Implantable electromagnetic pumps

1 . A micropump implantable in an eye, comprising:

a ferromagnetic member;

a power source;

a motor coil magnetically coupled to the ferromagnetic member and electrically coupled to the power source to receive power from the power source, wherein the motor coil is configured to generate a magnetic field in the ferromagnetic member when power is applied to the motor coil by the power source;

a housing enclosing the motor coil and the power source and partially enclosing the ferromagnetic member, wherein the housing is hermetically sealed;

a pump diaphragm;

a compression chamber at least partially defined by the pump diaphragm and having an inlet and an outlet;

an armature configured to move in response to the magnetic field in the ferromagnetic member; and

wherein the pump diaphragm is configured to cause fluid to flow through the compression chamber from the inlet to the outlet in response to movement of the armature, and wherein the pump diaphragm, the compression chamber, the armature, and a portion of the ferromagnetic member are located outside of the housing.

2 . The micropump of claim 1 , wherein the portion of the ferromagnetic member defines part of an expansion chamber, and wherein the expansion chamber encloses the spring and the armature.

3 . The micropump of claim 1 , further comprising:

an opening in the ferromagnetic member through which fluid may flow into the expansion chamber responsive to actuation of the pump diaphragm.

4 . The micropump of claim 1 , further comprising a spring having a first end and a second end opposite the first end, wherein the armature comprises a first side and a second side opposing the first side, wherein the first end is connected to the housing and the second end is connected to the first side of the armature, and wherein the second side of the armature is configured to drive the pump diaphragm.

5 . The micropump of claim 4 , wherein the pump further includes:

a first one-way valve that prevents fluid from flowing from the outlet to the chamber; and

a second one-way valve that prevents fluid from flowing from the chamber to the inlet.

6 . The micropump of claim 1 , wherein the power source is a battery or a capacitor.

7 . The micropump of claim 1 , wherein the ferromagnetic member extends through the housing such that the portion of the ferromagnetic member is located outside of the housing.

8 . The micropump of claim 1 , further comprising:

an inlet valve chamber in fluid communication with the compression chamber, wherein the inlet valve chamber is at least partially defined by the pump diaphragm;

an outlet valve chamber in fluid communication with the compression chamber, wherein the inlet valve chamber is at least partially defined by the pump diaphragm;

a plunger;

a second plunger; and

a third plunger,

wherein the plunger is configured to actuate the pump diaphragm to selectively block and unblock the compression chamber, the second plunger is configured to actuate the pump diaphragm to selectively block and unblock the inlet valve chamber, and the third plunger is configured to configured to actuate the pump diaphragm to selectively block and unblock the outlet valve chamber to effectuate fluid flow into the inlet valve chamber through the compression chamber and out of the outlet valve chamber.

9 . An implantable micropump, comprising:

a ferromagnetic core;

a coil comprising multiple windings around the ferromagnetic core;

a ferromagnetic member connected to the ferromagnetic core;

a power source coupled to the coil and configured to provide power to the coil, wherein the coil is configured to generate a magnetic field in the ferromagnetic core and the ferromagnetic member in response to the power source providing power to the coil;

a housing enclosing the coil and the power source and partially enclosing the ferromagnetic member, wherein the housing is impervious, and wherein a portion of the ferromagnetic member extends through the housing; and

an armature configured to move in response to the magnetic field in the ferromagnetic member and configured to cause fluid to flow through the implantable micropump.

10 . The implantable micropump of claim 9 , further comprising:

a plunger, wherein the armature includes an opening through which the plunger passes; and

a spring coupled to the armature and configured to axially translate the plunger through the opening in the armature in response to rotation of the armature.

11 . The implantable micropump of claim 10 , further comprising:

a diaphragm, wherein the plunger is configured to actuate the diaphragm causing the diaphragm to move fluid.

12 . The implantable micropump of claim 9 , further comprising:

an integrated circuit configured to control the power provided by the power source to the coil.

13 . The implantable micropump of claim 9 , further comprising:

an integrated circuit that controls the power to the coil; and

a pressure sensor that sends pressure readings to the integrated circuit, wherein the integrated determines when to power the coil based on the pressure readings.

14 . The implantable micropump of claim 9 , wherein the armature includes at least one slot.

15 . The implantable micropump of claim 9 ,

wherein ferromagnetic core is a first ferromagnetic core and the coil is a first coil, and

wherein the implantable micropump further includes:

a second ferromagnetic core; and

a second coil, including multiple windings around the second ferromagnetic core, wherein the second ferromagnetic core is connected to the ferromagnetic member.