Liquid delivery device bladder

• US 3,993,069 A
• Filed: 08/18/1975
• Issued: 11/23/1976
• Est. Priority Date: 03/26/1973
• Status: Expired due to Term

• Current Assignee: ALZA Corporation (Johnson & Johnson)
• Original Assignee: ALZA Corporation (Johnson & Johnson)
• Inventors: Yum, Su Il, Michaels, Alan S., Leeper, Harold M., Buckles, Richard G.
• Primary Examiner(s): Pellegrino, Stephen C.
• Application Number:
  US05/605,690
• Time in Patent Office: 463 Days
• Field of Search: 128/213, 128/214 F, 128/216, 128/DIG. 12, 222/386.5, 222/215, 222/94, 222/212, 222/107, 222/206, 222/95, 220/63 R, 220/85 B, 260/79.5 A, 260/79.5 B, 46/87
• US Class Current: 604/132
• CPC Class Codes: A61J 1/05 for collecting, storing or administering blood, plasma or medical fluids multiple bags systems for separating or storing blood components A61M1/0209; Infusion or perfusion containers
• CPC Class Codes: A61M 5/152 pressurised by contraction of elastic reservoirs containers for dispensing contents by contraction of an elastic bag provided therein, in general B65D83/0061
• CPC Class Codes: B65D 83/0061 the contents of a flexible bag being expelled by the contracting forces inherent in the bag or a sleeve fitting snugly around the bag
• CPC Class Codes: Y10S 128/12 Pressure infusion

Abstract

An improvement in liquid dispensers, especially those used to infuse liquid drugs into patients from an expansible elastomeric bladder of specific geometry and elastomeric properties, is disclosed. The improvement is in making the bladder from an elastomeric composition whose stress relaxation does not exceed 10%, and whose low frequency hysteresis does not exceed 10%.

Claims

1. In a liquid dispensing apparatus comprising in combination a housing, an expansible elastomeric bladder contained within the housing for holding the liquid under pressure, the elastic force in the bladder walls providing the force by which the liquid is dispensed from the apparatus, a liquid flow passageway extending from the bladder to a dispensing site and valve means associated with the passageway for regulating the flow of liquid through the passageway, said bladder being cylindrical, having a deflated length that is not less than 5 times its deflated inside diameter, walls whose thickness is from about 0.01 to about 1 times the deflated inside diameter of the bladder, and an axial stress at 300% elongation that is not more than 1.5 times the radial stress at 300% elongation, and being formed from an elastomeric composition that has a permanent set of less than about 3% and that has a uniaxial stress/strain curve that has an ultimate elongation exceeding 400%, and a point in the range of 300% and 1000% elongation at which the slope increases significantly, the improvement wherein the elastomeric composition has a stress relaxation that does not exceed about 10% and a low frequency hysteresis that does not exceed about 10%.

2. The liquid storing and dispensing apparatus of claim 1 including the further improvement wherein the bladder is contained within the housing in a manner in which the bladder is substantially unrestricted in its deflated and inflated states.

3. The liquid storing and dispensing apparatus of claim 1 wherein the thickness of the bladder walls is from 0.1 to 0.5 times the deflated inside diameter of the bladder.

4. In an apparatus for infusing liquid drug under pressure into a patient comprising in combination a housing, an expansible elastomeric bladder contained within the housing for holding the liquid drug under pressure, the elastic force in the bladder walls providing the force by which the liquid drug is infused, a liquid drug passageway extending from the bladder to the infusion site and valve means associated with the passageway for regulating the flow of liquid drug through the passageway, said bladder being cylindrical, having a deflated length that is not less than 5 times its deflated inside diameter, walls whose thickness is from about 0.01 to about 1 times the deflated inside diameter of the bladder, and an axial stress at 300% elongation that is not more than 1.5 times the radial stress at 300% elongation, and being formed from an elastomeric composition that has a permanent set of less than about 3% and that has a uniaxial stress/strain curve that has a stress exceeding 50 psi at 300% elongation, an ultimate elongation exceeding 400%, and a point in the range of 300% and 1000% elongation at which the slope increases significantly, the improvement wherein the elastomeric composition has a stress relaxation that does not exceed about 10% and a low frequency hysteresis that does not exceed about 10%.

5. The apparatus of claim 4 including the further improvement wherein the bladder is contained within the housing in a manner in which the bladder is substantially unrestricted in its deflated and inflated states.

6. The apparatus of claim 4 wherein the thickness of the bladder walls is from 0.1 to 0.5 times the deflated inside diameter of the bladder.