IMPROVEMENTS IN THE ART OF TRANSMITTING TELEPHONIC MESSAGES, AND IN CONTROLLING THE GROUND WIRES OF THE CIRCUIT STATION INSTRUMENTS FROM THE MAIN OR CENTRAL STATION, THE APPARATUS AND OTHER MECHANISMS AND APPLIANCES THEREFOR, AND THEIR COMBINATION."
Year: 1880

page_text: LETTERS PATENT to Anthony Michael Frankenberg, of the City and County
of Baltimore, in the State of Maryland and United States of North
America, Electrician, for an Invention of "IMPROVEMENTS IN THE ART OF
TRANSMITTING TELEPHONIC MESSAGES, AND IN CONTROLLING THE GROUND
WIRES OF THE CIRCUIT STATION INSTRUMENTS FROM THE MAIN OR CENTRAL
STATION, THE APPARATUS AND OTHER MECHANISMS AND APPLIANCES
THEREFOR, AND THEIR COMBINATION."
PROVISIONAL SPECIFICATION left by the said Anthony Michael
Frankenberg at the Office of the Commissioners of Patents on the 14th
December 1880.
ANTHONY MICHAEL FRANKENBERG, of the City and County of Baltimore, in the
State of Maryland and United States of North America, Electrician. " IMPROVE-
MENTS IN THE ART OF TRANSMITTING TELEPHONIC MESSAGES, AND IN CONTROLLING
THE GROUND WIRES OF THE CIRCUIT STATION INSTRUMENTS FROM THE MAIN
OR CENTRAL STATION, THE APPARATUS AND OTHER MECHANISMS AND APPLIANCES
THEREFOR, AND THEIR COMBINATION."
My Invention relates to certain improvements in the art of transmitting sound and
messages by the use of the telephone, and embraces a system of district or other
telegraphs or telephones, in which the communicating instruments of all the circuit
stations are entirely controlled in their functions or use and adjustments by means
of a battery and a transmitter at the main or central station.
My object is to give complete control of all the instruments of the subscribers,
whether such instruments are in or out of use to the operator at the main station
by means under his control. This, so far as I know, has never been done by any
district or other telegraphy or telephone system. By this complete control over
the working of all the circuit instruments by the operator at the main station, all
annoyances arising from neglect or inexperience of the subscribers in the use of
their communicating instruments are avoided, since there can be no derangement
of such instruments either by accident or design on the part of subscribers that
cannot be corrected from the main station by means there under the control of the

page_text: operator in charge, for while the subscribers have all necessary appliances for using
their instruments, such appliances are nevertheless within the supreme control of
the operator and his transmitter at the main station.
My Invention also embraces a new organization by which any one bell or signal
in an electrical circuit composed of a number of bells or signals can be rung or
signalled without ringing or signalling the others, and by which any one of such
stations can call or signal the main station without said call or signal being heard
at any of the other stations on the line.
Under my central controlling system the operator at the main station can shunt
out at will by operating the mechanism at the circuit stations the push-buttons at
all these stations, and by so doing he thereby prevents all interference with the
operations of the mechanisms of the circuit stations while said mechanisms are
operated from the main station, for the purpose of allowing the central operator to
call or signal any particular circuit station. At the same time this mechanism
operates a device by which the instrument is placed in condition to make ground
connections for the purpose of cutting off all stations beyond it and the main
station, or all the stations between the main station and the circuit station in
communication with another circuit station. While this has been done in the
present system yet it has objections, in the fact that the operators at any of the
circuit stations may, by neglect or otherwise, put on or leave on this ground con-
nection to the annoyance of those properly communicating. But by my central
controlling system this improper use of the ground connections is placed beyond the
control of the circuit stations by the ground wires being under direct control from
the central station, while being only under partial control by the circuit stations
for proper use.
From the main station, under my new system, the operator there can cut off or
disconnect the ground wires of all the circuit stations to restore the line to its
normal condition for operation. This is made necessary in case the ground wires of
any one or more of these stations may have been left on by inadvertence or purposely,
and thus not leave it solely under the control of the operator at the circuit station,
as heretofore done. In the event of any derangement of the instruments, my
complete control from the main station allows all the instruments to be adjusted
throughout the circuit by means of mechanism in the instruments at each circuit
station, operated and controlled from the main station, and thus adjust all the
instruments throughout the line to an initial point.
The complete central control of the circuit instruments is obtained by means of
a transmitter of novel construction in connection with a single battery giving off
three several distinct degrees of tension or power, or having the effect of three
distinct batteries of different degrees of power, and in which the several degrees of
tension are used for the purpose of effecting certain separate and combined results
in the working of the telephone circuit.
The transmitter by its novel construction has separate connection with each of
the circuit instruments through the battery by a corresponding number of push-
buttons, all except one of which are used for ringing any of the call bells at the
circuit stations, and in which the full force of the battery is brought into action.
This single push button is used to bring only a portion of the battery into action
to place the instruments of all the stations to an initial point.
The push-buttons of the circuit station instruments are put in condition for
calling or signalling the main station by means of the transmitter being brought
in connection with that part of the battery giving the least of the three degrees of
tension or power.
The second section of the battery, or that part giving a degree of tension or
power greater than that just mentioned, but less than the whole tension, is used
for operating or controlling the working devices of the circuit station instruments
which operate the circuit closers; while the ringing of the bell or giving a signal
at any one of the stations is effected by combining the several degrees of tension
of the battery, and using them as a whole or single battery.

page_text: I also use the combined tension of the battery for the purpose of working the
mechanism of the circuit instruments after all the instruments have been brought
to the initial point. My Invention not only comprehends a new transmitter, but
a new organization of circuit station instruments adapted for being operated by
such transmitter, and it will be understood that the latter is located at the central
or main station, while the instruments are each located at stations within the
telephone circuit.
It will also be understood that said transmitter is used in connection with suitable
appliances, such as switches, telephones, and an indicator, to show the condition of
the instruments on the line at the main station, but as such appliances and their
functions are well understood, it is deemed unnecessary to illustrate and describe
these in detail.
The operating mechanism of the transmitter is mounted upon a suitable support,
and consist of a series of push buttons corresponding in number to the connected
stations, and arranged for convenience in a circular form upon said support, and
with their stems pressing upon springs arranged radially upon the underside thereof.
These springs are in double sets, one of each set being secured to a segment, and
extending inward, while the other spring of the set is secured to like segments and
extends outward so as to make a contact with an intermediate segment and to
overlap the outer circle of springs, the free ends of which are brought to bear upon
the inner springs by pressing on the buttons. The outer segment is connected
with the entire battery, and receives its full tension or power. The intermediate
segment is connected with said battery, and receives only a portion of its full
tension or power, while the inner segments are connected with insulated discs
arranged in a circle upon the support.
A vertical shaft carries an arm provided with a roller which describes a circle as
the shaft is revolved coincident with the insulated discs, and is brought in contact
therewith to make and break the circuit. This arm may be operated by hand or
by a clock movement, by which the shaft and arm are rotated, and which may be
set in motion by means of a special push-button, which clockwork also serves as a
stop to arrest the arm at the desired points.
The revolving arm is connected with the line wire and with that section of the
battery having the least degree of tension or power for the purpose of allowing the
circuit stations to call or signal the main station. Connection is also made between
the intermediate segment and the outer ranges of radial springs for the purpose of
working the mechanism, and by depressing the proper button when the arın is
passing over the unison disc it prevents the instruments from passing the unison -
point, and while said arm is making one revolution over the discs it brings all the
instruments that are out of adjustment to the initial point. This is done by the
combined tension of the two battery sections having the least tension or power.
The circuit for allowing the stations to call the main office is made from any one
of such stations through the line wire to the transmitter post at the main station,
passing thence to the revolving arm, one of the discs and segments to that section
of the battery having the least tension or power.
The circuit connection for propelling the mechanism in any one of the call
apparatuses at the circuit stations is made from the battery to one of the segments,
thence by the contact springs to the other segments which connect with the discs
which are brought into connection with the main line through the revolving arm.
Through the medium of a binding post and wires a segment and spring connection
made for ringing the bells or giving the signals and causing the mechanism of
the circuit instruments to pass the initial points, and thus place all the instruments
in condition for operation by means of the combined tension or power of the whole
battery. In operating this transmitter the depression of the proper buttons brings
the upper spring against the lower, which being thus pressed down breaks the
contact of the inner spring with the intermediate segment and makes the connection
with the entire battery to give the signal at any particular station. In the normal
condition of the transmitter the rotatable arm stands upon that disc which is in

page_text: connection with that portion of the battery having the least degree of tension, and
this is the condition to allow the circuit stations to call the main office. The
position of this arm is the point at which all the instruments throughout the line
are in condition to make the ground connections. That is to say, the arm is out of
the circuit which disconnects the line wire from the batteries. The main line is
then switched to the telephone at the main station by means of a switch, such as is
used in telephone systems, thus placing all the instruments throughout the circuit.
in position to make their ground connection.
The push button circuit making discs will be properly numbered to correspond
with the number of stations. These communicating circuit instruments are
provided with the ordinary call bells, their operating electro magnets and
telephones. Each of these instruments is provided with mechanism for operating
the circuit closers and a unison device, the latter bringing all the instruments to an
initial point.
This mechanism is operated by an electro magnet through the medium of its
armature, and consists of several hinged circuit closers, their free ends extending
over insulated contact points. The first of these insulated points acts with the first
circuit closer to shunt out the bell magnet. The second circuit closer acts with the
second insulated point to shunt out the push button of this instrument, and the
third circuit closer connects with a lever of the switch and acts with the third
contact or spring for the purpose of making the ground connection. These
circuit closers are operated by a tappet shaft, the tappets being arranged to operate
said circuit closers at certain points; one of the tappets lifts the first circuit closer
from its contact point and puts the bell magnet in the circuit and in condition to
ring the bell.
Another tappet lifts the second circuit closer from its contact point to place the
push button and telephone in the circuit. This last named tappet also lifts the
third circuit closer to bring it in contact with the third contact point to make the
ground connection. It will be seen that while this tappet lifts the second and
third circuit closers at the same time it does not release them at the same time, by
reason of their unequal length, the third short one being the first to fall; the push-
button is thereby kept in circuit after the ground connection is broken, while the
second longer circuit closer is held up a somewhat longer time to keep the push
button and telephone in circuit while the arm of the transmitter is passing to a
point to throw off the ground wire and connect the battery of the least tension
with the line for the purpose of allowing the main station to be called.
The second circuit closer being held up to keep the telephone and the push
buttons in the circuit, otherwise these parts would be shunted out. The circuit
closers are connected with the line through the medium of the metallic frame of
the instrument, while they also connect with the electro bell magnet through
suitable wire, and both the magnets are connected with the line by wire and
binding post.
The circuit closers are operated by the armature lever engaging a toothed wheel
on the tappet shaft, and a retracting spring for said lever to rotate said shaft, and
to prevent the latter from turning backward it is provided with a ratchet and
check pawl.
The unison is effected by this tappet shaft by means of a third
tappet, acting upon the end of an arm pivoted to the frame of the instrument and
constantly pulled upward by a spring against an adjustable set screw, so that as
the tappet shaft is revolved by the action of the armature lever, this last tappet is
brought against the free end of the said arm and is thereby arrested, and as that
part of the battery by which this is effected has not sufficient power to cause the
tappet to pass said arm, the initial point of all the instruments of the circuit is in
this way effected.
In order to pass this point the entire tension of the battery is brought into use.
I have described one of the tappets as operating the first circuit closer, but it will
be understood that the position of this tappet can be adjusted on its shaft so
as to cause it to raise the circuit closer to suit the instruments at any station

page_text: corresponding with the number of the insulated discs. The bell and the electro
magnet for ringing the same are arranged and operated substantially as is ordinarily
done.
Referring to the manner in which I effect and control the ground connections,
it is important to observe that the third circuit closer is brought into action to
make the contact at a certain time, that is, while the tension of the retracting
spring is actuating the armature lever and revolving the tappet shaft, and that
at this time all the instruments are placed in condition to enable them to make a
ground connection by means of a suitable switch. At the next attraction of the
armature the tappet shaft will be revolved and to release the third circuit closer,
and thereby break the ground connections at the stations and put the line in a
normal or perfect working condition.
Should any of the switches of the stations be left on. all the instruments can be
brought to a point where the line may be used for telephoning without the use of
the ground wires. I mean by this that the line wire is brought to a perfect
working condition by bringing the revolving arm of the transmitter in con-
tact the proper disc, and that this has the effect of putting on the working
battery and thereby moves the tappet shaft forward and releases the third
circuit closer, and thus disconnects the ground wire from each of the circuit
instruments.
To use the telephone at any station the switch lever is shifted to the right or
to the left to raise the circuit closer which cuts in the telephone and puts on the
ground wire, and the communication is made the same in either direction, the
telephones being in their proper connection with the instrument. I have stated
that a single battery having different degrees of tension or power is used in
connection with my transmitter and call apparatus, and for convenience I may
designate these several degrees of tension as 1, 2, and 3, with which the
transmitter wires are separately connected and in which 1 has the least tension,
2 the tension of 1, and 2 and 3 includes the whole force, and thus lessens the
expense of obtaining power; and while I prefer this construction yet I do not
wish to confine myself to such form but may use three separate batteries.
each station instrument I employ a magnet indicator, the needle deflections of
which will show whether the line is in use or not.
With
In operating from the central station to call, say, No. 5, the operator presses on
the corresponding push button. This puts on the whole battery. The rotating arm
is then released by pressing on the proper button or revolved by hand, causing it to
pass over the first insulated discs, and thereby opens and closes the line or circuit,
and in passing the button causes the bell to be rung at that station.
This being done the arm is carried to the second insulated disc to receive the
reply from the local station, after which the said arm is again carried round to the
insulated point to place all the instruments in condition to use the ground wire.
The telephone is then switched in at the main and circuit stations, and the two can
communicate by telephone. After this is through, the line is again switched to the
transmitter and the revolving arm carried to the first disc, and in doing so dis-
connects the ground wires of the circuit stations, leaving the line in its normal
condition.
This disconnection of the ground wire is made by bringing the revolving arm in
contact with the third disc which, as before stated, connects the battery sections 1, 2,
with the line, thereby moving the tappet shafts of all the station instruments
forward one tooth, and thereby releasing the third circuit closer and breaking the
ground connection. In making a revolution over the insulated discs, the arm in
passing from one insulated point to the others opens and closes the circuit as stated,
and by so doing operates the mechanism of the circuit stations, and thereby cuts
out the push button at each of these stations and prevents all interference with the
line, thus giving complete control of the whole system to the operator at the main
station. In this operation of the revolving arm all the relative push buttons of the
circuit stations are shunted out after said arm is moved beyond its normal point,

page_text: which is the second disc, and which connects the battery section 1 to allow all the
outlying stations to call or signal the main office without disturbing the mechanisms
of any of such stations as before stated. When the third disc is in connection
with the rotating arm the full battery power is brought in connection with the
main line, which is also in connection with said arm, in which case the tappet
shafts of the circuit stations are passed beyond the unison points by the force of
the full battery, leaving all of said instruments in condition to be again brought to
a unison point by the working battery sections 1, 2. The transmitter has another
function in connection with battery sections 1, 2, which is to prevent the tappet
shafts of the instruments that are in unison from passing such point during the
rotation of the transmitter arm over the discs to bring those instruments that are
out of unison up to the unison point by disconnecting the full battery power and
connecting sections 1, 2, thereof with the main line.
The third circuit closer is lifted by the back stroke of the armature lever, and is
dropped by the forward stroke thereof. The lifting of this circuit closer is to bring
it in contact with a spring for connecting the switch lever with the ground wire
to make the ground connection and while there is no battery on the line, and the
dropping of said circuit closer takes place when the battery is again applied for the
purpose of disconnecting the switch from the ground wire, and thus breaking the
ground connection. The ground connections are made at each and all the circuit
stations at the same time for the purpose of allowing any one of the circuit stations
to use the ground wire. The effecting of the unison of all the circuit station instru-
ments is done by the operator depressing the push button which disconnects the
whole battery and connects its stations 1, 2, after which the rotating arm of the
transmitter is caused to revolve, and in passing over in contact with the discs the
several instruments are thereby brought to an initial point, but cannot pass it until
the arm is again brought in contact with proper disc after the said button is
released.
It is obvious that the number of teeth in the wheel of the tappet shaft and the
push buttons of the transmitter must correspond to the number of stations, but said
wheel must also have two additional teeth to correspond with the movement of the
rotating arm from its insulated point to the normal point, and from there to pass
the unison point, the movement given the wheel by these additional teeth being
equal to the movement of the arm between the points stated. The circuit calling
apparatus is enclosed in a case or cover, the bell and the magneto-indicator only
being exposed.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Anthony Michael Frankenberg in the Great Seal Patent Office on
the 30th March 1881.
ANTHONY MICHAEL FRANKENBERG, of the City and County of Baltimore, in the
State of Maryland and United States of North America, Electrician. "IMPROVE-
MENTS IN THE ART OF TRANSMITTING TELEPHONIC MESSAGES, AND IN CONTROLLING
THE GROUND WIRES OF THE CIRCUIT STATION INSTRUMENTS FROM THE MAIN
OR CENTRAL STATION, THE APPARATUS AND OTHER MECHANISMS AND APPLIANCES
THEREFOR, AND THEIR COMBINATION."
I have made certain improvements in the art of transmitting sound and messages
by the use of the telephone. My Invention embraces a system of district or other
telegraphs or telephones, in which the communicating instruments of all the circuit
stations are entirely controlled in their functions or use and adjustments by means
of a battery and a transmitter at the main or central station. My object is to give
complete control of all the instruments of the subscribers, whether such instruments
are in or out of use, to the operator at the main station by means under his control.
This so far as I know has never been done by any district or other telegraphy or
telephone system. By this complete control over the working of all the circuit
instruments by the operator at the main station, all annoyances arising from
neglect or inexperience of the subscribers in the use of their communicating instru-
ments are avoided, since there can be no derangement of such instruments either
by accident or design on the part of subscribers that can not be corrected from the
main station by means there under the control of the operator in charge, for while
the subscribers have all necessary appliances for using their instruments, such
appliances are nevertheless within the supreme control of the operator and his
transmitter at the main station. My Invention also embraces a new organization
by which any one bell or signal in an electrical circuit composed of a number of
bells or signals can be rung or signalled without ringing or signalling the others,
and by which any one of such stations can call or signal the main station without
said call or signal being heard at any of the other stations on the line. Under my
central controlling system the operator at the main station can shunt out at will,
by operating the mechanism at the circuit stations the push buttons at all these
stations, and by so doing he thereby prevents all interference with the operations
of the mechanisms of the circuit stations while said mechanisms are being operated
from the main station, for the purpose of allowing the central operator to call or
signal any particular circuit station. At the same time this mechanism operates
a device by which the instrument is placed in condition to make ground con-
nections for the purpose of cutting off all stations beyond it and the main station,
or all stations between the main atation and the circuit station in communication
with another circuit station. While this has been done in the present system yet
it has objections in the fact that the operators at any of the circuit stations may by
neglect or otherwise put on or leave on this ground connection to the annoyance
to those properly communicating. But by my central controlling system this
improper use of the ground connections is placed beyond the control of the circuit,
stations by the ground wires being under direct control from the central station,
while being only under partial control by the circuit stations for proper use.
From the main station under my new system the operator there can cut off or
disconnect the ground wires of all the circuit stations to restore the line to its
normal condition for operation. This is made necessary in case the ground wires
of any one or more of these stations may have been left on by inadvertence or
purposely, and thus not leave it solely under the control of the operator at the

page_text: circuit station as heretofore done. In the event of any derangement of the instru-
ments my complete control from the main station allows all the instruments to be
adjusted throughout the circuit by means of mechanism in the instruments at each
circuit station operated and controlled from the main station, and thus adjust all
the instruments throughout the line to an initial point. The complete central
control of the circuit instruments is obtained by means of a transmitter of novel
construction in connection with a single battery giving off three several distinct
degrees of tension or power, or having the effect of three distinct batteries of
different degrees of power, and in which the several degrees of tension are used
for the purpose of effecting certain separate and combined results in the working
of the telephone circuit. The transmitter by its novel construction has separate
connection with each of the circuit instruments through the battery by a corre-
sponding number of push buttons, all except one of which are used for ringing
any of the call bells at the circuit stations, and in which the full force of the battery
is brought into action.
This single push button is used to bring only a portion of the battery into
action to place the instruments of all the stations to an initial point. The push
buttons of the circuit station instruments are put in condition for calling or
signalling the main station by means of the transmitter being brought in con-
nection with that part of the battery giving the least of the three degrees of tension
or power. The second section of the battery or that part giving a degree of tension
or power greater than that just mentioned, but less than the whole tension, is used
for operating or controlling the working devices of the circuit station instruments
which operate the circuit closers, while the ringing of the bell or giving a signal
at any one of the stations is effected by combining the several degrees of tension
of the battery and using them as a whole or single battery. I also use the
combined tension of the battery for the purpose of working the mechanism of the
circuit instruments after all the instruments have been brought to the initial point.
Referring to the accompanying Drawings:-
-
Figure 1 represents a top view of a transmitter used in the central or main
station with battery connections, and two of the communicating instruments at two
of the circuit stations, and a part of the telephone line connecting these instruments
with the transmitter at the main station; Figure 2 represents a side elevation of one
of the call or circuit station instruments, one of the side plates being removed;
Figure 3, a bottom view showing the switch for cutting in the telephone and
putting on the ground wire and the working wire connections; Figure 4 represents
a top view of the mechanism for operating the circuit closers, and a part of the
device for operating the unison for bringing all the circuit station instruments to
an initial point; Figure 5, a cross section of the instrument taken on the line x, x,
Fig. 4; Figure 6, a detail side view of the unison devices; Figure 7, a detail top 4
view of the insulated contact points for the circuit closers; Figure 8, a detail front
view of the parts shown in Fig. 7; Figure 9, a detail side view of the device for
operating the driving shaft of the mechanism; Figure 10, a detail of one of the
circuit closers for making the ground connection; Figure 11, a vertical section of
the transmitter; Figure 12, a bottom view of the transmitter; Figure 13 represents 4
a diagram showing the different wire connections in a circuit instrument in
connection with a transmitter and battery at the main station by means of the line;
and Figure 14 represents in diagram so much of the transmitter as shows the
relative electrical relation of the disc c², the rotating arm D, the segments 61, 67,
and 6, the spring a³, and the binding post G3, as illustrating the connection of said 5
disc and main line with the full battery for passing the tappet shafts k of the
circuit station instruments beyond the unison point; Figure 15 represents a similar
view showing the electrical relation of the same parts in connection with the
segments 61, 62, and 610, the springs a, a³, and the binding post G², as illustrating
the connection of the disc c² with the working battery sections Q, R, by the 5
button B² for bringing all the instruments to the unison point; and Figure 16
represents a similar view showing the electrical relation of the disc c in connection

page_text: with the segments 61, 62, and b, the springs a and a', the rotating arm D, and one
of the buttons B, for operating the tappet shafts k of all the circuit station
instruments by rotating the said arm over said discs, and in which the depression
of any one of said buttors B will ring the call at the desired station. To enable
those skilled in the art to which my Invention relates to construct and use my
Invention, I will proceed to describe the same in connection with the Drawings
which constitute part of this Specification. My Invention not only comprehends a
new transmitter, but a new organization of circuit station instruments adapted for
being operated by such transmitter. In Figure 1 of the Drawings I have shown
the transmitter in connection with two circuit station instruments and a battery,
and it will be understood that the transmitter is located at the central or main
station, while the instruments are each located at stations within the telephone
circuit. It will also be understood that the transmitter is used in connection with
suitable appliances, such as switches, telephones, and an indicator to show the
condition of the instruments on the line at the main station; but as such
appliances and their functions are well understood, it is deemed unnecessary to
describe or represent these things. The operating devices of the transmitter are
mounted upon a suitable carrier or support A, and consist of a series of push
buttons B corresponding in number to the connected stations, and arranged for
convenience in a circular form upon the upper face of the support, and with their
stems passing through said support and pressing upon springs arranged radially
upon the underside of said support, as shown in Figs. 11 and 12. These springs
are in double sets, one a of each set being secured to a metallic segment b at or
near the outer edge of the support and extending inward, while the other spring at
of the set is secured to metallic segments 6' nearer the center of the support, and
extends outward so as to make a contact with an intermediate metallic segment b²,
and to overlap the outer circle of springs, the free ends of which have contact
points a², Fig. 11, which are brought to bear upon the inner springs al by.
pressing on the buttons B. The outer metallic segment b is connected with the
entire battery, and receives its full tension or power. The intermediate metallic
segment 62 is connected with said battery, and receives only a portion of its full
tension or power, while the inner metallic segments 6¹ are connected with metallic
insulated discs c arranged in a circle upon the upper side of the support, and for
convenience within an annular recess therein. A vertical central shaft C carries an
arm D, the outer end of which is provided with a roil d, Fig. 11, which describes a
circle as the shaft is revolved coincident with the insulated metallic discs, and is
brought in contact therewith to make and break the circuit.
For this purpose the arm D may be operated by hand, but a spring and gear
motor may be used by which the vertical shaft C and arm D are rotated, and
which may be set in motion by means of a special push button E, which clock
work also serves as a stop to arrest the arm at the desired points. The connection
of this horizontal revoluble arm with the line wire F is made through the binding
post G and wire b³, Figs. 1 and 12, to the motor or frame. I use one of these
metallic insulated discs c¹, Figs. 1 and 11, to form a connection by the arm D with
that part of the battery having the least degree of tension or power by means of
the metallic segments band the wire 6, Fig. 12, leading to the binding post G₁ for
the purpose of allowing the circuit stations to call or signal the main station. The
binding post G² (Figs. 1, 12, and 13) is connected to the intermediate segment 62
and to one of the outer ranges of the radial springs a by the wires 66, Fig. 12, for
the purpose of working the mechanism, and by depressing the button B², Fig. 1,
when the arm is passing over the unison disc c², Fig. 1, it prevents the instruments
from passing the unison point, and while the arm is making one revolution over
the discs, it brings all the instruments that are out of adjustment to the initial
point. This is done by the combined tension of the two sections of the battery
having the least tension or power.
The circuit for allowing the circuit stations to call the main office is made from
any one of such stations through the line wire F, Fig. 13, to the transmitter post G

page_text: at the main station, passing thence to the revolving arm D through its post C and
through the disc c¹ to the segment 63, and the wire b' to the binding post G¹, thence
to that section Q of the battery having the least tension or power. The circuit
connection for propelling the mechanism in any one of the call apparatuses at the
circuit station is made from the battery sections Q, R, to the binding post G³,
through the wire 68, Fig. 12, to the segments 68, thence by the contact springs a, a¹,
to the segments 61 which connect with the disc c, which are brought into connection
with the main line F through the arm D, its post, the wire be to the binding post G,
Fig. 12. The fourth binding post G³ is connected to the outer segment b by the
wire bs for ringing the bells, and it is also connected to the segment 67, Fig. 12,
by the wires b, and the inner spring a³ rests on said segment 67 for the purpose
of ringing the bells or giving the signals and causing the mechanism of the circuit
instruments to pass the initial points, and thus place all the instruments in condition
for operation by means of the combined tension or power of the whole battery. In
operating this transmitter the depression of the buttons B brings the lip a² of the
upper spring a against the lower spring a', which being thus pressed down breaks
the contact of the inner spring with the intermediate segment 62, and makes the
connection with the entire battery to give the signal at any particular station. In
the normal condition of the transmitter the rotatable arm D stands upon the
metallic disc c, as shown in Figs. 1 and 11, which is in connection with that
portion of the battery having the least degree of tension, and this is the condition
to allow the circuit stations to call the main office. The position of this arm D,
shown in dotted lines in said Figure 1, is the point at which all the instruments
throughout the line are in condition to make the ground connections, that is to
say, such position of the arm D is between the discs c³, c, and is thus out of the
circuit which disconnects the line wire from the batteries. The main line is then
switched to the telephone at the main station by means of a switch not shown, but
such as is used in the telephone systems, thus placing all the instruments throughout
the circuit in position to make their ground connection. The push buttons B and
the circuit making discs c will be properly numbered to correspond with the
number of stations. Having described the controlling instrument and its con-
nections with the battery of the main station I will now describe the communi-
cating circuit instruments, the functions of which are entirely controlled thereby.
These instruments are provided with the ordinary call bells, their operating electro
magnets and telephones. Each of these instruments is provided with mechanism
for operating the circuit closers and a unison device, the latter bringing all the
instruments to an initial point. This mechanism is operated by an electro magnet M
by means of the armature H, and consists of circuit closers 1, 2, 3, one end of each of
which is hinged with their free ends extending over insulated contact points 4, 5, 6,
Figs. 7, 8, and 13, secured to a sill 20. One of these insulated points 4 acts with
the circuit closer to shunt out the bell magnet M2 by wire connections 7, shown
in Figs. 7, 8, and 13.
The circuit closer 2 acts with the insulated point 5 to shunt out the push
button I of this instrument by means of the wire 8 and the binding post 81,
Fig. 13, and a third circuit closer 3 connects with the lever J of the switch by the
wire 9, as in Figs. 2, 4, 13, and acts with an insulated contact point or spring 6
of the sill 20 for the purpose of making the ground connection by the wire 10,
Figs. 7, 8, and 13. These circuit closers are operated by a tappet shaft k
mounted parallel with the sill in bearings in the side plates of the instruments, the
tappets being arranged to operate said circuit closers at certain points. The
tappet 11, Figs. and 5, as the shaft is revolved, lifts the circuit closer 1 from its
insulated contact point 4 and puts the bell magnet M2 in the circuit and in
condition to ring the bell. The tappet 12, as the shaft is revolved, lifts the circuit
closer 2 to separate it from its insulated contact point 5, and allows the push button
I and telephone to be placed in the circuit.
This last named tappet 12 also lifts the circuit closer 3 to bring its insulated
point 31, Figs. 10 and 13, in contact with the insulated contact point or spring 6

page_text: to make the ground connection through the wire 10 to the binding post 13,
Figs. 1 and 13. It will be seen that while this tappet 12 lifts the two circuit
closers 2 and 3 at the same time, it does not release or drop them at the same time by
reason of their unequal length, the short one 3 being the first to fall; the push
button I is thoreby kept in circuit after the ground connection is broken, while
the longer circuit closer 2 is held up a somewhat longer time to keep the push
botton I and the telephone in circuit while the arm D of the transmitter is passing
to a point to throw off the ground wire 10 and connect the battery of the least
tension with the line for the purpose of allowing the main station to be called.
The point at which the ground wire 10 is thrown off from the main line is the
disc c³, Fig. 1, and it is while the arm D is passing from disc c³ to disc c² that the
circuit closer 2 is held up to keep the telephone and the push buttons I in the
circuit, otherwise these parts would be shunted out.
The circuit closers connect with the line F by the metallic frame Z of the
instrument, while they also connect with the electro bell magnet by the wire 14,
Fig. 13, while both the magnets connect with the line by the wire 14 and binding
post 15, Figs. 1 and 13. The operation of the circuit closers which I have just
described is effected by means of a driver, consisting of a lever K carrying the
armature H, and terminating at its lower end in a forked or segmental pawl 7,
adapted to embrace and engage with a toothed wheel L on the tappet
shaft and cause it to revolve by the vibrations of the lever K produced by the
action of the electro magnet, the armature, and an adjustable retracting spring,
Fig. 2. In this action the lever acts as a double pawl, and pulls and pushies at
each vibration of the lever, and thus revolves the tappet shaft. To prevent the
tappet shaft from turning backward under the vibrating action of the driver it is
provided with a ratchet wheel m, into which a check pawl n, Fig. 4, on one of
the side plates engages. The number of teeth in this ratchet must be double that
of the toothed wheel L, in order to hold the tappet shaft in position after each
vibration of the driving lever, which is pivoted above its connection with the
armature, as shown in Fig. 2. The unison is effected by this tappet shaft k by
means of a third tappet f, adapted to act upon the end of an arm N pivoted to the
side plate, and constantly pulled upward by an adjustable spring g against an
adjustable set screw h, so that as the tappet shaft is revolved by the action of the
armature H and the retracting spring e, this tappet f is brought against the free
end of said pivoted arm N and is thereby arrested, and as that part of the battery
by which this is effected has not sufficient power to cause the tappet to pass said
arm, the initial point of all the instruments of the circuit is in this way effected.
In order to pass this point the entire tension of the battery S, R, Q, is brought
into use.
I have described the tappet 11 as operating the circuit closer 1, but it
will be understood that the position of this tappet can be adjusted on its shaft so
as to cause it to raise the circuit closer to suit the instruments at any station
corresponding with the number of the insulated discs. For example, this tappet
is shown as set for a particular station, say, number 5, but it may be adjusted for
any other station. The bell and the electro magnet M² for ringing the same are
arranged and operated substantially as is ordinarily done. Referring to the
manner in which I effect and control the ground connections, it is important to
observe that the circuit closer 3 is brought into action to make the contact at a
certain time, that is, while the tension of the spring e is actuating the driving arm
and revolving the tappet shaft, and that at this time all the instruments are placed
in condition to enable them to make a ground connection by means of the switch
shown in Fig. 3 and 13. At the next attraction of the armature the tappet shaft
will be revolved and release the circuit closer 3, and thereby break the ground
connections at the stations and put the line in a normal or perfect working
condition. Should any of the switches of the stations be left on all the instruments
can be brought to a point where the line may be used for telephoning without the
use of the ground wires. I mean by this, that the line wire F is brought to a
perfect working condition by bringing the revolving arm D in contact with the

page_text: dise e³, and that this has the effect of putting on the working battery Q, R, and
thereby moves the tappet shaft k forward and releases the circuit closer 3, and
thus disconnects the ground wire 10, Figure 13, from each of the circuit instruments
as already described.
"
To use the telephone at any station the switch lever is shifted to the right or to
the left, as shown by dotted lines in Fig. 3, to raise the circuit closer J2, Figs. 3
and 13, which cuts in the telephone, and puts on the ground wire, and the
communication is made the same in either direction, the telephones being shown in
their proper connection with the instrument by the binding posts 16 and 17, and
their proper wires, as shown in Figs. 1 and 13. I have stated that a single battery
having different degrees of tension or power is used in connection with my
transmitter and call apparatus, and, as shown in Figs. 1 and 13, the several degrees
of tension are designated by the letters Q, R, S, with which the transmitter wires
are separately connected, and in which the section marked Q has the least tension;
the section R includes the tension of Q, and S includes the whole force, and thus
lessens the expense of obtaining power, and while I prefer this construction, yet I
do not wish to confine myself to such form, but may use three separate batteries.
There is arranged upon the side of each station instrument in close proximity to
the electro magnet Ma magneto-indicator," as shown by dotted lines in Fig. 2,
under the influence of the electric current passing through the electro magnet M,
which indicates whether the line is in use. It will be understood that when the
line is used for telephoning, the battery at the main station is disconnected, the
needle T will then point to O, showing that the line is in use; but when the battery
is connected to the line, the needle will be deflected from O, which indicates that
the line is not in use. This indicator is shown in Fig. 2ª, Sheet 1; in operating
from the central station to call, say, No. 5, the operator presses on the push
button, which will be numbered B³, Fig. 1. This puts on the whole battery.
The arm D is then released by pressing on the button E, or revolved by hand,
causing it to pass over the insulated discs c, and thereby opens and closes the line
or circuit, and in passing B5 causes the bell to be rung at that station. This being
done the arm D is carried to the insulated disc c¹, to receive the reply from the
local station, after which the arm D is again carried round to the insulated point
shown by dotted lines in Fig. 1, to place all the instruments in condition to use the
ground wire. The movement of the arm D is effected by clock work connected
with its post C, said arm being controlled in its movements by the push button E,
Fig. 11, but such clock connection may not be used, as it is obvious that said arm
may be moved as required by hand, to use the ground wire as described, and for
all the purposes for which it is intended. The telephone is then switched in at the
main and circuit stations and the two can communicate by telephone. After this is
through, the line is again switched to the transmitter, and the arm D carried to the
dise c, and in doing so, disconnects the ground wires of the circuit stations, leaving
the line in its normal condition. This disconnection of the ground wire is made by
bringing the arm D in contact with the disc c³, Fig. 1, which, as before stated,
connects the working battery Q, R, with the line, thereby moving the tappet shafts
of all the station instruments forward one tooth, and thereby releasing the circuit
closer 3, and breaking the ground connection. In making a revolution over the
insulated discs, the arm D, in passing from one insulated point c to the others,
opens and closes the circuit as stated, and by so doing operates the mechanisms
of the circuit stations, and thereby cuts out the push button at each of these
stations, and thereby prevents all interference with the line, thus giving complete
control of the whole system to the operator at the main station. In this operation
of the revolving arm D all the push buttons I of the circuit stations are shunted out
after the arm D is moved beyond its normal point, which is the disc c', and which
connects the small battery Q, to allow all the outlying stations to call or signal the
.main office without disturbing the mechanisms of any of such stations, as before
stated. In Fig. 13, I have represented the relative electrical relation of the disc c¹
with the segment 6³, and the binding post G', by the wire b, by which the smallest

page_text: battery is brought in connection with the main line F, for the purpose of
allowing any of the circuit stations to call the main station without disturbing
the mechanism of any of the circuit stations; and this battery is used singly
exclusively for this purpose; and the position of the arm D in said Figure indicates
the point at which such battery connection is made with the main line, and at
which any of the stations can call in. The battery wires and the line wire F are.
shown in their proper relation and connection with the disc c¹, and the rotating
arm by the wire 6º connecting the shaft of said arm with the binding post G. In
Fig. 14 the disc c² is shown in connection with the arm D, the segments b₁, 67,
and 6; the spring a³ and the binding post G³ by the wires 68, by which the full
battery Q, R, S, is brought in connection with the main line F, which is in
connection with the arm D by the wire bº. In this relation of the arm the tappet
shafts of the circuit station instruments are passed beyond the unison point by
the force of the full battery, leaving all of said instruments in condition to be
brought again to a unison point by the working battery Q, R, by rotating the
arm D over the discs c, as before stated.
In the relation of the parts shown in Fig. 14, the transmitter has another
function, but in connection with the working battery Q, R, as shown in Fig. 15,
in which it will be seen the said arm D is in connection with the binding post G³
by the wire 6, the segments b², 62, and 610, and the springs a, a³, the said arm
being in connection with the main line F by the wire 6º, so that by depressing
the button B2 the said springs will be joined, thereby disconnecting the full
battery Q, R, S, as used in Fig. 14, and connecting the working battery Q, R, with
the line for preventing the tappet shafts of the instruments that are in unison from
passing such point while rotating the arm D over the disc c, for bringing those
instruments that may be out of unison up to the unison point. The push button B²
is operated, as stated, only when it is thought any of the instruments are out of
unison. It will be understood that all the discs c, and including the discs c³ and c¹,
are used for propelling the tappet shafts by the working battery Q, R, with which
they are connected by rotating the arm D passing over them, as before stated, the
designation of the discs c³ and c being made merely to indicate the position of
the arm D between such discs, as shown by dotted lines in Fig. 1, when all the
ground connections are made at the circuit stations. In Fig. 16 the arm D is
shown in connection with one of the discs c and the working battery Q, R, by the
segment b, spring a', segment b², wire 6, and the binding post G2, and this connec-
tion is to show that said arm may be connected with such battery by any one of
the discs except the discs c¹ and c², for the purpose stated.
In this operation the push button B when depressed joins the springs a and a',
thereby disconnecting the working battery Q, R, and connecting the full battery
for the purpose of ringing the call without breaking the continuity of the line. In
both of these operations the arm D is in connection with the main line F by the
wire and the binding post G. All these operations are effected by rotating
the arm D and by the proper manipulations of the buttons B and B2, as set forth.
I have stated that the circuit closer 3 is lifted in the course of the back stroke of
the pendent propelling arm K, and is dropped by the forward stroke of the
armature. The lifting of the circuit closer 3 by the back stroke of the propelling
arm is for the purpose of bringing it in contact with the insulated spring 6 for
connecting the switch lever with the ground wire to make the ground connection,
and while there is no battery on the line, and the dropping of the circuit closer by
the forward movement of the propelling arm K takes place when the battery is
again applied for the purpose of disconnecting the switch from the ground wire,
and thus breaking the ground connection. This back movement of said arm K is
produced by the spring e, and this backward action of the arm K is essential to
complete the propelling movement of tappet shaft by rotating the ratchet wheel L
one half tooth, and thus give the tappet shaft a continuous rotation. The ground
connections are made at each and all the circuit stations at the same time, for the
purpose of allowing any one of the circuit stations to use the ground wire. This

page_text: •
is done when the battery is disconnected at the main office, and after all the bells
are shunted out, and by the back movement of the propelling arm K, bringing the
circuit closer 3 in contact with the insulated spring 6, as before stated. The
effecting of the unison of all the circuit station instruments is done by the operator
depressing the push button B2, which disconnects the whole battery and connects
its sections R and Q, after which the arm D is caused to revolve, and in passing
over in contact with the discs the several instruments are thereby brought to an
initial point, but cannot pass it until the arm is again brought in contact with
disc c² after the button B2 is released. It is obvious that the number of teeth in
the wheel L and the push buttons of the transmitter must correspond to the
number of stations; but the wheel L must also have two additional teeth to
correspond with the movement of the arm D from its insulated point, shown by
dotted lines in Fig. 1, to the normal point, and from there to pass the unison
point c, the movement given the wheel by these additional teeth being equal to
the movement of the arm between the points stated. The circuit calling apparatus
is enclosed in a case or cover, the bell and the magneto-indicator only being
exposed.
Having now described my Invention, and the manner in which the same may be
carried into practical effect, I would have it understood that I do not desire to
limit myself to the exact details as shown and described, as they may be varied
without departing from the peculiar nature of this my said Invention, but what I
do claim and desire to secure by Letters Patent is,―
1st. The combination with a telephone or telegraph line of a call apparatus
located at the circuit station, and having the pivoted circuit closer 1, its insulated
contact point 4 operated by mechanism consisting of the tappet shaft k, 11, the
driving lever K, l, engaging with the toothed wheel L on said tappet shaft, the
retracting spring e connected with said lever, the magnet M, its armature H, and
the transmitter A, and battery sections Q and R located at the main station, whereby
the bell is shunted out and cut in the main line at all the stations solely by said
transmitter and the battery sections, all constructed for co-operation substantially
as herein set forth.
2. The combination with a telephone or telegraph line, the battery, and
transmitter located at the main station, of a call apparatus located at the circuit
station and having a single circuit closer 2, a single fixed insulated contact
point 5 for said circuit closer, the shaft k. with the tappet 12 for operating the
same, the magnet M and the armature H, the circuit closer and its insulated
contact point being connected by the wires 14 and 8 and arranged to form a shunt
around the push button I and the telephone, the said tappet shaft being operated
by mechanism, constructed substantially as described, whereby the telephone
and the push button of the instruments at each station on the line are shunted out
simultaneously, thereby preventing any interference to the proper operation of the
circuit instruments by opening any one of the said push buttons or interposing
the resistance of any one of the said telephones during the operation of calling a
station.
3. The combination with a telephone or telegraph line of a call apparatus
located at the circuit station, and having the circuit closer 3, its insulated contact
spring C, and operated by mechanism substantially such as described, and the
transmitter A, and the battery sections Q and R located at the main station,
whereby the connections between the ground switch lever J and the ground
wire 10 are placed beyond the control of the circuit stations and under the control
of the operator at the main station, all constructed for co-opreation, substantially as
herein set forth.
4th. The combination with a telephone or telegraph line of a call apparatus
having a unison mechanism, consisting of the tappet shaft k, f, the pivoted arm N,
the adjustable spring g, the set screw h, the driving lever K, operating said tappet
shaft by the magnet M, its armature H, and retracting spring e, and the
transmitter and batteries located at the main station, whereby all the circuit

page_text: instruments that may be out of unison are adjusted to an initial point by the
operator at the main station, substantially as herein set forth.
5. The combination with a telephone or telegraph line of a call apparatus
located at the circuit station, and provided with mechanism for shunting out and
cutting in the bell in the main line through the circuit closer 1 and the contact
point 4, of mechanism for shunting out and cutting in the push button I through the
circuit closer 2 and-the contact point 5, of mechanism for breaking and making the
ground wire 10 through the circuit closer 3 and insulated contact spring 6, and of
mechanism for effecting the unison of all the circuit station instruments, all being
under the control of the transmitter and batteries at the main station, substantially
as and for the purpose herein set forth.
6. The combination with a telephone or telegraph line and a call apparatus
located at the circuit station, and constructed substantially as herein set forth, of a
transmitter located at the main station and having a series of push buttons B,
the contact springs a, a¹, upon which they act, a series of insulated discs c,
an arm D revolved over and in contact with said discs, and the metallic
segments b, 61, 62, 63, b', for connecting such discs with the batteries, substantially
as herein described.
7th. The combination with a telephone or telegraph line and a call apparatus
located at the circuit station of a transmitter provided with the revoluble arm D,
the insulated disc c², the push button B², its contact springs a, a³, and the
segments b, b', b7, and the batteries connected with said springs; said push
button when at rest leaves the spring a³ in contact with the segment b², bringing
in operation the larger battery for the purpose of passing the shafts of all the
instruments beyond the unison stop, and when said button is depressed to connect
said springs it disconnects the whole battery, and connects the two sections of the
battery Q and R for the purpose of preventing the tappet shafts from passing the
unison point while the arm D is making one revolution, substantially as herein
set forth.
8. The combination with the call apparatus at the circuit station, constructed
substantially as herein set forth, of a transmitter having a series of push buttons B
corresponding to the numbers of the circuit stations, their spring contact points
a, a', the insulated discs corresponding thereto, and the revoluble arm D operating
in connection therewith, as described, of the combined battery Q, R, S, whereby the
depression of any one of said buttons connects said combined batteries with the
line and rings the call or gives the signal to the circuit station designated by said
button.
9. The combination with a telephone or telegraph line, a call apparatus located
at the circuit stations, and a transmitter located at the main station, and having a
revoluble arm E, a series of concentric insulated discs over and in contact with
which said arm revolves, and a series of corresponding concentric push buttons B
arranged on the top of said transmitter, substantially as described, of metallic
segments and contact springs arranged on the underside of said transmitter, and
connecting said discs with the battery, while said arm connects said dises with the
line, substantially as and for the purpose herein set forth.
10. The combination with a telephone or telegraph line, a transmitter, and a
battery located at the central station, of a series of pivoted circuit closers 1, 2, and 3,
their insulated contact points 4, 5, and 6, and mechanism for operating said circuit
closers located in the call apparatus, the said mechanism being solely operated and
controlled by the battery and transmitter at the main station, substantially as and
for the purpose herein set forth.
11. The combination with a telephone or telegraph line, a transmitter, and a
battery at the main station, constructed substantially as herein set forth, of a series
of pivoted circuit closers 1, 2, and 3, operated respectively by the tappets 11 and
12 on the shaft k and the unison device, consisting of the pivoted arm N, operated
by the tappet f on said shaft and controlled by the spring g and set screw h, and
the propelling lever K for operating said tappet shaft, all located in the call
•

page_text: apparatus, and operated and controlled by said transmitter and battery, substantially
as and for the purposes herein set forth.
12. The combination with the circuit closers 1, 2, and 3, their insulated contact
points 4, 5, and 6, of the shaft k, provided with the tappets 11 and 12 for operating
said circuit closers, and the toothed wheel L operated by the driving lever K, L,
which is itself operated by the armature H and the magnet M, and the retracting
spring e, all constructed for co-operation, substantially as herein set forth.
13. The combination with the tappet shaft k, its toothed wheel L, the circuit
closers, the unison pivoted arm N, and the driving mechanism for said tappet shaft,
consisting of the lever K, magnet, armature, and spring e, constructed for operation
substantially as set forth, of the check ratchet wheel m on said tappet shaft and
the pawl n, said ratchet wheel having double the number of teeth than the driving
wheel L, whereby the tappet shaft is held in position after being driven a half
tooth at each vibration of the driving lever, such half tooth movement being
necessary to release the circuit closers for shunting out the bells and making the
ground connection while the battery at the main station is disconnected,
substantially as described.
In witness whereof, I, the said Anthony Michael Frankenberg, have hereunto
set my hand and seal; this Twenty eighth day of March, in the year of
our Lord One thousand eight hundred and eighty one.
ANTHONY MICHAEL FRANKENBERG. (L.S.)