Improvements in Telephonic Apparatus.
Year: 1896

page_text: Date of Application, 25th Aug., 1896-Accepted, 6th Mar., 1897
Improvements in Telephonic Apparatus.
I, CARL JOSEPH SOHWARZE, of 45 Church Street, in the City of Adrian, State
of Michigan, United States of America, Manufacturer, do hereby declare the
nature of this invention, and in what manner the same is to be performed, to be
particularly desoribed and ascertained in and by the following statement :-
My invention relates to a telephonic apparatus comprising speaking and signalling
instrumentalitics organically combined, and it is the object of my invention to
simplify the construction and improve the oporation of the instrument, and further
to adapt it to be used under different conditions or in connection with different
exchanges or systems.
In the drawings,
Fig. 1 is a side elevation of my device showing the casing in section.
Fig. 2 is a horizontal section on line Fig. 1.
Fig. 3 is an elevation of the switch operating and resetting lever.
Fig. 4 is a section ou line y y Fig. 3.
Fig. 5 is a diagram showing the arrangement of the circuits and
Fig. 6 is a diagram showing a modified construction of my instrument.
In its simplest form my invention comprises an electric generator for producing
the signal current and a microphone transmitter so combined that the generator
forms the transformer or induction coil for the trausmitter, and further that the
microphonic material of the transmitter will be agitated by the operation of
sending the signal.
In Fig. 6 I have shown diagrammatically a construction in which tho signal
generator comprises a battery 1, an induction coil or transformer, consisting of the
primary coil 2, the secondary coil 2" and the magnetic core 2, and a commutator 3
for reversing the direction of the battery current in the primary coil, to induce an
alternating signal current in the secondary coil.
The
The microphone comprises the diaphragms 4 and 5 with the microphonic
material 6 (preferably granular carbon) between the diaphragm 4 being formed of
magnetic material and arranged in proximity to the magnetic core 2.
secondary coil 2ª is connected into the line circuit and the microphone is included
in a local circuit with the battery and primary coil. Another diaphragm 7 is also
preferably arranged in proximity to the opposite end of the core 2.
With an instrument so constructed when used for signalling, which is accomplished
by revolving the commutator 3, the diaphragm 4 will bo violently vibrated by the
magnetic reversals in the core 2b, which will agitate the microphonic material 6,
thus keeping the transmitter always in good condition.
In the construction shown in the other figures of the drawings, a magneto electric
signal generator is employed, which I shall now describe in detail.
A is a suitable box or casing. Within this casing is arranged the field magnet
of the magneto electric generator, preferably comprising the oppositely arranged
horse shoe magnets B and B', having their like poles united by the rings or unnular
pole pieces Caud C. D is a pole armature arranged to revolve between the
segmental pole pieces E and E on the magnets B, B and journaled in suitable
non-magueto heads F. This armature has a double winding consisting of the
primary coil D' and the secondary coil D', one terminal of each coil being connected.

page_text: to the metallic core of the armature, the other terminal being connected
respectively to the insulated posts D D', which are connected to the insulated
pins DD, passing out from the opposite ends of the armature shaft.
G is a sprocket wheel on one end of the armature shaft connected by a chain G
to the sprocket wheel H on the crank shaft HI'. This shaft is preferably journaled
in bearings formed in the magnet B and extends out through an aperture in tho
casing, being provided with a suitable crank handle (not shown) for actuating it.
I is a head or disk at the opposite end of the armature ehaft. I are pins
projecting from the outer face of the disk at diametrically opposite points. Jis a
lever, which is shown in the form of a bell crank, fulcrumed upon the post J
secured to the magnet B. The free end of this lever is adapted to move into the
path of the pins 11 and is provided with the oppositely inclined cam faces JJ
adapted to. bear against said pins and turn the armature into the position shown in
Figs. 1 to 4 of the drawing, i.e. with its poles extending at right angles to the
longitudinal axis of the magnets.
Jis a spring tending to move the lever J against the pins 1. Jis the actuating
arm of tho lever projecting out through an aperturo in the casing and provided
with the hook J' on which the ear phone is hung, and the knob or finger key J.
J is a spring beneath the arm J', upon which said arm normally rests, the
weight of the ear phone being sufficient to overcome the tension of the spring J.
K is a spring plate secured to the lover J but insulated therefrom and adapted to
contact with the pin D' in the end of the armaturo shaft, when the lever J is in its
uppor position.
Land M are contact springs adapted to contact with the lever J. in different
positions of that lever.
N and Naro irou diaphragms seated upon the annular pole pieces C and C' and
forming portions of the opposite poles of the magnet, the diaphragm N' constituting
the receiving diaphragm of the telephone.
O and O are caps for securing the diaphragms to the annular pole picces. Pis
a flexible tube through which the sound is conveyed from the receiving diaphragm N'
to the ear phone P
R is a diaphragm, preferably of carbon, arranged in front of the diaphragm N
and separated therefrom. S is a ring of folt or other soft material placed between
the two diaphragms N and R and filled with granular carbon or like microphonic
material S¹.
N' is a roughened carbon plate attached to the diaphragm N against which the
granular carbon is placed. T is a metallic ring sccured to the cap O by screws T
and firmly clamping the carbon disk R in position. To this ring the mouth
piece Qis secured and a screen T" is preferably placed across the inner end of this
mouth piece to protect the carbon disk from injury.
The caps OO may be secured in any suitable manner to the annular pole
pieces preferably as shown in the drawings by a scrow threaded engagement.
The arrangement of the electric connections is shown in Fig. 5 of the drawings,
in which 8 and 8" are two binding posts to which the main line wire and return or
ground wire are respectively attached. 9 is a connection between the post 8ª
and a contact spring U bearing against the pin D in the end of the armature
shaft.
10 is a connection between the post 8 and the metallic frame of the instrument,
in which connection the bell V is included. 11 is a connection between the post 8*
and the spring contact L and 12 is a connection between the post 8 and the contact
spring M.
13 is a connection between the contact spring K and the metallic ring T, which
connection so includes the local battery W.
In the normal position of parts, where the telephone is not in use, the lover J is
held in its mid position, as indicated by full lines in Fig. 3, by the weight of the our
phone, which overcomes the tension of the spring J and holds the lever against
the spring J. In this position the spring K has broken contact with the pin D',

page_text: the spring M has broken contact and the spring L has made contact with the
lever J,
which completes the circuit from the post 8 through the connection 10 and
bell to the metallic. frame of the generator, and through said frame to the
lever J (as iudicated by the connection 14 in the diagram) and thence through the
spring and connection 11 to the post 8.
The bell may now be rung when desired by the operator at the other end of
the line, the signal current passing over the line and through the connections just
described to the ground or return. In responding to the call the user lifts the car
phone from its hook which allows the lever J to be drawn by the spring J' into
the position where the apring K, contacts with the pin D', the spring L has broken
contact with the lever J and tho spring.M has made contact therewith as indicated
by dotted lines at Jo (Fig. 3).
This breaks the bell oircuit before described and closes a circuit from the
post 8 through the connection 9 and spring U to the pin D, thence through the
coil D' to the armature core and through the metallic frame to the lever J, thence
through the contact spring M and connection 12 to the post 8. The local battery
circuit is also completed from the battery W through the connection 13 to the
spring K and through the pin D and primary coil D to the core of the armature,
thenco through the metallic frame to the diaphragm N and through tho granular
carbon to the carbon diaphragm R, whence it passes through the ring T and
connection 13 to the other pole of the battery.
The telephone is now in condition to be used as a speaking instrument, the
armature D with its coils D1 and D' forming the induction coil or transformer for
the microphone transmitter, and also in connection with the diaphragm N' forming
the receiver.
To operate the signal generator the operator presses upon the knob J', depresses
the lever J by compressing the spring J to a position lower than its normal
position, or as indicated in dotted lines at J, Fig. 3. This breaks the contacts of
all three springs K, L and M, opening the local battery circuit and the two
shunts 11 and 12, the only remaining circuit being from the post 8 through the
connection 9, spring U, pin D', coil D', the metallic frame connection 10 and
bell V to the post 8. The armature may now be revolved which generates a
current in the coil bringing the bell V and passing over the other end of the line
ringing the bell of that instrument. At the same time the revolution of the
armature will cause a violent vibration of the diaphragm N as each of the poles
passes it, which agitates the granular carbon.
Upon releasing the pressure on the knob J', the lever J is moved by the
springs J and J and the cams J' and J, striking against the pins I turn
the armature into its normal position and lock it there while the telephone is
being used.
It will be observed that with this construction of instrument, by removing the
carbon diaphragm R and the microphonic material, there remains a complete
imagneto telephone, the diaphragm N forming the transmitter and the diaphragm N'
the receiver. Thus the instrument is especially adapted to be used in connection
with exchanges where both magneto and microphonic transmitters are employed,
as the operator may at any time quickly convert it from the one to the other form
of instrument as occasion requires.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. A telephone comprising a microphone transmitter arranged in magnetic
inductive relation to a magneto-electric signal current generator and adapted to
have its microphonic material agitated during the operation of the generator by the
magnetic disturbance caused thereby.
2. A magneto telephone having a microphone transmitter in mechanical contact
with its vibratory diaphragm, said telephone also constituting a signal current

page_text: generator adapted in its operation to agitate the microphonic material by the
magnetic disturbanco caused by euch operation..
3. The construction of switch hook and arrangement of electric circuits sub-
stantially as described.
Dated 30th dox of Tulo 1806
HASELTINE, LAKE & Co.,
45 Southampton Buildings, Loudon, W.C., Agents for the Applicant.