An Improved System of Electrical Communication for Use in Telephony, Telegraphy, and the like.
Year: 1898

page_text: Date of Application, 14th June, 1898- Accepted, 13th Aug., 1898
'
An Improved System of Electrical Communication for Use in
Telephony, Telegraphy, and the like.
I, ALEXANDER TIMOTHY BROWN, of No. 608, W. Onondaga Street, in the City of
Syracuse, County of Onondaga, and State of New York, United States of America,
Mechanical Engineer, 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 an improved system of electrical communication for use
in telephony, telegraphy and the like, and has for its object the production of a
simplified construction of switching devices and arrangement of wiring, whereby any
one of several stations upon the same circuit may be signalled from one or more of
the stations connected to said circuit; and to this end, the invention consists, in the
combination, construction and arrangement of the component parts of the system, as
hereinafter fully described and pointed out in the claims. In describing this inven-
tion, reference is had to the accompanying drawings, forming part of this specifica-
tion, in which, like letters indicate corresponding parts in all the views.
Figure 1 is a diagramatic view of this improved system.
Figure 2 is a diagramatic view of detached parts of one of the end-stations of said
system; the switching device being shown of substantially full size, and in its normal
position.
Figure 3 is a diagramatic view of detached parts of one of the intermediate
stations of the system and a front elevation of a portion of the enclosing case or box
ordinarily used for a magneto-electric machine, the switching device for the station
being shown as operatively arranged in said case or box, and the other illustrated
parts of said station being shown in reduced scale.
Figure 4 is a diagramatic view of detached parts of another of the intermediate
stations of this system; the switching device of said station being shown of sub-
stantially full size and in its normal position.
Figure 5 is a side elevation, partly in section, and partly broken. away, of the
switching device seen in Figure 2, and an enclosing case or box similar to the one
shown in Figure 3.
A A20, Figure 1, represent the line-wires or conductors of a metallic circuit ;
B2 B3 B20, C2 C3 C20, D2 D3 D20, branch conductors leading from the line-conductors;
nd A B C D E¹ stations connected to said line and branch conductors. The
tation A¹ is preferably arranged at one end of the line-conductors A A 20 and is
provided with a responsive device or signal a, a source of electrical energy, as a
nagneto-electric machine a¹, an electrical communicating device, and a switching
levice, all of which parts may be of any desirable form, size and construction. The
lectrical communicating device usually consists of a receiver a², a transmitter a³, an
nduction-coil a, and a battery a5; and the switching device preferably consists of
ixed terminals aº a7 as aº, movable switch-members a¹ all provided with movable
erminals a12 a13, a movable switch-member a14, and terminals (not lettered) engaged
y said member a14,
The line-conductors A A20 terminate respectively at the fixed terminals as a6; the
onductor a15 leads from the terminal a7 to the ground; the conductor ale from the

page_text: line conductor A20 to the receiver 2; and the conductor a17 from the terminal as to a
terminal adapted to be engaged by the switch-member a14 and normally disconnected
therefrom. The responsive device or signal a is connected in circuit with a
conductor a18 leading to the movable terminal 13 and a conductor a19. The switch-
member a14 normally engages terminals forming the terminations of the conductor a!9,
and an additional conductor a20 leading to the terminal a9, which is normally engaged
by the movable terminal (12.
The magneto-electric machine al is preferably designed to furnish an interrupted
current, and is connected in circuit with conductors a21 a22 leading respectively to the
movable switch-member a10, and a terminal normally engaged by the movable switch-
member a14. The secondary and primary windings of the induction-coil a4 are suit-
ably connected to the receiver a², a conductor a23, the battery a5, and a conductor a24;
and the transmitter a3 is connected to said battery and to a conductor 25. The
conductors a23 24 25 terminate at terminals, which are adapted to be engaged by the
movable switch-member a14, and are normally disconnected therefrom for breaking
the circuits to the induction-coil.
The described means for connecting the parts of the electrical communicating and
switching devices for the station A1 is particularly simple and applicable for this
improved system of electrical communication; but it will be understood that said
devices may be otherwise connected if desired, providing the operation of the parts is
not impaired. It will also be understood that the electrical communicating device
may consist merely of a telephone-receiver or any other suitable mechanism.
The stations Bi Ci Di El are respectively provided with responsive devices or
signals b c d e, magneto-electric machines b1 c d e¹, receivers 62 c2 d2 e²,
transmitters 63 c3 d3 e3, induction-coils b4 c4 d4 e4, batteries 65 c5 d5 e5,
terminals 66 67 68 69 612 613, c6 c7 c8 c9 c12 c13, de d7 d8 d9 d12 d13, e6 e7 es en e12 e13,
movable switch-members 610 611 614, c10 c11 c14, d10 dil 14, e10 e11 e14, and con-
ductors 615 616 617 618 610 620 621 622 623 624 625, c15 c16 c17 c18 c19 c20 c21 22 23 24 c25,
d15 16 17 18 d19 d20 d21 d22 d23 d24 d25, and e15 e16 17 18 19 20 21 22 23 24 €25,
constructed and connected similarly to the like parts a, a1, a2, a3, a4, a5, a6, a7, as,
a0, a12, a13, 10, all, a14, a15 a16 a17 a18 a19 a20 a21 a22 a23 a24 a25 of
the station A1, with the exception of the arrangement of the terminals 66 67 68,
c6 c7 c8, do d7 ds, eo et es, and the responsive devices b c d e.
The terminals eo es are respectively connected to the line-conductors A A20, and
at each station B1 C1 D1, said line-conductors are divided into opposite sections. The
terminals b6 c6 d6 are connected to the branch conductors B20 C20 D20, the
terminals 68 c8 are respectively connected to sections of the line-conductors A A20
leading to the station A¹, and the terminal d8 is connected to a section of the line-
conductor A20 leading to the station El. The remaining sections of said line-
conductors A A 20 are connected to additional fixed terminals 620 c26 d20, two
of which c26 26 are formed with two engaging arms. These additional
terminals 620 c26 d26 are normally engaged with the movable terminals 613 C12 d12
and the terminal d26 is connected to one end of the conductor d17. The responsive
device a is preferably operated only by a current of positive polarity, and the
responsive devices b c are operated only by currents of opposite polarity to those for
operating the responsive devices de. The responsive devices b c are therefore shown
as negative, and the responsive devices d e as positive, and it will be understood that
suitable springs, or any other well known means, as counterweights, not necessary to
describe herein, are connected to the hammers or movable parts of said responsive
devices for retracting the same.
The movable switch-members a10 all a14, 610 611 614, c10 cl1 c14, d10 d11 d14,
e10 ell e14, may be operated by any suitable means, and in order that the construc-
tion and operation of this invention may be entirely clear, suitable means is shown
in Figures 2, 3, 4 and 5, for actuating the switch-members a al al, clo cll c
do di d¹. As best seen in Figure 5, the switch-members of each station, as the
one A', and the actuating means for said members are preferably supported by the
enclosing case or box as the one a, for supporting the usual responsive device and

page_text: magneto-electric machine of the telephone-set at said station. The switch-
members 10 all are insulated from each other and preferably rock independently
and reversely on a shaft as projecting inwardly from the inner face of the front
wall of the case (7, as best seen in Figure 5. Suitable springs a 30 formed of
electrical conducting material hold the switch-members 10 11 in their normal
position, and connect the same to the conductors 21 18, and a stop 31 of insulating
material limits their movement when rocked by said springs.
The switch-members 10 all are provided with apertures a arranged out of alinement
with each other, and suitable operating pieces 33 usually formed with pointed ends
are reciprocally movable into said apertures for alining the same and rocking the
switch-members a¹0 all into position to control the direction and polarity of the
current passed to one or both of the line-wires by the magneto-electric machine a¹.
The operating piece corresponding to the station required is held in position by the
operator's finger during the operation of the magneto-electric machine a', and, when
said station has been called, the pressure is relieved from said operating piece, which
is then automatically returned to its normal position by suitable means, as a spring a34,
whereupon the switch-members a 10 all are also automatically returned to their normal
position by the springs a29a30.
The switch-member a¹ is preferably mounted on a suitable spindle projecting
from the inner face of the rear wall of the case or box a27, as best seen in Figure 5,
and is connected to a lever as having one end mounted on the spindle for said
switch-member, and its opposite end extended through an opening in the adjacent
side wall of the case 27 and provided with a hook-shaped extremity a. The
receiver a² is normally engaged with the extremity a3 and depresses the lever 35
against the action of a spring a". When the receiver a² is removed, the spring 37
elevates the lever 35 and thereby rocks the switch-member a14 from its normal
position for completing the local circuit from the battery a³, and the circuit to the
line-conductors from the secondary winding of the induction-coil a¹. As is apparent,
the enclosing case a27 is particularly applicable for supporting the corresponding
switching device of this improved system, but it is obvious that the same may be
otherwise supported if desired. The switching devices of the stations B¹ C₁ D¹ E¹.
are usually supported by the enclosing cases or boxes for their responsive devices and
magneto-electric machines, and in Figure 3, the switching device for station C¹ is.
shown as supported by the enclosing case c27. It is, however, thought unnecessary
to further illustrate and describe the switching devices of the stations B¹ C¹ D¹ E¹,
as said devices are clearly shown diagrammatically in Figure 1, and as it will be
evident to one skilled in the art that the desired operation of said switching devices,
is effected by the telephone-supporting levers and the reversely rocking switch-
members of said devices.
In order that this improved system may be thoroughly understood, its operation
will now be described. As will be clearly pointed out in tracing the circuits, the
responsive devices be are connected in metallic circuit to both line-conductors, the.
responsive devices c d are connected to the line-conductor A20 and to the ground,
and, as previously stated, the responsive devices bc are operated by currents of.
negative polarity, and the responsive devices de by currents of opposite polarity..
If the attendant at station A¹ desires to actuate the negative responsive device b, he
forces inwardly the operating piece 33 corresponding to said station, and thereby.
moves the switch-member a 10 a sufficient distance to disengage the terminal & 12
from the terminal a without disengaging the same from the terminal as. A
negative current is then free to pass from the source of electrical energy a¹ to the
responsive device b. The circuit for said current consists of the negative conductor a²¹,
switch-member a10, terminals a12 us, line-conductor A, branch conductor B²,
terminals 68 612 6º, conductor 1,20, switch-member 614, conductor 619, negative
responsive device b, conductor 618, terminals 613 626, branch conductor B³, line-.
conductor A, terminals e e¹³, conductor e18, positive responsive device e, (not operated
by said current) conductor e10, switch-member e¹, conductor e20, terminals e eles,
line conductor A20, branch conductor D³, terminals dd2 d2, branch conductor D²,

page_text: line-conductor A20, branch conductor C3 terminals 28 12 8, branch conductor C2, line-
conductor A20, terminals a a, conductor a¹8, responsive device a, conductor (19,
switch-member a¹, and positive conductor a2 to the source of electrical energy a¹.
When the attendant at station A¹ desires to operate the responsive device e, the
corresponding operating piece 33 is actuated to reverse the position of the
terminals a¹ a¹³, and consequently a positive current is then passed over the line-
conductor A from the terminal a¹³, and returns over the line-conductor a20 to the
terminal 2 The circuit between the source of electrical energy a¹ and the
responsive device e is identical with that previously pointed out, and it will be
understood that the passing current is incapable of operating the responsive device b.
If the attendant at station A¹ wishes to operate the responsive device c, the
corresponding operating piece q33 is actuated for respectively engaging the
terminals a12a13 with the terminals a6 a7, whereupon a negative current is passed
over the line conductor A20 through the stations C₁ D¹ to the ground and serves to
operate the negative responsive device c.
The circuit between said stations A¹ C¹ D¹ is as follows; from the ground along
the conductor a15, terminals a a¹³, conductor als, positive responsive device a,
conductor 0, switch-member a¹, positive conductor 2, source of electrical
energy a¹, negative conductor a21, switch-member a¹, terminals a¹², a, line-
conductor A20, branch conductor C2, terminals c8 c¹2 c³, conductor c20, switch-
member c¹, conductor c¹º, negative responsive device c, conductor c¹8, terminals c¹³ c7,
and conductor c15 to the ground at station C₁. A portion of the current passes from
the terminal c12 along the terminal 20, branch conductor C³, line-conductor A20,
branch conductor D2, terminals 26 12 do, conductor d20, switch-member 14,
conductor d, positive responsive device d, conductor 18, terminals d¹s d7, and
conductor 15 to the ground at station D'. Said portion of the current is,
however, unable to actuate the positive responsive device d. In order to actuate the
responsive device d and call the station D¹, the corresponding operating piece a33
reverses the position of the terminals a12 13 so that the terminals a 12 a13 are
respectively engaged with the terminals a a. A positive current then flows over
the same circuit, previously pointed out for the passage of the negative current
for actuating the responsive device c, and said positive current actuates the
responsive device d without operating the responsive device c.
The attendant or subscriber at any of the stations B¹ C¹ D' E' is also preferably
able to call any other station, and, in order that this operation may be apparent,
let it be supposed that the station D' desires to successively actuate the responsive
devices a b c e, and that the corresponding operating pieces ds are successively
operated to bring about the desired action of the switching device at said station Di.
As clearly seen in Figure 1, the terminals d12 13 are normally connected respectively
by the switch-member d¹º and the conductor d18, responsive device d, conductor d¹º,
and switch-member d¹, to the negative and positive conductors 21 (122 leading from
the source of electrical energy d¹. When the positive responsive device a, which is
normally in circuit with the line-conductors A A 20, is to be operated, said
terminals d3d12 are respectively engaged with the terminal do and the adjacent
arm of the terminal 20. A positive current, is then passed from the inovable
terminal d¹s over the branch conductor D20, and the line-conductor A to the responsive
device a, and is returned along the line-conductor A20, the branch conductor D2, and
the terminal to the movable terminal d½2. During this engagement of the
terminals 12 ds, the terminal d³ is disconnected from the terminal d, and, con-
sequently, no current is passed to the station E', which is at the opposite side of the
station 11. The positive current for operating the responsive device a also passes
through the responsive device b, but is incapable of actuating the same.
When the negative device b is to be operated, the position of the terminals d¹ dis
is reversed and a negative current passes to said responsive device band to the
responsive device a, over the intervening portions of the line-conductors A A20, and
said current is cut off from passage to the station E¹ at the opposite side of the
station D¹. In operating the responsive device e, the terminal d¹³ is engaged with

page_text: the terminal do and the terminal d¹ is disconnected from the terminal 26 and is
engaged with the terminal ds. A positive current then passes from the terminals d¹³ do
along the branch conductor. D20, and the line-conductor A to the responsive device e
and returns along the line and branch conductors A20 D³ to the terminals 8 d. It
will be understood, however, that as the terminal de is disconnected from the
terminal d, there is no liability of the passage of the current towards the
stations A¹ B¹ C¹ on the opposite side of the station D₁. When the responsive device c
is operated, the terminal №13 is engaged with the grounded terminal d' and the
terminal d¹² is disconnected from the terminal d8 and is engaged with one arm of
the terminal 26, whereupon a negative current passes from the terminals d¹² d20
along, the branch conductor D²; line-conductor A20, branch conductor C³,
terminal c2, and terminal c² to the negative responsive device .c, and thence to. the
ground.
;
The switching devices at the stations B₁ C¹ E¹ operate in substantially the same
manner as the similar devices at the stations A¹ D', and it is thought unnecessary to
fully set forth their operation. It will be particularly understood, however, that the
switching device at the station B¹, when controlling the passage of the positive.
current to the station E' operates to break one of the line-conductors connected to
the station A¹ on the opposite side thereof, in the same manner as the switching
device at the station D¹ operates to break one of said line-conductors.
The electrical communicating devices of the various stations A' B¹ C¹ D' E' are so
arranged that the electrical communication takes place over a metallic circuit
consisting of both line-conductors. As clearly seen at Figure 1, and previously
pointed out, corresponding conductors, as a18 618 cle die ela of the
telephones a2 62 c³ d² e², are connected either to a line-conductor or to a branch
conductor leading from said line-conductor, and the opposite conductors leading from
said telephones are connected by the switch-members a14 14 14 14 el, when moved
from their normal position, and the conductors. a17 b7c17 d17. e17 to the opposite
line-conductor or branch conductors leading from said line-conductor.
It will be apparent that by this system a metallic circuit party-line is produced which
is differentiated from the prior art, in that, by said system a metallic circuit party-line-is
provided in which is placed one or more stations B₁E, each having responsive devices,
and one or more stations C¹ D' each having a ground-tap and a responsive.device therein,.
and that a source of electrical energy a¹ with an optional ground-tap, is placeable in
the branch of the metallic circuit which connects the junction-points of. the
ground-taps of the stations. C¹ D¹ and includes the station or stations B E¹, which
have their responsive devices in the metallic circuit. Should there be more than two
stations which have their responsive devices in ground-taps, then the source of.
electrical energy a¹ with its optional ground-tap is placeable in the branch of. the
metallic circuit which connects the junction-points of. the first and last ground-taps,
and includes the station or stations B₁E which have their responsive devices in the
metallic circuit. From this arrangement of the circuit and its parts,.it will be seen
that the path of the current is controlled to operate the responsive devices, either in
the metallic circuit or in the ground-taps, in the manner shown and described, without:
the necessity of employing resistance devices in the ground-taps to prevent the..
current from short-circuiting to earth over both branches of the circuit, as would be
the case where the source of energy is placed in the branch of the metallic circuit
joining the ground-taps and. excluding the responsive devices in the metallic;
circuit, in which case the responsive devices in the metallic circuit, would be
short-circuited by the ground-taps, unless these taps contained additional and:
high resistance devices, or as would be the case if the source of electrical energy were
placed immediately between two of the stations having their responsive devices
in the metallic circuit, in which case. it would be impossible to actuate the responsive::
devices in the metallic circuit without at the same time actuating, one of the
responsive devices in one of the two ground-taps. In other words, the use of..
all auxiliary devices to control the path of the current is dispensed with by arrangingit
the source of electrical energy, with relation to the circuit and its parts, as herein set..

page_text: forth. The arrangement of the stations, responsive devices and sources of electrical
energy just described, is applicable not only for a private party-line but also for use
as a party-line in connection with a telephonic exchange, in which case the central
office is substituted for one of the sub-stations. This improved system is preferably
of the described construction in order that each station may be capable of calling
any other station, but it is obvious, that, if desired, one station only may be capable
of such operation. It is also obvious that one of the stations of this improved system
may be dispensed with, and that as herein before mentioned a central or telephonic
exchange station may be substituted therefor, which is also connected to a number of
similar or other circuits leading thereto.
The construction of this invention will now be readily understood upon reference
to the foregoing description and, accompanying drawing, and it will be particularly
understood that said invention is not limited to the exact detail construction and
arrangement of the switching or electric-communicating devices, as the same may be
somewhat varied without departing from the spirit of this invention.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I deolare that what I
claim is:
1. A party-line system comprising a metallic circuit, one or more stations having
responsive devices in the metallic circuit, two or more stations each having a
ground-tap and a responsive device therein, a source of electrical energy provided
with an optional ground-tap and placeable in that branch of the metallic circuit which
connects the junction-points of the first and last ground-taps and includes the
responsive device of the station or stations first specified, and telephonic devices at
each station placeable in the metallic circuit, substantially as and for the purpose
described.
2. A party-line system comprising a metallic circuit, two or more stations having
responsive devices in the metallic circuit, two or more stations each having a
ground-tap and a responsive device therein, a source of electrical energy provided
with an optional ground-tap and placeable in the metallic circuit between either
station in the metallic circuit and the ground-tap adjacent thereto, and telephonic
devices at each station placeable in the metallic circuit, substantially as and for the
purpose specified.
3. A party-line system comprising a metallic circuit, two or more stations each
having responsive devices in the metallic circuit, one or more stations having a
ground-tap and a responsive device therein, a source of electrical energy provided
with an optional ground-tap and placeable in the metallic circuit between the
ground-tap having a responsive device therein and either station in the metallic
circuit adjacent thereto, and telephonic devices at each station placeable in the
metallic circuit, substantially as and for the purpose set forth.
4. A system for electrical communication comprising two line-conductors, separate
stations provided with responsive devices operated by currents of different polarity
and connected to the ground and to one line-conductor, additional stations provided
with responsive devices operated by currents of different polarity and connected in
series in metallic circuit, means for passing electric currents of different polarity
over one line-conductor to the stations connected thereto and to the ground, and for
passing currents of different polarity over both line-conductors to the additional
stations, means at said stations for operating the responsive devices of any of the
stations, and switching devices at said stations for controlling the passage and the
polarity of the current, substantially as and for the purpose described.
5. The combination with a circuit having responsive devices connected thereto, a
source of electrical energy, and terminals connected to the circuit; of independently
movable switch-members provided with terminals for engaging the former terminals
and regulating the passage of the current, and an operating piece mechanically con-
nected to each of said switch-members for actuating the same, said parts being
connected, substantially as and for the purpose specified.

page_text: 6. The combination with a circuit having responsive devices connected thereto, a
source of electric energy and terminals connected to the circuit; of rocking switch-
members provided with terminals for engaging the former terminals and regulating
the passage of the current, said switch-members being provided with apertures
normally arranged out of alinement with each other, reciprocating operating pieces
movable into the apertures for actuating said switch-members, and means for auto-
matically returning the switch-members to their normal position, substantially as
and for the purpose set forth.
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