Shape memory alloy wire driven positive displacement micropump with pulsatile output
First Claim
1. An apparatus, comprising:
- a shape memory wire capable attaining at least two different material conditions, a first material condition below a transformation temperature and a second material condition above a transformation temperature, wherein the wire attains a memorized configuration such that the wire can produce a work stroke as a consequence of a transition between the first and second material conditions;
a spring biased against the wire to be deflected by the work stroke which deforms the wire from the memorized configuration when the wire attains the first material condition;
a reciprocating fluid pump coupled to the wire and driven by the biased spring and wire to produce a fluid flow; and
at least one fluid tube that couples the reciprocating fluid pump to a fluid medication reservoir;
wherein the shape memory wire has an extended effective length in a doubled back configuration.
1 Assignment
0 Petitions
Accused Products
Abstract
Apparatuses and methods for pumping fluid are disclosed. An exemplary apparatus is a miniature pump that includes a shape memory wire that obtains a plastic condition below a transformation temperature and has a memorized shape such that the shape memory wire produces a work stroke by returning to the memorize shape at least at the transformation temperature. A spring biased against the shape memory wire is deflected by the work stroke to deform the shape memory wire from the memorized shape below the transformation temperature. A fluid pump is coupled to the shape memory wire and driven by the biased spring and shape memory wire to produce a fluid flow. The miniature pump can be incorporated into a self-contained infusion device in the form of a compact self-adhesive patch including a fluid reservoir, control electronics and power supply that is place directly at the infusion site of a user.
-
Citations
72 Claims
-
1. An apparatus, comprising:
-
a shape memory wire capable attaining at least two different material conditions, a first material condition below a transformation temperature and a second material condition above a transformation temperature, wherein the wire attains a memorized configuration such that the wire can produce a work stroke as a consequence of a transition between the first and second material conditions; a spring biased against the wire to be deflected by the work stroke which deforms the wire from the memorized configuration when the wire attains the first material condition; a reciprocating fluid pump coupled to the wire and driven by the biased spring and wire to produce a fluid flow; and at least one fluid tube that couples the reciprocating fluid pump to a fluid medication reservoir; wherein the shape memory wire has an extended effective length in a doubled back configuration. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19)
-
-
20. A fluid delivery system, comprising
a reservoir; -
a miniature pump receiving a fluid from the reservoir and driving the fluid our a conduit; an electronic circuit for controlling delivery of the fluid with the pump; a compact shell enclosure housing the reservoir, pump and electronic circuit; and an infusion set directly coupled to the conduit; wherein the compact shell enclosure can be coupled directly to an infusion site of a user for medication delivery through the infusion set and wherein the miniature pump is in a cylindrical form smaller than approximately 25 mm in diameter and 25 mm long. - View Dependent Claims (21, 22, 23, 24, 25, 26, 27, 28)
-
-
29. A fluid delivery system, comprising:
-
a reservoir, a miniature pump receiving a fluid from the reservoir and driving the fluid out a conduit; an electronic circuit for controlling delivery of the fluid with the pump; a compact shell enclosure housing the reservoir, pump and electronic circuit; and an infusion set directly coupled to the conduit; wherein the compact shell enclosure can be coupled directly to an infusion site of a user for medication delivery through the infusion set, wherein the pump is actuated by a shape memory wire that obtains a plastic condition below a transformation temperature and has a memorized shape such that the wire produces a work stroke by substantially returning to the memorized shape at and above the transformation temperature and wherein a spring is biased against the wire to be deflected by the work stroke and the spring deforms the wire in the plastic condition from the memorized shape and wherein the shape memory wire has an extended effective length in a doubled back configuration. - View Dependent Claims (30, 31, 32)
-
-
33. A fluid delivery system, comprising:
-
a reservoir; a miniature pump receiving a fluid from the reservoir and driving the fluid our a conduit; an electronic circuit for controlling delivery of the fluid with the pump; a compact shell enclosure housing the reservoir, pump and electronic circuit; and an infusion set directly coupled to the conduit; wherein the compact shell enclosure can be coupled directly to an infusion site of a user for medication delivery through the infusion set, wherein the pump is actuated by a shape memory wire that obtains a plastic condition below a transformation temperature and has a memorized shape such that the wire produces a work stroke by substantially returning to the memorized shape at and above the transformation temperature and wherein a spring is biased against the wire to be deflected by the work stroke and the spring deforms the wire in the plastic condition from the memorized shape and wherein the pump includes a valved chamber and a piston, wherein the valved chamber expands and contracts with movement of the piston. - View Dependent Claims (34, 35, 36, 37, 38, 39, 40, 41, 42)
-
-
43. A method of pumping fluid, comprising the steps of
heating an shape memory wire to a recovery temperature equal or greater than a transformation temperature of the shape memory wire; -
returning the shape memory wire to a memorized shape, overcoming the bias spring and drawing fluid from a medication reservoir into a valved chamber at the recovery temperature; cooling the shape memory wire to a reset temperature below the transformation temperature; and deforming the shape memory wire and driving the fluid out of the valved chamber below the reset temperature with the bias spring. - View Dependent Claims (44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57)
-
-
58. A method of pumping medication fluid, comprising the steps of:
-
using a bias spring to deform a shape memory wire coupled to a valved chamber so that fluid is drawn from a medication reservoir into the valved chamber at a reset temperature below the transformation temperature of the shape memory wire; heating the shape memory wire to a recovery temperature equal or greater than the transformation temperature; returning the shape memory wire to a memorized shape at the recovery temperature, overcoming the bias spring and driving fluid out of the valved chamber; and allowing the shape memory wire to return to the reset temperature. - View Dependent Claims (59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72)
-
Specification