Liquid delivery device particularly useful for delivering drugs

• US 5,242,406 A
• Filed: 12/16/1991
• Issued: 09/07/1993
• Est. Priority Date: 10/19/1990
• Status: Expired due to Term

• Current Assignee: Elan Pharma International Limited (Perrigo Company PLC)
• Original Assignee: Sil Medics Ltd.
• Inventors: Zucker, Shlomo, Gross, Joseph
• Primary Examiner(s): Green, Randall L.
• Assistant Examiner(s): GUALTIERI, GINA
• Application Number:
  US07/809,195
• Time in Patent Office: 631 Days
• Field of Search: 604/132-134, 604/891.1, 604/135-148, 604/153, 128/DIG. 12, 222/95, 222/491, 222/494, 222/386.5
• US Class Current: 604/132
• CPC Class Codes: A61M 2005/14204 with gas-producing electrochemical cell
• CPC Class Codes: A61M 5/155 pressurised by gas introduced into the reservoir
• CPC Class Codes: A61M 5/16881 Regulating valves on-off valves, e.g. clamps A61M39/28
• CPC Class Codes: B05B 11/027 inverted during outflow of content
• CPC Class Codes: B05B 9/0844 the container being pressurised or compressed by a gas generated by a chemical reaction
• CPC Class Codes: Y10S 128/12 Pressure infusion

Abstract

A delivery device for delivering a liquid containing a drug includes a first diaphragm within a housing defining a first contractible-chamber on one side of the diaphragm for holding a supply of the liquid to be delivered, and a second contractible chamber on the opposite side of the diaphragm including an electrolytic cell capable of generating a gas according to the electrical current passed through the cell electrolyte. The device further includes a second diaphragm, a control valve, and a spring, for compensating the rate of delivery of the liquid for variations in ambient pressure and temperature.

Claims

1. A liquid delivery device including:

an outer housing having an outlet for a liquid to be delivered;

a displaceable member within the housing defining a first contractible chamber on one side of the displacement member for holding a supply of the liquid to be delivered, and a second contractible chamber on an opposite side of the displaceable member in which a pressure is to be produced for controlling the displacement of the displacement member, and thereby the rate of flow of the liquid via said outlet;

and pressure control means for controlling the pressure produced in said second contractible chamber;

characterized in that said housing further includes;

a second displaceable member defining a third contractible chamber between said housing and said first contractible chamber adjacent to said outlet;

said third contractible chamber including compensating means for compensating the rate of flow of the liquid via said outlet in response to changes in temperature and pressure.

2. The device according to claim 1, wherein said compensating means comprises:

a second valve between said displaceable member and said housing outlet;

and biassing means for biassing said second displaceable member in a direction tending to close said control valve, such as to compensate the rate of flow of the liquid via the outlet for variations in ambient pressure and temperature.

3. The device according to claim 2, wherein both of said displaceable members are diaphragms, and said pressure control means comprises an electrolytic cell having a pair of electrodes separated by an electrolyte capable of generating a gas applied to said second chamber according to electrical current passing through said electrolyte.

4. The device according to claim 3, wherein the cross sectional area of the second diaphragm is many times greater than that of an outlet side of said control valve,

5. The device according to claim 2, wherein said housing includes venting means between said control valve and said outlet.

6. The device according to claim 3, wherein said third chamber includes electrical sensor means for sensing the opening of said control valve.

7. The device according to claim 6, wherein said sensor means comprises a valve member and a valve seat both carried by said second diaphragm;

said valve seat having a lost-motion connection with respect to said valve member such that the valve member is normally closed with respect to the valve seat, but upon engagement of the second diaphragm with a fixed part of the housing, the valve member moves with respect to the valve seat to open the valve to said outlet;

and electrical means for sensing the engagement of the valve member with respect to said fixed part of the housing.

8. The device according to claim 7, wherein said lost-motion connection comprises a stem carried by said second diaphragm and engageable on one side thereof with said fixed part of the housing, said valve member also being carried by said second diaphragm;

said stem being displaceable with respect to said second diaphragm and carrying the valve seat on an opposite side of said second diaphragm.

9. The device according to claim 7, wherein said fixed part of the housing includes a pressure-sensor sensing the pressure applied by said stem against the fixed part of the housing.

10. The device according to claim 8, further including calibrating means for precalibrating the pressure required in said second chamber for opening said control valve.

11. The device according to claim 10, wherein said calibrating means comprises a rotatable member rotatably carried by said housing and having an inclined surface engageable with said stem carried by said second diaphragm.

12. The device according to claim 10, wherein said calibrating means comprises a leaf spring fixed at its opposite ends to the housing, and a threaded pin threaded through an opening in said housing and engageable with an intermediate portion of the leaf spring to move said intermediate portion towards or away from said opening in the housing.

13. The device according to claim 1, wherein said second chamber comprises a drug injection port for injecting a drug into said second chamber, and a vent permeable to air but not to liquid to permit priming the device.

14. The device according to claim 3, wherein the housing includes first, second and third section attachable together;

said first section including said outlet and being attachable to one side of said second section, with one diaphragm clamped therebetween;

the other side of said second section being attachable to said third section with the other diaphragm clamped therebetween.

15. The device according to claim 1, wherein said housing includes means for attaching the housing to a wrist of a user.

16. The device according to claim 3, wherein said housing includes an electronic control for controlling the time and magnitude of the electrical current passing through said electrolyte.