ELECTRIC TELEPHONEY
Year: 1885

page_text: "
WILLIAM BLENHEIM New Egham Surrey Telegraphic Engineer do hereby
declare the nature of my invention for ELECTRIC TELEPHONEY to be as follows:-
--
The receving portion consists of a U shape piece of iron rod with a coil of wire
wound on the center porton only. Over this and extending to the ends of the rod
is a seccondary coil of fine wire, the ends of the U are brought near an iron
armature fixed to the center of a membrane.
The transmitting portion consists of a piece of carbon or other meterial carried
by a yielding support to allow of a piston like motion, fixed near its edge is two
metal pins, these pins are conmected by a mital bar, supported at its center on a
knife edge end of a lever, which is weighted at the oposite end to put pressure on
the contact pins.
A Battery, the pins in Transmitter, and Primary Coil formes one Circuit, the
outer or seccondary Coil is connected to the line.

page_text: WILLIAM BLENHEIM Telegraph Engineer New Egham Surrey I do hereby
declare the nature of my invention for ELECTRIC TELEPHONEY is as follows and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
The
In the provisional specification No 8675 July 18th 1885 as mentioned a telephone
apparatus which consists of a Carbon Transmitter and a Magnetic Recever. I now
find that the Carbon Transmitter can with advantage be dispensed with.
Magnet Recever herein described answering the purpose of both Transmitter and
Reciver, when arranged and connected as shown in the accompanying drawings.
The same letter is imployed in each of the drawings as indicating the same
portion of the apparatus.
Fig. 1 is the Magnetic Recever which consists of an Iron Magnet or Magnets A
bent or arranged as shown, with one or more poles placed close to the Armature I
hereafter described.
The center porton of the Magnet A is surrounded by a primary coil of insulated
wire B. Over this primary coil is wound a seccondry coil of smaller wire which is
connected with and formes the Coils D, D, one the ends or poles of the Magnet or
Magnets A. The whole of the above is arranged on and supported by a metal
bar E. The distance between the poles of the Magnet A and the Armature I is
regulated by means of the nuts F F F F working on the screwd pillars P.
In Fig. 1 and 2 G G G consists of a ring of brass or other suitable meterial one
one side of which is fixed by any suitable means a Membrane or Tympan H of
non-inductive metirial. On the opposite side of the said ring is fixed a thin band
Armature I of-iron or steel about 4th inch wide and fixed by its ends accross the
diameter of the ring as shown in Fig. 2. The center of this Band Armature is
connected to the center only of the before mentioned Membrane or Tympan, by
means of a Sound Post K of sutiable meterial.
If now the poles of the Magnet or Magnets A are brought into close proximity
to any or several parts of the said Armature I (the proper adjustement being
obtained by means of the regulating Nuts F F F F on the pillas P) and a battery
is placed in circuit with the primary Coil B. The iron A is rendered magnetic
and a consequent attraction is set up between the electro magnet A and the Band
Armature I.
If now an undulating or Vibrating Electric Current from a Transmitter herein-
after described is caused to pass round the seccondry Coils C and D, D, the band
armature I is set in corrosponding vibration in consequence of the combined action
of the seccondry Electric Current acting on the several Magnetic Poles and thus
altering in unison their magnetic condition. This combined effect is conveyed by
means of the sound post й to the center only of the membrane or tympan, and
greatly increases the result as compaired with other methods.
When the above is used as a Transmitter it is arranged as shown in Fig. 3 the
Coils D D and the primary Coil B in this case are placed in circuit with the

page_text: battery. A closed curcuit is thus formed consisting of a battery, the Coils D, D,
and the primary Coil B.
The seccondary Coil C only is connected with the line wire and Receiver. The
seccondary Coil or Coils C and B may in this case if more convenient be detached
as shown in Fig. 3.
If now the membrane or tympan of the Transmitter be set in vibration by the
voice or other means the vibrations so set up are carried by the Sound Post K to
the Armature I the consiqient vibrations of which in front of the vairous poles of
the electro magnets or magnets vaires by inductive action the strength or tention
of the electric current passing round the several coiles, this in its turne produces
corrisponding changes in the magnetic condition of the Magnet A and induces a
seccondry current in the Coils C which being in connection with the line and the
receiving instrement reproduces similar vibrations in the membrane of the Recever
Fig. 1 as before discribed.
In Fig. 4 is shown a method by which a permanent Magnetic may be employed
to render A Magnetic in which case both the battery and the primary can be
dispinsed with. L repesents the permanent Steel Magnet, one pole of which is
connected to the back or center of the Electro Magnet A the other pole N is placed
between the membrane H and Armature I and in close proxminity to the sound
post K which in this case is preferable made of iron or steel and magnitised by
induction of the near pole of the permanant Magnet L. This arrangement as
show serve both as Transmitter and Receiver.
The other portons is similar to those already discribed and shown in Figs. 1-2
and 3.
Having now particularly discribed the nature of my said Invention and in
what manner the same is to be performed I declare that what I clam is
First. The use of a Band Armature in combination with a Sound Post of
magnetic or nonmagnetic meterial as shown and described.
Seccond. The use of a Magnetic Transmitter as discribed and shown in Fig. 2 in
curcuit with a battery and primary wire of an induction coil.
Third. The use of a Permanent Magnetic in combination with the said Band
Armature and Sound Post as described and shown in Fig. 4.
Dated this 15th day of February 188s
WILLIAM BLENHEIM,
New Egham, Surrey.