Improvements in and connected with Telephones.
Year: 1892

page_text: Date of Application, 27th Jan., 1892
Complete Specification Left, 27th Oct., 1892-Accepted, 3rd Dec., 1892
PROVISIONAL SPECIFICATION.
Improvements in and connected with Telephones.
We, GEORGE LEE ANDERS of 33 Peak Hill Gardens, Sydenham, in the
County of Kent, Electrician, and WALTHER KÖTTGEN of 10 Jeffrey's Square, in
the City of London, Merchant, do hereby declare the nature of this invention to
be as follows:-
This invention relates to telephonic apparatus and connections as hereinafter
more fully indicated.
The transmitter has preferably a cylindrical base provided with a recess in which
is placed a microphone enclosed by a diaphragın surmounted and held in place by
an annular ring which serves the double purpose of a mouth piece and a receptacle
for the receiver. The terminals for the line, battery, earth and bell are suitably
attached to the transmitter base, while conducting cords from the battery and line
terminals on the microphone connect the transmitter with the receiver. By the
use of a direct current in the transmitter the use of an induction coil, local battery,
and circuit is rendered unnecessary.
The carbon for varying the resistance is preferably formed from carbonized fibre
such as cotton, which before or after carbonization may be impregnated with fine
carbon or plumbago.
It is usual in telephone receivers to enclose the magnet and coil in a cylindrical
case by a diaphragm clamped to the case by a screwed mouthpiece" according
to this invention it is proposed to reverse this arrangement by forming the mouth-
piece for listening and the case in one piece, and at the back of the case forming
a screw thread and fitting thereon a screwed collar, said collar clamping all the
parts firmly. The construction and arrangement being as follows:-First the
diaphragm is placed in the case, this rests upon a shoulder forming the air space;
upon this diaphragm rests a short piece of tube or band which carries a spring
pressing upon a ball, the ball resting in an opening in the case through which it
projects. On the top of the tube or band is placed the back which is preferably
in the form of a rosette, having a press button in the centre, this button communi-
cates with a ringing key on the inner face of the rosette, on this face is also
mounted the magnet and coil, the length of the magnet from the face of the rosette
is sufficiently less than the depth of the ring or band to form the adjustment
distance between the pole of the magnet and the diaphragm. The rosette with the
magnet and ringing key is inserted into the case, and the screwed collar screwed
on, thus securing the whole firmly together in adjustment, and rendering unnecessary
the usual delicate adjusting rings of metal or paper.
When the receiver is pushed into the annular ring or mouthpiece on the trans-
mitter, the metal ball projecting from the side of the receiver case is forced inwards,
and with it the spring switch, this opens the circuit to the coil and microphone, and
establishes a circuit from the line terminal through the conducting cord to the
ringing key, spring switch, metal ball, annular ring on transmitter and thence to
bell, so that if a current arrives from a distant point the bell will ring. If while
the receiver is held in its place on the transmitter the ringing key on receiver be
pressed, a current will pass from the battery to key, flexible cord to line, ringing
the bell at the distant station. Again if the telephone receiver be pulled out of
the transmitter and put to the ear and the transmitter be spoken to, the articulating
current will pass from battery through the microphone, flexible cord, coil in
receiver, spring switch, key, and flexible cord to line. In this case when the
receiver is removed from the transmitter the ball breaks connection with the annulai
flange on the transmitter and makes connection with the coil, microphone and

page_text: battery, being pressed outward by the spring until the switch comes in contact with
the end of the coil, putting the telephone in circuit with a distant point.
It follows from the construction above indicated that the entire telephonic
apparatus may be formed so as to resemble in appearance an ordinary push button,
and its simplicity of construction and use will render it particularly applicable for
private residences, hotels, and the like.
Dated this 27th day of January 1892.
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London, Agent for the Applicants.
COMPLETE SPECIFICATION.
Improvements in and connected with Telephones.
We, GEORGE LEE ANDERS, of 33 Peak Hill Gardens, Sydenhamn in the County
of Kent, Electrician, and WALTHER KÖTTGEN of 10 Jeffrys Square in the City
of London, Merchant, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :—
This invention relates to certain improvements in and connected with telephones
the improvements being described in connection with a combined telephone trans-
mitter, receiver, and signalling device or bell push such an instrument being
adapted for domestic uses as in private residences hotels and the like as well as for
public or more extended purposes.
To clearly explain our improvements one form of instrument in which the same
are contained or comprised is illustrated in the accompanying drawings in which
Fig. 1 is a side sectional elevation of the combined transmitter receiver and bell
push.
Fig. 2 is a front elevation of the transmitter alone the receiver and bell push
being removed therefrom.
Fig. 3 is a back view of the transmitter.
Fig. 4 is a side elevation of the apparatus with the receiver removed as it would
be when the instrument is being used.
Fig. 5 is a section taken on line - looking in the direction of the arrow Fig. 1.
Fig. 6 is a similar view with the receiver removed from the transmitter mouth-
piece and shewing the parts in another position.
Fig. 7 is a front view of the push button looking in the direction of the arrow
Fig. 3 the outer cap or rosette being removed.
Fig. 8 is a view of a portion of the case of the receiver shewing the means of
securing the diaphragm.
Fig. 9 is a diagram illustrating the path of the currents when the receiver is in
position and the apparatus is ready to signal or to receive a signal and
Fig. 10 is a similar view illustrating the path of the currents when the receiver
is out and the apparatus is ready to be spoken into and to receive messages.
The transmitting portion of the instrument consists of a base 1 of insulating
material in a central hole of which is held a block 2 of hard carbon such block
having a cup shaped recess on one of its ends. Such cup shaped recess faces the
correspondingly shaped end of a similar block 2 which is screwed or otherwise
attached to the transmitter diaphragm 3. The rear end of the first block is
supported by a plate or disc 4 to which it is attached by a screw. The disc has
two short arms as shewn in Fig. 3 which are loosely held on screws or studs 5, 5
said studs also holding a short curved strip or spring plate 6 which may be held to
the disc 4 by the central screw as shewn. This means of attachment enables the
rear carbon block 2 to be held against. the front block 2 with a yielding pressure
as by tightening or loosening the screws 5, 5 the two ends of the spring plate 6
will be compressed or released. Between the cup shaped recesses of the two

page_text: blocks 2 is placed a mass of carbonized fibre 7. preferably a cotton or hemp fibre
which before or after carbonization may be impregnated with fine carbon or
plumbago. Other forms of microphones containing the carbonized fibre may be
employed but that shewn is one which has been found to work well.
The diaphragm 3 is held in place by the flange of a metal ring & which forms a
collecting mouth piece for the transmitter and at the same time a ineans for holding
the receiver when not in use.
The receiver is provided with a mouth piece 9 which is held by a small flange
formed on same in a metal ring 10 (Fig. 8) said ring having a turned over edge
which engages with the flange. The mouth piece 9 is first dropped into the ring!
the diaphragm 11 is placed thereon and the two are held in position by a metal
ring 12 which may he open as shewn or closed. The depth of this ring is such
that its outer edge is dush with or as shown projects slightly over the edge of the
ring 10 so that it will abut against the back plate 13 and consequently maintain
the diaphragm at a determined distance from the electro magnets 14, 14 thus
providing a ready means for setting the diaphragm at the correct distance from the
electro magnets without requiring a separate adjustment for each instrument and at
the same time clamping it in position without distorting or straining same.
ring 10 has a screwed end as shewn and on this is screwed a metal ring 15 having
a turned over edge which also holds in place the cap piece or rosette 16 of the bell
mush said rosette abutting against the other side of the base plate 13.
The
The electro magnets 14 are attached to this base plate, which is of vulcanite or
the like said magnets consisting of a horse shoe shaped iron plate having its ends
turned up, said ends being surrounded by the usual coils 14". One of the wires
from the coils is in connection with a bent spring plate 17 (Fig. 6) which is
normally in connection with a contact piece 18 said spring and contact piece being
attached to the base 13 by screws 24ª and 18" respectively. The spring 17 is
adapted to keep a ball 19 of insulating material pressed constantly through an
opening in the receiver ring or case 10 except when the latter is inserted in the
mouth 8 of the transmitter when the ball 19 is forced in as shewn in Figs. 1 and 5.
The result of this is that the spring 17 is removed from contact with the piece 18
as shewn in Fig. 5. The other wire from the coils 14 is taken to a screw 20 which
passes through the magnet from which it is suitably insulated to the other side of
the base plate 13 where it is connected to and serves as the holding means for a
spring plate 21 forming the usual spring key of a bell push. The free end of this
plate 21 is passed under a bent retaining piece 22 with which it is normally in
contact the screw 22" of said piece 22 passing through to the other side of the
base 13 where it is connected to and serves as the holding means for a plate 23
the edge of which projects slightly beyond the base as shewn in Fig. 7 and there
engages with notches 23" on the edges of the ring 12 and case 10 the object being
to facilitate the putting together of the parts as when the plate and notches
correspond the spring 17 will be in line with the ball 19 which it is necessary should
be first dropped into the case while a further object is to put the piece 22 in
contact with the metal case. The other part of the bell push consists of a contact
plate 24 secured to the base by a screw 24ª which passes through to the other
side of the base where it is connected to and serves as the holding means for the
spring 17 though it is insulated therefrom by a disc 17".
The operation of the instrument is as follows reference being made to the various
figures and to the diagrams Figs. 9 and 10. When the receiver is in the mouth of
the transınitter as shewn in Figs. 1 and 9 a current coming along the line wire 25
will pass to the terminal A on the base of the transmitter, from thence by wire 26
by flexible cord to the insulated screw 20, from the latter to the key 21, from key
to contact piece 22, from 22 through screw 22ª to piece 23, from latter to case,
from case to mouth of transmitter, from inouth of transmitter to terminal C by
means of a screw 27 which passes from the back of the transmitter and serves to
hold the mouthpiece thereto and is in connection with the binding post C. From
this post it passes by a wire to the bell, out from the bell by a wire to the

page_text: terminal D and from the latter by a wire 28 to earth or to a return wire. When
it is desired to send a signal, the receiver being still in the transmitter mouth
piece, the circuit is from one pole of a battery 29 to terminal B from the latter
through wire 32, flexible cord to screw 24", from latter to piece 24, and when key
is depressed through key 21, wire 26, flexible cord to terminal A and out to line
wire. The other pole of the battery is attached by a wire 33 to terminal D and
from thence is connected by wire 28 to earth or return.
When the receiver is removed from the transmitter mouthpiece for purposes of
conversation the circuit is from wire 25 to terminal A from the latter through
wire 26 to screw 20, from the latter through wire 34, to coils of magnet, out through
wire 35, screw 24" and to spring plate 17 which is now in contact with the piece 18
as the ball 19 is not pressed in by the transmitter mouthpiece, from piece 18 by
wire 36, through flexible cord to terminal E, from wire 31 through microphone,
out by wire 30 to terminal B, through battery to terminal D and by wire 28 to
earth or return.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. In a telephone transmitter, a microphone contact formed of or containing a
carbonized fibre, such as carbonized cotton fibre, substantially as described.
2. In a telephone transmitter, a microphone contact formed of or containing a
carbonized fibre, such as carbonized cotton fibre, such as admixture of plumbago or
other finely divided carbon, substantially as described.
3. A receiver having a spring switch and a ball or stud projecting through the
casing, adapted to be operated by an annular holding device, the arrangement
enabling the current to pass through the receiver and transmitter when the receiver
is removed, or through the signal bell when the receiver is in place, substantially as
.described.
4. A receiver case provided with a ring such as 12 adapted to maintain the coils
and magnet at a determined distance from the diaphragm and a clamping device
such as the ring 15 for securing the parts together, substantially as described.
5. The improvements in and connected with telephones substantially as described
.and illustrated.
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