Microcomputer-based nerve and muscle stimulator

• US 4,926,865 A
• Filed: 01/17/1989
• Issued: 05/22/1990
• Est. Priority Date: 10/01/1987
• Status: Expired due to Fees

• Current Assignee: Paul S. Oman
• Original Assignee: Paul S. Oman
• Inventors: Oman, Paul S.
• Primary Examiner(s): Jaworski, Francis
• Assistant Examiner(s): Manuel, George
• Application Number:
  US07/298,782
• Time in Patent Office: 490 Days
• Field of Search: 128/421, 128/422, 128/783
• US Class Current: 607/59
• CPC Class Codes: A61N 1/025 Digital circuitry features of electrotherapy devices, e.g. memory, clocks, processors
• CPC Class Codes: A61N 1/36003 of motor muscles, e.g. for walking assistance
• CPC Class Codes: A61N 1/36034 specified by the stimulation parameters

Abstract

A transcutaneous nerve stimulation device is provided with mircocomputer-based control of pulse duration, pulse repetition rate, stimulation duty cycle and modulation of pulse parameters. The microcomputer 2 monitors battery 15 voltage and patient manipulated controls 14 that select pulse current amplitude and also provides signals used for display on a liquid crystal display 10 of all relevant stimulation parameters and warning annuciators. The microcomputer 2 is sensitive to input controls for calculation of all stimulation parameters, other than current amplitude, only when a program control switch 18 is active. When the program control switch 18 becomes inactive, the selected control information is stored in non-volatile memory 4, thereby providing electronic isolation of programming controls. The preferred embodiment of the nerve stimulation device may be used either for pain relief or to facilitate muscle contractions, which has a variety of therapeutic applications.

Claims

1. An electrical stimulator for use by a human patient, comprising:

(a) means for generating a pulsed signal, said pulsed signal having parameters including an amplitude, a pulse width and a frequency, the parameters having values;

(b) means, cooperatively connected to said generating means, for controlling the parameters of said pulsed signal, said controlling means including;

(i) operator control means for adjusting the values of a first subset of the parameters of said pulsed signal, said first subset of the parameters including signal current amplitude;

(ii) first programming control means for establishing the values of a second subset of the parameters of said pulsed signal including signal modulation amplitude, on time, off time, rise time, signal modulation rate, type of signal modulation, signal pulse width, and signal pulse frequency;

(iii) second programming control means for selectively initiating and terminating access to said first programming control means, wherein upon termination of access to said first programming control means, the values of said second subset of the parameters may not be varied until access to said first programming control means is initiated; and

(c) a microprocessor, operatively connected to said first and second programming control means, wherein said first and second programming control means supplies input data to said microprocessor, said microprocessor operatively connected to a non-volatile electrically erasable programmable read only memory to store parameters.

7. The electrical stimulator of claim 1, wherein said first programming control means comprise a plurality of potentiometers, whereby the adjustment of said second subset of the parameters is accomplished by means of said potentiometers, each of said potentiometers corresponding to a specific parameter of said pulsed signal, and wherein said potentiometers establish signals which are acted on by said microprocessor, wherein the values of said second subset of the parameters are variable over a range to permit use of the electrical stimulator as either a transcutaneous electrical nerve stimulator or as a muscle stimulator.

8. The electrical stimulator of claim 7, wherein the values of said second subset of the parameters are limited by maximum values, whereby said pulsed signal will be safe to the patient utilizing the stimulator regardless of adjustment to said operator control means.

9. The electrical stimulator of claim 1, wherein said first programming control means comprise a plurality of contact switches, whereby the adjustment of said second subset of the parameters is accomplished by means of said switches, each of said switches corresponding to a specific parameter of said pulsed signal.

10. The electrical stimulator of claim 9, wherein said switches establish signals which are acted on by said microprocessor, whereby the values of said second subset of the parameters are variable over a range to permit use of the electrical stimulator as either a transcutaneous electrical nerve stimulator or as a muscle stimulator.

11. The electrical stimulator of claim 10, wherein the values of said second subset of the parameters are limited by maximum values, whereby said pulsed signal will be safe to the patient utilizing the stimulator regardless of adjustment to said operator control means.

2. An electrical stimulator for use by a human patient, comprising:

(a) first means for generating a pulsed signal, said pulsed signal having parameters including an amplitude, a pulse width and a frequency; and

(b) second means cooperatively connected to said first means for controlling the parameters of said pulsed signal, said second means including;

(i) operator control means for adjusting the values of a first set of the parameters of said pulsed signal generated by said first means, said first set of pulsed signal parameters includes signal current amplitude, and

(ii) programming control means for establishing the values of a second set of the parameters of said pulsed signal, whereby the values of the parameters of the pulsed signal generated by said first means is determined by the values of the first and second set of parameters, said second set of said pulsed signal parameters includes signal modulation amplitude, on time, off time, rise time, signal modulation rate, type of signal modulation, signal pulse width, and signal pulse frequency and wherein said second means for controlling said pulsed signal parameters is a microprocessor, said microprocessor having a non-volatile electrically erasable programmable read only memory to store parameter sets, and wherein the adjustment of said pulsed signal parameters within said second set is accomplished by means of a plurality of potentiometers, each potentiometer corresponding to a specific pulsed signal parameter, said potentiometers thereby serving as said programming control means.

3. The electrical stimulator of claim 2 wherein the parameter values within said second set of pulsed signal parameters may vary over a range to permit use of the electrical stimulator as either a transcutaneous electrical nerve stimulator or as a muscle stimulator.

4. The electrical stimulator of claim 3 wherein the parameter values within said first set of pulsed signal parameters are limited by maximum values, whereby the stimulator will be safe to the patient utilizing the stimulator regardless of the adjustment to said operator control means.

5. The electrical stimulator of claim 4 wherein said pulsed signal parameter values within said first set of pulsed signal parameters may be selectively adjusted by the patient by said operator control means, said first set of pulsed signal parameters determining elementary parameters and second set of parameters determining less elementary parameters.

6. An electrical stimulator for use by a human patient, comprising:

(a) means for generating a pulsed signal, said pulsed signal having parameters including an amplitude, a pulse width and a frequency, the parameters having values;

(b) means, cooperatively connected to said generating means, for controlling the parameters of said pulsed signal, said controlling means including;

(i) operator control means for adjusting the values of a first subset of the parameters of said pulsed signal, said first subset of the parameters including signal current amplitude;

(ii) first programming control means for establishing the values of a second subset of the parameters of said pulsed signal including signal modulation amplitude, on time, off time, rise time, signal modulation rate, type of signal modulation, signal pulse width, and signal pulse frequency.

wherein said first programming control means comprise a plurality of potentiometers, whereby the adjustment of said second subset of the parameters is accomplished by means of said potentiometers, each of said potentiometers corresponding to a specific parameter of said pulsed signal; and

(iii) second programming control means for selectively initiating and terminating access to said first programming control means, wherein upon termination of access to said first programming control means, the values of said second subset of the parameters may not be varied until access to said first programming control means is initiated.

12. An electrical stimulator for use by a human patient, comprising:

(a) means for generating a pulsed signal, said pulsed signal having parameters including an amplitude, a pulse width and a frequency, the parameters having values;

(b) means, cooperatively connected to said generating means, for controlling the parameters of said pulsed signal, said controlling means including;

(i) operator control means for adjusting the values of a first subset of the parameters of said pulsed signal, said first subset of the parameters including signal current amplitude;

(ii) first programming control means for establishing the values of a second subset of the parameters of said pulsed signal including signal modulation amplitude, on time, off time, rise time, signal modulation rate, type of signal modulation, signal pulse width, and signal pulse frequency;

(iii) second programming control means for selectively initiating and terminating access to said first programming control means, wherein upon termination of access to said first programming control means, the values of said second subset of the parameters are stored in a non-volatile memory, whereby inadvertent patient modification of the values of said second subset of parameters is prevented; and

(c) a microprocessor, operatively connected to said first and second programming control means and said operator control means, wherein said first and second programming control means and said operator control means supplies input data to said microprocessor, said microprocessor including an internal non-volatile electrically erasable programmable read only memory to store said second subset of parameters.