U.S. patent number 3,718,132 [Application Number 05/022,809] was granted by the patent office on 1973-02-27 for electrotherapy machine.
This patent grant is currently assigned to Neuro Systems Inc.. Invention is credited to Roger Boy de la Tour, William J. Holt.
United States Patent |
3,718,132 |
Holt , et al. |
February 27, 1973 |
ELECTROTHERAPY MACHINE
Abstract
A machine for inducing sleep and other therapy effects by means
of repetitive electrical pulses wherein potential danger to the
treated subject is avoided by the generation of trains of rapid
alternately positive and negative pulses whose vectorial sum is
equal to zero, thus avoiding the application of net direct
currents. Trains of pulses are applied to the subject through a
transformer to avoid shock hazard. A timer attenuator allows
gradual rise in current over a fixed time period to a fixed level,
maintenance of the fixed current level for a variable time period
which may be set, and gradual decline in current over a fixed time
period.
Inventors: |
Holt; William J. (Garland,
TX), Boy de la Tour; Roger (Los Angeles, CA) |
Assignee: |
Neuro Systems Inc. (Garland,
TX)
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Family
ID: |
21811546 |
Appl.
No.: |
05/022,809 |
Filed: |
March 26, 1970 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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629232 |
Apr 7, 1967 |
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Current U.S.
Class: |
600/26;
607/63 |
Current CPC
Class: |
A61N
1/3603 (20170801); A61N 1/36014 (20130101); A61N
1/36034 (20170801) |
Current International
Class: |
A61N
1/32 (20060101); A61N 1/34 (20060101); A61N
1/36 (20060101); A61n 001/00 () |
Field of
Search: |
;128/1C,419-423 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
Radio-Electronics, Feb. 1965, PP. 40-42. .
Amer. Journ. of Med. Electronics, Jan.-Mar., 1965, PP. 39-41. .
Electronics, May 24, 1963, PP. 20-21. .
Electronics World, Sept., 1963, PP. 27-29..
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Primary Examiner: Howell; Kyle L.
Parent Case Text
This application is a continuation-in-part of our prior
application, Ser. No. 629,232 filed April 7, 1967, now abandoned.
Claims
What I claim as my invention and desire to secure by Letters Patent
of the United States is:
1. An electrotherapy device comprising: electrode means adapted to
be attached to a subject; first circuit means operating to produce
a train of electric pulses; second circuit means connected to and
cooperating with said first circuit means for producing a train of
periodic bursts of alternating current, each of said bursts having
a vectorial sum equal to zero, whereby to avoid impressing net
direct current on a treated subject, said second circuit means
connected in electrical communication with said electrode means and
adapted to deliver said bursts of alternating current to said
subject whereby to provide electrotherapeutic treatment; a direct
current power source, said second circuit means comprising gate
means connected to said power source and to said first circuit
means, said gate means being operated by electric pulses from said
first circuit means and operating to pass pulses of power from said
source, said second circuit means further comprising oscillator
means connected to said gate means for receiving said pulses of
direct current power and operating to produce said train of
periodic bursts of alternating current.
2. An electrotherapy device according to claim 1 which further
comprises power limiting means connected to said oscillator means
for restricting the power gain between pre-selected limits.
3. An electrotherapy device comprising: a power source; a pulse
generator receiving energy from the power source and producing
current pulse trains whose vectorial sum is equal to zero whereby
to avoid impressing net direct current on a treated subject; and
electrode means adapted to apply the current pulse trains to a
subject, said pulse generator including a relaxation oscillator
connected to the source of power, means connected to the relaxation
oscillator and to the power source, said means being adjustable to
generate a pulse of a given duration every time it receives a
signal from the relaxation oscillator, a gate which is open during
the duration of the pulse, said gate being connected to both the
positive and negative sides of the power source and to the pulse
generator, an oscillator which is connected to the gate and which
is connected to the negative side of the power source through the
gate when the gate is open, said oscillator being also connected to
the positive side of the power source and said oscillator having an
output which is a wave train of constant amplitude and a frequency
which is adjustable, the duration of the wave train being the
duration of the pulse produced by the pulse generating means, means
for amplifying the output of the oscillator, the oscillator and
amplification means together constituting the output circuit, and
means adapted to feed the amplified pulse train output of the
oscillator to the subject, said means adapted to feed the amplified
pulse train output of the oscillator to the subject being an
isolation transformer having its primary connected to the means for
amplifying the oscillator output and its secondary connected to
said electrode means, said electrotherapy device further including
manual attenuator means for adjusting the strength of the output
signal, said manual attenuator means being connected between the
secondary of the isolation transformer and the electrode means, and
timer attenuator means connected between the manual attenuator
means and the electrode means, the timer attenuator means enabling
the output current signal to be advanced over a set period of time
until the maximum current signal is reached, and maintaining the
maximum current signal for an adjustable period of time after which
the timer attenuator reduces the current signal to zero over a set
period of time.
4. An electrotherapy device according to claim 3 in which the
relaxation oscillator includes a unijunction transistor and a time
constant circuit including a variable resistor for a continuous
adjustment of the repetition rate, said variable resistor being
connected at one of the ends to the power source; a resistor, said
resistor being connected at one of its ends to the other end of the
variable resistor and at its other end to the emitter electrode of
the unijunction transistor; a selector switch having capacitors for
selection of the ranges of adjustment connected to the emitter
electrode of the unijunction transistor; a resistor to compensate
for ambient temperature variations, said resistor being connected
between the power source and the base 2 electrode of the
unijunction transistor; and a load resistor connected to the base 1
electrode of the unijunction transistor, the output signal of the
relaxation oscillator being developed across said load
resistor.
5. An electrotherapy device according to claim 3 in which the gate
is a double gate having the output signal of the relaxation
oscillator applied to one of its inputs, the output of the
particular gate connected to the output signal of the relaxation
oscillator being connected to the input of its twin gate through a
timing circuit, and the output of the double gate being connected
to a solid state switch which connects and disconnects the return
of the output circuit to and from the minus side of the power
source.
6. An electrotherapy device according to claim 5 in which the
output of the double gate is connected to the solid state switch
through a resistor which limits the maximum current that the switch
can carry thereby limiting the instantaneous output power to a safe
value.
7. An electrotherapy device according to claim 3 in which the
oscillator is a double gate having the input of each of its gates
connected by means of time constant circuits to the output of the
other gate, with the output of each gate being connected to a
limiting resistor, said limiting resistors limiting the input
current and thus the output power developed by the means for
amplifying the output of the oscillator for a given voltage, said
limiting resistors thus limiting the instantaneous output power to
a safe limit.
Description
This invention relates to a machine which induces sleep and other
therapy effects by the application of repetitive electrical pulses
to the head of a subject. The repetitive electrical pulses
generated are trains of rapid alternately positive and negative
pulses whose vectorial sum is equal to zero.
The inducement of sleep by means of repetitive electrical pulses
applied to the head of a subject is well known in the art. Many
instruments have been manufactured in the United States and abroad,
particularly in the Soviet Union, the United Kingdom, and Japan to
generate electrical pulses for application to the head. All of
these prior art generators, however, have one disadvantage in
common: they are potentially dangerous to the subject. The primary
danger, in addition to the shock hazard of those generators
utilizing vacuum tubes, is a result of the single polarity pulse
output to the subject provided by these prior art generators.
These single polarity pulses produce an electrolytic dissociation
in the living cells. No matter how minute the pulses, the
cumulative action of the numerous pulses can lead to an
irreversible damage to the brain.
This invention provides a pulse generator which does not apply any
single polarity component to the subject, thus avoiding any
electrolytic action and concomitant damage to the brain. Instead of
single polarity pulses, the sleep inducing machine of this
invention generates trains of rapid pulses, alternately positive
and negative, such pulses having a vectorial sum of zero.
The trains of pulses produced by the generator of this invention
are applied to the subject through a transformer, so that no
conductive path exists between the generator and the subject. This
isolation avoids any potential shock hazard.
An additional safety feature of the subject sleep inducing machine
is that the instantaneous output power to the subject is limited to
a value which is safe to humans. Any malfunction or fault in the
system results in reduced or no output power, rather than in a
maximum power output as is generally the case with prior art sleep
inducing machines.
An object of this invention is the provision of an electrotherapy
machine which generates trains of rapid pulses, alternately
positive and negative, such pulses having a vectorial sum equal to
zero.
Another object of this invention is to provide a machine which is
not dangerous to the subject.
An additional object of this invention is to provide a sleep
inducing machine which avoids any electrolytic action.
Still another object of this invention is to provide a sleep
inducing machine which avoids any potential shock hazard.
Yet another object of this invention is to provide a sleep inducing
machine whose instantaneous output power to the subject is limited
to a safe value.
A further object of this invention is to provide a sleep inducing
machine in combination with a timer attentuator which allows a
gradual rise in current over a fixed period of time to a fixed
level, maintenance of the fixed current level for a variable time
period which may be set, and a gradual decline in current over a
fixed time period.
Other objects and advantages of this invention will be particularly
set forth in the claims and will be apparent from the following
description, when taken in connection with the accompanying
drawings, in which:
FIG. 1 is a wave form diagram of the single polarity pulse output
of prior art devices.
FIG. 2 is a wave form diagram of the trains of rapid pulses,
alternately positive and negative produced by the generator of the
present invention.
Fig. 3 is a block diagram of the sleep inducing machine of the
invention.
FIG. 4 is a schematic circuit diagram of one embodiment of the
sleep inducing machine of the invention.
FIG. 5 is a front view of a recommended timer for the sleep
inducing machine.
FIG. 6 is a side view of the timer taken along the line 5--5 of
FIG. 5.
FIG. 7 is a graph showing the current time function achieved by the
timer of FIGS. 5 and 6.
FIG. 8 is a diagrammatic representation showing the arrangement of
the resistive elements of the potentiometers.
FIG. 9 is a diagrammatic representation showing the arrangement of
the potentiometers when the knob is set at 40 minutes.
FIG. 10 is a diagrammatic representation showing the wiper arms
moving in phase over a 40 minute setting.
FIG. 11 is a diagrammatic representation showing the wiper arms
moving in phase over a 60 minute setting.
The sleep inducing machine of the invention is comprised of the
elements as shown in FIG. 3 which operate as follows:
A direct current power source 1 provides energy to the transistor
circuits composing the pulse generator. The direct current power
source 1 as shown in FIGS. 3 and 4 has both a high and a low
positive side and a minus or zero potential side. The terms high
and low are relative indicating merely that the high side has a
higher output voltage than the low side. In one embodiment the high
positive side is 12 volts at 3 ma., the low positive side is 3
volts at 3 ma., and the minus side is at zero potential.
Applicant's invention may be constructed with a power source having
only one positive output voltage rather than the two positive
outputs or power supplies of the power source of the embodiment of
FIGS. 3 and 4, and applicant does not intend to limit the invention
to a power source having two positive outputs. The transistor
circuits are a relaxation oscillator 2 which provides a recurrent
signal to a monostable multivibrator 3. The monostable
multivibrator 3 can be adjusted to generate a pulse of a given
duration every time it receives a signal from the relaxation
oscillator 2. A gate 4 is open during the duration of the pulse.
While the gate is open it connects the power source 1 to the
oscillator 5 and the limited power amplifier 6. The output of the
oscillator 5 is a wave train of constant amplitude and of a
frequency which is adjustable between set limits. The duration of
the wave train is the duration of the pulse produced by the
multivibrator 3. The output of the oscillator 5 is connected
through limiting resistors to a push pull amplifier 6. The power
output of the push pull amplifier 6 is limited to a set number of
milliwatts instantaneous. Through an isolation transformer 7, the
pulse trains are fed to the two electrodes 8 and 9 which are
applied to the subject. The signal produced by prior art devices is
shown in FIG. 1. FIG. 2 shows the signal produced by the present
invention. The strength of the signal is adjustable through a
manual attenuator 10. The timer attenuator 11 provides an
adjustment whereby the signal current advances slowly over a fixed
period of time to a maximum level at which it is maintained for an
adjustable period of time after which the signal current is slowly
reduced to zero over a fixed period of time.
FIG. 4 is a schematic circuit diagram of one embodiment of the
sleep inducing machine of the invention within the scope of FIG. 3.
Integrated circuits (double NCR gates) are utilized for simplicity
and reliability.
The relaxation oscillator is composed of a unijunction transistor
20 together with a time constant circuit comprising a variable
resistor 21 for a continuous adjustment of the repetition rate, a
resistor 22 and three capacitors 23, 24, and 25 for selection of
the ranges of adjustment through a selector switch 26. A resistor
27 compensates for ambient temperature variations.
The output signal of the relaxation oscillator is developed across
the load resistor 28 and applied to one input of the double gate
29. The output of that particular gate to which the output signal
of the relaxation oscillator is applied is connected to the input
of its twin gate through a timing circuit including switch 30,
resistors 31 and 32 and capacitor 33. The output of the double gate
29 is connected to a solid state switch, NPN transistor 34, through
a limiting resistor 35.
The NPN transistor 34 connects or disconnects the return of the
output circuit to or from the minus side of the power source 1. The
maximum current that the NPN transistor 34 can carry is controlled
by the value of resistor 35. This is one of the two circuits which
limit the instantaneous output power of the sleep inducing machine
to a safe value.
The output circuit is composed of an oscillator and a push-pull
amplifier. The output circuit could be simplified by using an
oscillator connected directly to the subject; but with the omission
of the push-pull amplifier, the output could not be as accurately
controlled.
The oscillator is basically a double gate 36 in which each input is
connected by means of the time constant circuits to the output of
the other gate. The time constant circuits include resistors 37,
38, 40, and 41, switch 39, and capacitors 42 and 43.
The outputs of the two gates comprising double gate 36 are
connected by means of limiting resistors 44 and 45 to a push-pull
amplifier including NPN transistors 46 and 47 and transformer 48.
The primary of transformer 48 is shunted by capacitor 49. The
resistors 44 and 45 limit the input current and as a result limit
the output power developed by the transistors 46 and 47 for a given
voltage. The resistors 44 and 45 comprise the second built-in
security mechanism to limit the instantaneous power applied to the
subject to a safe limit.
The secondaries of the isolation transformer 48 feed three
different circuits as follows:
1. The output circuit to the electrodes 8 and 9 which are applied
to the subject. The output voltage is controlled by the switch 50
and the potentiometer 51.
2. The neon lamp 52 circuit, the neon lamp 52 being in series with
a limiting resistor 53 to provide a visual stimulus, and
3. The loudspeaker 54 circuit which provides an auditory
stimulus.
In compliance with a specific embodiment of the present invention,
the components heretofore described were selected to take the
values or designations set forth in Table I below.
TABLE I
Component Value or Designation transistor 20 2N2646 variable
resistor 21 500K ohm potentiometer resistor 22 100K ohms capacitor
23 2 mfd. capacitor 24 0.5 mfd. capacitor 25 0.1 mfd. resistor 27
270 ohms resistor 28 100 ohms gate 29 Fairchild .mu.1 914 resistor
31 2.7 K ohms resistor 32 2.7 K ohms capacitor 33 1 mfd. transistor
34 2N3565 resistor 35 3.9 K gate 36 Fairchild .mu.1 914 resistor 37
5.6 K ohms resistor 38 5.6 K ohms resistor 40 5.6 K ohms resistor
41 5.6 K ohms capacitor 42 0.05 mfd. capacitor 43 0.05 mfd.
resistor 44 22 K ohms resistor 45 22 K ohms transistor 46 2N3565
transistor 47 2N3565 transformer 48 core: 3/16"x3/16"Permalloy or
Hi-Nickel primary: 600 turns CT, No. 44 wire secondary: 900+900+900
turns, No. 44 wire; 50 turns. No. 44 wire. potentiometer 51 50 K
ohms neon lamp 52 NE-2 resistor 53 220 K ohms loudspeaker 54 3.2
ohms
In the specific embodiment outlined with respect to the values and
designations set forth in Table I, the power supply was selected to
be plus 12 volts on the high positive side and plus 3 volts on the
low positive side. In addition, the timer attenuator 11 was
selected to comprise a Type 0-100UA direct current ammeter
connected across the center of a diode bridge employing four 1N93
diodes, a filtering capacitor having a rating of 100 mfd. being
connected in parallel with the meter.
It has become apparent that the sleep inducing machine is most
effective when the current to the subject is advanced slowly over a
period of time. Through tests a period of approximately 5 minutes
has been found to be ideal. After attaining the maximum current
level, the signal is maintained at such level for a period of time
depending on how long sleep is desired to be induced. At the
expiration of the period during which the signal is maintained at
maximum current level, it has been found to be most effective to
reduce the current slowly to zero. Through tests it has been found
to be desirable to reduce the signal current from maximum to zero
over a period of 5 minutes. The timer shown in FIGS. 5 and 6
embodies one device for performing these functions. In addition the
timer of FIGS. 5 and 6 provides one means for varying the time of
maximum current flow from zero to the maximum time of 50
minutes.
Referring to FIG. 5, a front view of the timer is shown. FIG. 6
shows a side view. The timing element 60 is a conventional
escapement timer of the type commonly used in mechanical kitchen
timers. It can be wound by hand to a predetermined time whereupon
it will return to zero after that time period has elapsed. Fastened
to the winding shaft 61 of the timing element 60 are two
potentiometers 62 and 63. Potentiometer 62 is fastened to the base
member 64 by means of bracket 65 and nut 66. Wiper arm 67 moves
directly with the shaft 61 of the timing mechanism 60. Associated
with potentiometer 62 is toggle switch 68. This toggle switch 68
becomes operative when the time setting winding knob 69 is moved
off of the zero point at which time the toggle switch 68 turns on
the direct current power to the sleep inducing machine. Toggle
switch 68 serves the same function of switch 12 of FIGS. 3 and
4.
The second potentiometer 63 is mounted on the shaft 61 of the timer
mechanism 60, but is free to rotate about the shaft 61. The wiper
arm 71, however, is fastened rigidly to the shaft 61 and rotates in
phase with wiper arm 67. Fastened rigidly to potentiometer 63
housing 70 is a cylindrical member 72 which forms a bearing for
shaft 61 but which also has an appendage 73 which serves as an
indicator and a method for rotating the potentiometer 63 housing 70
relative to the shaft 61. Indicator 73 and potentiometer housing 70
are prevented from rotating freely about shaft 61 by a constant
spring pressure supplied by a spring 74. Spring 74 presses against
the case 75 of the instrument thus exerting a clutch force between
member 73 and case 75. Since indicator 73 and potentiometer 70 are
rigidly fastened together, these elements do not move relative to
each other.
The current time function is shown in FIG. 7 where it can be seen
that the current increases linearly from zero to maximum in 5
minute period and decreases linearly from maximum to zero in a 5
minute period. The time period of the maximum current is a variable
which can be set by the operator of the sleep inducing machine. The
elements of potentiometers 62 and 63 are special elements as shown
in FIG. 8. For 30.degree. of their rotation they are essentially
linear potentiometers. For the balance of their rotation they are
low resistances elements. The low resistance ends of the elements
are connected together electrically. In order to provide a variable
time period for the maximum current to flow it is necessary that
the relative positions of the high resistance elements 79 and 77 of
potentiometers 62 and 63 be changed. See FIGS. 9, 10 and 11. The
changing of the relative positions of the high resistance elements
79 and 77 can be done as follows:
Stop 76 which is fastened to potentiometer 70 as shown in FIG. 9 is
engaged by wiper arm 71 as shaft 61 is rotated to wind the timer
mechanism 60.
FIG. 9 shows the potentiometer arrangements when the knob 69 has
been set to 40 minutes. Under this condition the potentiometer
housing 70 has been rotated with wiper arm 71 engaging stop 76.
Indicator 73 will then be at 30 minutes which will be the time
period of maximum current. Indicator 73 remains in the position at
which it has been set as knob 69 rotates back to zero.
The potentiometer assembly serves as an attenuator for the current.
Thus at the start of the 40 minutes shown in FIG. 9, wiper arm 71
contacts the maximum resistance part of potentiometer 63, namely
high resistance element 77. Wiper arm 67 contacts the low
resistance part of potentiometer 62, namely low resistance element
78. See also FIG. 10. Thus, if the potentiometer high resistance
elements 77 and 79 are each assumed to have a resistance of 50,000
ohms, the maximum resistance of 50,000 ohms will occur between
terminals 80 and 81 at the start of the 40 minute cycle. As the
timer knob 69 rotates toward zero, wiper arm 71 rotates in a
counterclockwise direction along high resistance element 77 and in
a 5 minute period will contact low resistance element 82. Thus
after 5 minutes have expired wiper arms 71 and 67 are essentially
shorted together with a direct connection and there is no
attenuation to the current. This condition exists until the final 5
minute interval is reached at which time wiper arm 67 engages high
resistance element 79 and as the time progresses toward zero the
maximum resistance of high resistance element 79 is placed in the
circuit. Under these conditions the resistance between terminals 80
and 81 will be 50,000 ohms when wiper arm 67 reaches zero.
It can be seen in FIG. 11 that the same sequence described above
will take place if the timer mechanism 60 is wound to the full 60
minutes. Potentiometer housing 70 and indicator 73 would then be
rotated to 50 and would remain there until manually moved. The
operator can return indicator 73 to zero manually after each use,
or he can return it to the time which he wishes the machine to be
at its maximum current.
Toggle switch 68 is a conventional radio type toggle switch which
cuts off after the shaft 61 has been returned to zero position.
With indicator 73 and knob 69 in the positions shown in FIG. 5, the
shaft is in its zero position.
Timers other than the one outlined above may be used with the sleep
inducing machine of this invention as timer attenuators. The above
is given only as representative of one suitable timer.
By making the maximum resistance elements cover arcs of more or
less than 30 degrees of rotation the time of increase from zero to
maximum current and the time of decrease from maximum to zero
current can be made to be periods of time more or less than 5
minutes depending on what time period is found to be most desirable
for a particular application. The increase and decrease time
periods can of course be different where this is determined to be
desirable by making the two maximum resistance elements of
different degrees of arc.
A timer attenuator can also be used which will allow present
fluctuations of current during the running of the sleep inducing
machine.
While the invention has been described in relation to certain
preferred embodiments thereof, it nevertheless will be apparent to
those skilled in the art that certain modifications may readily be
made within the scope of the principles disclosed. Therefore, it is
intended that the scope of the invention be defined and limited
only by the appended claims.
* * * * *