Shape memory alloy wire driven positive displacement micropump with pulsatile output

An apparatus comprising:

• a gear engagement member comprising a shape memory wire, the 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 gear adapted to engage the gear engagement member;
• a fluid pump coupled to the gear such that when the gear is engaged with the gear engagement member and actuated, the fluid pump generates a fluid flow from the work stroke produced by the wire;
• and
• a fluid conduit adapted to couple the fluid pump to a fluid medication reservoir, wherein the gear engagement member comprises a pull that rotates the gear to generate fluid flow, and wherein the pull contacts and pulls on teeth on the gear to rotate the gear.

A fluid delivery system, comprising

• a reservoir;
• a fluid pump for 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 gear engagement member comprising a shape memory wire, the 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 and attains a memorized configuration such chat the wire can produce a work stroke as a consequence of a transition between the first and second material conditions;
• a gear adapted to engage the gear engagement member, wherein the gear engagement member is in direct contact with teeth on the gear and the fluid pump is coupled to the gear such that when the gear is engaged with the gear engagement member and actuated, the fluid pump generates a fluid flow from the work stoke produced by the wire;
• an enclosure housing the reservoir, gear, gear engagement member, pump and electronic circuit;
• and
• an infusion set directly coupled to the conduit.

A fluid delivery system, comprising

• a reservoir;
• a fluid pump for 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 gear engagement member comprising a shape memory wire, the 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 and 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 gear adapted to engage the gear engagement member, wherein the fluid pump is coupled to the gear such that when the gear is engaged with the gear engagement member and actuated, the fluid pump generates a fluid flow from the work stroke produced by the wire;
• an enclosure housing the reservoir, gear, gear engagement member, pump and electronic circuit;
• and
• an infusion set directly coupled to the conduit,
• wherein the gear engagement member comprises a pull that engages and rotates the gear to generate fluid flow, and wherein the pull contacts and pulls on teeth on the gear to rotate the gear.

A method of pumping fluid, comprising the steps of:

• subjecting a shape memory wire to a first material condition, wherein the wire comprises a gear engagement member and is 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, and wherein the wire and 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;
• and
• subjecting the wire to a second material condition,
• wherein a gear is coupled to a fluid pump and the gear engagement member is in direct contact with teeth on the gear such that when the gear is engaged with the gear engagement member and actuated, the fluid pump generates a fluid flow from the work stroke produced by the wire as a consequence of a transition between the first and second material conditions.

A method of pumping fluid, comprising the steps of:

• subjecting a shape memory wire to a first material condition, wherein the wire comprises a gear engagement member and is 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, and wherein the wire and 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;
• and
• subjecting the wire to a second material condition,
• wherein a gear is coupled to a fluid pump such that when the gear is engaged with the gear engagement member and actuated, the fluid pump generates a fluid flow from the work stroke produced by the wire as a consequence of a transition between the first and second material condition,
• wherein the gear engagement member comprises a pull that engages and rotates the gear to generate fluid flow, and wherein the pull contacts and pulls on teeth on the gear to rotate the gear.