Improvements in Electro-therapeutic Apparatus.
Year: 1892

page_text: Date of Application, 2nd Mar.. 1892-Accepted, 2nd Apr., 1892
JUBLI LELE SPECIFICATION.
Improvements in Electro-therapeutic Apparatus.
1, WILLIAM JAMES HERDMAN, of Ann Arbor, Michigan, United States of
America, Physician, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in and by
the following statement :-
Heretofore in therapeutical electrical apparatus there has been a great variety
of machines for producing and applying electricity in the various ways desirable.
These have usually been accompanied with batteries or electrical generators,
likewise in great variety both as to their amperage and voltage, and also very
different with respect to their variability when in action. Again, the use of the
same apparatus at different times has been liable to vary greatly in its action.
All this has caused a great disparity in the data as to the effect of the electric
treatment upon patients, even where the physical conditions of the patient were
similar. It has also given rise to great uncertainty among physicians as to what
effects might be expected under certain electrical conditions, because the con-
ditions vary so widely, even where they are presumed to be known, as to clothe
the results with great uncertainty. The difficulties may therefore be summed up
and attributed almost solely to the fact that there has been no certainty as to
the electrical conditions existing in the large variety of applications of electricity
for therapeutical purposes. It is the purpose of my invention to overcome these
varying conditions and to place within the reach of physicians an apparatus simple
in its character and adapted for use with any of the various commercial currents to
be found in almost all cities and towns of any considerable size. I would however,
have it understood that it is equally applicable for use with batteries or other
generators.
My invention consists, essentially in providing the machine with a series of
resistances located upon a shunt-circuit closed at its ends into the main lines of
the commercial circuit or circuit from a battery or other generator in such a
manner that the current thus shunted from the main line of the generator passes
constantly through the said unbroken circuit of the resistances. This circuit I will
term the "machine-circuit." Then I provide suitable pole-pieces or electrodes,
and from these pole-pieces or electrodes lines are led to shifting-terminals,
which two terminals may be engaged with any of the said resistances. The
circuit thus completed through the patient I will term the "patients circuit."
Thus by engaging the said terminals with, say, the two adjacent resistances on the
machine and circuit, it is apparent that very little current would be shunted
through the body of the patient; but by shifting one or both of said terminals so
as to embrace more or less of said resistances between them more current will be
shunted through the body of the patient proportioned to the relative impediment
afforded to the passage of the current through the said resistances and the body of
the patient, because if the resistance between the terminals on the main line is
greater than that afforded by the body a larger proportion of current would pass
through the patient than through the said resistances, and vice versa.
In the accompanying drawings,
Figure 1 is a plan view of an apparatus embodying my invention.
Figure 2 is a diagrammatic view illustrating the construction and operation of
aid apparatus, and more clearly demonstrating my invention.
A represents the main-line wires of any commercial circuit, preferably a constant-
otential circuit.
B represents the circuit of my machine, which I term the "machine-circuit "
closed at its ends into the said circuit of the generator.

page_text: bb²² represent a series of resistances, and e c¹ c² another series of resistances..
These are located on the machine-circuit, and are connected in series in said circuit..
Thus might each represent one-tenth of an Ohm resistance, while c c¹² might
each represent one one-hundredth of an Ohm resistance.
D represents the patient's circuit, and is provided with any usual pole-pieces D
by which the patient is brought into the circuit.
d and d' represent switch-levers which are insulated from each other, and which
constitute the terininals of the patient's circuit. They are each arranged to sweep
over the segments corresponding with the different resistances, so that by shifting
the said switch-levers more or less of said resistances may be incorporated between
them. The physician may shift one of the terminals along the segments of the
resistances 62 bringing into the patient's circuit the additional current each time
due to a resistance in the main line of one-tenth of an Ohm until the patient is
receiving nearly the desired quantum, or until the introduction of the current at
such rapid steps becomes obnoxious to him. Then by shifting the lever d¹ along
the terminals co¹² he may increase the current very gradually, due to the intro-
duction at each step of but one one-hundredth of an Ohm of resistance into the
machine-circuit and so gradually bring the current up to the desired standard.
C
In order to adapt the machine for the various purposes required by the physician
in his ordinary practice, I provide the apparatus with means for producing a
canterizing current and also with an induction-coil for the production of interrupted
current. Thus E may represent a cauterizing circuit, being simply a closed shunt-
circuit in lieu of the patient's circuit. It is apparent that when the switch-
levers are brought into position so as to bring all the resistances between
the two terminals the circuit from the main line is shunted directly through the
cauterizing circuit, which affords but little resistance and the cauterizing section e,
which forms a higher resistance than the remainder of the cauterizing circuit, is
heated up to the requisite degree. The degree to which it may be heated may be
regulated in the same way as the strength of the current over the patient's circuit
was regulated by reducing or increasing the resistances on the machine-circuit
between the terminals dd. These resistances, however, which were employed for
the patient's circuit, might be burned out with the greater amperage of current
passed over the cauterizing circuit, and for this reason I prefer to provide the
special resistances E' for use with the cauterizing circuit. They may, if desired,
be arranged so as to be swept by the same switch-levers or terminals d d as
shown.
F may represent an induction-coil for the production of interrupted current and
having the usual vibrator for this purpose. F is its adjustable core, graduated
with a definite scale, so that exact notes may be maintained in the treatment of a
patient therewith.
Fis the primary circuit of the coil. F³ represents the secondary circuit and F
its pole-pieces.. This is likewise so arranged that current shunted through the
induction circuit F may be graduated by shifting the terminals d d².
If desired, a fusible plug or strip G may be introduced into the machine-circuit
for the protection of the resistances should the current from the generator for
any reason become excessive.
It is apparent that with this machine the current from the generator becomes
practically uniform under all circumstances that is to say, if it is any of the usual
commercial currents these currents for the different systems possess uniform charac-
teristics as respects voltage and amperage wherever they are found and if the
current is from a battery an ammeter and a voltmeter brought into the machine-
circuit before using will afford correct and reliable data as to the current from the
generator entering over the machine-circuit. A physician can therefore use the
apparatus with comparative confidence that with a similar adjustment of his
terminals his electrical conditions will always be the same and not only the same in
his own practice but that the conditions will be the same as they were in any
reported case where the data purported to be the same. In this way the machine,

page_text: it is expected will accomplish the production of reliable and definite data and enable
physicians employing similar machines to reproduce the electrical conditions for the
treatment of like cases.
I am not aware that therapeutical electrical apparatus has before been made in
which the machine-circuit has been provided with a series of resistances and closed
at its extremities into the battery or the circuit of any other generator, and in
which reliance is had for the patient's or operator's current upon the shunt from
the machine-circuit of the requisite current required upon the patient's or
operator's circuit without disturbing or interrupting in any way the machine-circuit.
It will be observed that the relative capacity of the series 663 of resistances
to that of the series c c¹ c² is a decimal ratio that is to say the resistance c is
one-tenth of the resistance b. Of course this need not necessarily be the relation
between them, but it is convenient since it enables the use of decimals, units,
tenths, and hundredths in stating the resistances that are employed in any case.
induction or
I have used the terms "patient's circuit" "
operator's circuit.
interrupted circuit" and the canterizing circuit" simply to distinguish the same.
Of course other circuits for other purposes might likewise be employed and all of
them might be comprehended by the term "operator's circuit." being in any instance
the circuit whereby the physician is producing the desired effect upon a patient and
I would have the term "operator's circuit as employed in the claims to be thus
broadly construed. I would also have it understood that instead of the pivoted
switch-levers any other convenient means for connecting the terminals of the
operator's circuit into shunt connection with the machine-circuit whereby more or
less of the resistances may be embraced between them, might be employed.
33
I have found that this machine operates admirably when deriving its current
from the converter of an alternating circuit, but when the induction-coil is to be
employed difficulty may arise in the use of an alternating current, and where
the machine is connected up with the converter of an alternating circuit I would
provide a separate battery for use, from which to derive the machine-current
when it is desired to use the induction-coil.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is :-
1-
1. In an electrical therapeutical apparatus the combination of a main circuit and
a patient's circuit in shunt therewith, two series of resistances, and sweep-arms for
varying the resistance on the shunt circuit, the consecutive resistances on one
of said series varying in a decimal ratio to the consecutive resistances on the
other of said series substantially as and for the purpose described.
2. In an electrical therapeutical apparatus the combination of a machine-
circuit and a patient's circuit in shunt therewith, two series of resistances, in
one of which consecutive resistances vary in amount equal to the sum of a
number of the resistances in the other set, sweep-arms arranged to bring into the
shunt circuit any desired number of said resistances and pole-pieces whereby the
circuit can be closed through the patient, all combined and operating substantially
as described.
3. In an electrical apparatus, the combination of two series of resistances, of
which the consecutive resistances in one series vary in an amount equal to the suni
of the resistances of several of the other series, means for closing the circuit beyond
the resistances, and means substantially as described, for using the two series of
resistance in combination so as to vary gradually through the whole system of
resistance from the lowest to the highest by the difference in resistance between
two consecutive resistances in the series of low resistances, substantially as and for
the purpose described.
4. In a therapeutical apparatus, the combination with a machine-circuit per-.
manently closed from the point of entrance to the point of departure of the current,
the said machine-circuit provided with a series of resistances of a patient's circuit;,.

page_text: an induction or interrupted circuit and a cauterizing circuit, each provided with
terminals, whereby it may be engaged into shunt connection with the machine-
circuit and its current be graduated by bringing more or less of said resistances
between said terminals, substantially as described.
5. In a therapeutical apparatus, the combination, with a machine-circuit per-
manently closed from the point of entry to the point of departure of the current,
said circuit provided with a series of resistances, of a cauterizing circuit adapted
to be connected in shunt with the machine circuit, and special resistances E
arranged to be brought into said cauterizing-circuit and adapted to carry the
increased amperage of current without injury, substantially as described.
Dated this 2nd day of March 1892.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.