Surgical generator method for controlling and ultrasonic transducer waveform for ultrasonic and electrosurgical devices

• US 10,265,117 B2
• Filed: 05/18/2015
• Issued: 04/23/2019
• Est. Priority Date: 10/09/2009
• Status: Active Grant

• Current Assignee: Cilag Gmbh International (Johnson & Johnson)
• Original Assignee: Ethicon, LLC (Johnson & Johnson)
• Inventors: Wiener, Eitan T., Aldridge, Jeffrey L., Giordano, James R., Stulen, Foster B., Brotz, Joseph A., Hein, John E.
• Primary Examiner(s): Layno, Carl H
• Assistant Examiner(s): Ghand, Jennifer
• Application Number:
  US14/715,305
• Publication Number:
  US 20150340586A1
• Time in Patent Office: 1,436 Days
• CPC Class Codes: A61B 18/1206 Generators therefor
• CPC Class Codes: A61B 18/1233 with circuits for assuring patient safety
• CPC Class Codes: A61B 18/14 Probes or electrodes therefor
• CPC Class Codes: A61B 18/1445 at the distal end of a shaft, e.g. forceps or scissors at the end of a rigid rod
• CPC Class Codes: A61B 2017/00017 Electrical control of surgical instruments
• CPC Class Codes: A61B 2017/00477 Coupling A61B2017/0046 takes precedence
• CPC Class Codes: A61B 2017/00482 with a code
• CPC Class Codes: A61B 2017/00486 Adaptors for coupling parts with incompatible geometries
• CPC Class Codes: A61B 2017/2934 arcuate shaped guiding means
• CPC Class Codes: A61B 2017/2936 Pins in guiding slots
• CPC Class Codes: A61B 2017/320069 for ablating tissue
• CPC Class Codes: A61B 2017/320071 with articulating means for working tip
• CPC Class Codes: A61B 2017/320094 additional movable means performing clamping operation
• CPC Class Codes: A61B 2017/320095 with sealing or cauterizing means
• CPC Class Codes: A61B 2018/00178 Electrical connectors
• CPC Class Codes: A61B 2018/00601 Cutting
• CPC Class Codes: A61B 2018/0063 Sealing
• CPC Class Codes: A61B 2018/00666 using a threshold value
• CPC Class Codes: A61B 2018/00678 upper
• CPC Class Codes: A61B 2018/00684 using lookup tables
• CPC Class Codes: A61B 2018/00702 : Power or energy
• CPC Class Codes: A61B 2018/0072 : Current
• CPC Class Codes: A61B 2018/00732 : Frequency
• CPC Class Codes: A61B 2018/00767 : Voltage
• CPC Class Codes: A61B 2018/00779 : Power or energy
• CPC Class Codes: A61B 2018/00803 : with temperature prediction
• CPC Class Codes: A61B 2018/00827 : Current
• CPC Class Codes: A61B 2018/00875 : Resistance or impedance
• CPC Class Codes: A61B 2018/00892 : Voltage
• CPC Class Codes: A61B 2018/00988 : Means for storing information, e.g. calibration constants, or for preventing excessive use, e.g. usage, service life counter
• CPC Class Codes: A61B 2018/00994 : combining two or more different kinds of non-mechanical energy or combining one or more non-mechanical energies with ultrasound
• CPC Class Codes: H01R 2201/12 : for medicine and surgery
• CPC Class Codes: H10N 30/802 : Drive or control circuitry or methods for piezoelectric or electrostrictive devices not otherwise provided for

Abstract

A method for controlling a waveform shape of a motional branch current in an ultrasonic transducer of a surgical device. The method may comprise generating a transducer drive signal by selectively recalling, using a direct digital synthesis (DDS) algorithm, drive signal waveform samples stored in a look-up table (LUT), generating samples of current and voltage of the transducer drive signal when the transducer drive signal is communicated to the surgical device, determining samples of the motional branch current based on the current and voltage samples, a static capacitance of the ultrasonic transducer and a frequency of the transducer drive signal, comparing each sample of the motional branch current to a respective target sample of a target waveform to determine an error amplitude, and modifying the drive signal waveform samples stored in the LUT such that an amplitude error between subsequent samples of the motional branch current and respective target samples is reduced.

Claims

1. A method for controlling a waveform property of a motional branch current in an ultrasonic transducer of a surgical device, the method comprising:

generating a transducer drive signal by selectively recalling, using a direct digital synthesis (DDS) algorithm, drive signal waveform samples stored in a look-up table (LUT);

generating samples of current and voltage of the transducer drive signal when the transducer drive signal is communicated to the surgical device;

determining samples of the motional branch current based on the current and voltage samples of the transducer drive signal, a static capacitance of the ultrasonic transducer and a frequency of the transducer drive signal;

comparing each sample of the motional branch current to a respective target sample of a target waveform to determine an error amplitude; and

modifying the drive signal waveform samples stored in the LUT such that an amplitude error between subsequent samples of the motional branch current and respective target samples is reduced.

2. The method of claim 1, wherein the waveform property comprises a waveform amplitude.

3. The method of claim 2, wherein the target waveform comprises a sinusoid waveform.

4. The method of claim 2, wherein the target waveform comprises at least two superimposed waveforms.

5. The method of claim 4, wherein the target waveform comprises a sinusoid waveform superimposed with an n-order harmonic of the sinusoid waveform, wherein n is a positive integer.

6. The method of claim 1, wherein the waveform property comprises a waveform frequency.

7. The method of claim 6, wherein the target waveform comprises a sinusoid waveform.

8. The method of claim 6, wherein the target waveform comprises at least two superimposed waveforms.

9. The method of claim 8, wherein the target waveform comprises a sinusoid waveform superimposed with an n-order harmonic of the sinusoid waveform, wherein n is a positive integer.

10. The method of claim 1, wherein the LUT comprises a dynamically-updated look-up table.

11. The method of claim 1, wherein the waveform property is a waveform shape.