Improvements in the Method of Producing Alternating Electric Currents.
Year: 1890

page_text: COMPLETE SPECIFICATION.
Improvements in the Method of Producing Alternating Electric
Currents.
I, MAHLON S. CONLY of 46, 53rd Street, Chicago, State of Illinois, United States
of America, Electrician, 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 :-
This invention relates to improvements in the method of producing alternating
electric currents in which the terminals of the battery are reversed in relation to the
terminals of the line circuit in which the alternations are to take effect. The method
which heretofore obtained is objectionable because the alternating current is produced
solely by the change of direction of the flow of the primary current from the battery
through the line circuit beyond the local circuit, which, in effect, is merely the
carrying to a greater distance of the primary current of the local circuit, to
accomplish which a large number of cells must necessarily be employed in order to
gain sufficient electro motive force to overcome the resistance of the line; besides
which, in all such arrangements, the electro-static effects, commonly known as the
"kick "of the telegraph key, occur at each reversal of the terminals by induction,
causing retardation in the alternations, which effects are well known to be highly
detrimental and various means have been adopted to destroy them.
The prime object of this invention is to produce and develop to the utmost
degree this heretofore useless and detrimental force, whereby a very feeble battery
may produce impulses of a high electro motive force capable of traversing a long
line of high resistance and accomplishing effective work in that line, not possible to
accomplish with alternating currents as heretofore produced, nor directly by the
battery by which these impulses are produced.
Another object is to utilize the static discharge of the local circuit solely as the
alternating currents or impulses for operating the apparatus contained in the line
circuit, to the exclusion of the primary current from the battery heretofore employed
in alternating electric currents.
The object sought by this method is primarily to cause electro-static discharges
produced by opening a short local circuit to traverse the line circuit in high tension
impulses. and secondarily to cause such impulses to travel in alternately opposite
directions so as to operate devices or apparatus included in the line circuit and
adapted to be operated by the alternating current.
This method may be carried out by numerous forms of apparatus, and the
alternating currents may be employed for accomplishing various results, and working
apparatus not necessary to be herein shown or described.
In the drawings I have illustrated in diagram the simplest means known to me for
carrying out my method of producing alternating currents, in which:
Fig. 1. represents the local and line circuits connected in such manner as to cause
the statically discharged current from the local circuit to traverse the line circuit in
one direction, indicated by the arrows therein;
Fig. 2. a similar view showing the line circuit cut out and the local circuit short
circuited, the arrows therein indicating the direction in which the circuit is traversed
by the local primary current; and
Fig. 3. a similar view showing the line circuit again cut in, so as to cause the
statically discharged current from the local circuit to traverse the line in the opposite
direction from that shown in figure 1.
The apparatus illustrated in the drawings may be briefly described as follows, like
letters of reference in the several figures referring to the same parts:
Let A represent a very short local circuit of low resistance including a battery, B,
a helix, C, and flat spring terminals D-E, the terminal D being connected with the
FD071

page_text: helix preferably on the plus side of the battery by means of a short wire, F, and the
terminal E directly with the minus side of the battery by means of the wire G,
the different parts being so proportioned and arranged as to secure the maximum
degree of electro-static self induction.
A second circuit, H, constituting the line (one-half of which may consist of the
earth) for carrying the result to the different instruments to be acted upon, is
provided with a movable terminal, I, at one end and a fixed terminal, J, at the other,
the latter consisting of a block of any good conducting material, both of which
terminals, I and J, are located between and adapted and arranged to be engaged by
the flat spring terminals D-E of the local circuit.
As a means for vibrating the movable terminal H in a line of motion corresponding
with, and so as to make alternate contact with the terminals D-E of the local
circuit A, I prefer to employ an ordinary telegrapher's key, K, or to mount the
terminal I on the end of a key corresponding in construction and operation therewith,
to be operated by hand or otherwise, and if desired, controlled so as to be normally
actuated in one direction by means of a retractile spring L, which latter however
may be dispensed with or another form of spring employed for holding the terminal I
out of engagement with both of the terminals D-E in its normal position, according
to the uses for which my method is employed. The object sought is to cause
electro-static discharges produced by opening the short circuit A, to traverse the
line circuit H in alternately opposite directions, when the movable contact I is
vibrated.
Taking the apparatus in state of rest, as in Fig. 1, the retractile spring L holds
the free end of the lever or key K, to which it is attached, inclined upwardly,
depressing the other end, and causing the terminal I to make contact with the
terminal D of the local circuit, at the same time bending the said terminal D, so
as to break contact between it and the terminal block J of the line circuit.
At the same time the uncontrolled spring terminal E of the local circuit rests upon
and makes contact with the terminal block J. In this state the two circuits are
united into one and the discharge caused by the breaking or opening of the short
local circuit will traverse the line circuit in the direction indicated by the arrows.
The local circuit might be left normally closed, or by a suitable arrangement, left open
when not in use so as to save the battery.
If now, we depress the outer end of the key K, the first effect is illustrated in
figure 2, in which the key is shown in mid-stroke, and both terminals, D-E, of the
local circuit in contact with the block J, thus short circuiting the battery, and causing
the local circuit to hecome electro-statically charged, the direction of the electric current
at this time in the local circuit being illustrated by the arrows in said figure, while
the line circuit H is cut out.
While the short local circuit A is closed, as illustrated in this figure, the helix
thereof becomes electro-statically saturated to a very high degree, the numerous
coils thereof, as is well known, producing a mutual inductive reaction on each other
which become stored therein, and when the local circuit is again opened will trans-
form the quantity current of the local circuit into pulsations of high electro motive
force capable of traversing a long line of high resistance and operating electrical
devices therein when the primary or quantity current of the local circuit alone could
not possibly produce this result.
In figure 3 the key K is shown depressed to its limit, having first allowed the
terminal D of the local circuit to make contact with the terminal J of the line
circuit, and then lifted the terminal E of the local circuit out of contact with the
terminal J of the line circuit and also broken contact between the terminal I carried
thereby and the terminal D with which it was originally in contact.
Thus the line circuit is again introduced into the local circuit uniting both in a
single circuit and at the same time breaking the short local circuit, thereby causing
the resulting electro-static discharge, from the local circuit, to traverse the line
circuit in the opposite direction from that shown in figure 1, as indicated by the
arrows.

page_text: Now, allowing the key to rest, at mid-stroke the local circuit is again closed
and the battery short circuited for an infinitesimally short length of time, but suffi-
cient for it to become electro-statically charged, after which the continued movement
of the key restores the parts to the position first described and shown in figure 1
when the short circuit is again broken, the line circuit again introduced into the
local circuit and the direction of the current again reversed, as indicated by the
arrows in said figure.
Thus it will be seen that at each complete stroke of the key, the line circuit is
twice introduced into the local circuit, the local is twice closed and opened and the
direction of the current through the line is twice reversed, flowing in one direction
when the parts are in the position shown in figure 1, at one end of the stroke, and in
the opposite direction, when the parts are in the position shown in figure 3, at the
opposite end of the stroke, as clearly illustrated by the arrows in the drawings.
The direction of the current indicated by the arrows in figure 2, at which time the
local current is closed, is reverse to the direction indicated when the line circuit is
introduced, that is, toward the battery on the plus side and away from it on the minus
side, which is the natural flow of the electric current, but, as the discharge which
takes place when the line circuits are cut in, is virtually a reaction of the local
current, it traverses the local circuit in the opposite direction regardless of which of
the terminals, D or E, of the local circuit, the key makes contact, the reversal of the
discharge through the line being effected solely by the reversal of contact of the
terminal I with the terminals D-E of the local circuit, and the closing of the local
circuit by contact of the terminals D and E with the fixed terminal J of the line
circuit.
It will be observed that the local primary current is never employed directly in the
line circuit, but only the static discharge resulting from the breaking of the short
circuit thereof; neither is it used as in the primary of an induction coil for generating
effects in an independent or secondary coil, but the results obtained are due solely to
self induced electro-static effects in the local circuit itself. To secure efficiency in
the maximum degree a suitable proportion must exist between the resistance of the
battery and that of the helix E and the wire of the helix be of a size to allow of a
great number of turns, in order to secure to the utmost their mutual inductive
reaction on each other..
Short circuiting or closing the local circuit A between each discharge is also
indispensable in order that complete electro-static saturation of the same may be
effected after each discharge. The effects may be intensified and strengthened by
electro-magnetic induction, if a soft iron core be inserted in the helix, although this
is not necessary to its successful operation, and should not be employed where
extremely rapid vibrations of the key are required, on account. of the comparatively
slow action of magnetism in iron.
Into the line circuit may be introduced any suitable number and forms of apparatus
capable of being actuated by the alternating currents for producing any desired result,
but as neither the form of such apparatus nor the uses to which the alternating
currents may be put form a part of this invention, I have not deemed it necessary to
illustrate any such uses herein, the sole purpose and object of this invention being
the method of producing alternating currents by means of electro-static discharges
regardless of the apparatus employed in such production or the apparatus by means
of which these currents are utilized.
I am aware that prior to this invention alternating currents have been produced by
reversing the terminal contacts of a battery with respect to the terminals of the
circuit in which the alternations are to take effect, but this method is objectionable
for the reasons before stated and the retardations which occur therein in reversing,
which are caused by induction, are the result of a natural phenomena and not of a
direct purpose to produce them, and for that reason numerous devices have been
employed for destroying such inductive effects, while with my invention the direct
purpose is to produce and utilize these heretofore useless and detrimental discharges
to produce an alternating current for the operation of mechanical appliances, and,

page_text: with a weak battery, to traverse a long line of high resistance and do effective work
-therein where the same battery as ordinarily used would be practically useless.
I am not aware that self induced electro-static forces have been heretofore pro-
duced as herein described or made capable of direct utilization or used for trans-
forming a feeble current into pulsations of high electro-motive force, and I therefore
do not limit myself to the particular mechanical arrangement herein described, as
obviously various modifications of and additions to such devices may be employed and
produce the same results.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :--
1. The herein described method of producing high tension impulses, in a line
circuit, the same consisting in first closing a local battery circuit, including a helix,
thereby causing the helix to become electro-statically saturated, then simultaneously
opening the electric circuit and introducing the line circuit therein, thereby per-
mitting the electro-static discharge from the helix to traverse the line circuit,
substantially as described.
2. The herein described method of producing alternating electric currents in a line
circuit, the same consisting in first closing a local battery circuit in which is included
a helix thereby causing the helix to become electro-statically saturated, and then
.simultaneously opening the local circuit, and introducing the line circuit therein,
alternately reversing the terminals of the local with the terminals of the line circuit
after each closing of the local circuit whereby the electro-static discharge from the
helix will traverse the line circuit in alternately opposite directions, substantially as
.described.
αρησ τουν
MAHLON S. CONLY.
Witnesses:
W. R. OMOHUNDRO.
R. C. OмOHUNDRO.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, Agents for the Applicant.