced apart sealing rings in engagement with the interior surface of said cylinder, said sealing cap having a limp membrane skirt adapted to seal said open end of said cylinder without stretching at any time during reciprocation of said piston head, said piston rod and said sealing cap, said skirt terminating in a thickened bead portion adapted to grip the external surface of said cylinder and prevent said sealing cap from being dislodged;

a syringe receiving compartment having a pair of oppositely disposed sidewalls, said sidewalls having defined therein a pair of confronting guide slots adapted to engage, guide and subsequently retain said mounting bosses projecting from said cylinder;

a drive system for linearly reciprocating said piston and said piston rod, said piston rod having a pair of outwardly extending mounting bosses adjacent a cut-away portion of said piston rod; and

a coupling shoe connected between said drive system and said piston rod, said coupling shoe having a pair of upstanding flanges containing a pair of oppositely disposed, confronting guide slots and a retention channel extending therebetween, said guide slots being adapted to receive said mounting bosses with the longitudinal axis of said syringe horizontal, enable rotation of said syringe to a position wherein said longitudinal axis is substantially vertical, and restrain said syringe against horizontal or vertical dislocation relative to said mounting shoe when said longitudinal axis is vertical.

10. A combination as set forth in claim 9, wherein the spacing between said guide slots in said coupling shoe and said guide slots in said sidewalls for start-up of the pump is such that the syringe can only be received in condition for initially performing a fill stroke.

11. A combination as set forth in claim 9, wherein said cylinder, said piston head, and said piston rod are molded plastic.

12. A combination as set forth in claim 9, wherein said sealing cap is rubber.

13. A combination as set forth in claim 9, wherein said piston rod has a substantially H cross-section perpendicular to the longitudinal axis of said piston rod.

14. A combination as set forth in claim 9, wherein said piston rod includes a pair of parallel longitudinally extending flanges joined by an integral crossbar.

15. A combination as set forth in claim 9, wherein said cylinder includes an integral tab for use as a handle in installing and removing said syringe cartridge from the syringe pump.

16. A combination as set forth in claim 9, wherein said syringe further includes a pair of I.V. tubes, one of said tubes being connected to said inlet nipple, the other of said tubes being connected to said outlet nipple.

17. A combination as set forth in claim 16, and further including means within said syringe pump for anchoring said I.V. tubes when said syringe cartridge has been installed.

18. A combination as set forth in claim 17, wherein said means for anchoring includes a pair of tube pinchers and an access door, between which said I.V. tubes are clamped.