Electrotherapy apparatus with superimposed AC fields

• US 5,476,481 A
• Filed: 06/20/1994
• Issued: 12/19/1995
• Est. Priority Date: 11/15/1991
• Status: Expired due to Term

• Current Assignee: Ralf Scherer, Robert Ley
• Original Assignee: Ralf Scherer, Robert Ley
• Inventors: Schondorf, Erhard
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US08/240,644
• Time in Patent Office: 547 Days
• Field of Search: 607/2, 607/67, 607/68, 607/69, 607/71
• US Class Current: 607/2
• CPC Class Codes: A61N 1/0452 Specially adapted for transcutaneous muscle stimulation [TMS]
• CPC Class Codes: A61N 1/0456 Specially adapted for transcutaneous electrical nerve stimulation [TENS]
• CPC Class Codes: A61N 1/32 alternating or intermittent currents applying electric fields by inductive or capacitive coupling A61N1/40; microwave apparatus A61N5/02
• CPC Class Codes: A61N 1/36034 specified by the stimulation parameters

Abstract

An electrotherapeutic field stimulator includes at least a pair of electrodes for applying the electricity to the body in the form of an electric field and a generator for providing the electricity to the electrodes in the form of at least two superimposed alternating current fields of different frequencies to provide the treatment waveform.

Claims

1. Electrotherapy apparatus for treating tissue, said apparatus comprising

electrodes between which tissue can be disposed for treatment,

means for producing a first alternating field between said electrodes, said first alternating field having a frequency between 0.1 Hz and 5 Hz;

and

means for superimposing a second alternating field with a frequency of 1 to 100 Hz on said first field.

2. Electrotherapy apparatus as in claim 1 further comprising means for superimposing a third alternating field on said second field so that said second field serves as an envelope of said third field, said third field having a higher frequency than said second field.

3. Electrotherapy apparatus as in claim 2 wherein said third alternating field has a frequency between 3000 and 4000 Hz.

4. Electrotherapy apparatus as in claim 2 wherein said means for superimposing a second field comprises means for superimposing voltages having two adjacent frequencies to produce a heterodyne curve which serves as said envelope.

5. Electrotherapy apparatus as in claim 4 wherein said adjacent frequencies have a difference of 10 Hz, whereby said second field has a frequency of 10 Hz.

6. Electrotherapy apparatus as in claim 5 wherein said adjacent frequencies are 4000 Hz and 3990 Hz.

7. Electrotherapy apparatus as in claim 4 wherein said means for superimposing a second field comprises

a first oscillator which outputs a voltage having one of said adjacent frequencies,

a second oscillator which outputs a voltage having the other of said adjacent frequencies, and

a first mixer which superposes the output voltages of respective said first and second oscillators.

8. Electrotherapy apparatus as in claim 7 further comprising a second mixer which superimposes said second field on said first field.

9. Electrotherapy apparatus as in claim 8 further comprising an amplifier between said first mixer and said second mixer.

10. Electrotherapy apparatus as in claim 8 further comprising an adjustable amplifier between said second mixer and said electrodes.

11. Electrotherapy apparatus as in claim 4 wherein said superimposed voltages have the same amplitude.

12. Electrotherapy apparatus as in claim 4 wherein said first alternating field has an amplitude which is approximately twice the height of said envelope.

13. Electrotherapy apparatus as in claim 1 wherein said first alternating field is a square wave alternating field.

14. Electrotherapy apparatus as in claim 1 wherein said first alternating field is a sinusoidal alternating field.

18. Electrotherapy apparatus as in claim 1 wherein said means for producing said electric field is an AC power supply having a voltage U_M and said means for reversing the polarity of said electrodes is an AC power supply having a voltage U_G, said apparatus comprising means for superimposing said voltage U_G on said voltage U_M.

15. Electrotherapy apparatus for treating tissue, said apparatus comprising

electrodes between which tissue can be disposed for treatment,

means for producing an electric field having a carrier frequency f_t between said electrodes, said electric field having an amplitude,

means for modulating said amplitude according to a modulation frequency f_m of 1 to 100 Hz, and

means for reversing the polarity of said electrodes according to a fundamental frequency f_g of 0.1 to 5 Hz.

16. Electrotherapy apparatus as in claim 15 wherein said carrier frequency f_t is 3000 to 4000 Hz.

17. Electrotherapy apparatus as in claim 15 wherein said fundamental frequency f_g is 0.1 to 1 Hz.