INTRAVENOUS DELIVERY PUMP

• US 3,874,826 A
• Filed: 01/08/1974
• Issued: 04/01/1975
• Est. Priority Date: 02/05/1973
• Status: Expired due to Term

• Current Assignee: Ingemar H. Lundquist
• Original Assignee: Ingemar H. Lundquist
• Inventors: Lundquist, Ingemar H.
• Primary Examiner(s): Freeh, William L.
• Application Number:
  US05/431,753
• Time in Patent Office: 448 Days
• Field of Search: 74/18,18.1,18.2 184/24 417/221.5,507,536,568,565,559,127 128/214F,273,214C,235 132/527 222/319,377,380,373
• US Class Current: 417/565
• CPC Class Codes: A61M 5/14224 Diaphragm type
• CPC Class Codes: F04B 53/00 Component parts, details or accessories not provided for in, or of interest apart from, groups F04B1/00 - F04B23/00 or F04B39/00 - F04B47/00
• CPC Class Codes: F04B 53/10 Valves; Arrangement of valves
• CPC Class Codes: F04B 53/143 Sealing provided on the piston
• CPC Class Codes: F16K 31/22 with the float rigidly connected to the valve
• CPC Class Codes: Y10S 128/12 Pressure infusion

Abstract

The present invention comprises a small, precise measuring pump provided with a germ barrier that is specifically designed for intravenous feeding devices and comprises: inlet and outlet chambers which are preferably integral one with the other, an inlet adapted to receive a tube from a storage device and the outlet chamber provided with an outlet adapted to receive a tube for delivery of material pumped to a patient; a passageway between the two chambers, which serves as an outlet from the inlet chamber and an inlet into the outlet chamber; a valve (preferably a float valve) associated with each inlet; and an actuating device which includes a piston and a tightly fitting resilient sheath enclosing the piston, the combination of piston and sheath projecting into the inlet chamber. The movement of the piston inwardly and outwardly within the inlet chamber provides the pumping force for the operation of the pump, and the sheath provides a sterile seal between the piston and the body of the pump and also, if made of resilient material, such as rubber, provides a force for returning the piston to an inoperative position. A pumping force may be applied to the external end of the piston by any suitable means.

Claims

1. A small, precise measuring pump having a germ barrier comprising:

a. a non-deformable inlet chamber and an outlet chamber attached thereto;

b. an inlet into said inlet chamber and a communication duct from said inlet chamber into said outlet chamber;

c. a valve in said inlet chamber cooperating with said inlet and a valve in said outlet chamber cooperating with said communication duct;

d. an outlet from said outlet chamber;

e. a piston having an inner end section projecting through the wall of said inlet chamber and adapted to be moved inwardly and outwardly therein, said piston having an exposed outer end portion which remains outside said chamber and is adapted for engagement by a piston actuating means;

f. a resilient sheath entirely enclosing the portion of said piston which is inside said inlet chamber and having means external to the inlet chamber for sealing engagement with the outer wall of the inlet chamber and further means external of the inlet chamber for sealing engagement with the outer surface of said piston.

2. A disposable intravenous liquid pump adapted for delivering a sterile liquid at a variable controlled rate comprising:

a. a pump chamber having an inlet duct and an outlet duct;

b. a valve cooperating with each said inlet and outlet ducts;

c. a displacement piston having an inner end portion projecting inwardly through a walL of said pump chamber adapted to be moved from an inoperative position inwardly and outwardly therein within variable controlled limits, said piston having an exposed outer end portion which remains outside said chamber with the said outer end thereof adapted for engagement by a piston actuating means;

d. a flexible sheath having the interior surface throughout the length thereof disposed in contact with the outer surface of said inner end portion of said piston, and said sheath having the outer end thereof in sealing engagement with said wall of said pump chamber; and

e. sealing means preventing the admission of air between said piston and said sheath comprising an inwardly extending lip on said sheath tightly engaging the outer surface of the piston and normally having an internal diameter which is less than that of said outer surface.

3. An apparatus as in claim 2 wherein said flexible sheath exerts a force on said piston in an axially outwardly direction when said piston is moved by a said piston actuating means from an inoperative position axially inwardly within the interior of said chamber, and said force being sufficient to effect movement of said piston outwardly to said inoperative position when said piston actuating means ceases to apply an axially inwardly force to said piston.

4. The apparatus of claim 2 wherein the sheath is thicker at the end of said piston than along the side wall thereof.

5. An intravenous delivery pump comprising:

a. a spherical inlet chamber and an outlet chamber attached thereto;

b. an inlet projecting inwardly into said inlet chamber and a communication duct from said inlet chamber projecting into said outlet chamber;

c. a float valve in said inlet chamber cooperating with said inlet and a float valve in said outlet chamber cooperating with said communication duct;

d. an outlet from said outlet chamber;

e. a piston projecting through the wall of said spherical inlet chamber and adapted to be moved inwardly and outwardly therein;

f. a resilient sheath tightly enclosing said piston, the outer end of said sheath being in sealing engagement with the wall of said spherical inlet chamber and the inner end thereof entirely enclosing the piston.

6. The apparatus of claim 5 wherein the sheath is provided with an inner lip at the open outer end thereof adapted to tightly engage the piston, and the end wall of said sheath is thicker than the side wall thereof.

7. The apparatus of claim 5 wherein the valve for said inlet and said intermediate duct comprises a float, an arm attached to said float, said arm being pivotally mounted in a wall of the respective chamber and said arm carrying a sealing gasket adapted to engage the end of said inlet or the said intermediate duct, respectively.

8. The apparatus of claim 5 wherein the inlet into said inlet chamber projects inwardly in said chamber and terminates at a central elevation.

9. The apparatus of claim 5 comprising also a lubricant between the sheath and the piston.