Syringe pump drive system and disposable syringe cartridge

• US 3,993,061 A
• Filed: 02/28/1975
• Issued: 11/23/1976
• Est. Priority Date: 02/28/1975
• Status: Expired due to Term

• Current Assignee: New Ivac, Inc.
• Original Assignee: Ivax Corporation (Teva Pharmaceutical Industries, Ltd.)
• Inventors: O'Leary, Stephen H.
• Primary Examiner(s): Truluck, Dalton L.
• Application Number:
  US05/554,230
• Time in Patent Office: 634 Days
• Field of Search: 128/214, 128/215, 128/218, 128/219, 128/234-238, 128/273, 128/278, 128/DIG. 1, 128/DIG. 12, 417/437, 92/98 D, 92/105, 92/170
• 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 parenteral administration system, utilizing a syringe pump operated by a motor to repetitively fill and empty a disposable syringe cartridge over a plurality of operational cycles of successive fill and pump stroke periods. 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 disposable syringe 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.

Claims

1. For use in a syringe pump having a housing and a syringe mounting, a syringe, comprising:

a hollow 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 integral, parallel inlet and outlet nipples projecting from said closed end of said cylinder, said nipples being disposed on opposite sides of said cylinder with the axes of said nipples being substantially parallel to said longitudinal axis of said cylinder, there being no valves within said nipples, the uppermost interior surface of said cylinder being sloped upwardly in a single plane, said outlet nipple being located adjacent the highest point within said cylinder;

a piston head with said cylinder; and

a piston rod connected to said piston head and integral therewith for reciprocating said piston head along said longitudinal axis of said cylinder.

2. Apparatus as set forth in claim 1, wherein said piston rod has a pair of integral, outwardly extending mounting bosses adapted to engage the mounting means of a piston drive system.

3. Apparatus as set forth in claim 1, wherein said cylinder has a pair of integral, outwardly extending mounting bosses adapted to engage mounting means in a syringe receiving compartment.

4. Apparatus as set forth in claim 1, and further including a flexible sealing cap overlying and encasing said piston head, said cap defining a piston face, 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.

5. For use in a syringe pump having a housing and a syringe mounting, a syringe, comprising:

a hollow 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, said nipples being disposed on opposite sides of said cylinder with the axes of said nipples being substantially parallel to said longitudinal axis of said cylinder, the uppermost interior surface of said cylinder being sloped upwardly in a single plane, said outlet nipple being located adjacent the highest point within said cylinder;

a piston head within said cylinder;

a piston rod connected to said piston head for reciprocating said piston head along said longitudinal axis of said cylinder; and

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 conforming to the slope of said interior surface of said cylinder.

6. For use in a syringe pump, a syringe, comprising:

a hollow cylinder;

a piston head within said cylinder;

a piston rod connected to said piston head for reciprocating said piston head along the longitudinal axis of said cylinder;

said piston rod having a pair of integral, outwardly extending mounting bosses at the opposite end of said piston rod from said piston head, said piston rod further having at the same end as said bosses a cut-away portion adjacent the bosses and extending along one side thereof, said mounting bosses and said cut-away portion constituting means for engaging the mounting means of a piston drive system in only a single position, said syringe being rotatable about an axis of rotation through said mounting bosses to lock said syringe in its operative position with its longitudinal axis positioned vertically and retained by said mounting means for operation of said syringe through repetitive fill and pump cycles.

7. Apparatus as set forth in claim 6, wherein said cylinder, said piston head, and said piston rod are molded plastic.

8. Apparatus as set forth in claim 6, wherein said piston rod has a substantially H cross-section perpendicular to the longitudinal axis of said piston rod.

9. Apparatus as set forth in claim 6, wherein said piston rod includes a pair of parallel longitudinally extending flanges joined by an integral crossbar.

10. Apparatus as set forth in claim 8 and further including a flexible sealing cap overlying and encasing said piston head, said cap defining a piston face, 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.

11. For use in a syringe pump having a housing and a syringe mounting, the combination comprising:

a syringe having a piston and 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 defining a yoke with a passageway for receipt of said mounting bosses, said yoke and said mouting bosses together defining locking means enabling rotation of said syringe in only one direction to an operable position and restraining said syringe against dislocation relative to said coupling shoe while said syringe is in said operable position.

12. For use in a syringe pump, a disposable syringe cartridge, comprising:

a hollow 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 integral, parallel inlet and outlet nipples projecting from said closed end of said cylinder, said nipples being disposed on opposite sides of said cylinder with the axes of said nipples being substantially parallel to said longitudinal axis of said cylinder, there being no valves within said nipples, the uppermost interior surface of said cylinder being sloped upwardly in a single plane, said outlet nipple being located adjacent the highest point within said cylinder;

a piston head within said cylinder, said piston head having spaced apart parallel annular flanges;

a piston rod connected to said piston head and integral therewith for reciprocating said piston head along said longitudinal axis of said cylinder, said piston rod having a pair of integral, outwardly extending mounting bosses adjacent a partially cut-away portion of said piston rod, said mounting bosses and said cut-away portion being adapted to engage the mounting means of a piston drive system, whereby said syringe can be mounted within the longitudinal axis of said syringe horizontal, said syringe being then rotatable about said mounting bosses so that said longitudinal axis of said syringe is positioned vertically and retained by said mounting means for operation of said syringe through repetitive fill and pump cycles; and

a flexible sealing cap overlying and encasing said piston head, said cap engaging said annular flanges and defining an upwardly directed conical piston face, the slope of said conical face 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 conical 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.

13. Apparatus as set forth in claim 12, wherein said cylinder, said piston head, and said piston rod are molded plastic.

14. Apparatus as set forth in claim 12, wherein said sealing cap is rubber.

15. Apparatus as set forth in claim 12, wherein said cylinder includes an integral tab for use as a handle in installing and removing said syringe cartridge from the syringe pump.

16. Apparatus as set forth in claim 12, 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.

17. Apparatus as set forth in claim 12, wherein said piston rod has a substantially H cross-section perpendicular to the longitudinal axis of said piston rod.

18. Apparatus as set forth in claim 12, wherein said piston rod includes a pair of parallel longitudinally extending flanges joined by an integral crossbar.

19. Apparatus as set forth in claim 12, wherein said annular flanges of said piston head are supported by a plurality of intersecting ribs.

20. Apparatus as set forth in claim 19, wherein said intersecting ribs intersect at the longitudinal axis of said piston head, the uppermost ends of said intersecting ribs being tapered to provide support for said conical face of said sealing cap.