System and method for improved start-up of self-oscillating electro-mechanical surgical devices

• US 8,665,031 B2
• Filed: 08/29/2012
• Issued: 03/04/2014
• Est. Priority Date: 03/30/2010
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Covidien LP (Medtronic Plc)
• Inventors: Gilbert, James A.
• Primary Examiner(s): Gannon, Levi
• Application Number:
  US13/597,823
• Publication Number:
  US 20120319791A1
• Time in Patent Office: 552 Days
• Field of Search: 310/318, 327/143, 327/164, 331/34, 331/78, 331/116.FE, 331/116.M, 331/116.R, 331/154, 331/158, 331/160, 331/172, 331/173, 331/185, 600/437, 606/169, 708/250, 708/251, 708/255
• US Class Current: 331/154
• CPC Class Codes: A61B 17/320092 with additional movable means for clamping or cutting tissue, e.g. with a pivoting jaw
• CPC Class Codes: A61B 2017/00017 Electrical control of surgical instruments
• CPC Class Codes: A61B 2017/0015 applied simultaneously
• CPC Class Codes: A61B 2017/320093 additional movable means performing cutting operation
• CPC Class Codes: A61B 2017/320095 with sealing or cauterizing means

Abstract

An oscillating circuit for determining a resonant frequency of an electro-mechanical oscillating device and for driving the electro-mechanical oscillating device at the determined resonant frequency includes a driving circuit and a start-up, impetus injection circuit. The driving circuit is configured to receive one or more reference signals and further configured to provide a driving signal related to the reference signals to the electro-mechanical oscillating device. The start-up, impetus injection circuit is operably coupled to the electro-mechanical oscillating device and configured to selectively provide a start-up excitation signal to the electro-mechanical oscillation device. The start-up, impetus injection circuit is activated upon start-up of the oscillating circuit to drive the electro-mechanical oscillation device and the driving circuit determines a resonant frequency by measuring a parameter related to the resonant frequency of the electro-mechanical oscillating device.

Claims

1. An oscillating circuit for determining a resonant frequency of an electro-mechanical oscillating device and for driving the electro-mechanical oscillating device at the determined resonant frequency, the oscillating circuit comprising:

a driving circuit configured to receive at least one reference signal and further configured to provide a driving signal related to the at least one reference signal to the electro-mechanical oscillating device;

a start up excitation signal generating circuit operably coupled to the electro-mechanical oscillating device, wherein the start up excitation signal generating circuit is configured to selectively provide a start-up excitation signal to the driving circuit, and wherein the start up excitation signal generating circuit is activated upon start-up of the oscillating circuit to drive the electro-mechanical oscillation device, the start-up excitation signal generating circuit including;

a pseudo-random noise generator configured to generate the start-up excitation signal from a digital excitation sequence predetermined to be within the bandwidth of resonance of the electro-mechanical oscillating device; and

a start-up switch configured to selectively couple the start-up excitation signal to the driving circuit,

wherein the driving circuit determines a resonant frequency by measuring a parameter related to the resonant frequency of the electro-mechanical oscillating device.

2. The oscillating circuit of claim 1, wherein the start-up excitation signal is coupled to the driving circuit for a predetermined period of time.

3. The oscillating circuit of claim 2, wherein the predetermined period of time is determined by one of a controller and a user input.

4. The oscillating circuit of claim 1, wherein the start-up excitation signal is coupled to the driving circuit upon start-up when the resonance frequency of the electro-mechanical oscillating device is unknown.

5. The oscillating circuit of claim 1, wherein the start-up switch selectively couples the start-up excitation signal to the driving circuit when the resonance frequency of the electro-mechanical oscillating device has changed.

6. The oscillating circuit of claim 1, wherein the start-up switch selectively couples the start-up excitation signal to the driving circuit when a portion of the electro-mechanical oscillating device has changed.

7. The oscillating circuit of claim 1, wherein the start-up switch selectively couples the start-up excitation signal to the driving circuit when a portion of the electro-mechanical oscillating device is modified.

8. A method for starting an electro-mechanical oscillating device, the electro-mechanical oscillating device having a varying resonate frequency, the method comprising:

generating a start-up excitation signal from a pseudo-random noise generator with a digital excitation sequence predetermined to be within a bandwidth of resonance of the electro-mechanical oscillating device;

driving the electro-mechanical oscillating device with the start-up excitation signal;

measuring at least one parameter related to a resonant frequency of the electro-mechanical oscillating device;

determining a resonant frequency of the electro-mechanical oscillating device; and

driving the electro-mechanical oscillating device at the determined resonant frequency.

9. The method of claim 8, wherein the at least one parameter is selected from the group consisting of current, voltage and mechanical position.

10. The method of claim 9, further including:

selectively coupling the start-up excitation signal to the electro-mechanical oscillator for a predetermined period of time, wherein the predetermined period of time is determined by one of a controller or a user input.

11. The method of claim 8, further including enabling the pseudo-random noise generator when the resonance frequency of the electro-mechanical oscillating device has changed.

12. The method of claim 8, further including enabling the pseudo-random noise generator when a portion of the electro-mechanical oscillating device has changed.

13. The method of claim 8, further including enabling the pseudo-random noise generator when a portion of the electro-mechanical oscillating device is modified.

14. A method for starting an electro-mechanical oscillating device, the electro-mechanical oscillating device having a varying resonant frequency, the method comprising:

generating a time-frequency varying start-up excitation signal from a pseudo-random noise generator configured to generate a time-frequency varying start-up excitation signal from a digital excitation sequence predetermined to be within the bandwidth of resonance of the electro-mechanical oscillating device by activating a start-up switch coupling the pseudo-random noise generator to the electro-mechanical oscillating device;

applying the time-frequency varying start-up excitation signal to the electro-mechanical oscillating device;

driving the electro-mechanical oscillating device;

measuring at least one parameter related to a resonant frequency of the electro-mechanical oscillating device while driving the electro-mechanical oscillating device with the time-frequency varying start-up excitation signal;

determining the resonant frequency of the electro-mechanical oscillating device; and

driving the electro-mechanical oscillating device at the determined resonant frequency.

15. The method of claim 14, wherein the at least one parameter is selected from the group consisting of current, voltage and mechanical position.

16. The oscillating circuit of claim 14, wherein applying the time-frequency varying start-up excitation signal to the electro-mechanical oscillating device is performed upon start-up when a portion of the electro-mechanical oscillating device has changed.

17. The oscillating circuit of claim 14, wherein applying the time-frequency varying start-up excitation signal to the electro-mechanical oscillating device is performed upon start-up when the resonance frequency of the electro-mechanical oscillating device is unknown.

18. The oscillating circuit of claim 14, wherein applying the time-frequency varying start-up excitation signal to the electro-mechanical oscillating device is performed upon start-up when the electro-mechanical oscillating device is modified.