FR2507088A1 - PULSE GENERATOR FOR ANALGESIC BANDAGE - Google Patents

Abstract

BANDAGE FOR TRANSCUTANEOUS NERVOUS ELECTRIC STIMULATION CONSISTING OF AN AUTONOMOUS ASSEMBLY INCLUDING A SUPPLY SOURCE, A PULSE GENERATOR 28, A BUFFER CIRCUIT AND PULSE CONFORMER 32, A PULSE OUTPUT CIRCUIT 34, A REGULATING MEANS 'AMPLITUDE 40 AND AN AUDIO TRANSDUCER 42 RESPONDING TO VARIATIONS IN PULSE AMPLITUDE. A POSITIVE REACTION CIRCUIT 36 IS MOUNTED AT THE TERMINALS OF THE PULSE OUTPUT CIRCUIT 34 FOR PROVIDING REPETITIVE TRAINS OF MULTIPLE PULSES 38. THE TRANSDUCER PROVIDES A SOUND LEVEL REPRESENTATIVE OF THE INSTANT REPEAT TRAIN MEANS FOR ADJUSTING PULSE AMPLITUDE 40.

Description

2 So_ 7 '0 g

  The present invention relates to devices

  tifs, usually called analgesic bandages, which are applied to an injured part of the body for the purpose of calming or masking the pain caused by an injury, and it relates in particular to analgesic bandages

  of this kind which are autonomous, that is to say which do not

  no cables or wires connecting to organs

  outdoor sources such as power sources, sources

  impulse signals or other signal generators

general, etc.

  As an illustration of the state of the art

  that, one can refer to the patents of the United States n O

4,014,347 and 4,105,017.

  There are currently devices

  called analgesic bandages which are self-contained units

  my own to be applied directly to an injured part of the body to treat or modify pain. Such devices modify pain by transmitting weak electrical signals through the skin to the underlying nerves in accordance with a technique called "transcutaneous nerve electrostimulation", usually designated by the acronym TENS It has been discovered that electric currents inhibit or mask a

  one way or another the transmission of dou-

  their by the immediately adjacent peripheral nerves

to the injured body part.

  In a known autonomous pain reliever bandage

  both using transcutaneous nerve electro-stimulation

  born, the bandage has a flexible case containing a power source and a pulse generator which drives a pulse output circuit to the effect

  to provide repetitive electrical impulses to

  rant low and amplitude and repetition rate fixed at respective flat electrodes provided on the bottom of the housing A flexible segmented element containing an electrolyte gel is placed between the electrodes provided on

  the bottom of the bolt and the skin of the patient to allow

  be electric impulses to go by conduction

  of one of the electrodes and of an electrolyte segment as-

  company, to cross the patient's skin and return to another segment of electrolyte and to the second electrode

  associated These devices are small units, porta-

  relatively inexpensive compared to other transcutaneous nerve electro-stimulation units in existence today, which require fixation

  wires, cables, or electrodes in pre-

  cis of the body and which require an adjustment of the rhythm of im-

  impulses, the amplitude of the impulses and the frequency

  this pulses on the pulse signal generator-

  exterior nels On the other hand, the analgesic bandages,

  smaller and less expensive, have a power supply

  tion and an internal and autonomous pulse generator.

  Such self-contained units can be used by who-

  conch without requiring any special training since the rhythm, amplitude and frequency of the pulses

  are normally fixed, and therefore not adjustable.

  Generally speaking, such analgesic devices

  provide repetitive impulses at a rate of

  about 100 pulses per second, with a width of

  pulses of approximately 100 microseconds and an amplitude

  pulses of approximately 20 volts peak to peak for a ban-

  dage of small dimensions, this amplitude going up to

  at 80 volts peak to peak for greater bandage.

  In certain treatment situations, it is desirable to apply more energy during the pulsed part of the treatment signal. On large transcutaneous nerve electro-stimulation units, this can be easily done by widening the pulses,

  increased pulse amplitude, or increased

  power supply.

  Reference may be made, for example, to U.S. Patent No. 4,105,017 cited above, which describes a two-mode unit in which a second

  mode gives rise to the delivery of a repetitive train of im-

  multiple pulses o the width of the train is significantly greater than the width of the individual pulses delivered in the first mode fabrics Obtaining a train of multiple pulses, as opposed to a single pulse, is achieved by implementing switching circuits in which two oscillators are used, one of which

  is at low frequency, and the other at higher frequency.

  We now wish to obtain an increase

  of energy per treatment pulse in the available

  transcutaneous nerve electro-stimulation

  small and portable of the type forming an analgesic bandage

  tonome In this kind of application, the solution consists

  so much to use a switching of two oscillators is not viable, since it does not provide energy

  increased at the pulse train, and on the other hand reduces the energy

  effective, that it increases the cost price by

  the device and that it requires a larger footprint.

  Thus, it is specifically desired to achieve

  be an economic circuit that can apply trains

  repetitive multiple pulses at the same repetition rate

  tition that the analgesic bandage devices of the

  PRIOR ART If this result was achieved, this

  cooked could provide the desired increase in energy

  delivered by train without the need to modify or source

  neither the pulse width nor the ampli

  study of the impulses, nor the rhythm of repetition fluently

  adopted in existing analgesic bandages.

  To this end, the present invention provides an autonomous portable bandage adapted to be applied against a painful part of a patient's body, comprising a pulse generator circuit provided with a pulse output control stage capable of giving birth

  in the patient's body at repeated electrical impulses

  low-current titives intended to calm the pain emanating from the painful part, and in which is provided a reinjection means coupled to the control stage of

2507 OC 8

  pulse output to provide repeat trains

  multiple impulses to increase the

  amount of energy available to be applied to the pa-

  holds during impulses The self-contained bandage

  a power source, such as a battery or electric battery, and the repetitive electrical pulses are at a fixed repetition rate The reinjection means

  includes a positive feedback circuit such as a

  resistance cooker and capacitor connected in series connected

  across the pulse output control stage.

  The repetitive multiple pulse trains have a repetition rate which is the same as the fixed repetition rate.

  Amplitude variation means are covered

  connected to the output circuit to allow the patient to

  adjust the amplitude of repetitive trains of multiple pulses

  Many acoustic means are also coupled to

  amplitude variation means, so that there is

  delivery of an acoustic signal corresponding to the ampli

  Study of the repetitive train of multiple pulses in response

  at the adjustment position of the amplification variation means

study.

  The autonomous bandage perfected according to the pre-

  sente invention advantageously provides repeat trains

  desired pulses of multiple pulses in an entire unit

  completely autonomous to allow a patient to use this type of impulse treatment signal in the transcutaneous nerve electro-stimulation mode without being embarrassed by external electrical supply wires or by signal routing cables

  starting from the bandage In addition, the patient only needs

  take care to adjust the amplitude of the pulses to your liking,

  without special training being imposed on it to

  see setting the pulse width or the repetition rate

tition.

  The description and the attached figures, given

  by way of example, will make it clear how the invention can be made *

  Figure 1 is a perspective view shown

  feeling an autonomous bandage applied directly to a painful part of the body of a patient and putting in

  implements the basic provisions of the present invention.

  Figure 2 is a block diagram showing the electrical circuit with reinjection means provided

  in the analgesic bandage of Figure 1 according to the pre-

invention.

  Figure 5 is a detailed electrical diagram

  feedback means, amplifier adjustment means

  study and acoustic signaling forming part of an analgesic bandage according to the basic provisions of the present invention for providing repetitive trains

multiple pulses.

  FIG. 4 is a schematic plot represented

  both the repetitive multiple pulse trains obtained

  in accordance with the basic devices of this in-

vention O

  In the figures, the numerical references sem-

  blables denote similar building blocks.

  Figure 1 shows an analgesic bandage

  tone 10 suitable for 8 be applied to an injured part of the

  body of a patient, such as his forearm 12 The banda-

  analgesic age 10 has a flexible boot that presents

  te a compartment 14 containing a portable power source, such as a battery or electric battery, a

  compartment 16 containing a pulse generator circuit

  sions powered by the battery, an on / off switch

  stop 18 and a dial 20 intended to adjust to the set value

  the amplitude of the impulses of the impulse signals

  exits compartments 14 and 16 are one

  holding with a base 22 which contains electrodes

  your respective ones provided on the bottom surface thereof

  which is located on the side of the patient's body As

  naked per se, a flexible electrolyte pad containing

  segmented portions of gel is sandwiched between the elect

  base and body of the patient

2507088-

  then held in place by strips of suitable tape

  prayers 24 placed over the base portion 22.

  Figure 2 shows in block diagram form an electrical circuit 26 which is enclosed in compartment 16 and provides repetitive trains

  multiple pulses in the self-contained bandage 10

  in accordance with the basic provisions of this invention

  A pulse generator 28 provides pulses.

  repetitive elementary ions 30 which are then trans-

  bet, by means of a circuit forming means 32

  buffer and pulse shaper, to an output circuit

  pulse tie 34 A positive feedback circuit 36 is mounted across the pulse output circuit

  34, from which follows repetitive trains of im-

  multiple pulses 38 whose amplitude is adjusted by means of amplitude adjustment 40 for transmitting the repetitive trains via terminals A and B to the respective electrodes located below the base

  22 A transducer 42 reacts to variations in the ampli

  study by providing a corresponding sound level which

  is representative of the instantaneous amplitude of the train

  petitive 58, as adjusted by the am-

pulse width 40.

  FIG. 3 represents, in the form of an electrical diagram, the electrical circuit corresponding to the functional diagram of FIG. 2, except for the input trigger stage 44 represented by FIG. 3 As an alternative to the use of the on switch / stop 18 to trigger the pulse generator 28, a trigger circuit 44 is used, one input of which is

  connected by a terminal C to a respective additional electrode

  provided on the bottom of the base 22 In the cir-

  cooked in Figure 3, when placing the bandage

  on the skin, the trigger circuit 44 is located

  activated by actuation of the on / off switch

  18 placed in series with the power supply to

  click on circuit 44 and make it begin delivery

pulses 30.

  In Figure 3, when the trip circuit

  44 is activated, a transistor 46 is brought into contact

  maximum duction so as to place the electric supply battery at the terminals of a resistance circuit 48 and

  capacitor 50 in series, which plays the r 8 le of a circuit

  cooked at RO time constant to set the frequency

  pulse signal repetition oscillation or rhythm

  final resistor 48 and capacitor 50, as well

  association with the unijunction transistor 52, provide a pulse signal 30 whose repetition rate

  is less than 150 pulses per second, with a lar-

  pulse encoder between 50 and 400 microseconds and a pulse amplitude between a minimum

  peak-to-peak of O volt and maximum peak-to-peak of

about 60 to 80 volts.

  A PNP buffer and conforming circuit comprising

  both a transistor 54 optimizes the pulse 50 as to its width and its amplitude, and it delivers the corresponding output pulses through a resistor 56 and an output circuit comprising an NPN transistor 58 and

  an output transformer 60 The output transformer

  tie 60 has a primary winding 62 and a winding

  secondary median setting 64 In the form of

  reading of the invention represented by FIG. 3, the

  positive feedback circuit 36 includes a feedback circuit

  sistor 66 and capacitor 68 connected in series which connects the center tap terminal 70 to the input terminal 72 Aux

  output transformer secondary terminals is mon-

  t a potentiometer 74, one of the terminals of which is connected to terminal A. It has been found that by adjusting the potentiometer 66, it is possible to obtain, between the output terminals A and B, pulse trains containing 1, 2 or 3 pulses A

  as an example, figure 4 represents a repeating train

  tif of three pulses at the same repetition rate as the rate determined by a train of pulses containing the

  pulse signal 30 established by the pulse generator

  sions 28 As shown in Figure 4, each train 78 contains a combination of pulses 80, 82, 84 separate

by a level of rest 86.

  Pulse amplitude output is set

  by varying the position of the cursor 76 of the potentiometer

  meter 74 An acoustic piezoelectric crystal indicator

  that 88 connected to the terminals of the variable output provides a

  acoustic indication of the instantaneous amplitude of the im-

  output pulses Thus, when adjusting

  amplitude of the output pulses, the output level

  of the piezoelectric indicator 88 varies, the varia-

  output amplitude level of the indicator

  thus being stronger for an output amplitude of im-

  stronger impulses and being at an amplitude level of

  proportionally lower output for the amplitudes of

  weaker impulses So the user has a

  direct correlation between the acoustic intensity and the am-

  pulse output fullness A fault capacitor

  9 o coupling is mounted across the power source

electric tion.

  In an embodiment of the invention constructed in accordance with the provisions of Figures 3 and 4, there was obtained a repetitive train of multiple pulses having a repetition rate of about 70 Hz, a train width 78 of about 160 microseconds , and an adjustable train amplitude from approximately 0 volts to approximately 60

  at 80 volts peak-to-peak The components used to obtain

  hold such a pulse signal are as follows (in

  considering figure 3) Resistance 11: 50 kilohms; re-

  resistance 13: 200 kilohms; resistance 48: 68 kilohms; resistor 15: 100 ohms; resistor 17: 220 ohms; resistance 19: 5.6 kilohms; resistor 21: 47 ohms resistor 23: 1 kilohm; resistance 56: 10 kilohms; potentiometer 66: 50 ohms; potentiometer 74: 5 kilohms; capacitor 50: 0.1 / u F; capacitor 90: 10 / u F, electrolytic; capacitor 68: 0.1 / u F; transistor 46: MPS A 20; 52: 2 N 2646 unijunction transistor or

  2 N 4871; transistor 54: 2 N 3906; transistor 58: MPS A 14.

  The output transformer 60 was formed by a transformer

  low frequency trainer presenting at the frequencies

  ticks a primary winding impedance of 8 ohms and a secondary winding impedance at acoustic frequencies of 1 kilohm, with a primary resistance

  direct current of 0.95 ohm and a resistance of

  condaire in direct current of 6,5 ohms The piezoelectric horn 88 was a component of the trade of the type 7 BB-20-6 A O manufactured by the firm Murata,

  It should be understood that the description

  detailed above has been given only as an example

  purely illustrative and that various modifications and

  laughs obvious to those skilled in the art can be made without departing from the framework of

  the invention as defined by the claims above

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Claims (8)

  1 stand-alone bandage suitable for application   be a painful part of a patient's body, said   bandage comprising a circuit (28) suitable for giving birth   using repetitive low current electrical pulses in the patient's body to relieve pain   from the painful part, characterized by a mo-   feedback yen (34, 36) coupled to said circuit (28, 32)   so as to provide repetitive trains of multiple pulses   multiple to be applied to the patient during say impulses.   2 autonomous bandage according to claim 1, characterized in that said reinjection means (34,36)   includes a positive feedback means (36).   3 autonomous bandage according to claim 2, characterized in that said positive reaction means (36) comprises a resistor (66) and a capacitor (68) mounted in series.   4 autonomous bandage according to claim 3,   characterized in that said resistor (66) mounted in se-   is variable to vary the rate of   positive reaction and the resulting number of multiple pulses   multiple within said repeating trains.   Autonomous bandage according to claim 1, characterized in that it comprises means (74) suitable for   varying the amplitude of said repetitive trains of im-   multiple pulses * 6 Autonomous bandage adapted to be applied to   an injured part of a patient's body, said bandage   taking a power source and a circuit means provided with a pulse generator and a pulse output circuit to give rise to repetitive electric pulses of low current and amplitude and rhythm of fixed repetition in the body of the   patient in order to calm the pain from said lesion   sion, and being characterized by feedback means (34,36) coupled to said circuit means for the purpose of providing 1 l of repetitive trains of multiple pulses, said   trains being at the same 8th repetition rate as said rhythm-   fixed repeat me; amplitude varying means (40) coupled to the output of said circuit means for varying the amplitude of said repeating trains   multiple pulses; and an acoustic means (42) covered   plé to said amplitude variation means to provide an acoustic signal corresponding to the amplitude of said repetitive train of multiple pulses in response   said means of amplitude variation.   7 autonomous bandage according to claim 6, characterized in that said feedback means (34,36) comprises a positive feedback circuit (36) mounted at   terminals of said pulse output circuit (34).   8 autonomous bandage according to claim 7, characterized in that said positive feedback circuit   includes a resistor (66) and a capacitor (68) tees in series.   9 Autonomous bandage according to claim 6, characterized in that said pulse output circuit comprises a transformer (60 ') having a secondary winding (64) of output with median tap, means (66,68) connecting said means of reinjection to said center grip   (70) and at the input (72) of said pulse output circuit sions.   Autonomous bandage according to claim 9, characterized in that the amplitude variation means comprises an adjustable potentiometer (74) mounted at the terminals of said secondary winding of outputs 11 Autonomous bandage according to claim 10, characterized in that said acoustic means comprises   piezoelectric indicator member (88).   12 Autonomous bandage according to claim 6, characterized in that said reinjection means (34, 36) comprises only passive components,