CIRCUIT FOR RADIOFREQUENCY DEVICES APPLICABLE TO LIVING TISSUES AND DEVICE CONTAINING SAME

• US 20100198213A1
• Filed: 05/26/2008
• Published: 08/05/2010
• Est. Priority Date: 06/20/2007
• Status: Active Grant

• Current Assignee: INDIBA, S.A.
• Original Assignee: INDIBA, S.A.
• Inventors: Lario García, Javier, Buisan Escartin, Jorge, Calbet Benach, José
• Granted Patent: US 8,465,483 B2
• Time in Patent Office: Days
• US Class Current: 606/33
• CPC Class Codes: A61B 18/1206 Generators therefor
• CPC Class Codes: A61B 18/1402 Probes for open surgery
• CPC Class Codes: A61B 2018/128 generating two or more frequencies
• CPC Class Codes: A61B 2018/1293 having means to prevent interference
• CPC Class Codes: H03H 7/0115 comprising only inductors and capacitors H03H7/075, H03H7/09, H03H7/12, H03H7/13 take precedence
• CPC Class Codes: H03H 7/175 Series LC in series path H03H7/1783 takes precedence
• CPC Class Codes: H03H 7/1775 Parallel LC in shunt or branch path H03H7/1791 takes precedence

Abstract

The supply circuit for the electrodes comprises a series resonant filter and a parallel resonant filter, synthonised to admit the fundamental signal of the input signal and simultaneously and exponentially attenuate the remaining harmonics by increasing the frequency thereof, in such a way that the input signal with harmonics only passes the fundamental signal without attenuation to the output, while the harmonics causing interferences are increasingly attenuated as their frequency is raised.

Claims

1. A circuit for supplying output electrodes of a radiofrequency device applicable to living tissues, said circuit comprising:

a resonant serial filter having an inductor L_S1 and a capacitor C_S1;

resonant parallel filter having an inductor L_P and a capacitor C_P; and

a transformer separating the resonant serial filter from the resonant parallel filter, said transformer having a turn ratio of 1;

N, where N is a real number,

wherein the resonant serial filter and the resonant parallel filter allow a fundamental signal of an input signal, which includes harmonics, to simultaneously pass through and exponentially attenuate the harmonics as the frequency of said harmonics increases, and

wherein the output frequency of said circuit varies based on the impedance of an electrode-plus-patient unit such that the circuit matches the impedances of an output circuit to the impedance of the electrode-plus-patient unit.

2. The circuit of claim 1, wherein the inductor L_P of the resonant parallel filter is the parasitic inductance of a secondary coil of the transformer.

3. The circuit of claim 1, wherein inductor L_P of the resonant parallel filter L_P is an independent inductor.

4. The circuit of claim 1 including anti-stimulus capacitors C_S2—

_CAP, C<sub>S2—

RES</sub> at each output electrode, each of said anti-stimulus capacitors C<sub>S2—

CAP</sub>, C<sub>S2—

RES</sub> having a corresponding inductor L<sub>S2—

CAP</sub>, L<sub>S2—

RES</sub> connected in series, the inductors L<sub>S2—

CAP</sub>, L<sub>S2—

RES</sub> having values that resonate at the fundamental frequency of the input signal.

5. The circuit of claim 1, wherein the inductor L_S1 and the capacitor C_S1 of the resonant serial filter have a lower impedance to the fundamental frequency of the input signal and a higher impedance to the harmonics of the input signal.

6. The circuit of claim 5, wherein the inductor L_S1 and the capacitor C_S1 of the resonant serial filter have low impedance to the fundamental frequency of the input signal and high impedance to the harmonics of the input signal.

7. The circuit of claim 1, wherein the inductor L_P and the capacitor C_P of the resonant parallel filter have a higher impedance to the fundamental frequency of the input signal and a lower impedance to the harmonics of the input signal.

8. The circuit of claim 7, wherein the inductor L_P and the capacitor C_P of the resonant parallel filter have high impedance to the fundamental frequency of the input signal and low impedance to the harmonics of the input signal.

9. The circuit of claim 1, wherein the radiofrequency device is a diathermy device.

10. The circuit of claim 1, wherein the radiofrequency device is an electroscalpel device.