Improvements in Telephone Station Apparatus.
Year: 1899

page_text: Date of Application, 10th Jan., 1899-Accepted, 15th Apr., 1899
Improvements in Telephone Station Apparatus.
I, DAVID HENRY WILSON, Engineer, of No. 1410, Marquette Building, Chicago,
County of Cook, State of Illinois, United States of America, do hereby declare
the nature of my invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement:
-
My invention relates to telephone and transformer systems and parts thereof
and has for its object to provide a new and improved system and construction.
Referring to the accompanying drawings, wherein my invention is illustrated
diagrammatically,
Figure 1 is a perspective view of one form of telephone box showing the
mechanism in position;
Figure 2 is a diagrammatic view showing the transformer and the different
circuits.
In Figure 1, I have shown a construction where the parts are conveniently
assembled in operative relation to each other. The transformer or induction
coil used in this system is of a new and improved form and consists of a primary
coil A provided with the core A¹ formed into opposed pole pieces, between which
the secondary coil A2 is supported, the core A³ of said secondary coil forming
a part of the magnetic circuit of the primary coil. This secondary coil and core
may be stationary if desired, but I have illustrated it as being movably supported
in position. In the drawing, I have shown a part of the primary coil A as
extending around the core A3 of the secondary coil, but this construction of course
may be varied. When the secondary coil is movably supported, I may connect
with it, as by means of the shaft A7, a receptacle A containing mercury or the
like and provided with the contact points A5 A6. A rod A8 is attached at one end
to the arm A on the shaft A, the other end being fastened to the spring A⁰ which
normally holds the core of the secondary coil in an angular position, as shown
in Figure 2. If the primary coil is energized when the core of the secondary
coil is in this angular position, the magnetic forces acting upon said core will
be unbalanced and the core and the receptacle A will be moved from their
angular position. The receptacle A is in the circuit of the primary coil and
the contact point A5 is so arranged that it will be withdrawn from the receptacle
A and break the circuit of the primary coil, when said coil is energized so as
to move the secondary coil and the receptacle A. The spring then pulls the
secondary coil and receptacle back to their normal position, so as to again com-
plete the circuit, and the operation above described is repeated. The induced
current in the secondary coil caused by making and breaking the circuit in the
primary coil passes out on the main line in the usual manner. A call bell B
is located in the circuit of the secondary coil. The several circuit connections
are made at the rear of the base-board "B¹ and are shown diagrammatically in
Figure 2. The lever C, which supports the receiver C¹, is pivoted at C2 and

page_text: is provided with the associated contact springs C³, C+ and C³ and the insulated
contact blocks C and C. The expansion spring C¹s moves the lever C upward
when the receiver C is removed from its hook. The contact spring C is con-
nected to one pole of the primary coil by the wire C8 and to the contact point A5
of the receptacle A by the conductor Co. The contact spring C is connected
to the line wire C10 which leads to the next station. This line wire C10 is also
connected to the lever C. The. contact spring. C³ is connected with. a switch D
provided with the insulated contact plate D', which is connected by conductor 1)
with a source of electric supply E.
A conductor E' leads from the source of elec-
tric supply to the primary coil A. Associated with the switch D are the contact
springs D, D and 15. The contact spring D³ is connected by conductor E2 with
contact point A of the receptacle A. The contact spring D is connected by
conductor E3 with the bell B and the contact spring D is connected by conductor
E with conductor C" which connects the receiver C. with the secondary coil.
The switch D is normally held against the contact spring D by the spring 16.
The contact block C on the lever, Cisconnected to the transmitter F', said
transmitter being connected by conductor F4 with the conductor D³ which leads
to the source of electric supply...
When it is desired to ring up the central station, or any other station with
which connection has been made, the switch D is moved away from the spring 1*
and in contact with the contact springs 13 and D³. The primary circuit will
then be as follows: From the source of electric supply E by wire E to the
primary coil A, thence by conductors C8 and. to the receptacle A, thence by
contact A, conductor 2, contact D³ and conductor 2 back to the source of
electric supply.. The secondary coil A2 and receptacle Awill now be moved or
oscillated and a pulsating current will be generated in the secondary coil which
will be traced as follows: From secondary coil. A2 along conductors C¹¹ and E
to contact spring D³, thence through switch D, contact spring: C³, lever .C and
main line Co to bell or alarm of connected station, and thence. by ground to bell
or alarm B and back to secondary coil A2. When the switch D is released, it
returns to its former position in contact with the spring D. If now the
receiver C¹ is taken from the lever C, the circuit through the transmitter and
receiver will be completed by the movement of the lever C due to the spring (18
and the circuit through the transmitter will be as follows: From the source of
electric supply E to the primary coil A, thence by conductor Cs and contacts C+
and C to the transmitter F¹, thence by conductors F and D2 to the source of
electric supply, the circuit breaking device for ringing being now out of the
circuit. By talking into the transmitter F the resistance in the circuit of the
primary coil will be varied so as to produce a variation in the current there-
through, and hence an undulating current is set up in the secondary coil which
passes through and operates the receiver of the connected station. When the
receiver is placed back on the lever C, the bell is in condition to be rung by the
connected station.
It is of course evident that any desired signalling device may be used, for,
when a transformer is used with a varying current, as in a telephone system,
or with an alternating current, it is of course evident that it is not necessary
to use the circuit breaker and the secondary coil may be either allowed to move
or may be held stationary as desired. I have found that with a transformer such
as herein described, that is, having one coiled conductor having a core of magnetic
material, with pole pieces in proximity to each other, and a second coiled conductor
provided with a core mounted between the pole pieces of the core of said first
coiled conductor, so as to form part of the magnetic circuit, I am enabled to
produce results which cannot be produced by the ordinary transformer, or any
of the transformers now upon the market. In this construction the cooperation
of the coils is such as to produce new results.
I of course do not limit myself to the construction shown and have only set
forth this particular construction to make my invention clear.

page_text: Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, I declare that what
I claim is:-
1. The telephone system herein shown and described.
2. A telephone system, comprising an induction coil including a primary and
a secondary coil, one coil provided with a core having opposed pole pieces, the
other coil interposed between said opposed pole pieces, so as to be in the path
of the magnetic circuit between such pole pieces, and a transmitter and receiver
connected respectively with the primary and secondary coil of the induction coil
so as to co-operate therewith.
3. A telephone system, comprising an induction coil including a primary and
a secondary coil, one coil provided with a core having opposed pole pieces, the
other coil interposed between said opposed pole pieces, so as to be in the path
of the magnetic circuit between such pole pieces, a transmitter and receiver
connected respectively with the primary and secondary coil of the induction coil
so as to co-operate therewith and the system of circuits herein shown and described
for connecting the parts together.
4. The combination in a telephone system of an induction coil provided with
a movable core, a circuit breaker associated therewith and operated by the move-
ment of said core, a receiver, a transmitter, a signalling device, and a system
of circuits so arranged that the circuit breaker is in circuit with the primary
coil when the signalling device is operated and is cut out of circuit when the
transmitter is being used, as herein shown and described.
5. The induction coil herein shown and described.
6. An induction coil, comprising a coiled conductor having a metallic core
with opposed pole pieces, a second coiled conductor provided with a metallic
core, said second conductor and core mounted between the poles of the core of said
first conductor, so as to form part of its magnetic circuit.
F. WISE HOWORTH,
46, Lincoln's Inn Fields, London, W.C.,
Agent for the Applicant.