Methods and apparatus for pumping coolant to an energy delivery device

1. A method for treating tissue beneath a skin surface with electromagnetic energy, the method comprising:

pumping a fluid from a container to an energy delivery device configured to emit the electromagnetic energy, wherein the container is coupled with a manifold and a pressure sensor is tapped into the manifold;

heating the fluid inside the container to a selected temperature, wherein the fluid is maintained in a liquid state inside the container; and

providing closed-loop control over the heating of the fluid based on pressure readings from the pressure sensor.

2. The method of claim 1 wherein the fluid is pumped from the container to the energy delivery device using a diaphragm pump.

3. The method of claim 2 wherein the fluid is pumped from the container to the energy delivery device using a first line upstream of the diaphragm pump and a second line downstream of the diaphragm pump, the first line is at a first pressure, and the second line is at a second pressure.

4. The method of claim 3 wherein the first pressure is in a range from about 50 psi to about 80 psi, and the second pressure is in range from about 110 psi to about 130 psi.

5. The method of claim 3 wherein the second pressure is greater than the first pressure.

6. The method of claim 1 wherein the fluid is pumped from the container to the energy delivery device using a diaphragm pump, the diaphragm pump is coupled to the container by a fluid line, and the fluid is also maintained under pressure in a liquid state inside the fluid line.

7. The method of claim 1 wherein the fluid is a coolant.

8. The method of claim 7 wherein the energy delivery device includes an electrode, and further comprising:

delivering a spray of the coolant from a nozzle onto the electrode.

9. The method of claim 1 further comprising:

delivering the electromagnetic energy from the energy delivery device to treat the tissue beneath the skin surface.

10. An apparatus for treating tissue beneath a skin surface with electromagnetic energy, the apparatus comprising:

a heater;

a container configured to hold a coolant, the container at least partially enclosed in the heater;

an energy delivery device configured to deliver the electromagnetic energy to the tissue;

a manifold coupling the container with a fluid line;

a cooling system including a pump configured to pump the coolant to the energy delivery device, the pump coupled to the container by the fluid line;

a system controller communicatively coupled to the energy delivery device and to the cooling system, the system controller programmed to control operation of the pump and the heater to maintain the coolant in a liquid state inside the container; and

a pressure sensor communicatively coupled to the system controller, the pressure sensor coupled with the manifold, and the pressure sensor tapped into the manifold,

wherein the system controller is configured to control the operation of the heater and the pump based on pressure readings from the pressure sensor.

11. The apparatus of claim 10 wherein the system controller is programmed to control the operation of the heater and the pump to maintain the coolant in the liquid state inside the fluid line.

12. The apparatus of claim 10 wherein the energy delivery device includes an electrode, a nozzle, and a control valve configured to control delivery of the coolant from the nozzle to the electrode.

13. The apparatus of claim 12 wherein the pump is a diaphragm pump.

14. The apparatus of claim 13 further comprising:

a manifold arranged between the pump and the control valve, the manifold including an arrestor configured to respond to pressure surges from operation of the diaphragm pump.

15. The apparatus of claim 12 wherein the energy delivery device is configured to emit the electromagnetic energy from the electrode.

16. The apparatus of claim 10 further comprising:

a first check valve in the fluid line.

17. The apparatus of claim 16 further comprising:

a second check valve in the fluid line.

18. The apparatus of claim 14 further comprising:

a check valve in the fluid line.