Electrochemical controlled dispensing assembly and method

• US 5,368,571 A
• Filed: 02/01/1994
• Issued: 11/29/1994
• Est. Priority Date: 02/03/1993
• Status: Expired due to Fees

• Current Assignee: Pharmetrix Corporation
• Original Assignee: Pharmetrix Corporation
• Inventors: Horres, Charles R. Jr.
• Primary Examiner(s): Rosenbaum, C. Fred
• Assistant Examiner(s): Rafa, Michael
• Application Number:
  US08/190,639
• Time in Patent Office: 301 Days
• Field of Search: 128/DIG. 12, 128/DIG. 13, 128/898, 604/49, 604/51, 604/131, 604/133, 604/134, 604/140, 604/141, 604/890.1, 604/891.1
• US Class Current: 604/131
• CPC Class Codes: A61M 2205/0244 Micromachined materials, e.g. made from silicon wafers, microelectromechanical systems [MEMS] or comprising nanotechnology
• CPC Class Codes: A61M 5/14248 of the skin patch type
• CPC Class Codes: A61M 5/145 using pressurised reservoirs, e.g. pressurised by means of pistons
• CPC Class Codes: Y10S 128/12 Pressure infusion

Abstract

A pump assembly (20) employs electrochemistry to selectively control the delivery rate of a dispensing fluid (21) from a dispensing reservoir (24) by selectively controlling the flow rate of a driving fluid (19) from a driving reservoir (23) to a receiving reservoir (33). A partition (25), separating the driving reservoir from the receiving fluid reservoir, includes at least one aperture (28) which is opened or closed depending upon an electrical signal from a remote programming unit. Flow into the receiving reservoir deflects a barrier member to expel dispensing fluid from the dispensing reservoir. The dispensing fluid flow rate can be programmed to provide an appropriate steady or varying flow rate; user-initiated pulses of dispensing fluid can also be provided. A method of controlled infusion of an infusate employing electrochemistry is also provided.

Claims

1. A pump assembly for controlled delivery of a dispensing fluid comprising:

a partition having a front surface and an opposite facing back surface, and defining an aperture extending from said front surface to said back surface;

a driving reservoir formed for storing a driving fluid therein and in communication with said aperture for flow of said driving fluid through said partition;

plug means disposed in said aperture in a manner preventing flow of said driving fluid through said partition;

electric control means operably coupled to said plug means for controlling passage of said driving fluid through said aperture;

barrier means defining a receiving reservoir and positioned relative to said aperture for receipt and containment of said driving fluid in said receiving reservoir as said driving fluid flows from said driving reservoir through said aperture, said barrier means separating said dispensing fluid and said driving fluid, and further formed to expand from a first volume toward an increased second volume in response to receipt of said driving fluid in said receiving reservoir;

a dispensing reservoir for holding said dispensing fluid therein, said dispensing reservoir defining an orifice for release of said dispensing fluid therethrough, said barrier means being mounted for movement in said dispensing reservoir in a manner communicating with said dispensing fluid to urge said dispensing fluid through said orifice as said barrier means moves toward said increased second volume; and

means for temporarily increasing the flow of the driving fluid to the receiving reservoir so as to deliver a temporarily increased flow of the dispensing fluid through the orifice.

2. The pump assembly of claim 1 wherein the temporarily increasing flow means further comprises means for delivering a pulse of the driving fluid from the driving reservoir to the receiving reservoir so to deliver a pulse of the dispensing fluid through said orifice.

3. The pump assembly of claim 2 wherein the driving fluid pulse delivering means is a user-actuated means.

4. The pump assembly of claim 3 wherein the driving fluid pulse delivering means includes means for limiting the frequency of actuation thereof.