Harvesting energy from a surgical generator

1. A surgical device for use with a surgical generator, the surgical device comprising:

an energy storage device, the energy storage device in electrical communication with a surgical generator connection to provide energy from a surgical generator to charge the energy storage device and in electrical communication with at least one load component to be powered by the energy storage device;

an end effector;

at least one energy element for treating tissue, wherein the at least one energy element is in electrical communication with the surgical generator connection to provide a therapeutic drive signal to the at least one energy element; and

a signal separator circuit positioned between the surgical generator connection and the energy storage device and between the surgical generator connection and the at least one energy element, wherein the signal separator circuit is configured to receive a combined signal and divide the combined signal into a charge signal portion that is directed to the energy storage device and a therapeutic drive signal portion that is directed towards the at least one energy element, wherein the therapeutic drive signal portion is configured to provide electrical energy to the tissue sufficient for treating the tissue, wherein the surgical device is configured to direct the charge signal portion to the energy storage device and the therapeutic drive signal portion to the at least one energy element simultaneously,

wherein the charge signal portion and the therapeutic drive signal portion are present in the combined signal at different frequencies or phases.

2. The surgical device of claim 1 , wherein the energy storage device comprises at least one capacitor.

3. The surgical device of claim 1 , wherein the energy storage device comprises at least one battery.

4. The surgical device of claim 1 , wherein the signal separator circuit comprises at least one of a rectifier and a frequency-dependent filter.

5. The surgical device of claim 1 , further comprising a memory circuit storing information describing the surgical device, wherein the information comprises an indication that the surgical device is configured to harvest energy from a surgical generator.

6. The surgical device of claim 1 , wherein the at least one energy element comprises at least one of the group consisting of: at least one electrode positioned at the end effector; and an ultrasonic transducer.

7. The surgical device of claim 1 , wherein the energy storage device is positioned in at least one location selected from the group consisting of: integral to the surgical device; and external to the surgical device.

8. The surgical device of claim 7 , wherein the surgical device is programmed to request, from the surgical generator, an ultrasonic drive signal to drive an ultrasonic transducer and, alternately, requesting, from the surgical generator, a charge signal to charge the energy storage device.

9. The surgical device of claim 1 , further comprising a charge management circuit configured to monitor a level of charge on the energy storage device.

10. The surgical device of claim 6 , wherein the surgical device further comprises an ultrasonic waveguide and an ultrasonic blade in mechanical communication with the ultrasonic transducer.

11. A surgical system comprising:

a surgical generator; and

a surgical device comprising:

an energy storage device, the energy storage device in electrical communication with a surgical generator connection to provide energy from the surgical generator to charge the energy storage device and in electrical communication with at least one load component to be powered by the energy storage device;

an end effector;

at least one energy element for treating tissue, wherein the at least one energy element is in electrical communication with the surgical generator connection to provide a therapeutic drive signal to the at least one energy element; and

a signal separator circuit positioned between the surgical generator connection and the energy storage device and between the surgical generator connection and the at least one energy element, wherein the signal separator circuit is configured to receive a combined signal and divide the combined signal into a charge signal portion that is directed to the energy storage device and a therapeutic drive signal portion that is directed towards the at least one energy element, wherein the therapeutic drive signal portion is configured to provide electrical energy to the tissue sufficient for treating the tissue, wherein the surgical device is configured to direct the charge signal portion to the energy storage device and the therapeutic drive signal portion to the at least one energy element simultaneously, wherein the charge signal portion and the therapeutic drive signal portion are present in the combined signal at different frequencies or phases,

wherein the surgical generator is configured to modify the combined signal to remove either the therapeutic drive signal portion or the charge signal portion from the combined signal.

12. The surgical system of claim 11 , wherein the signal separator circuit comprises at least one of a rectifier and a frequency-dependent filter.

13. The surgical system of claim 11 , wherein the at least one energy element comprises at least one of the group consisting of: at least one electrode positioned at the end effector; and an ultrasonic transducer.