IMPROVEMENTS IN TELEPHONIC APPARATUS.
Year: 1880

page_text: LETTERS PATENT to Henry Harris Lake, of the Firm of Haseltine, Lake,
"
& Co., Patent Agents, Southampton Buildings, London, for an Invention of
"IMPROVEMENTS IN TELEPHONIC APPARATUS.' A communication from abroad
by George Lee Anders, of Boston, and Thomas Augustus Watson, of Everett,
both in Massachusetts, United States of America.
PROVISIONAL SPECIFICATION left by the said Henry Harris Lake at the
"
Office of the Commissioners of Patents on the 3rd February 1880.
HENRY HARRIS LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN TELEPHONIC APPARATUS.
[A communication from abroad by George Lee Anders, of Boston, and Thomas
Augustus Watson, of Everett, both in Massachusetts, United States of America.]
According to this Invention there is provided at each station a switch per-
manently connected to the line, which switch can be moved so as to connect the
line to earth at each station, or to disconnect the line from earth; an electro-
magnet operated by the main line current, and moving the switch by the return
movement of its neutral armature when the current through said electro magnet
is broken; a polarized armature affected by the main line current, and arranged so
as to determine the movement of the switch in one or the other direction, according
to the polarity of the current, by the interruption of which the movement of the
switch is effected by signalling apparatus operated by alternate positive and
negative currents of such force or duration as not to attract the neutral armature;
and a locking device, which prevents the signalling apparatus at any station from
being operated except when the line is grounded at that station.
The result accomplished by this combination is that any number of these
apparatus may be placed on a line, and that the signalling apparatus at any station
can be operated at will without operating the signalling apparatus at any of the
other stations.
In carrying the said Invention into practice I provide an electro-magnet attached
to a plate, which supports the call bells. I also provide a permanent magnet
attached to the said plate, and having one extremity bent at right angles, so as to
extend over and magnetize an armature which is pivoted above the poles of the
[Prin d

page_text: electro-magnet upon a lever, which is pivoted on the aforesaid plate. Upon each
of the poles of the electro magnet there are extension pieces of soft iron at right
angles to the axis of the magnet. I further provide a neutral armature of soft
iron, which is attracted by these extension pieces, and is attached to the said
pivotted lever. Both the neutral armature and polarized armature therefore move
with this lever, but the polarized armature oscillates on the same. The bell-
hammer of the call-bells is attached to this polarized armature, and is vibrated by
its oscillations. A retracting spring is attached to the pivotted lever, or the
instrument may be so placed that the armature will fall back from the poles of
the magnet by its weight when the current is broken. Attached to a standard on
the aforesaid plate there is a metal plate and a block of some suitable insulating
substance. Below another armature and pivoted on the last named plate there is
a metallic switch-lever having two arms, one on each side, and at right angles to
the lever, which arms extend over the polarized armature when the neutral
armature is retracted, but when the neutral armature is attracted the polarized
armature in its oscillations clears the ends of the arms. In the said block is placed
a plate of metal, which is connected to the earth, with which plate the last-named
lever which is connected to the line is made to make and break contact as it may
be desired to connect the line to earth at the station or to establish a circuit
through the station.
Upon one of the arms is a projection extending downward, and upon the other
arm is another projection, which differs from the first named projection by being
bevelled off on its under side.
When the switch-lever is in the position in which it is disconnected from the
ground-contact, and its extremity rests upon the insulating block, so that the line
circuit is completed through the stations, the first named arm will be in such a
position that if the end of the polarized armature opposite said arm is attracted it
will pass under said arm when the neutral armature makes its back stroke, but if
the polarity of the current in the electro-magnet is reversed, so that the end of the
polarized armature opposite the said arm is repelled, and the end of the polarized
armature opposite the second arm is attracted, the projection on the arm will be
struck by the armature when the neutral armature makes its back stroke, and will
move the end of the switch lever into contact with the metallic piece in contact
with the earth. The switch-lever can be restored to its original position by
changing the polarity of the current in the electro-magnet and then breaking the
current, when on the back stroke of the neutral armature the projection on the
second arm will be struck by a projection on the polarized armature. When
the armatures are in a certain position the polarized armature is under the pro-
jection on the first arm, and consequently the polarized armature is prevented
from oscillating, but when the armatures are in another position the polarized
armature is not prevented from being oscillated, for the reason that the projection
on the second arm and the projection on the polarized armature are bevelled off, so
that room is afforded for the oscillation of the polarized armature.
I do not confine myself to the particular form of apparatus described, as this
can be modified in many ways without departing from the principles of the said
Invention.
In the operation of this Invention a series of these instruments are arranged on
the line, one at each station, and the switch-lever on each instrument is in such a
position that the earth connection at each instrument is broken. The current is
then put on the line, when the neutral armatures will be attracted and the polarized
armatures unlocked. The current is then reversed, so as to put the polarized
armature into the position in which it is free to oscillate, and then on breaking
the circuit the neutral armature will be retracted and the polarized armature will
strike the first arm and cause the metallic piece to move into contact with the
plate in the block, and thus establish an earth connection at each station. When 5
the line is in this condition, should it be desired to ring the signal bell at any
station, say at station No. 3, a current in the reverse direction is closed and broken

page_text: as many times as there are stations on the line between the central office and the
station that it is desired to call. The first making and breaking of the current has
the effect to remove the switch-lever from the earth contact at station No. 1; the
second making and breaking of the current produces the same effect at station
No. 2, and so on for each succeeding station. The earth-contact at the station
which it is desired to call is not removed, and consequently for the reason that the
polarized armatures at the succeeding stations are locked, as before explained,
while the polarized armatures at the other stations are in one position, and free to
oscillate. The bell at the station which it is desired to call can be rung from the
central office by vibrating the polarized armature by alternate positive and negative
currents of less force or duration than required to affect the neutral armatures, and
as the current goes to earth at that station the armatures of the instruments at
the stations beyond will not be affected. After the station is called the switch-
levers at the preceding stations are put on their respective earth contacts by the
operation before explained.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Henry Harris Lake in the Great Seal Patent Office on the 3rd
August 1880.
HENRY HARRIS LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN TELEPHONIC APPARATUS."
A communication from abroad by George Lee Anders, of Boston, and Thomas
Augustus Watson, of Everett, both in Massachusetts, United States of America.
.
According to this Invention there is provided at each station a switch per-
manently connected to the line, which switch can be moved so as to connect the
line to earth at each station, or to disconnect the line from earth; an electro-
magnet operated by the main line current, and moving the switch by the return
movement of its neutral armature when the current through said electro-magnet is
broken; a polarized armature affected by the main line current and arranged so as
to determine the movement of the switch in one or the other direction according
to the polarity of the current, by the interruption of which the movement of the
switch is effected by signalling apparatus operated by alternate positive and
negative currents of such force or duration as not to attract the neutral armature ;
and a locking device which prevents the signalling apparatus at any station from
being operated except when the line is grounded at that station.
The result accomplished by this combination is that any number of these
apparatus may be placed on a line, and that the signalling apparatus at any
station can be operated at will without operating the signalling apparatus at any
of the other stations.
This Invention is illustrated in the accompanying Drawing, in which,-
Figure 1 is a perspective view from below of the said apparatus in its normal
position.
Figure 2 is a detached view of the switch.
Figure 3 is a detached view of the neutral and polarized armatures.
Figure 4 is an underside view of the apparatus shewing the switch disconnected
from the ground contact, and the polarized armature locked; and
Figures 4 and 4b are sections on the lines x, x, and x², x², Figure 4, of the
polarized armature and switch-lever when in the same position, as therein
shewn.
Figure 5 is an underside view of the apparatus shewing the switch connected
to the ground, and the polarized armature free to oscillate; and
Figures 5 and 5b are sections on the lines z, z, and x¹, z¹, Figure 5, of the
polarized armature and switch-lever when in the same position, as therein
shewn,
Figure 6 is a diagram shewing the switches at the several instruments on the
line all in connection with the ground; and
Figure 7 is a diagram shewing the ground connections open at two instruments,
and closed at the third and fourth.
Like letters indicate the same parts throughout the Drawing.
A represents an electro-magnet attached to the plate B which supports the call-
bells C, C, and D is a permanent magnet attached to the plate B, and having one
extremity bent at right angles so as to extend over and magnetize an armature E
which is pivoted above the poles of the electro-magnet A upon a lever F pivoted
on the plate B. In Figure 1 this bent extremity is broken away. Upon each of
the poles of the electro-magnet A are extension pieces G, G, of soft iron at right
angles to the axis of the magnet; H is a neutral armature of soft iron which is
attracted by these extension-pieces, and is attached to the lever F. Both the
neutral armature and polarized armature therefore move with the lever F, but

page_text: the polarized armature oscillates on the same. The bell-hammer M³ of the call-
bells is attached to this polarized armature, and is vibrated by its oscillations.
A retracting spring is attached to the lever F, or the instrument may be so placed
that the armature will fall back from the poles of the magnet by its own weight
when the current is broken. Attached to a standard on the plate B is a metal
plate I and a block K of some suitable insulating substance. Below the armature H,
and pivoted on this plate I, is a metallic lever L having two arms M, M', one on
each side and at right angles to the lever, which arms extend over the polarized
armature when the neutral armature is retracted; but when the neutral armature
is attracted the polarized armature in its oscillations clears the ends of the
arms M, M. In the block K is placed a plate of metal N which is connected
to the earth; with this plate the lever L, which is connected to the line, is caused
to make and break contact as it may be desired to connect the line to earth at the
station, or to establish a circuit through the station. Upon the arm M is a pro-
jection a extending downward, and upon the arm M¹ is a projection a¹ which
differs from the projection a by being bevelled off on its under side. When the
lever L is in the position shewn in Figure 4, and its extremity rests upon the
insulating block K, so that the line circuit is completed through the stations,
the arm M will be in such a position that if the end of the polarized armature
opposite the said arm is attracted it will pass over the said arm when the neutral
armature makes its back stroke; but if the polarity of the current in the electro-
magnet is reversed, so that the end of the polarized armature opposite the arm M
is repelled, and the end of the polarized armature opposite the arm M' is attracted,
as shewn in Figure 5, the projection a' on the arm will be struck by the armature
when the neutral armature makes its back stroke, and will move the end of the
lever L into contact with the metallic piece N in contact with the earth. The
arm L can be restored to its original position by changing the polarity of the
current in the electro-magnet A, and then breaking the current when on the back
stroke of the neutral armature the projection a' on the arm M¹ will be struck by
a projection b on the polarized armature. When the armatures are in the position
shewn in Figure 4, the polarized armature is under the projection a, as shewn in
Figure 4, and consequently the polarized armature is prevented from oscillating;
but when the armatures are in the position shewn in Figure 5, the polarized
armature is not prevented from being oscillated, for the reason that the pro-
jection a on the arm M', and the projection b on the polarized armature, are
bevelled off, as shewn in Figure 5b, so that room is afforded for the oscillation of
the polarized armature.
I do not confine myself to the particular form of apparatus described, as this can
be modified in many ways without departing from the principles of my Invention.
In the operation of the said apparatus a series of these instruments are arranged
on the line, one at each station, and the switch-lever L on each instrument is in
such a position that the earth-connection at each instrument is broken. The
current is then put on the line, when the neutral armatures will be attracted
and the polarized armatures unlocked. The current is then reversed so as to
put the polarized armature into the position shewn in Figure 5, and then on
breaking the circuit the neutral armature will be retracted and the polarized
armature will strike the arm M and cause the lever or arm L to move into
contact with the plate N, and thus establish an earth-connection at each
station, as shewn in Figure 6. When the line is in this condition should it
be desired to ring the signal-bell at any station, say, at station No. 3, a current
in the reverse direction is closed and broken as many times as there are stations
on the line between the central office and the station that it is desired to
call. The first making and breaking of the current has the effect to remove the
switch lever from the earth-contact at station No. 1; the second making and
breaking of the current produces the same effect at station No. 2, and so on for
each succeeding station. The earth-contact at the station which it is desired to
call is not removed, and consequently for the reason that the polarized armatures

page_text: at the succeeding stations are locked, as before-explained; and as shewn in Figure 4,
while the polarized armatures at the other stations are in the position shewn in
Figure 5 and free to oscillate. The bell at the station which it is desired to call
can be rung from the central office by vibrating the polarized armature by alternato
positive and negative currents of less force or duration than required to affect the
neutral armatures, and as the current goes to earth at that station the armatures
of the instruments at the stations beyond will not be affected. After the station
is called the switch-levers at the preceding stations are put on their respective
earth-contacts by the operation before explained.
Having thus fully described the said Invention as communicated to me by my
foreign correspondents, and the manner of performing the same I wish it understood
that I claim,―
First. In an electric circuit a series of switches permanently connected to the
main circuit, each of which switches is operated by an electro-magnet acting to
simultaneously put all the switches to earth or to consecutively remove the same
from earth, substantially as above set forth and for the purpose specified.
Second. In an electric circuit whose continuity is unbroken, a series of switches
permanently connected thereto, all of which switches are simultaneously put to
earth when their operating electro-magnets are discharged after a current in one
direction, and which are consecutively removed from earth by succeeding dis-
charges of currents in the opposite direction through their operating electro-
magnets, substantially as above set forth and for the purpose specified.
Third. The electro-magnet with its neutral and polarized armature in com-
bination with a grounding switch that is operated by the said magnet when the
same is discharged, substantially as above set forth and for the purpose specified.
Fourth. The combination with a polarized armature of a bell-hammer attached
thereto and vibrated thereby, of a switch for establishing a ground connection,
which switch when disconnected from earth locks the said armature and prevents
it from vibrating, substantially as above set forth and for the purpose specified.
Fifth. The combination with an electro-magnet of the pivoted lever F carrying
a neutral and a polarized armature of the said magnet and the pivoted lever L
which is moved to one side or the other by the back stroke of the neutral armature,
according as one pole or the other of the polarized armature is attracted to the
electro-magnet, substantially as above set forth and for the purpose specified.
Sixth. The combination with the switch lever L provided with the arms M, M¹
and the projections a, a, constructed as above described of the polarized armature
provided with the projection b, substantially as above set forth and for the
purpose specified.
In witness whereof, I, the said Henry Harris Lake, have hereunto set my
hand and seal, this Third day of August, in the year of our Lord One
thousand eight hundred and eighty