IMPROVEMENTS IN TELEPHONES AND TELEPHONIC CALL MECHANISMS
Year: 1879

page_text: 15
LETTERS PATENT to Herbert John Haddan, of the Firm of Herbert and
Company, Solicitors of Patents, of 67, Strand, in the City of Westminster,
Civil Engineer, for the Invention of IMPROVEMENTS IN TELEPHONES AND
TELEPHONIC CALL MECHANISMS." A communication from abroad by Abner
Mulholland Rosebrugh, of Toronto, in the Dominion of Canada, Doctor of
Medicine.
PROVISIONAL SPECIFICATION left by the said Herbert John Haddan at
the Office of the Commissioners of Patents on the 16th April 1879.
HERBERT JOHN HADDAN, of the Firm of Herbert and Company, Solicitors of
Patents, of 67, Strand, in the City of Westminster, Civil Engineer. "IMPROVEMENTS
IN TELEPHONES AND TELEPHONIC CALL MECHANISMS." A communication from
abroad by Abner Mulholland Rosebrugh, of Toronto, in the Dominion of Canada,
Doctor of Medicine.
The Invention has for its object the combination of an improved telephone and a
signalling apparatus in one instrument, and consists of one or more permanent
magnets, which are used in common for the purpose of magnetizing the cores of the
telephone electro-magnets, and also to magnetize the cores of movable coils or
electro-magnets used for the production of induced currents for signalling purposes.
The telephone is constructed as follows:-To a diaphragm which is connected with
a mouthpiece in the usual way, and which is made of any suitable material, one or
more cylindrical pieces of magnetized steel are attached, say, one quarter of an
inch in diameter, and one inch in length. The free end expands suddenly near the
end to, say, one half inch diameter. This magnetized cylinder passes loosely
through the centre of the core of an electro-magnet, which is secured to a plate
placed about one quarter of an inch from and parallel to the telephone diaphragm.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Herbert John Haddan in the Great Seal Patent Office on the 8th
October 1879.
HERBERT JOHN HADDAN, of the Firm of Herbert and Company, Solicitors of
Patents, of 67, Strand, in the City of Westminster, Civil Engineer. "IMPROVE-
MENTS IN TELEPHONES AND TELEPHONIC CALL MECHANISMS.” A communication
from abroad by Abner Mulholland Rosebrugh, of Toronto, in the Dominion of
Canada, Doctor of Medicine.
This Invention relates more particularly to the combination of a telephone and
signalling apparatus in one instrument, and it consists,-
First. In directly or indirectly making use of a single or compound magnet in
common, both for the telephone and. for the signalling apparatus.
Second. In a method of generating different qualities of electric currents so as to
be able to effect either an armature or a diaphragm of a distant instrument or
instruments.
Third. In a method of constructing a magneto-electric signalling apparatus so
that it may be inserted in a branch line, or a derived line of any galvanic circuit,
without interfering with the action of said galvanic circuit.
Fourth. In a method of constructing a telephone so as to be able to dispense
with a diaphragm of iron or other similar material, capable in itself of producing
when vibrating induced currents in an electro-magnet in proximity thereto.
Fifth. In a new form of electro-magnet connected with a striker for ringing bells
by means of currents of opposite polarity.
In the accompanying Drawings,
Figure 1 is a plan view of an instrument embodying these improvements;
Figure 2 is an end view in section of telephone and electric generator combined;
Figure 3 is a detail of vibrating electro-magnet and bells; Figure 3* is a plan of
same; Figure 4 is a plan view of a modification of instrument without the vibrating
electro-magnet and bells; Figures 5 and 6 are views of modified forms of the tele-
phone diaphragm and electro-magnet; Figures 7, 8, and 9 are diagrams of wire
connections; Figure 10 is a view of a modified form of permanent magnet and
telephone.
Similar letters of reference indicate corresponding parts throughout.
A is a permanent magnet, either single or compound, and used in common for the
telephone and for the electric generator; B is a telephone electro-magnet; C, the
diaphragm; D, D, the induction coils or electric generator; E is a vibrating electro-
magnet with striker E³ and bells E, E; F is a push button for opening the short
circuit of the electric indicator; G is an automatic switch; H, binding post for
line; and I, binding post for ground wire; J, binding post for grounding through
high resistance medium K or indirectly through condenser L.
In Figure 1 the electro-magnet is retained in position by means of the supporting
bar M, which is secured in a suitable manner to the framework of the instrument
at N and N¹. The core ☐ of the electro-magnet B is a bollow cylinder, preferably.
of soft iron; P is a cylinder or rod, preferably of soft iron attached to the diaphragm
at Q, and after passing through the core O extends at least one eighth inch beyond
the opposite end of the core O, and terminates preferably in an adjustable button R
of soft iron, which is adjusted very near the permanent magnet A. The diaphragm C
may be composed of mica or any suitable material capable of being thrown into
vibrations by the human voice. The hollow core 0 of the electro-magnet B may
be at any convenient distance from the diaphragın, preferably however the
diaphragm is made of soft iron, and the near end of the core O is adjusted very
near to the diaphragm. In the latter case in addition to the induction between

page_text: the diaphragm and the core O, as in the "Bell " telephone, the longitudinal
vibrations of the rod P and the button R adjusted in the vicinity of the magnet
causes an increase in the magnetization and demagnetization of both the rod P and
the core O, and consequently causes an increase in the strength of the induced
current. The construction of this part of the apparatus may be modified in many
ways, as, for instance, the rod P may pass through the cores of two or more small
electro-magnets, as B, B¹, Figure 10, with soft iron buttons R, R', to vibrate
opposite the poles ou the same side as the diaphragm, or one of the electro-
magnets B' may be secured by one pole to the permanent magnet A, and the other
pole adjusted near the soft iron button R'.
Again, the permanent magnet A may be compound, or may terminate in two or
more plates, say, one quarter of an inch apart, as shewn in Figure 10, A1, A2, A³,
representing three such plates, A¹ giving attachment to the hollow core O' of the
electro-magnet B', and which gives passage to the rod P. The buttons R³, R³, are
adjusted near the plates A³, A³, respectively, and on the side towards the
diaphragm R², being adjusted near A, and Rs near plate A³. Again, the rod P,
the button R, or the core O, or all may be constructed of steel, and may or may
not be magnetized. The convex cylindrical surface of the rod P and the concave
surface of the cores 0, 0¹, are polished with graphite, as also the buttons R, R¹,
R³, R³. Still another modification of this part of the apparatus is represented in
Figures 1 and 2. A is a permanent magnet, either single or compound; B, tele-
phone electro-magnet; C, diaphragm. This diaphragm may be composed of any
convenient material capable of being thrown into vibrations by the voice. In the
latter case the rods P, P, composed of any suitable material are attached to the
diaphragm, and to their free end are attached the buttons R, R, composed of soft
iron, or any similar material susceptible to magnetic influence. These buttons R, R,
are adjusted very near to the free poles of the electro-magnet B. When two rods
and two buttons are used these buttons R, R, may be connected to each other by a
strip of soft iron or other similar material, and the connection with the diaphragm
be made by means of this strip. On the opposite side of the permanent magnet is
the moveable electro-magnet, moveable induction coils, or electric-inductor D, D.
This electric inductor may be attached to a pivoted rod and handle capable of com-
municating a 'to and fro' movement to the inductor so as to alternately bring one
of the poles of said electro-magnet or inductor alternately opposite the north and
south poles of the permanent magnet A. However, this inductor may be con-
structed so that both poles may be rotated opposite the two poles of the permanent
magnet. These coils may be made to rotate by any suitable mechanism, as for
instance, by means of traction made alternately on opposite ends of a cord, passing
over a pulley attached to the spindle of the electro magnet, or by means of a cord
or band, and a spring, or by means of a wheel and band, or by means of two or
more cog wheels, or any suitable mechanism which it is unnecessary more particularly
to describe.
A sleeve S, pulley T, and yoke U, in connection with the cores of the electric
inductor D, D, are slipped upon and insulated from the spindle V, and they are
also insulated from the framework at W, where the opposite trunnion passes from
the pulley to make electric connection with the metal spring X. The sleeve or
axis below the pulley is flattened upon opposite sides at Y, or.two segments are
insulated in such a manner that the end of the spring X when desired may simply
make contact at two opposite points during every revolution of the induction coils
D, D, and so arranged that the spring shall not touch when the cores of the electric
inductor D, D, are opposite to the poles of the permanent magnet A. The spring X
is attached to the metal frame work, and consequently short circuits the induced
currents twice during each revolution of the electro magnet by making contact
with the sleeve as the poles of the inductor recede from the poles of the permanent
magnet. This could be called a pulsatory current, and it is best adapted to produce
vibrations of great amplitude in the diaphragm of a distant telephone, and can
be used in this manner for signalling purposes, But in cases where it is desired..

page_text: to signal by means of bells an undulatory current is preferable. In this case the
spring X is not used.
In connection with this apparatus an electro-magnet can be used, of any suitable
construction, for giving a signal by an armature moving a striker when electric
currents are generated in the line. It is preferred, however, to use a pivoted
electro-magnet carrying a striker, as shewn in detail in Figures 1, 3, and 3a. E is
an electro-magnet; E1, E2, opposite poles of soft iron core; Es, striker attached to
one pole and arranged to strike the bells E; and E³, E6, E7, E³, are magnetized steel
bars placed opposite the poles E¹, E, and with these poles so arranged that two
magnets at opposite ends and opposite sides of the electro-magnet will alternately
attract and repel the soft iron core according as currents of opposite polarity traverse
the coil of the electro-magnet. Undulatory currents or currents of opposite polarity
(alternating) will cause the electro-magnet to vibrate and will cause the striker Es
to ring the bells. The electro-magnet is pivoted on insulated trunions, and in
making the connection each end of the coil is attached to a trunnion, one of which,
E, is insulated and is connected either directly or through the standard E10 with the
line wire Hat H. The standard supporting the opposite trunnion, which also
supports the permanent magnet E¹¹, is connected with the wire E¹ which extends
to the metal spring W¹. The magnets E³, E6, E7, E³, are preferably kept in a
magnetized state by induction from the "U" magnet E. The magnet E¹¹ may be
used also for supporting one of the trunnions E¹s of the electro-magnet E and also
to give support to the steel bars E5, E6, E7, E³.
Figure represents a diagram of the wire connections when the apparatus is
used in connection with the electro-magnet E and the resistance medium K, while
Figure 9 represents the wire connections when the electro-magnet E is omitted,
and when a condenser is used instead of a resistance medium. In Figure 8 H is a
binding post for the line wire H', while I is the binding post for grounding direct,
and J binding post for grounding through; K, a high resistance medium; G is a
switch for grounding either the telephone B through the contact point G³ or the
electro magnet E through the contact point G¹, a spring keeping the switch G auto-
matically in contact with G¹.
F is a push button opening the short circuit F¹, D, F, when transmitting a
signal. At all other times the electric inductor D, D, is cut out of circuit. When
the apparatus is grounded through J the line wire H' may be attached to and form a
branch line of any galvanic circuit, providing that sufficient resistance be introduced
at K.
The operation of the apparatus is as follows:-When the line is charged with
alternating currents of opposite polarity from a distant instrument the currents
take the direction of H, E, E, W₁, W², G¹, K, and thence to the ground through J,
and the pivoted electro-magnet vibrates and the striker E³ rings the bells E, E. In
giving the return signal the electric generator D, D, is made to revolve, and by
pressing the push button repeatedly a definite signal is given. The switch G is
then depressed so as to make connection at G2, and the ear is applied to the
telephone. As a modification of this both a condenser and a resistance medium
may be encased in or used in connection with the same apparatus, and so arranged
that by the use of a switch either may be used at pleasure. The resistance medium
is found the best when it is desired to use a bell signal, but in speaking or in using
pulsatory currents for signalling purposes a condenser is preferred.
In the modification represented in Figure 4 the bell signal E and the switch G
are omitted and a condenser L used instead of high resistance. With this apparatus
pulsatory currents are generated, and when at the same time the push button F is
pushed in these pulsatory currents traverse the line and cause vibrations in the
diaphragm of a distant telephone of sufficient amplitude to be used as a signal.
In this modification of the apparatus the telephone is constantly in circuit. By
putting the condenser in circuit the apparatus may be placed in either a branch line
or a derived line of any galvanic circuit. The condenser may be placed either
inside or outside of the instrument, and may be inserted either between the instru-

page_text: ment and the line or between the instrument and the ground. The same is true
also of the resistance medium.
The telephone electro-magnet B may, if convenient, be attached to a bar of iron
or steel, which bar is either directly or indirectly magnetized by the permanent
magnet A, or the electro-magnet B may be suspended near to without being in
actual contact with the magnet A. The diaphragm Cis preferably secured between
elastic supports at its outer edge, and attached to a rigid casing or framework.
The accoustic space between the diaphragm and framework should be as shallow as
possible compatible with free vibrations. The speaking tube communicating with
the accoustic space may be either rigid or pliable and of any convenient length.
The framework of the instrument should be rigid and may be composed of any
suitable material. The handle for controlling the gearing is preferably on the same
side of the instrument as that of the telephone.
I do not claim broadly the ringing of bells by means of alternating currents.
I do not claim a soft iron diaphragm or its magnetic equivalent in connection with
a telephone electro-magnet. I do not claim broadly an automatic switch or push
button, and I do not claim broadly a fixed telephone electro-magnet with a
moveable soft iron core attached to a diaphragm.
What I claim as my Invention is,-
1. The combination of a speaking telephone and moveable induction coils with
a single or compound permanent magnet in common to both, as and for the purpose
specified.
2. The combination of a speaking telephone and moveable induction coils with
a permanent magnet common to both and a receiving signal apparatus, as and for
the purpose specified.
3. The combination of a high resistance medium and moveable induction coils,
as and for the purpose set forth.
4. The combination of a high resistance medium, moveable induction coils, and
a speaking telephone.
5. The combination of a high resistance medium, moveable induction coils, and a
receiving signal apparatus.
6. The combination of a high resistance medium, moveable induction coils, a
speaking telephone, and a receiving signal apparatus.
17. The combination of a condenser & moveable induction coils.
8. The combination of a condenser, moveable induction coils, and a speaking
telephone.
9. The combination of a condenser, moveable induction coils, and a receiving
signal apparatus.
10. The combination of a condenser, moveable induction coils, a speaking tele-
phone, and a receiving signal apparatus.
11. The combination of a high resistance medium, moveable induction coils, and
a circuit breaker.
12. The combination of a high resistance medium, moveable induction coils, a
speaking telephone, and a circuit breaker.
13. The combination of a high resistance medium, moveable induction coils, a
receiving signal apparatus, and a circuit breaker.
14. The combination of a high resistance medium, moveable induction coils, a
speaking telephone, a receiving signal apparatus, and a circuit breaker.
15, The combination of a condenser, moveable induction coils, and a circuit
breaker.
16. The combination of a condenser, moveable induction coils, a speaking tele-
phone, and a circuit breaker.
17. The combination of a condenser, moveable induction coils, a receiving signal
apparatus, and a circuit breaker.
18. The combination of a condenser, moveable induction coils, a speaking tele-
phone, a receiving signal apparatus, and a circuit breaker.

page_text: 19. The combination of a high resistance medium, moveable induction coils, a
circuit breaker, and an automatic switch.
20. The combination of a high resistance medium, moveable induction coils, a
speaking telephone, circuit breaker, and automatic switch.
21. The combination of a high resistance medium, moveable induction coils, a
receiving signal apparatus, a circuit breaker, and automatic switch.
22. The combination of a high resistance medium, moveable induction coils, a
speaking telephone, a receiving signal apparatus, a circuit breaker, and an automatic
switch.
23. The combination of a condenser, moveable induction coils, a circuit breaker,
and an automatic switch.
24. The combination of a condenser, moveable induction coils, a speaking tele-
phone, a circuit breaker, and an automatic switch.
25. The combination of a condenser, moveable induction coils, a receiving signal
apparatus, a circuit breaker, and an automatic switch.
26. The combination of a condenser, moveable induction coils, a speaking
telephone, a receiving signal apparatus, a circuit breaker, and an automatic switch.
27. The combination of the permanent magnet A, insulated moveable induction
coils D, D, with the short circuiting spring X, a condenser L, and a speaking
telephone, so as to be able to insert the apparatus in a branch line or a derived line
of a galvanic circuit, substantially as described.
28. An electro-magnet E pivoted on insulated trunnions, with one or both poles.
adjusted between fixed armatures of magnetized steel, and arranged to vibrate
when electric currents of opposite polarity traverse the line in which it is inserted,
substantially as described."
29. The pivoted electro-magnet E, with striker Es, in combination with the
permanent magnet El, bells E, E, and the wire connections through which the
instrument is put in circuit, substantially as specified.
30. In a speaking telephone the combination with a diaphragm, composed of any
suitable material, of one or more rods of iron or steel attached to diaphragm near
its centre, and one or more buttons of iron or steel attached to said rod or rods,
one or more electro-magnets B, B¹, with perforated cores, and a permanent
magnet A divided into one or more plates of similar polarity, said plates being so
arranged that the longitudinal vibrations of the rod P shall cause the button Ⓡ to
vibrate either in proximity to the pole of the electro-maguet B (on the side towards
the diaphragm) or in proximity to the permanent magnet A.
31. A permanent magnet A with one or both poles divided into two or more
plates of similar polarity.
32. The telephone electro-magnet B, with hollow core O, in combination with
the diaphragm rod P, and two or more iron or steel buttons attached thereto.
33. One or more supplemental telephone electro-magnets B' in combination with
the electro-magnet B, hollow core O, diaphragm rod P, and iron or steel buttons
R, R¹, and a permanent magnet.
34. One or more supplemental electro-magnets B³, with hollow core 0¹, in
combination with the permanent magnet with divided plates A¹, As, A³, the electro-
magnet with hollow core B, diaphragm C, rod P, and iron or steel buttons R, R¹,
R² R³.
In witness whereof, I, the said Herbert John Haddan. have hereunto set